Refractive Surgery Subspecialty Day Syllabus (PDF 6MB)

Transcription

Refractive Surgery
2012
The Era of Lasers
and Lenses
Program Directors
David R Hardten MD and
Michael C Knorz MD
The Annual Meeting of ISRS
Sponsored by the International Society of Refractive Surgery (ISRS)
McCormick Place
Chicago, Illinois
Friday – Saturday, November 9 – 10, 2012
Presented by:
The American Academy of Ophthalmology
Refractive Surgery 2012 Planning Group
David R Hardten MD
Program Director
Michael C Knorz MD
Program Director
Amar Agarwal MD
Daniel S Durrie MD
Sonia H Yoo MD
Former Program Directors
2011
Amar Agarwal MD
David R Hardten MD
2010
Ronald R Krueger MD
Amar Agarwal MD
2009
Gustavo E Tamayo MD
Ronald R Krueger MD
2008
Steven C Schallhorn MD
Gustavo E Tamayo MD
2007
Francesco Carones MD
2006
Steven E Wilson MD
2005
Jorge L Alio MD PhD
Steven E Wilson MD
2004
John A Vukich MD
Jorge L Alio MD PhD
2003
Terrence P O’Brien MD
John A Vukich MD
2002
Daniel S Durrie MD
Terrence P O’Brien MD
2001
Douglas D Koch MD
Daniel S Durrie MD
2000
Richard L Lindstrom MD
Douglas D Koch MD
1999
Marguerite B McDonald MD
1998
Peter J McDonnell MD
1995 – 1997 Peter J McDonnell MD
2012 ISRS Executive Committee
Amar Agarwal MD
President
Committee Members
John So-Min Chang MD
Joseph Colin MD
Alaa ElDanasoury MD
David R Hardten MD
A John Kanellopoulos MD
Vikentia Katsanevaki MD
Ronald R Krueger MD
J Bradley Randleman MD
Gustavo E Tamayo MD
William B Trattler MD
Subspecialty Day Advisory Committee
William F Mieler MD
Associate Secretary
Donald L Budenz MD MPH
Daniel S Durrie MD
Robert S Feder MD
Leah Levi MBBS
R Michael Siatkowski MD
Jonathan B Rubenstein MD
Secretary for Annual Meeting
Staff
Melanie R Rafaty CMP, Director, Scientific
Meetings
Ann L’Estrange, Scientific Meetings Specialist
Brandi Garrigus, Presenter Coordinator
Debra Rosencrance CMP CAE, Vice
President, Meetings & Exhibits
Patricia Heinicke Jr, Editor
Mark Ong, Designer
Gina Comaduran, Cover Design
©2012 American Academy of Ophthalmology. All rights reserved. No portion may be reproduced without express written consent of the American Academy of Ophthalmology.
ii
2012 Subspecialty Day | Refractive Surgery
Dear Colleague:
On behalf of the International Society of Refractive Surgery (ISRS), it is our pleasure to welcome
you to Chicago and Refractive Surgery 2012: The Era of Lasers and Lenses. This meeting assembles
a great lineup of international leaders in refractive surgery and provides a forum for exchange of the
latest information in our field.
In this year’s Subspecialty Day Meeting we will focus mainly on cornea-based refractive surgery
on Friday, and then on Saturday we will stress the lens-based refractive surgical topics. We open
the session on Friday with the “hot and happening” topic of intracorneal inlays. A video conveys
much more than a picture, and so we proudly present the video journey of complicated cataract and
refractive surgery, showcasing the variety of challenges a refractive surgeon has to face, as well as
various management strategies. Collagen crosslinking is another treatment that today’s refractive
surgeon has to master, and so it has also been given special emphasis. Friday ends with the Cornea
Video Corner, which covers the latest topics in corneal surgery.
Saturday we open with another hot and happening topic, femtosecond cataract surgery. The exciting
session “Lull Before the Storm” shows in a video format how one can anticipate and survive a variety
of disasters. The problems and advantages of the different phakic IOLs and the management of astigmatism for the lens-based refractive surgeon are also covered on Saturday. We end Saturday with the
annually anticipated “Hot, Hotter, and Hottest” topics from the Journal of Refractive Surgery.
New this year, there will be a session comprised solely of free papers, which will run concurrently
with the Refractive Surgery Subspecialty Day meeting on Friday, Nov. 9, on the topic “Innovations
in Refractive Surgery.”
The Break With the Experts session, which has received high reviews each year, returns again this
year, allowing you to interact directly with top faculty from around the world. On Friday morning,
we will also acknowledge and honor the ISRS award winners. We hope to see that at the end of the
two days you will have learned enough to handle the most challenging refractive surgical cases.
Our faculty have spent innumerable hours preparing their presentations and course materials to
provide the most up-to-date and comprehensive review of their topics. We thank them for all of
their efforts and for sharing their expertise during the program.
It would have been impossible to develop this program without your cooperation. This is why we
request that you assist us by completing the evaluation. We carefully review all comments to better
understand your needs, so please indicate the strengths and shortcomings of today’s program and
assist us in brainstorming about new ways to fulfill your objectives.
Again, we welcome you to Refractive Surgery 2012: The Era of Lasers and Lenses; we hope you
find it educational, exciting and enjoyable.
Sincerely,
David R Hardten MD
Program Director
Michael C Knorz MD
Program Director
Refractive Surgery 2012 Contents
Program Directors’ Welcome Letter ii
CME iv
2012 Award Winners v
Faculty Listing x
Program Schedule xxv
Section I:
Cornea Point-Counterpoint 1
Section II:
Cornea Video Complications 14
Keynote Lecture: Corneal Presbyopic Surgery 20
Section III:
Corneal Crosslinking 21
Free Paper Session I (Grand Ballroom S100ab) 54
Keynote Lecture: Presbyopic Lenses—Where Are We Headed? 58
Section IV:
Presbyopia 60
Free Paper Session II (Grand Ballroom S100ab) 77
Section V:
European Society of Cataract and Refractive Surgery (ESCRS) Symposium:
Corneal Refractive Surgery—Advanced Techniques 81
Free Paper Session III (Grand Ballroom S100ab) 94
Section VI:
Lens Point-Counterpoint 98
Section VII:
Lens Complications: Video Presentations 110
Keynote Lecture: Overview of Phakic IOLs 119
Section VIII:
The Journal of Refractive Surgery’s Hot, Hotter, Hottest—Late Breaking News 121
Troutman Prize 121
Keynote Lecture: The Future of Laser Refractive Lens Surgery 129
Section IX:
Laser Refractive Lens Surgery Symposium 131
Section X:
Foundations of Refractive Surgery 147
E-Posters 161
Faculty Financial Disclosure 191
Presenter Index 198
Electronic version of Syllabi available at
www.aao.org / 2012syllabi
iii
iv
CME Credit
Academy’s CME Mission Statement
The purpose of the American Academy of Ophthalmology’s
Continuing Medical Education (CME) program is to present ophthalmologists with the highest quality lifelong learning
opportunities that promote improvement and change in physician practices, performance or competence, thus enabling such
physicians to maintain or improve the competence and professional performance needed to provide the best possible eye care
for their patients.
2012 Refractive Surgery Subspecialty Day Meeting
Learning Objectives
Upon completion of this activity, participants should be able to:
• Evaluate the latest techniques and technologies in refractive surgery
• Compare the pros and cons of various lens- and cornealbased modalities, including presbyopic and toric IOLs
• Identify the current status and future of laser refractive
lens surgery using femtosecond lasers
• Describe “total refractive surgery”: a surgery that involves
many different procedures, from intraocular procedures,
such as cataract surgery and phakic lenses, to extraocular
procedures, such as intrastromal rings, corneal inlays, collagen crosslinking, and excimer/femtosecond laser surgery
• Identify evolving surgical approaches for presbyopia
2012 Refractive Surgery Subspecialty Day Meeting
Target Audience
The intended audience for this program is comprehensive ophthalmologists; refractive, cataract, and corneal surgeons; and
allied health personnel who are performing or assisting in refractive surgery.
2012 Refractive Surgery Subspecialty Day CME
Credit
The American Academy of Ophthalmology is accredited by the
Accreditation Council for Continuing Medical Education to provide continuing medical education for physicians.
The American Academy of Ophthalmology designates this
live activity for a maximum of 14 AMA PRA Category 1 Credits™. Physicians should claim only the credit commensurate with
the extent of their participation in the activity.
Scientific Integrity and Disclosure of Financial
Interest
The American Academy of Ophthalmology is committed to
ensuring that all continuing medical education (CME) information is based on the application of research findings and the
implementation of evidence-based medicine. It seeks to promote
balance, objectivity and absence of commercial bias in its content. All persons in a position to control the content of this activity must disclose any and all financial interests. The Academy has
mechanisms in place to resolve all conflicts of interest prior to an
educational activity being delivered to the learners.
Attendance Verification for CME Reporting
Before processing your requests for CME credit, the Academy
must verify your attendance at Subspecialty Day and/or the Joint
Meeting. In order to be verified for CME or auditing purposes,
you must either:
• Register in advance, receive materials in the mail and turn
in the Final Program and/or Subspecialty Day Syllabus
exchange voucher(s) onsite;
• Register in advance and pick up your badge onsite if materials did not arrive before you traveled to the meeting;
• Register onsite; or
• Use your ExpoCard at the meeting.
CME Credit Reporting
Grand Concourse Level 2.5; Academy Resource Center,
Hall A - Booth 508
Attendees whose attendance has been verified (see above) at the
2012 Joint Meeting can claim their CME credit online during the
meeting. Registrants will receive an e-mail during the meeting
with the link and instructions on how to claim credit.
Onsite, you may report credits earned during Subspecialty Day
and/or the Joint Meeting at the CME Credit Reporting booth.
Academy Members: The CME credit reporting receipt is not a
CME transcript. CME transcripts that include 2012 Joint Meeting credits entered onsite will be available to Academy members
on the Academy’s website beginning Dec. 3, 2012.
NOTE: CME credits must be reported by Jan. 16, 2013.
After the 2012 Joint Meeting, credits can be claimed at
www.aao.org/cme.
The Academy transcript cannot list individual course attendance. It will list only the overall credits spent in educational
activities at Subspecialty Day and/or the Joint Meeting.
Nonmembers: The Academy will provide nonmembers with
verification of credits earned and reported for a single Academysponsored CME activity, but it does not provide CME credit
transcripts. To obtain a printed record of your credits, you must
report your CME credits onsite at the CME Credit Reporting
booths.
Proof of Attendance
The following types of attendance verification will be available
during the Joint Meeting and Subspecialty Day for those who
need it for reimbursement or hospital privileges, or for nonmembers who need it to report CME credit:
• CME credit reporting/proof-of-attendance letters
• Onsite Registration Form
• Instruction Course Verification
Visit the Academy’s website for detailed CME reporting information.
v
Awards
2012 José I. Barraquer Lecture and Award
Casebeer Award
The José I Barraquer Lecture and Award honors a physician who has
made significant contributions in the field of refractive surgery during
his or her career. This individual exemplifies the character and scientific
dedication of José I Barraquer, MD—one of the founding fathers of
refractive surgery.
The Casebeer Award recognizes an individual for his or her outstanding
contributions to refractive surgery through nontraditional research and
development activities.
Günther Grabner MD graduated in medicine in 1974 from the University of
Vienna Medical School and started
working at the Second University Eye
Clinic in May 1975. He is the founder of
Austria’s first Eye Bank (1977). In
1981/1982 he was a corneal and uveitis
fellow at the Francis I Proctor Foundation (University of California, San Francisco). Following his return to Austria,
Günther Grabner MD
he started the cornea and uveitis units of
the clinic and was appointed associate
professor in 1983. He started a center for refractive corneal surgery in 1985 and received an associate professorship from the
medical faculty in 1990. In January 1993 he was appointed
director and full professor at the Eye Clinic of the Paracelsus
Medical University in Salzburg, where he has been working ever
since.
Dr. Grabner is a member of several national and international
scientific societies, vice president of the Salzburger Ärztegesellschaft, member of “IIIC,” the Council of the European Society
of Ophthalmology (SOE), and the steering committee of the
KPro Study Group. A member of the Austrian Ophthalmological
Society (ÖOG) since 1975, he was elected permanent scientific
secretary for a period of six years, re-elected in 2005, and elected
president from 2009 to 2011. He served on the editorial board
of IOC (1983-1997), the Journal of Cataract and Refractive
Surgery (1990-2005), and continues with the Journal of Refractive Surgery and Der Ophthalmologe. He is editor of Klinische
Monatsblätter für Augenheilkunde and coeditor of Spektrum der
Augenheilkunde.
To date Dr. Grabner has published over 200 articles in peerreviewed journals and several book chapters, received several
awards and given numerous invited lectures and courses at
national and international meetings. His current research interests focus on corneal and intraocular presbyopia and astigmatism surgery with implants and lasers, development of a system
to precisely assess near visual acuity (the Salzburg Reading
Desk), keratoprosthesis surgery, glaucoma epidemiology (the
Salzburg Glaucoma Study) and IOL implant surgery.
Prof. Zoltan Z Nagy has been working
in ophthalmology since 1986. Currently
he is a professor at the Department of
Ophthalmology, Semmelweis University,
Budapest, Hungary and serves as a vice
dean of the Faculty of General Medicine.
His main interest in ophthalmology is
cataract and refractive surgery.
He started refractive surgery first in
Hungary in 1992, performing all kinds
Zoltan Z Nagy MD
of refractive procedures: PRK, LASIK,
epi-LASIK, LASEK, PTK, and femtoLASIK. Overall, he operated more than 30,000 eyes, with all
kinds of refractive errors. He discovered the role of harmful
ultraviolet-B effects during corneal avascular wound healing,
which was published in Ophthalmology in 1997. This is his most
cited article so far. He has published more than 200 articles in
English, and in Hungarian, he has written 20 book chapters.
In 2008 Dr. Nagy performed the world’s first femtolaserassisted cataract surgery. He published his first clinical results
with femtolaser cataract surgery in peer-reviewed ophthalmic
journals since the first procedure. In 2010 he received the Waring
Medal for the best publication in the Journal of Refractive Surgery. He is a member of the Executive Board of the International
Society of Refractive Surgery and a co-opted member of the
European Society of Cataract and Refractive Surgery Board.
vi
Awards
Founders’ Award
Dr. ElDanasoury is the immediate past president of the International Society of Refractive Surgery (ISRS). He is among the
very first refractive surgeons to perform excimer laser surgery
in the world and was the first to introduce many ophthalmic
procedures to the Middle East over the last two decades, including phakic IOLs, intracorneal ring segments, conductive keratoplasty, crosslinking, corneal inlays and recently femtosecond
cataract laser surgery.
He also has many peer-reviewed publications and book chapters, many awards and recognitions, invited lectures, and several
hundred presentations at international meetings to his credit. He
serves on the editorial board of the Journal of Refractive Surgery
(JRS) and the Middle East Africa Journal of Ophthalmology
(MEAJO). He holds membership at many international societies
including ISRS, the Academy, the European Society of Cataract and Refractive Surgery, the American Society of Cataract
and Refractive Surgery, the Saudi Ophthalmological Society,
the Egyptian Ophthalmological Society, and the Asian Cornea
Society and has been a member of the International Intraocular
Implant Club (IIIC) since 2009. Dr ElDanasoury has received
many awards including the 2009 Kritzinger Memorial Award
of the ISRS/AAO (2009), the Academy’s Achievement Award
in 2007, and the Pan-Arab African Council of Ophthalmology
(PAACO) Award in 2005. He has also been the recipient of
many regional ophthalmological societies’ awards, including the
Sudanese Society of Ophthalmology Award in 2001, the Jordanian Society of Ophthalmology Award in 1999, the Lebanese
Society of Ophthalmology Award in 1998, and the Kuwait Society of Ophthalmology Award in 1997.
The Founder’s Award recognizes the vision and spirit of the Society’s
founders by honoring an ISRS member who has made extraordinary contributions to the growth and advancement of the Society and its mission.
Dr. ElDanasoury completed his medical
studies at the school of medicine, Ain
Shams University, Cairo, in 1986 and
later obtained a masters degree in ophthalmology from the same university in
1989. He then moved to Jeddah, Saudi
Arabia, to join the Magrabi Eye Hospital, where he completed a two-year fellowship in Cornea and Refractive Surgery under George O Waring III at the
Alaa ElDanasoury MD
Magrabi Eye Hospital in Jeddah. In
FRCSed
1994, he passed the necessary examinations at the Royal College of Surgeons,
Edinburgh, and is a certified Fellow.
In 1995 Dr. ElDanasoury served as cornea and refractive surgery consultant and subsequently as medical director at Magrabi
Eye & Ear Center in the United Arab Emirates, where his performance of duty was impeccable. In 2001 he relocated to his present duties at the Magrabi Hospital in Jeddah, Saudi Arabia.
Dr. ElDanasoury currently serves as chief medical officer
and director of the Cornea and Refractive Surgery Units of the
Magrabi Hospitals and Centers in the Middle East. Magrabi
Hospital is a chain of 21 hospitals and centers, the largest in the
Middle East. Dr. ElDanasoury also chairs the Scientific Committee of the Middle East Africa Council of Ophthalmology
(MEACO) and supervises the scientific programs of MEACO
meetings. In 2011 he was elected to serve as a member of the
American Academy of Ophthalmology’s (the Academy) Board
of Trustees; he is the first non-American to serve in this position.
His additional duties include supervising the Magrabi Health
Care quality programs and medical educational activities, including advanced lamellar corneal surgery instructional courses and
hands-on training for regional cornea and refractive surgeons.
He considers his highest achievement to be training more than
12 cornea and refractive surgery fellows; some of them are now
leading ophthalmologists in their own countries.
Awards
vii
Kritzinger Memorial Award
Lans Distinguished Award
The Kritzinger Memorial Award recognizes an individual who embodies
the clinical, educational and investigative qualities of Dr. Michiel Kritzinger, who advanced the international practice of refractive surgery.
The Lans Distinguished Lecturer Award honors Dr. Leedert J Lans.
Given annually, the award is given to an individual who has made innovative contributions in the field of refractive surgery, especially in the
correction of astigmatism.
Professor Dan Reinstein is an American
born, British-, American- and Canadianeducated refractive surgeon. After graduating from the Cambridge University
School of Medicine in 1989, he spent
several years at the Weill Medical College of Cornell University in New York
as a Bioengineering Fellow, developing
very high-frequency (VHF) digital ultrasound technology (Artemis) for studying
Dan Reinstein MD
the microanatomical structure of the cornea in vivo, with the ultimate goal of
applying this to study and improve excimer corneal and phakic
intraocular refractive surgery. The Artemis has led to many discoveries and developments in refractive surgery since 1992, with
over 80 peer-reviewed publications, 30 book chapters and 500
presentations and lectures. Prof. Reinstein established the London Vision Clinic in 2002 as a private, academic refractive surgery practice. He has been the lead refractive surgery consultant
to Carl Zeiss Meditec for over 10 years, developing many of their
tools for improving excimer technology, including Laser Blended
Vision, safely extending the range of corneal refractive surgery
and all femtosecond corneal refractive surgery (ReLEx). Linked
to the diagnostic capabilities of the Artemis technology, he
devotes much of his clinical time to therapeutic corneal refractive
problem solving, including algorithms for stromal surface topography-guided therapeutic ablation.
Noel Alpins MD FACS is an active cataract and refractive surgeon and is the
medical director of NewVision Clinics in
Melbourne, Australia. Dr. Alpins has
spoken widely on cataract and refractive
surgery topics and has been a keynote
speaker at many Australian and international meetings. He pioneered small-incision cataract surgery in Victoria and is a
foundation and current member of the
Noel Alpins MD FACS
Excimer Laser & Research Group. He is
also an associate fellow at the University
of Melbourne, where he completed his Diploma of Ophthalmology in 1977 and FRACS prior to commencing practice in general
ophthalmology. He is on the Royal Australian and New Zealand
College Ophthalmologists scientific program committee. He is
on the editorial boards of the Journal of Cataract and Refractive
Surgery, Ocular Surgery News, Eurotimes and the International
Scholarly Research Network (ISRN) series of journals. He has
published widely in these and other ophthalmic information
journals and has authored more than 20 book chapters. Dr.
Alpins has developed new techniques in the treatment and analysis of astigmatism. He has developed the ASSORT computer program for astigmatism calculation for toric implants and vector
analysis and for outcomes analysis of cataract and refractive surgery. Among other recognitions, Dr. Alpins received the 2006
Gold Medal from the International Academy for Advances in
Ophthalmology and gave the Council Lecture at the 2010
Annual Scientific Congress of the Royal Australian and New
Zealand College of Ophthalmologists (RANZCO). He has been
an Australia Day Ambassador since 2011.
viii
Awards
Lifetime Achievement Award
Presidential Recognition Award
The Lifetime Achievement Award honors an ISRS member who has
made significant and internationally recognized contributions to the
advancement of refractive surgery over his or her career.
The Presidential Recognition Award is a special award that honors the
recipient’s dedication and contributions to the field of refractive surgery
and to the ISRS.
Jorge L Alió is professor and chairman of
Ophthalmology at the Miguel Hernández University, Alicante, Spain, and formerly chairman of Ophthalmology at the
University of Alicante, Spain. He has
been appointed with several visiting professorships at universities in the United
States and Europe. He has medical and
doctorate degrees with first-class honors
from the Complutense University of
Jorge L Alio MD PhD
Madrid, Spain.
Dr. Alió’s main research interests
include refractive, lens and corneal surgery, ocular inflammation
and preventative ophthalmology. He has (co-)authored over 640
original articles in peer-reviewed scientific journals and is author
or editor of 74 books and over 230 book chapters. He has made
over 1700 national and international scientific presentations in
ophthalmology congresses. His main contributions have been in
the area of excimer laser refractive surgery, microincisional lens
surgery, and multifocal accommodative and premium IOLs.
Dr Alió has received multiple awards and distinctions for
clinical and research work, including the presidency of the International Society of Refractive Surgery (ISRS) from 2006-2008,
LXIII chair of the Academia Ophthalmologica Internationalis,
and the Barraquer Award (ISRS-American Academy of Ophthalmology), among over 20 other international and national
recognitions. He is also member of 26 scientific societies and
holds executive committee positions in numerous international
ophthalmic organizations.
In 1996 Dr. Alió founded the Jorge Alió Foundation for the
Prevention of Blindness, with humanitarian campaigns on a
national and international level, currently operating in Mauritania. The Foundation created the Miradas (“glances”) art contest,
with award-winning paintings featured on the cover page of the
Journal of Refractive Surgery. The Foundation is also dedicated
to education in medical and visual sciences.
A summa cum laude graduate of Harvard College and Harvard Medical
School, David F Chang MD completed
his residency at the University of California, San Francisco (UCSF), where he is
now a clinical professor. He previously
chaired the American Society of Cataract
and Refractive Surgery (ASCRS) Cataract Clinical Committee and is the current ASCRS president. Dr. Chang is also
David F Chang MD
chairman of the American Academy of
Ophthalmology’s (the Academy) Cataract Preferred Practice Pattern Committee, immediate past chair
of the Academy’s Practicing Ophthalmologist Curriculum Panel
for Cataract/Anterior Segment, and in 2009 completed his fiveyear term as chair of the Academy’s Annual Meeting program
committee. He is a board member of the ASCRS Foundation and
serves on the medical advisory board of Himalayan Cataract
Project and Project Vision. Dr. Chang is the chief medical editor
of EyeWorld, associate international editor for the Asia-Pacific
Journal of Ophthalmology, and served for five years as co-chief
medical editor for Cataract and Refractive Surgery Today.
Dr. Chang has received the highest honors for cataract surgery: from the ASCRS (the Binkhorst Medal), from the Academy (the Kelman Lecture), from the Asia Pacific Association
of Cataract & Refractive Surgery (the Lim Medal), from the
United Kingdom and Ireland Society of Cataract & Refractive Surgery (the Rayner Medal), from the Canadian Society of
Cataract and Refractive Surgery (the Stein Lecture and Award),
from the Indian Intraocular Implant & Refractive Society (the
Gold Medal), from the Italian Ophthalmological Society (the
Strampelli Medal) and from the Royal Australia and New Zealand College of Ophthalmologists (the Gregg Medal). In 2006,
he became only the third ophthalmologist to ever receive the
Charlotte Baer Award, honoring the outstanding clinical faculty
member at the UCSF Medical School. Dr. Chang is also a fivetime recipient of the Academy’s Secretariat Award.
Awards
ix
Presidential Recognition Award
21st Richard C. Troutman MD DSc (Hon) Prize
The Presidential Recognition Award is a special award that honors the
recipient’s dedication and contributions to the field of refractive surgery
and to the ISRS.
The Troutman Prize recognizes the scientific merit of a young author
publishing in the Journal of Refractive Surgery. This prize honors Richard C. Troutman MD DSc (Hon).
Dr. Steinert is currently chair of the
department and director of the Gavin
Herbert Eye Institute at the University of
California, Irvine, where he holds joint
appointments as professor of clinical
ophthalmology and professor of biomedical engineering. He combines a consultative practice in cataract, refractive and
corneal surgery with teaching and translational laboratory research in these
Roger F Steinert MD
fields. He has authored or coauthored
four textbooks, including the definitive
text, Cataract Surgery, which is in its third edition. He has published over 120 peer-reviewed scientific journal articles and over
70 book chapters. Dr. Steinert is a member of the Executive
Committee of the American Society of Cataract and Refractive
Surgery (ASCRS) and became president of that society in April
2005, as well as chair of the Annual Program, a position he currently fills. He serves as associate editor of Ophthalmology, the
journal of the American Academy of Ophthalmology (the Academy), and he serves on the editorial board of the Journal of Cataract and Refractive Surgery. He has presented 10 named lectures,
including the Binkhorst Lecture at the 2004 meeting of the
ASCRS and the Barraquer Lecture at the 2008 Joint Meeting of
the Academy. Dr. Steinert serves as medical monitor of several
FDA trials. He holds seven U.S. and numerous international patents. He has received the Senior Honor Award of the Academy
and has been selected by his peers for inclusion in every edition
of Best Doctors in America and America’s Top Doctors. Ophthalmology Times named him one of the top 100 ophthalmologists in North America.
Dr. Steinert earned his medical degree from Harvard Medical
School, having graduated summa cum laude from Harvard College. He served his residency at Harvard Medical School’s Massachusetts Eye and Ear Infirmary and rose through the ranks of
the Harvard faculty until being recruited to UC Irvine.
Dr. Marcony R Santhiago graduated
from medical school in Rio de Janeiro
and completed electives in ophthalmology at Mount Sinai School of Medicine
in New York. After completion of his
residency at Piedade Hospital in Rio, he
went to a fellowship at the University of
São Paulo in Cataract and Refractive
Surgery under the supervision of Newton
Kara-Junior, Marcelo Netto and Samir J
Marcony R Santhiago
Bechara. At the same time he started the
doctoral program.
From 2009 to 2012 Dr. Santhiago did a postdoctoral fellowship under the supervision of Dr. Steven E Wilson at the refractive surgery department of the Cleveland Clinic.
Some of his awards include the Best of Show Award for Scientific Video at the 2011 Annual Meeting of the American Academy of Ophthalmology, the Preventing Blindness Award for Best
Paper at the 2010 Brazilian Congress of Ophthalmology, and the
Miguel Lafer Prize for Highest Scientific Production among all
physicians at the University of São Paulo 2010-2011. In 2012,
Dr. Santhiago was inducted as a member of ALUMNI-USP,
which recognizes individual merits among ophthalmologists at
the University of São Paulo.
A reviewer of several journals in ophthalmology, Dr. Santhiago’s research interests include basic research in corneal biology
as well as new developments in corneal topography, wavefront,
biomechanics and IOLs.
In 2012, he returned to Rio, where he now holds a faculty
position as a professor and head of the cataract and refractive
surgery department at the Federal University of Rio de Janeiro.
He is also a staff member at the University of São Paulo.
x
Faculty
No photo
available
Ahmed Abd El-Twab Abdou MD
Iqbal K Ahmed MD
Robert Edward T Ang MD
Assiut, Egypt
Lecturer, AUH, Egypt
Clinical Research Fellow
Vissum Alicante, Spain
Mississauga, ON, Canada
Assistant Professor
University of Toronto
Clinical Assistant Professor
University of Utah
Makati City, Philippines
Senior Ophthalmologist
Asian Eye Institute
Natalie A Afshari MD
Durham, NC
Professor of Ophthalmology and
Director of Cornea and Refractive
Surgery Fellowship
Duke University Eye Center
Amar Agarwal MD
Chennai, Tamilnadu, India
Chairman and Managing Director
Dr. Agarwal’s Group of Eye Hospitals
Gerd U Auffarth MD
Alicante, Spain
Professor of Ophthalmology
Miguel Hernandez University
Heidelberg, Germany
Chairman and Professor of
Ophthalmology
Department of Ophthalmology
University of Heidelberg
Noel A Alpins MD FACS
Scott D Barnes MD
Cheltenham, VIC, Australia
Associate Fellow
University of Melbourne
Fayetteville, NC
Chief, Warfighter Refractive Surgery
Fort Bragg, North Carolilna
Jorge L Alio MD PhD
Faculty Listing
No photo
available
Peter James Barry MD
Perry S Binder MD
Camille J R Budo MD
Dublin, Ireland
San Diego, CA
Medical Monitor
Abbott Medical Optics
Clinical Professor
Gavin Herbert Eye Institute
University of California, Irvine
Sint Truiden, Belgium
Associate Professor
University Eye Clinic, Maastricht
George Beiko MD
No photo
available
St Catharines, ON, Canada
Assistant Professor
McMaster University
Tenley N Bower MD
Milan, Italy
Medical Director
Carones Ophthalmology Center
Montreal, QC, Canada
Ophthalmology Resident
McGill Ophthalmology
No photo
available
Michael W Belin MD
Marana, AZ
University of Arizona Health Sciences
Cesar C Carriazo E MD
Rosa Braga-Mele MD
North York, ON, Canada
Associate Professor
University of Toronto
John P Berdahl MD
Sioux Falls, SD
Assitant Clinical Professor
University of South Dakota
Vance Thompson Vision
Barranquilla, AT, Colombia
Universidad del Norte
Scientific Director
Centro Oftalmólogico Carriazo
xi
xii
Faculty Listing
No photo
available
Daniel H Chang MD
Arturo S Chayet MD
Robert J Cionni MD
Bakersfield, CA
Cataract and Refractive Surgeon
Empire Eye and Laser Center
La Jolla, CA
Medical Director
Codet Vision Institute, Tijuana, Mexico
Salt Lake City, UT
Medical Director
The Eye Institute of Utah
No photo
available
David F Chang MD
Xiangjun Chen MD
Joseph Colin MD
Los Altos, CA
Clinical Professor of Ophthalmology
University of California, San Francisco
Adjunct Clinical Professor
Chinese University, Hong Kong
Tromsdalen, Norway
Researcher
SynsLaser Clinic
Bordeaux, France
Chairman, Ophthalmology Department
University of Bordeaux
Y Ralph Chu MD
Alan S Crandall MD
Bloomington, MN
Medical Director
Chu Vision Institute
Adjunct Associate Professor of
Ophthalmology
University of Minnesota
Salt Lake City, UT
Director, Glaucoma/Cataract
Moran Eye Center
University of Utah
Hong Kong, Hong Kong
Clinical Associate Professor of
Ophthalmology
The Chinese University Hong Kong
Ophthalmology
The University of Hong Kong
Faculty Listing
xiii
William W Culbertson MD
Steven J Dell MD
Burkhard Dick MD
Miami, FL
University of Miami
Austin, TX
Director of Refractive and Corneal
Surgery
Texan Eye
Medical Director
Dell Laser Consultants
Bochum, Germany
Chairman
University of Bochum
Chairman and Director
Center for Vision Science, Germany
Uday Devgan MD
Eric D Donnenfeld MD
Los Angeles, CA
Cataract and Refractive Surgeon and
Director
Devgan Eye Surgery
Chief of Ophthalmology
Olive View UCLA Medical Center
UCLA School of Medicine
Rockville Centre, NY
Founding Partner
Ophthalmic Consultants of Long Island
and Connecticut
New York University
Elizabeth A Davis MD
Bloomington, MN
Managing Partner
Minnesota Eye Consultants
James A Davison MD
Marshalltown, IA
Wolfe Eye Clinic
Deepinder K Dhaliwal MD
Pittsburgh, PA
Associate Professor of Ophthalmology
University of Pittsburgh School of
Medicine
Surgery
UPMC Eye Center, University of
Pittsburgh
Paul J Dougherty MD
Camarillo, CA
Medical Director
Dougherty Laser Vision
xiv
Faculty Listing
No photo
available
Richard J Duffey MD
William J Fishkind MD FACS
David A Goldman MD
Mobile, AL
Ophthalmologist
Premier Medical Eye Group
Tucson, AZ
University of Utah
Clinical Instructor of Ophthalmology
University of Arizona
Palm Beach Gardens, FL
Assistant Professor of Clinical
Ophthalmology
Bascom Palmer Eye Institute
Daniel S Durrie MD
Overland Park, KS
Professor of Clinical Ophthalmology and
Director of Refractive Surgery
University of Kansas Medical Center
Neil J Friedman MD
Gunther Grabner MD
Palo Alto, CA
Adjunct Clinical Associate Professor of
Ophthalmology
Stanford University School of Medicine
Salzburg, Austria
Paracelsus Medical University
Director, University Eye Clinic
Landeskrankenhaus, SALK
Damien Gatinel MD
José L Güell MD PhD
Paris, France
Assistant Professor of Ophthalmology
Rothschild Foundation
Barcelona, Spain
Universidad Autonoma de Barcelona
Surgery Unit
Instituto de Microcirugía Ocular de
Barcelona
Alaa M ElDanasoury MD
Jeddah, Saudi Arabia
Consultant Ophthalmologist
Magrabi Eye and Ear Hospital
Faculty Listing
xv
Farhad Hafezi MD PhD
David R Hardten MD
Peter S Hersh MD
Geneva, Switzerland
Professor and Chair of Ophthalmology
Geneva University Hospitals
Doheny Eye Institute, University of
Southern California
Minneapolis, MN
Adjunct Associate Professor of
Ophthalmology
Director of Fellowships and Research
Teaneck, NJ
Director, Cornea and Laser Eye Institute
Hersh Vision Group
University of Medicine and Dentistry,
New Jersey – New Jersey Medical
School
No photo
available
D Rex Hamilton MD
Thomas M Harvey MD
Los Angeles, CA
Associate Clinical Professor of
Ophthalmology
Jules Stein Eye Institute
University of California, Los Angeles
(UCLA)
Medical Director
UCLA Laser Refractive Center
Eau Claire, WI
Partner, Chippewa Valley Eye Clinic
Jesper Hjortdal MD
Aarhus C, Denmark
Aarhus University Hospital
Bonnie A Henderson MD
Sadeer B Hannush MD
Langhorne, PA
Attending Surgeon
Cornea Service, Wills Eye Institute
Jefferson Medical College
Dover, MA
Partner, Ophthalmic Consultants of
Boston
Assistant Clinical Professor
Harvard Medical School
Kenneth J Hoffer MD FACS
Santa Monica, CA
Clincal Professor of Ophthalmology
Surgeon
St. Mary’s Eye Center, Santa Monica
xvi
Faculty Listing
Jack T Holladay MD MSEE FACS
John A Hovanesian MD
W Bruce Jackson MD FRCSC
Bellaire, TX
Baylor College of Medicine, Houston
Laguna Hills, CA
Clinical Instructor
Ottawa, ON, Canada
University of Ottawa
Simon P Holland MD
Vancouver, BC, Canada
University of British Columbia
David Huang MD PhD
Portland, OR
Weeks Professor of Ophthalmic
Research
Oregon Health & Science University
Mike P Holzer MD
Heidelberg, Germany
Vice Chairman and Associate Professor
Soosan Jacob FRCS
Chennai, Tamilnadu, India
Senior Consultant Ophthalmologist
Dr. Agarwal’s Group of Eye Hospitals
Choun-ki Joo MD
Osama I Ibrahim MD PhD
Alexandria, Egypt
Professor of Ophthalmology, Chief
Cornea and Refractive Surgery, and
President, Alexandria University
Seoul, Korea
The Catholic University of Korea
Athens, Greece
New York University Medical College
Faculty Listing
xvii
Terry Kim MD
Douglas D Koch MD
Athens, Greece
Medical Doctor
Orasis Eye Center
Head of Refractive Department
Durham, NC
Duke University School of Medicine
Director of Ophthalmology Fellowship
Programs
Cornea and Refractive Surgery
Duke University Eye Center
Houston, TX
Professor and The Allen, Mosbacher and
Law Chair in Ophthalmology
Cullen Eye Institute
Baylor College of Medicine
No photo
available
Sumitra S Khandelwal MD
Minneapolis, MN
Resident, Emory University
Thomas Kohnen MD PhD FEBO
Stephen D Klyce PhD
Port Washington, NY
Adjunct Professor of Ophthalmology
Mount Sinai School of Medicine
Frankfurt, Germany
Goethe University
Aylin Kiliç MD
Ankara, Turkey
Medical Doctor
Dunya Eye Hospital
Ronald R Krueger MD
Michael C Knorz MD
Mannheim, Germany
Medical Faculty, Mannheim
Cleveland, OH
Medical Director, Refractive Surgery
Cole Eye Institute, Cleveland Clinic
Cleveland Clinic, Lerner College of
Medicine
Case Western Reserve University
xviii
Faculty Listing
No photo
available
George D Kymionis MD PhD
Parag A Majmudar MD
Edward E Manche MD
Heraklion, Greece
Lecturer of Ophthalmology
University of Crete
South Barrington, IL
Rush University Medical Center
Palo Alto, CA
Stanford University School of Medicine
Michael A Lawless MD
John Males MBCB FRANZO
Stephanie Jones Marioneaux MD
Chatswood, NSW, Australia
Medical Director
Vision Eye Institute
Clinical Senior Lecturer
Sydney University Medical School
Sydney, NSW, Australia
University of Sydney
Sydney Eye Hospital
Macquarie University Hospital
Chesapeake, VA
American Academy of Ophthalmology
Eastern Medical of Virginia
Richard Lindstrom MD
Bloomington, MN
Founder and Attending Surgeon
Adjunct Professor Emeritus
University of Minnesota, Department of
Ophthalmology
John Marshall PhD
Robert K Maloney MD
Los Angeles, CA
Director, Maloney Vision Institute
Hants, England
Institute of Ophthalmology
University College London
Faculty Listing
Samuel Masket MD
Zoltan Nagy MD
Louis D Skip Nichamin MD
Los Angeles, CA
David Geffen School of Medicine
Budapest, Hungary
Second Department of Ophthalmology
Semmelweis University
Brookville, PA
Medical Director
Laurel Eye Clinic
Lynbrook, NY
Cornea, Cataract and Refractive Surgery
Ophthalmic Consultants of Long Island,
Lynbrook, NY
Alejandro Navas MD
Mexico City, DF, Mexico
Institute of Opthalmology “Conde de
Valenciana”
Thomas A Oetting MD
Iowa City, IA
Professor of Clinical Ophthalmology
University of Iowa
Robert H Osher MD
Jodhbir S Mehta MBBCH BS
Singapore, Singapore
Associate Professor
Duke-NUS Graduate Medical School
Marcelo V Netto MD
São Paulo, SP, Brazil
MD, Cornea and Refractive Surgery
Staff
University of São Paulo
Cincinnati, OH
University of Cincinnati School of
Medicine
Medical Director Emeritus
Cincinnati Eye Institute
xix
xx
Faculty Listing
Ioannis G Pallikaris MD
Yaron S Rabinowitz MD
Christopher J Rapuano MD
Heraklion, Greece
University of Crete
Beverly Hills, CA
Director of Ophthalmology Research
Cedars Sinai Medical Center
School of Medicine
Philadelphia, PA
Chief, Cornea Service
Wills Eye Institute
Jefferson Medical College of Thomas
Jefferson University
Arturo J Ramirez-Miranda MD
Sherman W Reeves MD MPH
Mexico City, Mexico
International Fellow
Plymouth, MN
Partner
Adjunct Assistant Professor
Matteo Piovella MD
Monza, Italy
Founder and Scientific Director
CMA, Centro Microchirurgia
Ambulatoriale
Louis E Probst MD
Westchester, IL
Medical Director
TLC, The Laser Eye Center
Atlanta, GA
Emory University
Dan Z Reinstein MD
London, England
Medical Director
London Vision Clinic
Faculty Listing
xxi
Olivier Richoz MD
Diana F Rodriguez-Matilde MD
Mahipal S Sachdev MBBS
La Chaux-de-Fonds, Switzerland
Medical Resident
Geneva University Hospitals
Geneva, Switzerland
Mexico City, Mexico
Cornea Fellow
Instituto de Oftalmología, Fundación
Cornea de Valencia
New Delhi, India
Chairman and Medical Director
Centre for Sight Group of Eye Hospitals
Robert P Rivera MD
Sandy, UT
Director of Clinical Research
Hoopes Vision
Emanuel S Rosen MD
Manchester, England
Director, Rosen Eye Clinic
Visiting Professor
Department of Vision Sciences
University of Manchester
Marcony R Santhiago MD
Rio de Janeiro, RJ, Brazil
Federal University of Rio de Janeiro
Karolinne M Rocha MD
Shaker Heights, OH
Cleveland Clinic Foundation
Cole Eye Institute
Kenneth J Rosenthal MD FACS
Great Neck, NY
Asociate Professor of Ophthalmology
University of Utah Medical School
Surgeon Director
Rosenthal Eye Surgery
San Diego, CA
University of San Francisco
xxii
Faculty Listing
Barry S Seibel MD
Michael E Snyder MD
Jason E Stahl MD
Los Angeles, CA
Clinical Assistant Professor of
Ophthalmology
Geffen School of Medicine
Cincinnati, OH
Faculty and Board of Directors
Cincinnati Eye Institute
Volunteer Assistant Professor
University of Cincinnati
Kansas City, MO
Cataract and Refractive Surgeon
Durrie Vision
Walter J Stark MD
Theo Seiler MD PhD
Felipe A Soria MD
Zurich, Switzerland
University of Zurich
Chairman
IROC Zurich
Alicante, Spain
Ophthalmologist
Vissum Corporacion Alicante
Baltimore, MD
Boone Pickens Professor of
Ophthalmology
Johns Hopkins University
The Wilmer Eye Institute
Director, Corneal and Cataract Services
The Johns Hopkins University
Leopoldo Spadea MD
Stephen G Slade MD FACS
Houston, TX
Surgeon, Slade & Baker Vision
L’Aquila, Italy
University of L’Aquila
Roger F Steinert MD
Irvine, CA
Irving H Leopold Professor and Chair of
Ophthalmology
Gavin Herbert Eye Institute
University of California, Irvine
Faculty Listing
Pavel Stodulka MD PhD
Vance Michael Thompson MD
Harvey S Uy MD
Zlin, Czech Republic
Head Surgeon
Gemini Eye Clinic
Sioux Falls, SD
University of South Dakota School of
Medicine
Ophthalmology
University of the Philippines
Minoru Tomita MD PhD
Pravin Vaddavalli MD
Tokyo, Japan
Executive Medical Director
Shinagawa LASIK Center
Hyderabad, Andhra Pradesh, India
Associate Ophthalmologist
L V Prasad Eye Institute
Dan B Tran MD
Jan A Venter MD
Long Beach, CA
Medical Director
Coastal Vision Medical Group
London, England
Medical Director
Optical Express
Paolo Vinciguerra MD
Miami, FL
Director of Cornea
Center For Excellence In Eye Care
Milan, Italy
Ophthalmology Department
Istituto Clinico Humanitas Rozzano
Karl G Stonecipher MD
Greensboro, NC
Medical Director
TLC Greensboro
R Doyle Stulting MD PhD
Atlanta, GA
Director, Stulting Research Center
Woolfson Eye Institute
Gustavo E Tamayo MD
Bogota, DC, Colombia
Director, Bogota Laser Refractive
Institute
Member, Executive Committee ISRS
xxiii
xxiv
Faculty Listing
John Allan Vukich MD
George O Waring IV MD
Sonia H Yoo MD
Madison, WI
Assistant Clinical Professor
University of Wisconsin, Madison,
School of Medicine
Partner, Davis Duehr Dean Center for
Refractive Surgery
Charleston, SC
Assistant Professor of Ophthalmology,
Medical University of South Carolina
Storm Eye Institute
Medical Director
Magill Vision Center
Miami, FL
University of Miami Miller School of
Medicine
R Bruce Wallace MD
Alexandria, LA
Louisiana State University Medical
School
Tulane Medical School
Steven E Wilson MD
George O Waring III MD FACS
Helen K Wu MD
Atlanta, GA
Emory University
Ophthalmolgist, Eye 1st Vision and
Laser
Chestnut Hill, MA
Tufts University School of Medicine
New England Eye Center
Cleveland, OH
Professor of Ophthalmology, Staff
Refractive and Corneal Surgeon
The Cole Eye Institute
The Cleveland Clinic Foundation
Roberto Zaldivar MD
Mendoza, Argentina
President, Zaldivar Institute
Member and Former Founder
SACRyC (Argentine Society of
Refractive Surgery and Cornea)
xxv
Refractive Surgery 2012: The Era of Lasers and Lenses
The Annual Meeting of the International Society of Refractive Surgery
Sponsored by ISRS
Schedule at a Glance
Friday, Nov. 9
Type
8 AM
9 AM
10 AM
11 AM
12 PM
Hall B
Sessions
8:00–10:23 AM; break; 10:53 AM–12:39 PM
Grand Ballroom
S100ab
Free Papers
1 PM
11:18 AM–
12:36 PM
2 PM
3 PM
4 PM
5 PM
1:54–3:25 PM; break;
4:05–5:05 PM
2:04–3:20 PM; break;
4:05–5:11 PM
Saturday, Nov. 10
Hall B
Sessions
8:00–10:04 AM; break; 10:59 AM–12:34 PM
1:49–3:30 PM; break;
4:06–5:24 PM
FRIDAY, NOVEMBER 9
7:00 AM REGISTRATION/ MATERIAL PICKUP/ CONTINENTAL BREAKFAST
8:00 AM Welcome and Opening Remarks
Section I: Cornea Point-Counterpoint
Moderators: Stephen D Klyce PhD*, George D Kymionis MD PhD
Panelists: Joseph Colin MD*, Deepinder K Dhaliwal MD, A John Kanellopoulos MD*
Topic I: Thin Corneas
8:05 AM
Point: No LASIK in Thin Corneas R Doyle Stulting MD PhD*
1
8:13 AM
Counterpoint: No Lower Limit for Thin Corneas
William B Trattler MD*
2
8:21 AM
Discussion
Topic II: Dry Eye
8:26 AM
Point: No Laser in Patients With Dry Eye Christopher J Rapuano MD*
3
8:34 AM
Counterpoint: Selective Laser in Patients With Dry Eye Eric D Donnenfeld MD*
5
8:42 AM
Discussion
Topic III: Monovision
8:47 AM
Point: Monovision Is the Way for Laser Vision Correction Dan Z Reinstein MD*
7
8:55 AM
Counterpoint: No Monovision for Laser Vision Correction
Osama I Ibrahim MD PhD*
9
9:03 AM
Discussion
Topic IV: Corneal Presbyopia Correction
9:08 AM
Point: Corneal Inlays for Corneal Presbyopia Correction
Damien Gatinel MD*
10
9:16 AM
Counterpoint: Corneal Laser for Presbyopia Correction
Gustavo E Tamayo MD*
12
9:24 AM
Discussion
* Indicates that the presenter has financial interest.
No asterisk indicates that the presenter has no financial interest.
David R Hardten MD*
Michael C Knorz MD*
xxvi
Program Schedule
Section II: Cornea Video Complications
Moderators: Alaa M ElDanasoury MD*, Sonia H Yoo MD*
9:29 AM PRK and LASEK Technique
Parag A Majmudar MD*
14
9:36 AM Pupil Tracking, Centration, and Iris Registration
Louis E Probst MD*
15
9:43 AM LASIK Enhancement Techniques
Richard L Lindstrom MD*
16
9:50 AM Suction Loss
Pravin Vaddavalli MD*
17
9:57 AM LASIK Striae Management Ronald R Krueger MD*
18
10:04 AM Femtosecond LASIK Complications
John So-Min Chang MD*
19
10:11 AM Discussion
10:23 AM REFRESHMENT BREAK
ISRS President’s Update
10:53 AM
ISRS President’s Update
Amar Agarwal MD*
10:54 AM ISRS 2012 Awardees (Barraquer Award, Casebeer Award, Kritzinger Memorial Award, Founder’s Award, Lans Award,
Lifetime Achievement Award, Troutman Prize, Presidential Award)
Amar Agarwal MD*
Keynote Lecture
11:08 AM
Corneal Presbyopic Surgery Sonia H Yoo MD*
20
Section III: Corneal Crosslinking
Moderators: Vikentia Katsanevaki MD, Marguerite B McDonald MD*
11:18 AM Riboflavin Penetration Into the Cornea
Jesper Hjortdal MD*
21
11:26 AM Crosslinking: Epithelium On or Off?
Leopoldo Spadea MD
23
11:34 AM Long-term Results and Complications in Keratoconus
24
11:42 AM Long-term Results and Complications in Post-LASIK Ectasia
Theo Seiler MD PhD*
26
11:50 AM Combined Crosslinking and Laser Ablation
A John Kanellopoulos MD*
27
11:58 AM Crosslinking in Pedriatic Patients
Paolo Vinciguerra MD*
44
12:06 PM Rationale and Results of Accelerated Corneal Crosslinking John Marshall PhD*
47
12:14 PM Crosslinking Should Not Be Combined With Primary LASIK
Perry S Binder MD*
48
12:22 PM Discussion
12:34 PM Advocating for Patients
Stephanie Jones Marioneaux
MD52
Free Paper Session I
Grand Ballroom S100ab
Moderator: George O Waring III MD FACS*
11:18 AM
Introduction
George O Waring III MD FACS*
11:20 AM Transepithelial and Epithelium-off Riboflavin-UVA Crosslinking: Biological and Biomechanical Responses in Rabbits
Steven E Wilson MD*
54
11:25 AM
Effect of Collagen Crosslinking on the Limbal Stem Cells
Olivier Richoz MD
54
Program Schedule
xxvii
11:30 AM
Results of Collagen Crosslinking With Riboflavin in Children With Progressive Keratoconus
Mahipal S Sachdev MBBS*
54
11:35 AM
Forme Fruste Keratoconus Detection by Corneal Epithelial Thickness Mapping With OCT
David Huang MD PhD*
55
11:40 AM
Management of Ectasia Following Corneal Refractive Surgery
Jan A Venter MD
55
11:45 AM
Outcomes of Corneal Collagen Crosslinking for Treatment of Keratoconus and Ectasia After LASIK
55
11:50 AM
Discussion
11:58 AM
Topography-Guided Photorefractive Keratectomy and Crosslinking for Ectasia After LASIK
Simon P Holland MD*
56
12:03 PM
Collagen Crosslinking and Topography-Guided Customized Ablation Treatment for Keratoconus and Post-LASIK Ectasia
Tenley N Bower MD
56
12:08 PM
Five-Year Outcomes of Intracorneal Ring Segments for the Treatment of Keratoconus: Stability Analysis
Jorge L Alio MD PhD*
56
12:13 PM
Effect of Hinge Location on Dry Eye Symptoms and High-Order Aberration Following Femtosecond Laser-Assisted LASIK
Choun-ki Joo MD
57
12:18 PM
Initial Results of a New Wavefront-Guided LASIK Procedure
Steven C Schallhorn MD*
57
12:23 PM
Phakic IOL Explantation: Results and Outcomes in 140 Cases Felipe A Soria MD
57
12:28 PM
Discussion
12:36 PM
LUNCH
Daniel S Durrie MD*
58
60
Keynote Lecture
1:54 PM
Presbyopic Lenses: Where Are We Headed? Section IV: Presbyopia
Moderators: Roger F Steinert MD*, William B Trattler MD*
2:04 PM Corneal Intrastromal Femtosecond Laser Treatment for Presbyopia: Indications and Results
Mike P Holzer MD*
2:12 PM Corneal Excimer Laser Ablations
W Bruce Jackson MD FRCSC* 61
2:20 PM Corneal Ablations: What About Reversability?
Michael C Knorz MD*
65
2:28 PM Corneal Inlays
John Allan Vukich MD*
66
2:36 PM Simulataneous LASIK and Implanatation of an Intracorneal Inlay
Minoru Tomita MD PhD*
67
2:44 PM Multifocal IOLs
70
2:52 PM Accommodating IOLs
Burkhard Dick MD*
74
3:00 PM How to Center Corneal Inlays
Francesco Carones MD*
75
3:08 PM Discussion
Free Paper Session II
Moderator: Vance Michael Thompson MD*
2:04 PM
Preliminary Results From a New Aspheric Apodized Diffractive Multifocal IOL With a +2.5 D Add Power
Francesco Carones MD*
77
2:09 PM
Experience With a Laser for Cataract Surgery
Burkhard Dick MD*
77
xxviii
Program Schedule
2:14 PM
First 1000 Cases of Laser-Assisted Cataract Surgery Experiences
Pavel Stodulka MD PhD*
77
2:19 PM
Refractive IOL Outcomes of Femtosecond Laser Cataract Surgery vs. Conventional Phacoemulsification
Dan B Tran MD*
78
2:24 PM
Visual Outcome, Efficacy, Safety, and Surgical Efficiency of Femtosecond Laser Refractive Lens Surgery: 45 Cases
Ahmed Abd El-Twab Abdou
MD
78
2:29 PM
High-resolution Scheimpflug Images Guide: Phacoemulsification Technique Selection During Laser-Assisted Cataract Surgery
Harvey S Uy MD*
78
2:34 PM
Discussion
2:42 PM
Initial Outcomes of Intrastromal Femtosecond Arcuate Incisions
78
2:47 PM
Femtosecond Laser Astigmatic Keratotomy in Patients With Mixed Astigmatism After Previous Refractive Surgery
Jan A Venter MD
79
2:52 PM
Vision and Spectacle Independence After Bilateral Implantation of +3D Diffractive Toric and Nontoric Multifocal IOLs
Michael C Knorz MD*
79
2:57 PM
Prospective Comparison of 3 Presbyopia-Correcting IOLs
Robert Edward T Ang MD* 79
3:02 PM
Laser Refractive Lens Surgery: The Value Proposition From
My Perspective as a Patient
Daniel S Durrie MD*
79
3:07 PM
Multicenter Clinical Evaluation of Hydrophobic Aspheric Diffractive 1-Piece Multifocal IOL
Elizabeth A Davis MD*
80
3:12 PM
Discussion
Break With the Experts
Hall B
3:25 PM – 4:00 PM
Cataract and IOL Complications
Rosa Braga-Mele MD*
Michael E Snyder MD*
Collagen Crosslinking
Farhad Hafezi MD PhD*
Peter S Hersh MD*
Corneal Inlays
Robert P Rivera MD*
Elevation Corneal Tomography
Michael W Belin MD*
D Rex Hamilton MD*
Laser Refractive Lens Surgery
Robert J Cionni MD*
Neil J Friedman MD*
Karl G Stonecipher MD*
Intracorneal Rings
Joseph Colin MD*
Laser Vision Correction Enhancements
Natalie A Afshari MD*
Phakic IOLs
Scott D Barnes MD*
Jason E Stahl MD*
Planning IOL Powers
Kenneth J Hoffer MD FACS*
Jack T Holladay MD MSEE FACS*
Presbyopic IOL Pearls
Y Ralph Chu MD*
Steven J Dell MD*
Toric IOL Pearls
James A Davison MD*
Soosan Jacob MBBS
Program Schedule
xxix
Section V: European Society of Cataract and Refractive Surgery (ESCRS) Symposium:
Corneal Refractive Surgery—Advanced Techniques
Moderators: Peter James Barry MD, Jose L Guell MD PhD*
4:05 PM
All Femtosecond Laser LASIK: ReLEx-SMILE
Jose L Guell MD PhD*
81
4:12 PM
Customized Transepithelial No-Touch Refractive and Therapeutic Procedures
Xiangjun Chen MD
86
Presbyopic Intracorneal Lenses: New Projects
4:19 PM
Pinhole
Gunther Grabner MD*
88
4:26 PM
Hydrogel: Swiss Project
Thomas Kohnen MD PhD
FEBO*91
4:33 PM
Hydrogel: Flexivue Project
Ioannis G Pallikaris MD*
92
4:40 PM
Combined PRK-Collagen Crosslinking in Keratoconus Suspects and Forme Fruste
93
4:47 PM
Discussion
5:05 PM
Closing Remarks
David R Hardten MD*
Michael C Knorz MD*
Free Paper Session III
Moderator: Noel A Alpins MD FACS*
4:05 PM
Accuracy of Corneal Astigmatism Prediction With Various Devices
Douglas D Koch MD*
94
4:10 PM
New Excimer Laser Custom Strategy: Asymmetric Centration Combining Pupil and Corneal Vertex Information
Paolo Vinciguerra MD*
94
4:15 PM
A Measure of Corneal Astigmatism That Corresponds to Manifest Refractive Cylinder Corneal Topographic Astigmatism (CorT)
Noel A Alpins MD FACS*
94
4:20 PM
Three-Dimensional Spectral-Domain OCT Analysis of a Prospective Contralateral Femtosecond LASIK Study for Myopia
95
4:25 PM
Predictability of Nanojoule Femtosecond Laser Flap Thicknesses Measured With Corneal Waveform Ultrasound Technology
Paul J Dougherty MD*
95
4:30 PM
Refractive, Visual, and Clinical Outcomes of Femtosecond Lenticule Extraction FLEx vs. Femto-LASIK Treatments for Myopia
Diana F Rodriguez-Matilde
MD
95
4:35 PM
Discussion
4:43 PM
Comparison of Recovery of Central Corneal Sensation After ReLEx Small-Incision Lenticule Extraction and LASIK
Dan Z Reinstein MD
96
4:48 PM
Small-Incision Lenticule Extraction Procedure for the Correction of Myopia and Astigmatism: Six-Month Results
Arturo J Ramirez-Miranda
MD
96
4:53 PM
Small-Incision Lenticule Extraction for Myopia in 1000 Eyes: Predictors for Reproducibility, Efficacy, and Safety
Jesper Hjortdal MD*
96
4:58 PM
A Prospective Comparison of Wavefront-Guided vs. Wavefront-Optimized LASIK Clinical Outcomes
Edward E Manche MD*
97
5:03 PM
Discussion
5:11 PM
ADJOURN
5:30 – 7:30 PM
ISRS Awardee, Faculty and Member Reception, Hyatt McCormick Place
xxx
Program Schedule
SATURDAY, NOVEMBER 10
7:00 AM
CONTINENTAL BREAKFAST
8:00 AM Opening Remarks
Section VI: Lens Point-Counterpoint
Moderators: Robert K Maloney MD*, Emanuel S Rosen MD*
Panelists: George Beiko MD*, Mateo Piovella MD*, Kenneth J Rosenthal MD FACS*
Topic I: Astigmatism Correction
8:02 AM Point: Limbal Relaxing Incisions
Louis D Skip Nichamin MD*
98
8:07 AM Counterpoint: Toric IOLs
John A Hovanesian MD*
99
8:12 AM Discussion
Topic II: Deficient Capsules
8:17 AM Point: Suturing a Posterior Chamber IOL Is the Way to Go
Walter J Stark MD*
100
8:21 AM Counterpoint: Gluing a Posterior Chamber IOL Is the Way to Go
Sadeer B Hannush MD
103
8:25 AM Counterpoint: Anterior Chamber IOL Is the Way to Go
Camille J R Budo MD*
104
8:29 AM Discussion
Topic III: Hard Brown Cataracts
8:34 AM Point: Phaco Uday Devgan MD*
105
8:39 AM Counterpoint: Small-Incision Manual Cataract Surgery Bonnie A Henderson MD*
106
8:44 AM Discussion
Topic IV: Premium IOLs
8:49 AM Point: Accommodating IOL
R Bruce Wallace MD*
107
8:54 AM Counterpoint: Multifocal IOL
Terry Kim MD*
108
8:59 AM Discussion
Section VII: Lens Complications—Video Presentations Moderators: Amar Agarwal MD*, William J Fishkind MD FACS*
9:04 AM Subluxation and Rings
Thomas A Oetting MD
110
9:11 AM Capsular Defects
Iqbal K Ahmed MD*
112
9:18 AM Glued IOL
Roger F Steinert MD*
113
9:25 AM Lens Nightmare
Amar Agarwal MD*
114
9:32 AM Premium IOL Exchange
David F Chang MD*
115
9:39 AM Refractive Surprise
Robert H Osher MD*
116
9:46 AM
Iris Woes
Samuel Masket MD*
117
9:53 AM Discussion
10:04 AM REFRESHMENT BREAK and JOINT MEETING EXHIBITS
David R Hardten MD*
Michael C Knorz MD*
Program Schedule
xxxi
Keynote Lecture
10:59 AM
Overview of Phakic IOLs Thomas Kohnen MD PhD
FEBO*119
Section VIII: The Journal of Refractive Surgery’s Hot, Hotter, Hottest: Late Breaking News
Moderator: J Bradley Randleman MD, Roberto Zaldivar MD*
11:09 AM Introduction of the Troutman Prize
11:14 AM Short-term Cell Death and Inflammation After Intracorneal Inlay Implantation in Rabbits
11:29 AM
Update on Therapeutic Bandage Lenses for Surface Ablation
Marguerite B McDonald
MD*122
11:37 AM Light-Adjustable IOLs
Arturo S Chayet MD*
123
11:45 AM Toric IOLs for Keratoconus
Alejandro Navas MD
124
11:53 AM Advances in Translational Science in Refractive Surgery Farhad Hafezi MD PhD*
126
12:01 PM Presbyopic Inlays
Ioannis G Pallikaris MD*
127
12:09 PM Trends in Refractive Surgery Survey
Richard J Duffey MD
128
12:17 PM Discussion
12:29 PM JRS Qwikfacts
12:34 PM LUNCH and JOINT MEETING EXHIBITS
121
Keynote Lecture
1:49 PM
The Future of Laser Refractive Lens Surgery Section IX: Laser Refractive Lens Surgery Symposium
Moderators: David R Hardten MD*, Helen K Wu MD*
Panelists: Francesco Carones MD*, Alan S Crandall MD*, Michael A Lawless MD*
1:59 PM Which Patients Truly Benefit From Laser Refractive Lens Surgery?
Michael C Knorz MD*
131
2:07 PM Technique Pearls for Success in Laser Refractive Lens Surgery
William W Culbertson MD*
133
2:15 PM Spherical Refractive Accuracy: More Accurate, and Only Small A-Constant Optimization
Robert J Cionni MD*
134
2:23 PM Spherical Refractive Accuracy: Requires A-Constant Optimization
Jack T Holladay MD MSEE
FACS*135
2:31 PM Laser Refractive Lens Surgery: Advantages and Use for Complicated Cases
Barry S Seibel MD*
2:39 PM IOL Centration: Capsule Size and Shape, or IOL Position at End of Surgery? Daniel H Chang MD*
138
2:47 PM Precision in Optics: Why Laser Refractive Lens Surgery Is So Critical
Zoltan Nagy MD*
140
2:55 PM Imaging Accuracy Is Critical in Laser Refractive Lens Surgery
Gerd U Auffarth MD*
141
3:03 PM Astigmatic Keratotomy in Laser Refractive Lens Surgery: Comparison of Simultaneous and Separate Surgeries
Eric D Donnenfeld MD*
142
3:11 PM
Can Laser Refractive Lens Surgery Really Work for You and
Your Practice?
Stephen G Slade MD FACS*
146
3:19 PM Discussion
3:30 PM REFRESHMENT BREAK and JOINT MEETING EXHIBITS
Michael A Lawless MD*
129
137
xxxii
Program Schedule
Section X: Foundations of Refractive Surgery
Moderators: Sherman W Reeves MD MPH*, Vance Michael Thompson MD*, George O Waring IV MD*
Topic I: Decision Making in Refractive Surgery
4:06 PM Corneal or Lens Refractive Surgery? George O Waring IV MD*
147
4:14 PM Basics of Tomography and Topography
Marcelo V Netto MD*
148
4:22 PM Which IOL to Use? Sherman W Reeves MD
MPH*150
Topic II: Complications and Unhappy Patients
4:30 PM Managing LASIK Complications
Aylin Kilic MD
152
4:38 PM Managing the Unhappy Refractive IOL Patient
David A Goldman MD*
155
Topic III: Expanding Your Refractive Toolkit
4:46 PM Refractive Lens Exchange
John P Berdahl MD*
157
4:54 PM Phakic IOLs: Tips and Techniques Thomas M Harvey MD*
158
5:02 PM Small-Incision Corneal Lenticule Extraction Jodhbir S Mehta MBBCH
BS*159
5:10 PM Discussion
5:22 PM Closing Remarks
5:24 PM ADJOURN
David R Hardten MD*
Michael C Knorz MD*
Point: No LASIK in Thin Corneas
Notes
1
2
Counterpoint: No Lower Limit for Thin Corneas
William Trattler MD
Why would thin corneas but normal topography place a patient
interested in LASIK at an increased risk for a postoperative complication? For most surgeons, there is a thought that patients
with thin corneas (even with a normal topography) may have a
weaker cornea, and therefore place the patient at increased risk
for post-LASIK ectasia.
However, this theoretical concern has actually not been seen
in prospective studies of LASIK. Over the past decade, there
have been numerous peer-reviewed articles (see Table 1) on the
results of LASIK in patients with thin corneas (less than 500
microns). One key safety measure in many of these studies was
the measurement of intraoperative pachymetry to ensure an
adequate residual stromal bed thickness after the laser ablation.
More recently, Steve Schallhorn presented the results from a
large cohort of more than 400,000 eyes that underwent LASIK
or PRK from January 2007 to April 2011. LASIK patients had
surgery with either mechanical microkeratomes (just under 40%)
or femto laser (over 60%). In this cohort, close to 60 (approximately 1 in 3500 patients) experienced post-LASIK ectasia.
Retrospective review demonstrates that abnormal topography
was the most important risk factor. Looking at corneal thickness:
approximately 95% of the more than 400,000 patients had a
preop corneal thickness of 500 microns or higher, while 90% of
ectasia patients had a preop corneal thickness of 500 microns or
higher. While there was a slightly higher percentage percentage
of corneas that were under 500 microns with ectasia, many of
these had clear abnormal topographic findings. Further, since
90% of ectasia patients had a preop corneal thickness of 500
microns or more, it would probably make more sense to exclude
patients with corneal thickness above 500 microns.
All joking aside, the fact is that focusing on thin corneas with
normal topographies alone does not reduce the risk of postLASIK ectasia for our LASIK patients.
In contrast, patients with abnormal topography are at
increased risk for post-LASIK ectasia, regardless of their preoperative corneal thickness.
Figure 1
Of course, the biggest challenge is topography interpretation.
While LASIK in thin corneas and normal topographies appears
to be safe, the key step is actually interpreting the topography.
Besides looking for asymmetry in the topography, it is also
important to look for symmetry between eyes. Further, software
for screening, developed by Michael Belin and Renato Ambrosio,
may be helping at identifying eyes that may be at increased risk
for ectasia, regardless of the preoperative corneal thickness.
In summary: the peer-reviewed literature has found that
LASIK in thin corneas with normal topography and intraoperative pachymetry measurements appears to be both safe and effective, and does not appear to carry an increased risk of ectasia
compared to LASIK in patients with thicker corneas.
While there are some experts who may advise that LASIK
should not be performed in thin corneas, it is important to
understand that there is no prospective scientific evidence that
there is an increased risk for ectasia when the preoperative
topography is normal and the intraoperative corneal thickness is
measured.
Please feel free to email me at [email protected] if there
are questions.
Table 1. Thin Cornea and the LASIK Literature: Prospective LASIK Outcomes in Thin Corneas
Study
N
Range of
Pachymetry
Follow-up
(months)
Outcome
Kremer, J Cataract Refract Surg.,
2006
98
456 to 498
36
LASIK safe in eyes with thin corneas
Caster, J Refract Surg., 2007
109
452 to 500
12 to 63
No evidence of postop keratectasia
Kymionis, Am J Ophthalmol.,
2007
56
470 to 498
12 to 36
Binder, J Cataract Refract Surg.,
2007
117
450 to 500
> 12 mean 27
No eye with a preop corneal thickness ≤ 500 μm developed ectasia
Zhonghua Ke
Za Zhi, 2006
39
450 to 500
> 12
Djodeyre, J Cataract Refract
Surg., 2012
40
440 to 469
> 60
LASIK safe in eyes with thin corneas and normal preoperative
topography
3
Point: No Laser in Patients With Dry Eye
There is little doubt that laser corneal refractive surgery causes
some type of ocular surface damage and untoward symptoms in
many patients.1,2 The symptoms range from mild dryness and
foreign body sensation to moderate discomfort and, rarely, to
debilitating pain. Other symptoms include fluctuating vision,
shadow vision, and monocular diplopia. Dry eye after refractive surgery is also associated with refractive regression.3 While
laser corneal refractive surgery is highly safe and effective for the
vast majority of people, in the small minority who develop these
symptoms, when severe, these patients can be the most unhappy
in your entire practice. The $64,000 (or $64 million?) question is
how to avoid this situation.
Unfortunately, the exact cause of these symptoms remains
unclear. Is it dry eye? Is it a neurotrophic keratopathy? Is it a corneal neuropathy? Is it something else??
What do we know? One study retrospectively reviewed 190
eyes 1 week and 1, 3, and 6 months after LASIK and found that
chronic dry eye signs and symptoms persisted greater than 6
months in 20% of eyes. Female sex and higher refractive correction were statistically significantly associated with dryness.4 In
an earlier study, post-LASIK dry eye was found in approximately
50% of eyes at 1 week, 40% at 1 month, 20% at 3 months,
and 25% at 6 months. These authors found similar percentages
for superior hinged femtosecond laser flaps and nasal-hinged
mechanical microkeratome flaps.5
Another prospective fellow eye study in 51 patients showed
no difference in self-reported dry eye symptoms when using a
femtosecond laser than a mechanical microkeratome. They did
find increased dry eye symptoms in women but no correlation
with ablation depth.6 However a previous study found more
dry eye symptoms in eyes with mechanical microkeratome flaps
(mean thickness 131 microns) than femtosecond laser flaps
(mean thickness 111 microns), although they found no correlation with ablation depth.7 Additionally, when using a femtosecond laser to create the LASIK flap, there does not seem to a
difference in dry eye signs or symptoms when using a superior or
temporal hinge or when using a 45-degree to 90-degree hinge or
when using a 100 or a 130 micron thickness flap.8,9
Forty-eight eyes were evaluated for dry eye signs and symptoms before and 1 week and 1, 2, 3, 6, 12, and 16 months postoperatively. The authors found corneal and conjunctival sensitivity were decreased, and symptom severity scores were increased 1
week and 12 and 16 months postoperatively (all statistically significant).10 Another study evaluated tear secretion and tear film
instability after LASIK and PRK. They found lower Schirmer and
tear break-up times (TBUT) scores and a greater change in tear
osmolarity in the LASIK eyes than the PRK eyes.11
A study of 20 eyes of patients who had undergone LASIK for
high myopia (-9 to -14 D) 2 to 5 years prior showed statistically
significantly greater dry eye symptoms compared to age-matched
controls, although they could not demonstrate objective signs of
tear insufficiency or hypoesthesia and proposed the symptoms
may be due to a corneal neuropathy rather than directly from
dry eyes.12
Corneal neuropathy and dry eye may certainly be related.
Comparing 21 dry eye patients with 20 healthy volunteers using
noncontact esthesiometry and confocal microscopy, researchers
found a decrease in epithelial cell density and the number and
density of subbasal nerves in the dry eye patients compared to
controls (none had previous refractive surgery).13
Goblet cell density appears to be affected by LASIK. In a prospective study of 22 eyes, goblet cell density was decreased for at
least 1 month after LASIK, which may also play a causative role
in dry eye symptoms after refractive surgery.14
It is obviously a very complicated issue. The bottom line is,
what can we do to prevent these symptoms from developing? Are
there preoperative predictors of who will develop these symptoms? One study evaluated numerous preoperative parameters
including TBUT, Schirmer, and rose bengal staining before and
up to 9 months after LASIK. They found preoperative Schirmer
tests correlated with worse postoperative dry eye.15
Another study divided patients into preoperative dry eye,
probable dry eye, and no dry eye and evaluated postoperative
outcomes. While they found no differences in safety and efficacy
of the LASIK procedure, they did find more severe postoperative
dry eye, more corneal staining, and more severe dry eye symptoms in the group with preoperative dry eye.16 In 2001 in a study
in Ophthalmology, Dr. Steve Wilson concluded that LASIKinduced (presumed) neurotrophic epitheliopathy “tends to be
more common and severe in patients with pre-existing dry eye
disease.”17 Drs. Solomon, Donnenfeld, and Perry in their review
entitled “The effects of LASIK on the ocular surface” published
in the Ocular Surface Journal in 2004 note: “To prevent symptomatic postoperative dry eye, it is crucial to identify and treat
pre-existing dry eye before surgery.”18
Dry eye needs to be identified prior to considering corneal
refractive surgery. This is done during a complete ophthalmology examination, either performed or reviewed by the operating
surgeon. Components especially important in evaluating for dry
eye include a medical history (eg, rheumatoid arthritis, other
connective tissue disorders), medication history (eg, isotretinoin
[Accutane], beta-blockers, diuretics, others), and surgical history
(eg, blepharoplasty). The examination should include an external
examination for lid position/closure and rosacea and a slitlamp
examination for blepharitis, tear meniscus, TBUT, fluorescein
corneal staining. Lissamine green or rose bengal staining can be
extremely helpful to identify conjunctival damage from dry eye.
If a patient is determined to have dry eyes, the ocular surface
should be treated before considering corneal refractive surgery.
Treatment options include artificial tears, topical cyclosporine,
topical steroids, punctal plugs, and treating any blepharitis.
Preoperative cyclosporine has been shown to improve results of
LASIK.19,20
Ideally, corneal refractive surgery is delayed until the ocular
surface has “normalized.” Surgery can usually be safely performed if only mild residual dry eye signs remain. If significant
dry eye signs and symptoms persist, it is usually best not to proceed with surgery at that time.
With proper preoperative evaluation to identify patients at
higher risk of developing potentially severely symptomatic dry
eye-type symptoms after corneal refractive surgery, either these
patients can be treated prior to surgery to normalize their ocular
4
surface or they should not undergo surgery. You do not want to
turn a patient who is mildly unhappy with his or her glasses or
contact lenses into someone who hates him or herself (for having
paid money to feel they way they do) and you (for performing
the surgery).
References
1. Levinson BA, Rapuano CJ, Cohen EJ, Hammersmith KM, Ayres
BD, Laibson PR. Referrals to the Wills Eye Institute Cornea Service
after laser in situ keratomileusis: reasons for patient dissatisfaction.
J Cataract Refract Surg. 2008; 34:32-39.
2. Jabbur NS, Sakatani K, O’Brien TP. Survey of complications and
recommendations for management in dissatisfied patients seeking a
consultation after refractive surgery. J Cataract Refract Surg. 2004;
30:1867-1874.
3. Albietz JM, Lenton LM, McLennan SG. Chronic dry eye and
regression after laser in situ keratomileusis for myopia. J Cataract
Refract Surg. 2004; 30:675-684.
4. Shoja MR, Besharati MR. Dry eye after LASIK for myopia: incidence and risk factors. Eur J Ophthalmol. 2007; 17:1-6.
5. De Paiva CS, Chen Z, Koch DD, et al. The incidence and risk factors for developing dry eye after myopic LASIK. Am J Ophthalmol.
2006; 141:438-445.
6. Golas L, Manche EE. Dry eye after laser in situ keratomileusis with
femtosecond laser and mechanical keratome. J Cataract Refract
Surg. 2011; 37:1476-1480.
7. Salomão MQ, Ambrósio R Jr, Wilson SE. Dry eye associated with
laser in situ keratomileusis: Mechanical microkeratome versus femtosecond laser. J Cataract Refract Surg. 2009; 35:1756-1760.
8. Mian SI, Shtein RM, Nelson A, Musch DC. Effect of hinge position
on corneal sensation and dry eye after laser in situ keratomileusis
using a femtosecond laser. J Cataract Refract Surg. 2007; 33:11901194.
9. Mian SI, Li AY, Dutta S, Musch DC, Shtein RM. Dry eyes and
corneal sensation after laser in situ keratomileusis with femtosecond
laser flap creation: effect of hinge position, hinge angle, and flap
thickness. J Cataract Refract Surg. 2009; 35:2092-2098.
10. Battat L, Macri A, Dursun D, Pflugfelder SC. Effects of laser in situ
keratomileusis on tear production, clearance, and the ocular surface. Ophthalmology 2001; 108:1230-1235.
11. Lee JB, Ryu CH, Kim J, Kim EK, Kim HB. Comparison of tear
secretion and tear film instability after photorefractive keratectomy
and laser in situ keratomileusis. J Cataract Refract Surg. 2000;
26:1326-1331.
12. Tuisku IS, Lindbohm N, Wilson SE, Tervo TM. Dry eye and corneal sensitivity after high myopic LASIK. J Refract Surg. 2007;
23:338-342.
13. Benítez-Del-Castillo JM, Acosta MC, Wassfi MA, et al. Relation
between corneal innervation with confocal microscopy and corneal
sensitivity with noncontact esthesiometry in patients with dry eye.
Invest Ophthalmol Vis Sci. 2007; 48:173-181.
14. Rodriguez-Prats JL, Hamdi IM, Rodriguez AE, Galal A, Alio JL.
Effect of suction ring application during LASIK on goblet cell density. J Refract Surg. 2007; 23:559-562.
15. Konomi K, Chen LL, Tarko RS, et al. Preoperative characteristics
and a potential mechanism of chronic dry eye after LASIK. Invest
Ophthalmol Vis Sci. 2008; 49:168-174.
16. Toda I, Asano-Kato N, Hori-Komai Y, Tsubota K. Laser-assisted
in situ keratomileusis for patients with dry eye. Arch Ophthalmol.
2002; 120:1024-1028.
17. Wilson SE. Laser in situ keratomileusis-induced (presumed) neurotrophic epitheliopathy. Ophthalmology 2001; 108:1082-1087.
18. Solomon R, Donnenfeld ED, Perry HD. The effects of LASIK on the
ocular surface. Ocul Surf. 2004; 2:34-44.
19. Salib GM, McDonald MB, Smolek M. Safety and efficacy of cyclosporine 0.05% drops versus unpreserved artificial tears in dry-eye
patients having laser in situ keratomileusis. J Cataract Refract Surg.
2006; 32:772-778.
20. Ursea R, Purcell TL, Tan BU, et al. The effect of cyclosporine A
(Restasis) on recovery of visual acuity following LASIK. J Refract
Surg. 2008; 24:473-476.
5
Counterpoint: Selective Laser in Patients With
Dry Eye
I.Introduction
A. The most common complication of refractive surgery is dry eye. The risk of this complication can be
minimized with an intelligent, surgical, pharmacologic, and behavioral approach to refractive surgery.
In certain cases the correct decision is not to perform refractive surgery. At every step of the surgical
process, the surgeon should take the appropriate
steps to optimize the refractive outcome and minimize postoperative dry eye. Reducing the incidence
of post-refractive surgery dry eye is based on the following principles.
1. Identify patients at risk for dry eye
2. Maximize tear film stability preoperatively
3. Make a surgical plan to minimize dry eye
4. Postoperative therapeutic intervention
1. Refractive surgery patients are often contact
lens-intolerant with borderline dry eye prior to
surgery.
2. Damage to conjunctival goblet cells during
LASIK is induced by suction.
3. Changes in corneal curvature result in decreased
tear wetting secondary to lid movement.
4. Decreased sensation in dry eye patients reduces
feedback loop to produce tears.1
5. Medicamentosum from toxic antibiotics,
NSAIDS, and preservatives
6. Severing of corneal nerves by keratome and damage by photoablation.
1. Lissamine green/rose bengal conjunctival staining
2. Fluorescein corneal staining
3. Schirmer testing
4. Tear break-up time
5. Tear osmolarity/MMP-9 level
1. Antibiotic: Avoid aminoglycosides
2. Short-term use of nonsteroidals2
3. Minimize anesthetic use
Develop a surgical plan to reduce the incidence of dry
eye.
A. Several studies show a statistically significant
increase in dry eye with a superior hinged flap as
compared to a nasal hinged flap,7,9 although other
studies show no difference.8
B. Statistically significant increase in dry eye and
decrease in corneal sensation with a wider hinge flap
than a narrow hinge10
C. Smaller flaps are associated with less dry eye disease
than larger flaps.11
D. Deeper ablations are associated with increased dry
eye disease.9
E. Thin, planar flap
F. Reverse side cut
IV. How to Avoid LASIK P.O. Dry Eye/ Postop: Every
patient gets dry eye after LASIK—the question is
whether they know it or not.
A. Eyelid closure
B. Aggressive scheduled lubrication of ocular surface
1. Transiently/nonpreserved tears
2. Lubricating ointment at night, as needed
3. Punctal occlusion, as needed
A. Evaluate dry eye status
III. How to Avoid LASIK P.O. Dry Eye/Intraop
II. Optimizing Refractive Surgical Outcomes Preop
C. Avoid epithelial toxicity
B. Why do patients develop dry eye following corneal
refractive surgery?
4. Topical azithromycin
C. Prevent inflammation
1. Prednisolone acetate 1% q.i.d. for 5 days: gold
standard
2. Loteprednol to suppress chronic inflammation
3. Topical cyclosporine 0.05% b.i.d.12
V. Who to Avoid Refractive Surgery on Due to Dry Eye
Disease?
A. Patients who have corneal signs of tissue damage
due to dry eye disease
B. Evaluate the ocular surface/treat lid disease
1. Hot compresses/lid scrubs
2. High-dose omega-3 supplementation (Schwab,
OMIG. 1990)
1. No supravital conjunctival staining: Good candidate
2. Supravital conjunctival staining with no corneal
staining: Moderate candidate
3. Topical cyclosporine 0.05% b.i.d.
6
3. Supravital conjunctival staining with central
fluorescein corneal staining: Poor candidate
B. Patients who have symptoms of vision loss due to
dry eye disease
1. Stern ME, Beuerman RW, Fox RI. The pathology of dry eye: the
interaction between the ocular surface and the lacrimal glands. Cornea 1998; 17(6):584-589.
1. Dry eye symptoms and no effect on vision: Usually good candidate
2. Snyder, Bindi, Donnenfeld, Nichols. The effect of topical antibiotic
and NSAIDS on epithelial wound healing in a PRK animal model.
Presented at the Castroviejo Society meeting, 1997.
2. Dry eye symptoms and fluctuating vision: Moderate/poor candidate
3. Solomon, Donnenfeld, Perry, Kanellopoulos. Carboxymethylcellulose protection of the ocular surface in LASIK. ASCRS 2000.
3. Dry eye symptoms and decreased vision due to
ocular surface disease: Poor candidate
4. Lambiase A, Rama P, Aloe L, Barini S. Management of neurotrophic keratopathy. Curr Opin Ophthalmol. 1999; 10:270-276.
C. Dry eye disease and comorbidities: Often poor candidates
1. Neurotrophic corneas
a. Diabetics: check sensation
b. Herpes simplex/zoster
c. Structural lid disease
d. Fifth/seventh nerve palsies
D. Ocular surface disease resulting in:
1. Irregular topography
2. Hartman-Shack image
References
E. Patients who are poor candidates but who respond
well to dry eye disease therapy can become excellent
refractive surgery candidates.
1.Lubrication
2. Anti-inflammatory therapy
a.Cyclosporine
b.Corticosteroids
3. Punctal occlusion
4. Oral doxycline
5. Nutritional supplements
6. Treat lid disease
VI.Conclusion
With intelligent preoperative, intraoperative, and postoperative management, the incidence and severity of
refractive surgery-related dry eye can be significantly
decreased. Patients with decreased or fluctuating visual
acuity due to ocular surface disease, corneal staining,
and decreased corneal sensation that do not respond to
treatment are generally not good candidates for refractive surgery.
5. Kanellopoulos AJ, Pallikaris G, Donnenfeld ED. Comparison of
corneal sensation following PRK and LASIK. J Cataract Refract
Surg. 1997; 23:(1):34-38.
6. Chuck RS, Quiros PA, Perez AC, McDonnel PJ. Corneal sensation
after laser in situ keratomileusis. J Cataract Refract Surg. 2000;
26:(3):337-339.
7. Donnenfeld ED, Solomon, K, Perry, HD, Doshi SJ. The effect of
hinge position on corneal sensation and dry eye following LASIK.
Ophthalmology 2003; 110(5):1023-1029.
8. Vroman DT, Sandoval HP, Fernandez de Castro LE, Kasper TJ,
Holzer MP, Solomon KD. Effect of hinge location on corneal sensation and dry eye after laser in situ keratomileusis for myopia. J
Cataract Refract Surg. 2005; 31(10):1881-1887.
9. De Paiva CS, Chen Z, Koch DD, et al. The incidence and risk factors for developing dry eye after myopic LASIK. Am J Ophthalmol.
2006; 141(3):438-445.
10. Donnenfeld ED, Ehrenhaus M, Solomon R, Mazurek J, Rozell JC,
Perry HD. Effect of hinge width on corneal sensation and dry eye
after laser in situ keratomileusis. J Cataract Refract Surg. 2004;
30:790-797.
11. Rozell J, Donnenfeld E, Solomon R, Stein J, Ehrenhaus M, Perry H.
The effect of flap diameter and hinge position on corneal sensation
and dry eye following LASIK. American Society of Cataract and
Refractive Surgery Symposium on Cataract, IOL, and Refractive
Surgery, 2004.
12. Salib GM, McDonald MB, Smolek M. Safety and efficacy of cyclosporine 0.05% drops versus unpreserved artificial tears in dry-eye
patients having laser in situ keratomileusis. J Cataract Refract Surg.
2006; 32(5):772-778.
7
Point: Monovision Is the Way for Laser Vision
Correction
Dan Z Reinstein MD
The ideal solution for correcting presbyopia would be to restore
accommodation; however, no procedure up to now has been
proven to reverse presbyopia and restore the natural focusing
mechanism of the eye. While there is ongoing research on techniques to achieve this, clinical applications of these techniques
will probably not be available for another 10 to 20 years.1
Because of our inability to restore accommodation, current
treatments for presbyopia rely on splitting the refractive power
within the same eye for distance and near. The challenge for such
treatment options is to maintain optical quality—in particular
maintaining contrast sensitivity and not inducing night vision
disturbances. There are two approaches to achieving this using
corneal refractive surgery: monovision and multifocality.
Multifocal Ablations
Recently there has been a resurgence in corneal surgery to induce
multifocality. The aim of corneal multifocality is to provide both
distance vision and near vision correction within the optical
zone of each eye, therefore creating two retinal images in each
eye and relying on the brain to choose between multiple images.
In such procedures, either a central corneal area is steepened for
near vision, leaving the midperipheral cornea for far vision, or a
central area for distance vision is created with a midperipheral
corneal area for near vision. Although an overall improvement
in UCVA has been demonstrated both at distance and at near,
safety and quality of vision remain compromised. Recent studies have reported loss of 2 or more lines CDVA in up to 10% of
eyes,2,3 decrease in contrast sensitivity,3,4 and night vision disturbances.4,5
Recently, a new technique called Intracor has been suggested
where a series of concentric cylindrical rings are created intrastromally using a femtosecond laser to induce a central steepening to improve near vision. However, early studies have reported
a loss of at least 1 line CDVA in the majority of eyes and 2 or
more lines CDVA in 7%-8%,6,7 as well as a reduction in contrast
sensitivity and increased night vision disturbances.8 Also, longterm stability is unknown, refractive error cannot be corrected
simultaneously, and a retreatment is not currently possible.
Monovision
The well-established principles of contact lens monovision have
been used in laser refractive surgery; however, many of the limitations of contact lens monovision also affected laser refractive
surgery-induced monovision. These limitations include loss of
fusion due to the anisometropia between the two eyes,9 poor
intermediate vision,10 reduced binocular contrast sensitivity,11
and reduced stereoacuity.12 However, recent studies have demonstrated that many of these limitations could be avoided by
limiting the anisometropia to 1.25 D or 1.50 D.13 Interestingly,
monovision induced by refractive surgery can be tolerated by a
higher proportion of patients (92%) than monovision induced
by contact lenses (60%).14 It is unclear whether this might be due
to the relative ease of “giving up” with contact lens monovision,
compared to the relative increased time for neuroadaptation to
take place imposed by the requirement of surgical reversal.
Laser Blended Vision
Since 2003, a new procedure called “laser blended vision” has
been developed that combines elements of monovision with
increasing the depth of field within the cornea to improve the
fusional and stereo acuity limitations of monovision, as well as
maintain quality of vision.
To better understand the way laser blended vision works,
let’s consider presbyopia as a decrease in depth of field. It is
known that one way of increasing depth of field is to increase
the amount of corneal spherical aberration.15,16 Based on that
knowledge, the initial aim was to adjust the corneal depth of
field enough to provide clear vision at all distances from far
through intermediate to near. To achieve this, proprietary nonlinear increases in spherical aberration were introduced into the
ablation profiles, which were designed to adequately precompensate for the excess induction of spherical aberration observed in
myopic and hyperopic corrections. It is known that visual quality
and contrast sensitivity can be compromised by large amounts
of spherical aberration.17 Therefore, laser blended vision profiles
were designed to control (not eliminate) the induction of spherical aberration so that postoperative spherical aberration was
within a range that provides an increased depth of field, without
affecting contrast sensitivity and quality of vision. We discovered
that the depth of field of the cornea may be safely increased by
approximately 1.50 D for any starting refractive error. Given a
1.50-D depth of field, it would not be possible to get full distance
and full near vision monocularly; therefore, based on the timetested concept of monovision, the nondominant eye was set up
to be slightly myopic, so that the depth of field of the predominantly distance (dominant) eye was able to see at distance down
to intermediate, while the predominantly near (nondominant)
eye was able to see in the near range and up to intermediate.
In the intermediate region both eyes have similar acuity, thus
enabling binocular fusion. Monovision, or in this case, micromonovision, draws on the inherent cortical processes of neuronal
gating and blur-suppression—the ability for conscious attention
to be directed to the part of the visual field with the best image
quality.
The combination of controlled induced corneal aberrations
and pupil constriction (the miosis of accommodation) gives a significant increase in depth of field on the retinal image, albeit an
aberrated image. However, we must remember that the quality
of the perceived image is not the same as the quality of the retinal
image: intraretinal and cortical processing and edge detection
are neural processes that provide the final components contributing to the visual quality afforded by laser blended vision: the
actual retinal image, which is modified by spherical aberration,
is further enhanced by central processing to yield the perception
of clear and well-defined edges. Centration on the corneal vertex
is another critical component, so that the spherical aberration
induction is symmetrical around the visual axis rather than the
entrance pupil. During the procedure, both the flap and ablation
8
are centered on the corneal vertex, which closely approximates
the visual axis.
At 1 year after laser blended vision, binocular UDVA was
20/20 or better and UNVA was J2 or better in 95% of 136
myopic patients (≤ -8.50 D),18 77% of 111 hyperopic patients
(≤ +5.75 D),19 and 95% of 148 emmetropic patients (within
±0.88 D).20 The safety in terms of contrast sensitivity was the
same as for standard LASIK with the MEL80 with no eyes losing more than 1 line of CDVA. Mean postoperative mesopic
contrast sensitivity was either the same or slightly better than
preoperative at 3, 6, 12, and 18 cpd for all 3 populations, using
the CSV-1000.
Results of our stereo acuity studies21 (using a Rand-dot stereo
test) have found that while postoperative uncorrected stereoacuity was lower than preoperative near-corrected stereoacuity, a
functional level of stereo acuity was maintained postoperatively;
68% of patients had stereo acuity of 100 secs or better and 93%
had stereo acuity of 200 secs or better. The study also found that
near-correction restored preoperative near-corrected stereo acuity in the majority of patients; 5% of patients with 40-50 seconds
of stereo acuity preoperatively showed a 1 patch decrease in best
corrected stereo acuity, while 100% of patients initially 60 seconds or less showed no loss at all.
Summary
Advances in the treatment of presbyopia have brought a multitude of refractive corrective options to the patient, and techniques are constantly improving. While most procedures are
efficient in enhancing the ability of achieving distance and near
correction, many also come with significant side effects and
drawbacks. Monovision is a good option if the anisometropia is
limited to less than 1.50 D, and it carries the advantage of being
instantly reversible nonsurgically by spectacles or permanently
reversible by a simple LASIK enhancement procedure. Laser
blended vision offers a more sophisticated micro-monovision
option that renders continuous near, intermediate and distance
vision and avoids the drawbacks of multifocality. By applying
strict limits to the amount of spherical aberration induction,
the depth of field can be increased while minimizing the risk
of a reduction in quality of vision. Similarly, by using a micromonovision, binocular fusion and functional stereo acuity are
maintained, which greatly increases patient tolerance compared
with traditional monovision.
References
1. Blum M, Kunert K, Nolte S, et al. [Presbyopia treatment using a
femtosecond laser]. Ophthalmologe 2006; 103(12):1014-1019.
2. Jung SW, Kim MJ, Park SH, Joo CK. Multifocal corneal ablation
for hyperopic presbyopes. J Refract Surg. 2008; 24(9):903-910.
3. Jackson WB, Tuan KM, Mintsioulis G. Aspheric wavefront-guided
LASIK to treat hyperopic presbyopia: 12-month results with the
VISX platform. J Refract Surg. 2011; 27(7):519-529.
4. Pinelli R, Ortiz D, Simonetto A, Bacchi C, Sala E, Alio JL. Correction of presbyopia in hyperopia with a center-distance, paracentralnear technique using the Technolas 217z platform. J Refract Surg.
2008; 24(5):494-500.
5. Epstein RL, Gurgos MA. Presbyopia treatment by monocular
peripheral presbyLASIK. J Refract Surg. 2009; 25(6):516-523.
6. Holzer MP, Mannsfeld A, Ehmer A, Auffarth GU. Early outcomes
of INTRACOR femtosecond laser treatment for presbyopia. J
Refract Surg. 2009; 25(10):855-861.
7. Holzer MP, Knorz MC, Tomalla M, Neuhann TM, Auffarth GU.
Intrastromal femtosecond laser presbyopia correction: 1-year
results of a multicenter study. J Refract Surg. 2012; 28(3):182-188.
8. Fitting A, Menassa N, Auffarth GU, Holzer MP. [Effect of intrastromal correction of presbyopia with femtosecond laser (INTRACOR) on mesopic contrast sensitivity.]. Ophthalmologe 2012.
9. Durrie DS. The effect of different monovision contact lens powers on the visual function of emmetropic presbyopic patients (an
American Ophthalmological Society thesis). Trans Am Ophthalmol
Soc. 2006; 104):366-401.
10. Evans BJ. Monovision: a review. Ophthalmic Physiol Opt. 2007;
27(5):417-439.
11. Jain S, Arora I, Azar DT. Success of monovision in presbyopes:
review of the literature and potential applications to refractive surgery. Surv Ophthalmol. 1996; 40(6):491-499.
12. Fawcett SL, Herman WK, Alfieri CD, Castleberry KA, Parks MM,
Birch EE. Stereoacuity and foveal fusion in adults with long-standing surgical monovision. J AAPOS. 2001; 5(6):342-347.
13. Alarcon A, Anera RG, Villa C, Jimenez del Barco L, Gutierrez R.
Visual quality after monovision correction by laser in situ keratomileusis in presbyopic patients. J Cataract Refract Surg. 2011;
37(9):1629-1635.
14. Miranda D, Krueger RR. Monovision laser in situ keratomileusis
for pre-presbyopic and presbyopic patients. J Refract Surg. 2004;
20(4):325-328.
15. Cantu R, Rosales MA, Tepichin E, Curioca A, Montes V, RamirezZavaleta JG. Objective quality of vision in presbyopic and nonpresbyopic patients after pseudoaccommodative advanced surface
ablation. J Refract Surg. 2005; 21(5 suppl):S603-605.
16. Rocha KM, Vabre L, Chateau N, Krueger RR. Expanding depth of
focus by modifying higher-order aberrations induced by an adaptive
optics visual simulator. J Cataract Refract Surg. 2009; 35(11):18851892.
17. Artola A, Patel S, Schimchak P, Ayala MJ, Ruiz-Moreno JM, Alio
JL. Evidence for delayed presbyopia after photorefractive keratectomy for myopia. Ophthalmology 2006; 113(5):735-741 e731.
18. Reinstein DZ, Archer TJ, Gobbe M. LASIK for myopic astigmatism
and presbyopia using non-linear aspheric micro-monovision with
the Carl Zeiss Meditec MEL 80 Platform. J Refract Surg. 2011;
27(1):23-37.
19. Reinstein DZ, Couch DG, Archer TJ. LASIK for hyperopic astigmatism and presbyopia using micro-monovision with the Carl Zeiss
Meditec MEL80. J Refract Surg. 2009; 25(1):37-58.
20. Reinstein DZ, Carp GI, Archer TJ, Gobbe M. LASIK for the correction of presbyopia in emmetropic patients using aspheric ablation
profiles and a micro-monovision protocol with the Carl Zeiss Meditec MEL80 and VisuMax. J Refract Surg. 2012; 28(8):531-541.
21. Reinstein DZ, Archer TJ, Gobbe M. Safety, efficacy, contrast sensitivity and stereoacuity after corneal presbyopic LASIK in emmetropic patients. In: Seeing Is Believing: Vision 2010 (Meeting Guide
of the 2010 American Academy of Ophthalmology Subspecialty
Day). San Francisco: American Academy of Ophthalmology, 2010.
Counterpoint: No Monovision for Laser Vision
Correction
Notes
9
10
Point: Corneal Inlays for Corneal Presbyopia
Correction
Damien Gatinel MD
Introduction
Types of Corneal Inlays
Advances in refractive surgery over the past decade have brought
tremendous advances in the treatment of myopia, hyperopia, and
astigmatism. Our next great challenge is the surgical treatment of
presbyopia: as the world population ages, the demand for a reliable presbyopia correction solution will also increase. In 2010,
1.6 billion people were affected by presbyopia, and in 2020, the
number is estimated to grow to 2.1 billion.
In this presentation, I will present the general benefits of
corneal inlays, and share my experience with a small aperture
inlay (Kamra, Acufocus; Irvine, Calif., USA), which is currently
dominating the market of corneal inlays and may prove to be the
primary answer for presbyopia.
Kamra Corneal Inlay (Acufocus)
The Kamra small-aperture intracorneal inlay is designed to
increase depth of field in the implanted eye, based on the principle of small-aperture optics. The inlay restores near and intermediate visual acuity without a significant impact on the distance
vision.1-3 This 5-micron thick microperforated inlay has a 1.6mm central aperture and measures 3.8 mm in overall diameter.
The procedure takes less than 15 minutes and is performed in
the nondominant eye. Sutures are not required, and only topical
anesthesia in the form of eye drops is used.
Implantation can be combined with an excimer ablation to
simultaneously address presbyopia and ametropia. The inlay is
implanted monocularly either in a lamellar pocket or under a
200-micron femtosecond laser-created flap in the nondominant
eye.
Benefits of Corneal Inlays
• Using corneal inlays for vision correction, eye surgeons
may avoid complications sometimes associated with laserbased procedures such as LASIK and PRK because no corneal tissue is removed.
• These devices may have fewer risks than implantable
lenses because the surgery takes place within the cornea,
not inside the eye.
• The mechanism of action is well known, at least for small
aperture inlays, which provide enough depth of focus to
compensate for any presbyopia magnitude.
• The small aperture inlays increase depth of field, with a
minimal reduction of uncorrected distance vision in the
inlay eye compared with monovision, according to human
studies conducted thus far.
• Four- and five-year postop results show that the range of
vision achieved after surgery is maintained over the longer
term, which is not the case with other procedures that rely
upon refractive power or induced corneal multifocality.
These approaches are still subject to the progressive nature
of presbyopia.
• As the procedure is unilateral (nondominant eye), some
visual side effects such as night halos may be less perceptible in binocular vision conditions.
• Inlay surgery is adjustable (centration) and optically
reversible (removal of the inlay). The flap can be lifted and
the inlay easily separated from the underlying stroma to
allow for repositioning, removal or exchange.
• Inlays can be combined with other types of refractive
surgery, such as LASIK. Surgeons globally are evaluating
more advanced techniques to insert the inlay in postLASIK and pseudophakic patients.
• In the future, when patients develop cataracts requiring
removal, cataract surgery is possible with the inlays in the
cornea. To date, the combination of a small aperture inlay
with a monofocal lenses results in the same extended depth
of field as the inlay in an ametropic or emmetropic presbyope.
Raindrop Corneal Inlay (Revision Optics)
This 2-mm diameter inlay is made of medical-grade hydrogel
plastic similar to that used for soft contact lenses. According
to the company, it has optical characteristics that are almost
identical to the human cornea. The inlay is intended to improve
both near and intermediate vision by changing the curvature of
the cornea. The Raindrop corneal inlay is placed at about 150
microns within the cornea under a LASIK-style flap creating a
zone of additional vergence, much like a multifocal contact lens.
The inlay measures 2 mm in total diameter and is 25 microns
thick.
Flexivue Microlens (Presbia)
The Flexivue Microlens (Presbia Coöperation; Amsterdam,
Nederlands) is inserted into a femtosecond-laser created stromal
“pocket.” A specially developed instrument is used to insert the
microlens into the pocket. The lens is made of hydrophilic polymer. It is 3.2 mm in diameter and 15 microns thick at the edges.
It has a central hole measuring 1.6 mm in diameter and is available in +1.50 to +3.5 D refractive powers. The inlay is inserted
between 280 and 300 microns deep.
Important Points to Ensure Clinical Success With
Small Aperture Inlays
As with photoablative surgery, candidate selection is a crucial
step. In particular, the integrity of the cornea should be checked
by slitlamp examination and topography. Slitlamp examinations
should eliminate the presence of complicated dry eye manifestations. The intended visual benefits should be explained to the
patients, along with the information regarding possible side
effects such as dry eye and night halos.
Accurate refraction control is mandatory to achieve clinical
success: combined laser refractive surgery can be used to adjust
the refractive status of the implanted (and nonimplanted eye) if
necessary.
The flap or pocket dissection requires proper settings with
the femtosecond laser, to ensure the smoothest interface possible
prior to implanting the inlay.
Correct centration of a corneal inlay is important in order to
improve distance and near visual acuity and to avoid a reduction in quality of vision. The corneal intersection of the visual
axis is probably the best point on which to center the inlay. This
true position of the visual axis at the corneal plane is unknown,
but this point may be located close and temporally to the first
Purkinje image. The recommendation of the Kamra inlay manufacturer (AcuFocus) is to center the inlay over the corneal vertex.
However, in patients with a significant angle Kappa, the inlay
should be placed halfway between the corneal vertex and the
center of the entrance pupil. To achieve optimal centration, the
surgeon should try to identify the coaxial light reflex and its
position vs. the center of the entrance pupil. Additionally, use of
the AcuTarget Diagnostic Unit provides an objective measure of
the distance and direction of first Purkinje vs. the pupil center,
and postoperatively it correlates actual inlay placement vs. the
first Purkinje and the pupil center. Similar information may be
retrieved preoperatively from some Placido topographers; these
devices do not, however, have the capacity to identify and compare actual inlay placement vs. your target.
Postoperatively, the occurrence of ocular dryness is frequent
with flap techniques (simultaneous LASIK and inlay implantation). It should be monitored and treated aggressively.
11
Conclusion
Corneal inlays represent an effective method for presbyopia correction in carefully selected patients, and they represent a better
option than monovision for emmetropic and ametropic presbyope patients.
References
1. Waring GO IV. Correction of presbyopia with a small aperture corneal inlay. J Refract Surg. 2011; 27(11):842-845.
2. Seyeddain O, Hohensinn M, Riha W, et al. Small-aperture corneal
inlay for the correction of presbyopia: 3-year follow-up. J Cataract
Refract Surg. 2012; 38(1):35-45.
3. Dexl AK, Seyeddain O, Riha W, et al. Reading performance after
implantation of a small-aperture corneal inlay for the surgical correction of presbyopia: two-year follow-up. J Cataract Refract Surg.
2012; 37(3):525-531.
4. Mandell RB. Locating the corneal sighting center from videokeratography. J Refract Surg. 1995; 11(4):253-259.
5. Bouzoukis DI, Kymionis GD, Limnopoulou AN, et al. Femtosecond
laser-assisted corneal pocket creation using a mask for inlay implantation. J Refract Surg. 2011; 27(11):818-820.
6. Waring GO IV, Klyce SD. Corneal inlays for the treatment of presbyopia. Int Ophthalmol Clin. 2011; 51(2):51-62.
12
Counterpoint: Corneal Laser for Presbyopia
Correction
Gustavo Tamayo MD, Claudia Castell MD, Pilar Vargas MD
Presbyopia is a very common refractive defect with many surgeries developed in order to correct it, besides glasses or contact
lenses. However, many of them have disappeared and only a few
have survived.
Today, we only have two real surgical options: IOLs that are
either accommodative or bifocal or multifocal lenses. A second
option is surgery on the cornea of three types: excimer laser ablation in the form of LASIK or surface ablation (named generally
as presbyLASIK), femtosecond intrastromal corneal surgery, and
corneal inlays.
In the last American Academy of Ophthalmology survey by
Duffey, it was very clear that in presbyopia precataract patients,
IOLs are not very well accepted, and in fact their use may be
decreasing in the United States, with only around a 4% preference. Instead, any form of excimer laser surgery is accepted,
being the majority use of monovision. LASIK surgery is a very
well-known surgery even for the general ophthalmologist, well
described and with a very low rate of complications. Therefore,
presbyLASIK is an excellent option for the correction of presbyopia.
Excimer laser on the cornea and implantation of a corneal
inlay creates at the end a topography defined multifocal cornea.
A multifocal cornea faces several problems: (1) decreased contrast visual acuity that returns to normal levels between 3 to 6
months. (2) It also produces visual symptoms similar to the ones
produced by multifocal lenses: haloes, glare, and night vision
problems. However as a big difference from the lenses, this sur-
gery is completely reversible as a CustomVue treatment, erasing
the multifocality.
Presbyopia excimer laser surgery is based on the creation of
corneal aberration mostly of the type of spherical aberrations,
which once present in the cornea, increase the depth of focus,
allowing independence from the use of glasses for near vision.
We utilize the so-called peripheral corneal ablation, which is an
excimer program that creates distance vision in the center of the
cornea and near vision through the periphery. This type of ablation creates a central positive spherical aberration (Z40) and a
peripheral negative spherical aberration (Z60). This combination
increases depth of focus. A couple of examples of this type will
be presented (see Figures 1 and 2).
Results
121 eyes from 66 patients have been followed up for close to 3
years. Mean age is 51 years with a range between 41 to 67 years.
Preoperative sphere is 0.180 ± 2.2 D (-5.0 to +5.0 D). Preoperative cylinder is -0.736 ± 0.97 (-6.5 to 0.0 D). 57.9% of the
patients were hyperopic, 31.4% were myopic, and 10.7% were
emmetropic. 86.8% were treated in a LASIK format either with
femtosecond or with microkeratome. Cases had 9.9% retreatment rate at 1 to 3 months (enhancement surgery).
Ninety-four percent of the eyes were 20/30 or better uncorrected for distance, and 95% of the eyes were 20/25 or better
for near. 100% of the eyes reached 20/25 or better BCVA for
Figure 1.
13
Figure 2.
distance and near, and no loss of lines of BCVA were detected.
When analyzed by refractive defect, myopes behave better with
this type of surgery when compared to hyperopes for distance
and near.
In general, 92% of the patients do not wear glasses at any
condition, and all of them will recommend the surgery to a
friend. However, 3.2% of the patients do not drive at night due
to visual symptoms.
With these results, presbyLASIK offers another option for
the so called “young” presbyopic patient (between 43 and 56
years of age), since it is not an invasive surgery and certainly
does not carry all the disastrous complications of intraocular
surgery. Even more, LASIK is a widespread and well-known surgery, easily performed and easily managed in the postoperative
period. Most ophthalmologists around the world are prepared
and trained to do it, and therefore fewer complications can be
expected. It is also reversible with a wavefront surgery—a big
difference from IOLs. Its main disadvantage is the fact that
the correction is temporary (around 5 years), but it is still an
excellent option for the patient and the doctor not willing to go
inside the eye for a problem solved easily with glasses. One great
advantage of excimer surgery on the cornea is the fact that it is
applied in combination with the correction of another refractive defect such as astigmatism, which is better solved with an
excimer than with toric IOLs.
Corneal Inlays
Corneal inlays are the other corneal surgery for presbyopia that
constitute an excellent option for the patient not willing to wear
glasses for such a refractive defect. The inlays are refractive discs
inserted at different depths inside the stroma, with different
mechanisms of action dependent of the type of inlay. Currently
we have three options for inlays, but the one used by the presenter is the so called Flexivue Microlens from Presbia Corp.
All inlays are inserted only in the nondominant eye, producing a sort of controlled monovision—of course without all the
big difference between both eyes. However, patients must be
tested for tolerance to small monovision, such as +1.25 in one
eye and emmetropia in the other eye.
Surgical technique is briefly described, being a very easy and
simple procedure with the help of the femtosecond laser that
makes the tunnel to insert the inlay. A special emphasis on centration on the Purkinje image is made, emphasizing this step as
one of the most important in the surgical procedure.
Inlays are only for emmetropes at the present, although several studies are under way to see their efficacy in other refractive defects once they are treated with excimer laser. Results are
excellent, provided the patient is properly selected. All patients
are 20/20 binocular, but the eye of the inlay is mean 20/50 the
first month, reaching 20/30 at 6 months and stable after 1 year
of follow-up. For near, all eyes are 20/30 or better, vision that
is reached very quickly during the first month and stable for the
next year.
The inlays also produce visual symptoms, just as intraocular
multifocal lenses and presbyLASIK. The main disadvantage is
poor tolerance to the difference between both eyes. The great
advantage of the corneal inlay is total reversibility, as it can be
removed and the eye returns to the normal situation and/or the
possibility to exchange it over time, according to the changes in
vision during the aging process.
14
PRK and LASEK Techniques
Parag A Majmudar MD
Synopsis of Video
This video presentation will review current surface ablation techniques. Topics of discussion will include epithelial removal techniques such as manual debridement, alcohol-assisted epithelial
removal, and excimer-laser assisted removal. Current thinking
on photorefractive keratectomy vs. LASEK vs. epi-LASIK will be
presented. Optimal use of mitomycin C will also be reviewed.
Selected Readings
1. Kieval JZ. Techniques in surface ablation: a comparison of visual
outcomes and complications. Int Ophthalmol Clin. 2011; 51(2):110.
2. Taneri S, Weisberg M, Azar DT. Surface ablation techniques. J
3. Reynolds A, Moore JE, Naroo SA, Moore CB, Shah S. Excimer
laser surface ablation: a review. Clin Experiment Ophthalmol.
2010; 38(2):168-182.
4. Santhiago MR, Netto MV, Wilson SE. Mitomycin C: biological effects and use in refractive surgery [review]. Cornea 2012;
31(3):311-321.
5. Chen SH, Feng YF, Stojanovic A, Wang QM. Meta-analysis of
clinical outcomes comparing surface ablation for correction of myopia with and without 0.02% mitomycin C. J Refract Surg. 2011;
27(7):530-541.
15
Pupil Tracking, Centration, and Iris Registration (IR)
Louis Probst MD
I. Advanced technology has improved outcomes of
LASIK over the last decade.
A. Pupil tracking
B. Wavefront correction
C. Iris registration (IR)
D. Femtosecond lasers
A. Average UCDA post-LASIK 20/20 visual acuity rate
has improved from 75% to 93%.
B. Average UCDA post-LASIK 20/15 visual acuity rate
has improved from 12% to 35%.
C. Enhancement rates have dropped from 10% to
< 2%.
D. Currently with the most advanced technology,
> 90% and > 50% of eyes achieved a UCDA of
20/16 and 20/12 or better, respectively.
III. Importance of Tracker Centration
A. Center of the pupil is determined by pupil tracker.
B. IR adjustments based on tracked center.
C. Offset tracker = Offset IR adjustments
A. Schedule upgrade during next regular service call.
B. Tracker monitor upgrade kit part number 00303911 at a list price of $283.52
C. If laser has a printer that attaches through a USB kit,
USB hub, printer and driver: Star S4IR Part Number
0030-6097, list price $499.43.
A. A round pupil on tracking monitor indicates wellcentered tracker.
B. Opaque bubble layer (OBL) will block some of the
pupil and distort image.
C. Large pupils can have reflection of tracking lights
that distort image.
D. Bubbles in the anterior chamber after femtosecond
flaps will displace tracker.
VI. Solutions to Incomplete Pupil Tracking
A. Reset tracker.
B. Wipe away OBL and recheck tracker monitor.
D. If bubble in anterior chamber, turn off tracker and
manually fixate eye or wait 4-5 hours for bubbles to
resolve.
VII. Iris Registration
A. Identifies unique matching points on the iris
B. Matches the wavefront image to the image captured
under the laser
C. Patient identify and eye are verified
D. Cyclorotation and centroid shift are identified and
corrected
VIII. IR Capture: Easiest to Most Challenging
A. Virgin eye
B. PRK eyes
C. LASIK enhancement
D.Microkeratome
E.IntraLase
IX. Misaligned Limbal Rings Wavefront Capture
A. Brown eyes
B. Pigment around limbal
C. Pigment on scleral
D. Small corneas
E. Poor exposure
F. Can still have “green box”
V. Effective tracking requires that the infrared tracking
lights have clear access to pupil.
IV. Retro-fit Tracker Monitor
C. Increase illumination to reduce peripheral reflection
and recheck monitor.
II. Uncorrected visual outcomes after LASIK have
improved over the last decade.
X. Misaligned Limbal Rings – IR
A. Peripheral OBL
B. Indentation mark of suction ring
C. Brown eyes
D. Peripheral scars
E. Asymmetrical limbus
XI. Solutions to Align Limbal Rings
A. Personally check all wavefront captures: Even with
“green box.”
B. Review/repeat questionable alignment.
C. Personally check all IR captures: Even if “verified”
D. Consider performing IR prior to the femtosecond
laser: Achieves almost 100% capture rate
16
LASIK Enhancement Techniques
I.Concepts
C. Transition zone: 0.5 mm
A. Integral aspect of refractive surgery, 5%-30% rate
D. Spherical adjustment: 0.65 D
B. Increased enhancement rates with:
E. Standard PRK: 6.0 mm
1. Conservative primary surgery
F. 125 MMC if indicated. Apply in all enhancements.
2. Higher postop visual acuity goal (20/20 goal will
need enhancement more often than 20/40 goal)
G. Frozen/cold BSS irrigation
H. Medications + BCL
II. Methods of Retreatment
A. Surface ablation (PRK)
B. Relift original flap
C. New side cut in the original LASIK flap (investigational)
D. Recutting with microkeratome/femto (not recommended)
VIII.Complications
A. No intraoperative or postoperative complications
B. No haze or scarring postoperatively
C. No infections
IX.Summary
A. Flap lift enhancement works well in the first 12-36
months.
B. Epithelial ingrowth is frequent in flap lift enhancement after 36 months.
C. PRK, especially transepithelial PRK, is an attractive
option for LASIK enhancement.
D. Nomogram adjustment is required with significant
higher aberration to reduce consecutive hyperopia
(Lindstrom adjustment in sphere: HOA -0.20).
III. Major Life Complication: Epithelial Ingrowth
A. Isolated nests/sheets of cells
B. Decreased UCVA and/or BCVA
C. Induced astigmatism on refraction
D. Irregular astigmatism on topography
IV. Epithelial Ingrowth After LASIK
Microkeratome at primary LASIK
V. Incidence of Epithelial Ingrowth
Caster A, et al. J Cataract Refract Surg. 2009.
A.
N = 3866
B. Primary cases (n = 360): 0
C. Flap lift enhancement (n = 646): 2.3%
D. Flap lift enhancement less than 3 years, postop:
1.07%
E. Flap lift enhancement more than 3 years, postop:
7.7%
VI. PRK as an Enhancement Option for Residual Refractive Error
For low residual refractive errors transepithelial PRK is
an attractive option.
VII. Transepithelial PRK
A. 65 micron PTK
B. PTK diameter: 6.5 mm
References
1. Lin RT, Maloney RK. Flap complications associated with lamellar
refractive surgery. Am J Ophthalmol. 1999; 127:129-136.
2. Anderson, NJ, Hardten DR. Fibrin glue for the prevention of epithelial ingrowth after laser in situ keratomileusis. J Cataract Refract
Surg. 2003; 29:1424-1429.
3. Caster AL, Friess DW, Schwendeman FJ. Incidence of epithelial
ingrowth in primary and retreatment laser in situ keratomileusis. J
Cataract Refract Surg. 2010; 36 (1):97-101.
4. Yoo SH. Strategies for re-treatment after prior refractive surgery.
In: Refractive Surgery 2011: Precision in Vision—The Latest in
Cornea- and Lens-Based Refractive Surgery (Meeting Guide of the
2011 American Academy of Ophthalmology Refractive Surgery
Subspecialty Day). San Francisco: American Academy of Ophthalmology; 2011.
5. Davis EA, Hardten DR, Lindstrom M, Samuelson TW, Lindstrom
RL. LASIK enhancements: a comparison of lifting to recutting the
flap. Ophthalmology 2002; 109(12): 2308-2313.
17
Suction Loss
Pravin K Vaddavalli MD
Introduction
Conclusion
Although femtosecond lasers seem to have become the technique
of choice, the microkeratome is still widely used for LASIK flap
creation. Down sides of the microkeratome include greater variability of flap thickness and intraoperative flap complications,
with a higher incidence of epithelial ingrowth.1 Reported complication rates with the mechanical microkeratome vary from
1.26% to 0.24%, depending on the platform used.2-4
Achievement of adequate suction prior to the microkeratome
pass is one of the prerequisites for successfully creating a LASIK
flap. The most common reported complications of creating a
LASIK flap with the mechanical microkeratome include flap buttonholes (0.041%-0.13%), partial or incomplete flaps (0.049%0.099%), thin or incomplete flaps (0.091%-0.087%), free caps
(0.012%-0.086%), and epithelial defects (0.049%).2-4 Though
the inability to achieve suction is reported in a very small number
of patients (0.034%), the etiology of a number of other complications like partial flaps, irregular flaps, thin flaps, and incomplete flaps is believed to be due to poor suction during surgery.5,6
Suction loss with the microkeratome or microkeratome jam can
occur for a number of reasons.7,8 It is imperative to remember
that once a partial pass is made, a partial flap is created and a
repeat microkeratome pass has the potential to macerate the
previously made partial flap. The best approach in these cases
may be to reposition the partial flap and either perform a recut
with a femtosecond laser a few months later or perform surface
ablation.9
Synopsis
4. Carrillo C, Chayet AS, Dougherty PJ, et al. Incidence of complications during flap creation in LASIK using the Nidek
MK-2000 microkeratome in 26,600 cases. J Refract Surg. 2005;
21:S655-S657.
We present a case of suction loss during microkeratome flap creation for LASIK that resulted in an unexpected complication.
A 25-year-old male patient presented to us with a bandaged
right eye following a history of attempted LASIK elsewhere. His
preoperative refractive error was +5.50 D. When we contacted
his primary surgeon, he revealed that he had a microkeratome
suction loss during the procedure, and when suction was reapplied and a recut performed, a semi free cap was produced.
During surgery for repositioning the flap, the free cap was
found in the lower fornix of the patient and as 6 hours had transpired since the initial surgery, the bed had epithelial ingrowth.
The bed showed a semicircular stromal defect with the crescentric margin on the distal margin and a linear edge across the center of the cornea. When the free cap was examined, it appeared
to be dissected into two lamellae with an attachment at the distal
end.
The bed was cleaned meticulously and all the epithelium was
debrided off the bed and the free cap. After orienting the flap on
the bed, it seemed poorly adherent to the bed. The free cap was
sutured with 10 nylon sutures and a bandage contact lens was
applied.
Postoperatively the flap was well apposed with no epithelial
ingrowth. Sutures were removed 2 weeks postop, and a corneal topography done at that visit showed that the cornea had
regained a near normal anterior curvature.
References
1. Lee JK, Nkyekyer EW, Chuck RS. Microkeratome complications.
Curr Opin Ophthalmol. 2009, 20:260-263.
2. Jacobs JM, Taravella MJ. Incidence of intraoperative flap complications in laser in situ keratomileusis. J Cataract Refract Surg. 2002;
28:23-28.
3. Nakano K, Nakano E, Oliveira M, et al. Intraoperative microkeratome complications in 47,094 laser in situ keratomileusis surgeries.
J Refract Surg. 2004; 20:S723-S726.
5. Choudhri SA, Feigenbaum SK, Pepose JS. Factors predictive of
LASIK flap thickness with the Hansatome zero compression microkeratome. J Refract Surg. 2005; 21(3):253-259.
6. Ma XL, Xu JG, Liu HQ. Effect of microkeratome suction duration
on corneal flap thickness and diameter in pigs. Int J Ophthalmol.
2010; 3(2):125-127.
7. Kim YH, Choi JS, Chun HJ, Joo CK. Effect of resection velocity
and suction ring on corneal flap formation in laser in situ keratomileusis. J Cataract Refract Surg. 1999; 25(11):1448-1455.
8. Balachandran C, Aslanides IM. Break in microkeratome oscillating pin during LASIK flap creation. Cont Lens Anterior Eye. 2010;
33(3):144-146.
9. Rubinfeld RS, Hardten DR, Donnenfeld ED, et al. To lift or recut:
changing trends in LASIK enhancement. J Cataract Refract Surg.
2003; 29(12):2306-2317.
18
LASIK Striae Management
Ronald R Krueger MD
Notes
Femtosecond LASIK Complications
Sub-Bowman keratomileusis (SBK) refers to a flap thickness less
than 110 µm. To investigate the safety of SBK, we retrospectively
reviewed the records of 9360 eyes that had SBK with flaps created by femtosecond lasers from 2004 to March 2012. In this
study cohort, 6182 eyes (66%) had an intended flap thickness of
90 µm and 3178 eyes (34%) had an intended flap thickness of
100 µm. The type of flap-related complications and their occurrences were analyzed. The overall flap-related complication rate
was 0.74% (69 of 9360).
The most common type of complications was diffuse lamellar keratitis (28%), followed by flap tear (20%) and vertical
gas breakthrough (VGB, 13%). Thirteen of 69 eyes (19%) had
complications, lost 1 line of best distance corrected visual acuity
(BDCVA). The BDCVA changed from 20/20 to 20/25 in 2 eyes
and from 20/15 to 20/20 in 11 eyes.
In the past 12 months, 1381 SBK procedures were performed.
Ninety-nine percent of eyes had an intended flap thickness of
90 µm. The complication rate was only 0.29% (4 cases, 1 VGB,
2 flap fold and 1 incomplete flap). No loss in VA was reported.
SBK with femtosecond laser is safe and the complication rate
is low. Intraoperative management of complications such as
VGB and flap tear will be discussed.
19
20
Keynote Lecture
Corneal Presbyopia Surgery
Sonia H Yoo MD
To satisfy the increasing patient demand for spectacle independency, development of significant improvements in refractive
surgery have been made over the past decade. Corneal presbyopia surgery cannot restore effective accommodation but is an
alternative option for the treatment of presbyopia by increasing
depth of field. Presbyopia can be compensated for surgically by
performing lens extraction and implanting a multifocal or an
accommodating IOL, but the topic of this presentation will focus
on corneal presbyopic surgery. Depending on the presbyopic
patient’s ametropia, several different corneal procedures can be
performed.
The strategy of monovision correction for presbyopia allows
a patient to have the nondominant eye corrected for near vision
and the dominant eye corrected for distance vision, reducing
dependency on spectacles and contact lenses for most daily activities. Monovision has been used successfully for years by contact
lens wearers and more recently has been applied to refractive
surgery candidates. Monovision is often suggested for myopic
patients.
Corneal inlays implanted monocularly in the cornea of
emmetropic presbyopic patients improve near and intermediate
vision. They increase the depth of field, mimicking the pinhole
effect, without changing refractive status. Currently 3 corneal
inlays are being developed: the AcuFocus/Bausch + Lomb ACI
7000, the InVue intracorneal microlens (Biovision; Brugge,
Switzerland), and the PresbyLens (ReVision Optics; Lake Forest,
Calif., USA). They are biocompatible and have a central hole
pattern facilitating the nutrient flow within the cornea. A femtosecond laser can be used to create either a standard LASIK flap
or a small-incision corneal pocket, and the surgeon places the
inlay inside the cornea.
The Intracor intrastromal procedure using femtosecond laser
is another corneal stromal procedure for presbyopia correction.
Five central intrastromal rings are created by a femtosecond laser
in the center of cornea. The treatment steepens the center of cornea to increase the patient’s depth of field.
PresbyLASIK is usually performed in hyperopic presbyopic
eyes. Two approaches have been developed: Central presbyLASIK creates a central area for near vision and a peripheral area
for distance vision. Peripheral presbyLASIK creates a central area
for distance vision and a peripheral area for near vision. In these
two procedures, the ablation profile induces a multifocal corneal
surface, which allows patients to improve their near, intermediate, and distance vision.
Finally, conductive keratoplasty is another approach to treat
low and mild hyperopia. In this procedure, low heat energy from
radio frequency waves is applied through a probe to reshape
cornea.
21
Riboflavin Penetration Into the Cornea
Jesper Hjortdal MD
Introduction
Corneal crosslinking (CXL) has become widely used to treat
early stages of keratoconus and iatrogenic corneal ectasia.1 Riboflavin (or vitamin B2) has a molecular weight of 376.36 g/mol
and is a hydrophilic molecule. As the corneal epithelium has tight
junctions between individual cells, riboflavin cannot penetrate
the intact corneal epithelium.
The standard CXL treatment therefore includes mechanical
debridement of the corneal epithelium within a 9-mm diameter
zone and subsequent application of 0.1% riboflavin every 3
minutes for 30 minutes before initiating UV-A irradiation (370
nm, 3 mW/cm2) for 30 minutes in combination with continuous
riboflavin dripping.2
During UV-A irradiation, stromal collagen and/or glycosaminoglycans are photochemically crosslinked via the natural lysyl
oxidase pathway.3 Riboflavin acts as a photosensitizer for production of oxygen free radicals, which are necessary for the CXL
process, but it also absorbs the UV-A irradiation and prevents
damage to deeper structures such as the corneal endothelium,
lens, and retina.
The efficacy and safety of a CXL treatment depends upon
proper imbibition of the corneal stroma with riboflavin.
The CXL procedure is generally considered to be safe, but
the epithelial debridement associated with the standard CXL
treatment is followed by a few days of discomfort and pain and
slow visual recovery. In order to reduce these side effects, various
attempts to perform the CXL procedure with the epithelium on
have been suggested.
The aim of the present syllabus and talk is to give an overview
of riboflavin penetration into the debrided cornea and to summarize how chemical modifications to riboflavin solutions and
surgical modifications of the technique may be used to perform
CXL without complete debridement of the corneal epithelium.
Riboflavin Penetration Into the Debrided Cornea
Riboflavin penetrates readily into the anterior portion of the
debrided cornea. Basic animal studies by Spörl et al (2000)4 indicate, however, that a reasonably high riboflavin concentration
is only obtained in the anterior 200-300 microns of the corneal
stroma, and similar findings have been obtained with fluorescence microscopic measurements of intrastromal riboflavin
concentrations.5 Increasing the riboflavin concentration from
0.1% to 0.2% results in a higher intrastromal riboflavin concentration,5 but biomechanical tests suggest that similar stiffening
of the corneal tissue is obtained with riboflavin concentrations
ranging from 0.015% to 0.15%.4
Riboflavin Penetration Into the Undebrided Cornea
Researchers have investigated whether a superficial scratching
of the epithelial surface, manually or by excimer laser ablation,
rather than complete debridement of the corneal epithelium,
would be sufficient to ensure penetration of riboflavin to the
corneal stroma. Even if the tight junctions between the superfi-
cial epithelial cells are removed with an excimer laser, the basal
epithelial cell layers act as a barrier to riboflavin penetration.6
Similarly, superficial scraping with a thin needle, creating a grid
pattern, was found insufficient to allow riboflavin penetration to
the stroma.7
A number of chemical substances have a toxic effect on the
corneal epithelium. Thus, benzalkonium chloride (BAC), tetracaine, pilocarpine, ethylenediaminetetraacetic acid (EDTA),
gentamycin, oxybuprocaine, and trometamol have been used to
enhance riboflavin penetration through the intact epithelium.
Experimental studies in vitro have shown that 0.01%-0.02%
BAC in a hypo-osmolar (0.44% NaCl) solution can increase
the uptake of riboflavin to approximately one-third of the
concentration obtained in debrided corneas.8,9 With 0.005%
BAC and riboflavin 0.1% in 20% dextran T-500, Wollensak et
al (2009)10 found that corneal crosslinking without epithelial
debridement reduced the biomechanical effect to approximately
one-fifth compared with standard crosslinking. Trometamol and
EDTA can be used to enhance riboflavin uptake in corneas with
superficial scrapings, but the uptake is considerably less than in
corneas with removed epithelium.7 In vitro, tetracaine was found
inefficient to permit penetration of riboflavin into the corneal
stroma.11
Conclusions
The penetration of riboflavin into the corneal stroma is dependent upon the integrity of the corneal epithelium. Complete
debridement of the epithelium most effectively ensures proper
imbibition of the corneal stroma with riboflavin. Some of the
published chemical modifications of riboflavin solutions for
performing transepithelial CXL are promising, but they should
not be used routinely until safety and efficacy has been studied in
detail.
References
1. Wollensak G. Crosslinking treatment of progressive keratoconus:
new hope. Curr Opin Ophthalmol. 2006; 17:356-360.
2. Wollensak G, Spoerl E, Seiler T. Riboflavin/ultraviolet-A-induced
collagen crosslinking for the treatment of keratoconus. Am J Ophthalmol. 2003; 135:620-627.
3. Andley U. Photooxidative stress. In: Albert DM, Jakobiec FA, eds.
Principles and Practice of Ophthalmology. Philadelphia: WB Saunders; 1992:575-590.
4. Sporl E, Schreiber J, Hellmund K, et al. Studies on the stabilization
of the cornea in rabbits. Ophthalmologe 2000; 97:203-206.
5. Søndergaard AP, Hjortdal J, Breitenbach T, Ivarsen A. Corneal distribution of riboflavin prior to collagen cross-linking. Curr Eye Res.
2010; 35:116-121.
6. Bakke EF, Stojanovic A, Chen X, Drolsum L. Penetration of riboflavin and postoperative pain in corneal collagen crosslinking: excimer
laser superficial versus mechanical full-thickness epithelial removal.
22
7. Alhamad TA, O’Brart DP, O’Brart NA, Meek KM. Evaluation of
transepithelial stromal riboflavin absorption with enhanced riboflavin solution using spectrophotometry. J Cataract Refract Surg.
2012; 38:884-889.
8. Kissner A, Spoerl E, Jung R, Spekl K, Pillunat L, Raiskup F. Pharmacological modification of the epithelial permeability by benzalkonium chloride in UVA/riboflavin corneal collagen cross-linking.
Curr Eye Res. 2010; 35:715-721.
9. Raiskup F, Pinelli R, Spoerl E. Riboflavin osmolar modification for
transepithelial corneal cross-linking. Curr Eye Res. 2012; 37:234238.
10. Wollensak G, Iomdina E. Biomechanical and histological changes
after corneal crosslinking with and without epithelial debridement.
11. Hayes S, O’Bart DP, Lamdin LS, et al. Effect of complete epithelial
debridement before riboflavin-ultraviolet-A corneal collagen crosslinking therapy. J Cataract Refract Surg. 2008; 34:657-661.
23
Crosslinking: Epithelium On or Off?
Leopoldo Spadea MD
Corneal collagen crosslinking (CXL) with riboflavin and ultraviolet A (UVA) is a technique to strengthen corneal tissue using
riboflavin as a photosensitizer and UVA to increase the formation of intra- and interfibrillar covalent bonds by photosensitized
oxidation. Today, CXL is limited to eyes with a corneal thickness of at least 400 mm due to concerns about the cytotoxic
effect on the endothelium, crystalline lens, and other intraocular
tissues.1 This threshold has limited its performance in some eyes
with advanced stages of corneal ectasia. The downside of the
current pachymetric limitation is that patients with keratoconus
or keratectasia often have corneas that are thinner than the 400
mm threshold.1 Transepithelial CXL,2 CXL with customized
pachymetric-guided epithelial debridement preserving the epithelium in thinner corneal regions,3 and the concept of iatrogenic
corneal swelling before CXL application4 have been developed
as alternative techniques for thin corneas. The theoretical basis
for transepithelial CXL presents two major challenges: corneal
epithelium plays a role as barrier to UVA penetration, due to a
significantly high absorption coefficient in the ultraviolet (UV)
spectra, and the difficulty of penetration of a hydrophilic macromolecule such as riboflavin (molecular weight 376.37 g/mol)
through the corneal epithelium.5
After obtaining institutional review board approval and
informed consent, we performed transepithelial CXL with modified riboflavin and UVA irradiation in 14 patients affected by
progressive keratoconus, each with thinnest pachymetry values
ranging from 356 to 386 mm and not treatable using standard
techniques with de-epithelialization. The treatment was performed, under sterile conditions, as follows: riboflavin 0.1%
solution in 15% dextran T500 containing sodium ethylenediaminetetraacetic acid (EDTA) 0.01%, and tris[hydroxymethyl]
aminomethane (tromethamol) (Ricrolin TE, Sooft; Montegiorgio, Italy) were instilled every 10 minutes for 2 hours. Then topical anesthesia with oxybuprocaine 0.4% eyedrops (preserved
with p-hydroxybenzoate) (Benoxinato Cloridrato, Alfa Intes;
Naples, Italy) were instilled every 5 minutes for 15 minutes. One
drop of pilocarpine 1% was then instilled to constrict the pupil
and reduce UVA irradiation to the lens and the retina. An eyelid speculum was inserted and riboflavin was instilled over the
cornea every 3 minutes for 15 minutes. Ultraviolet A irradiation
was delivered by a CBM Vega X-Linker device (CBM, X-linker,
CSO; Florence, Italy). The device was calibrated to 3.0 mW/cm2
of surface irradiance (5.4 J/cm2 surface dose) using a UV light
meter at the specified working distance. UVA irradiation was
applied to the central 9 mm of the cornea for 30 minutes, while
the riboflavin solution was instilled every 5 minutes. The aiming
beam was focused on the central cornea, while the patient fixated
on a pulsating green light. At the end of the procedure, the eye
was rinsed with balanced salt solution and a therapeutic bandage
soft contact lens was applied. An antibiotic regimen of ofloxacin
drops and flurbiprofen drops were administered 4 times a day
for 1 week. Topical corticosteroid (butyrate clobetasone 0.1%)
drops then were administered for 1 month and then subsequently
tapered and titrated. In one patient affected by an advanced stage
of keratoconus and cataract, after providing informed consent,
a triple procedure was planned (penetrating keratoplasty, open
sky extracapsular cataract extraction, and IOL implantation)
6 months after transepithelial CXL, allowing us to study the
immunohistochemical findings.
Epithelial healing was complete in all patients after 1 day of
use of a bandage soft contact lens. No side effects or damage to
the limbal region were observed during the follow-up period. All
patients slightly improved in uncorrected and spectacle-corrected
visual acuities by 0 to 1 lines of visual acuity and a small reduction of the spherical equivalent manifest refraction. Computerized videokeratography showed a small reduction in the ectasia
(K max values reduced by 1.5 to 3.0 D) and keratometric astigmatism (reduced 0.2 to 2.0 D) in all patients, while noncontact
endothelial specular microscopy analysis demonstrated no
significant corneal endothelial cell changes either in quantity or
quality. The patients described an improved and comfortable
quality of vision and described themselves as being satisfied with
the outcome. In our experience, the application of transepithelial
CXL using riboflavin with substances added to enhance epithelial permeability did not alter the epithelial and endothelial function, showing a normal expression of Connexin-43, and keratocytes appeared to be regularly arranged and normally distributed
throughout the stroma, as shown by CD-34 immunoreactivity,
even in these very thin keratoconic corneas.
References
1. Spoerl E, Mrochen M, Sliney D, et al. Safety of UVA riboflavin
cross-linking of the cornea. Cornea 2007; 26:385-389.
2. Wollensak G, Iomdina E. Biomechanical and histological changes
after corneal crosslinking with and without epithelial debridement.
3. Kymionis GD, Diakonis VF, Coskunseven E, et al. Customized
pachymetric guided epithelial debridement for corneal collagen
cross linking. BMC Ophthalmol. 2009; 9:10-14.
4. Hafezi F, Mrochen M, Iseli HP, Seiler T. Collagen crosslinking with
ultraviolet-A and hypoosmolar riboflavin solution in thin corneas. J
Cataract Refract Surg. 2009; 35:621-624.
5. Samaras K, O’Brart DP, Doutch J, et al. Effect of epithelial retention and removal on riboflavin absorption in porcine corneas. J
Refract Surg. 2009; 25:771-775.
24
Long-term Results and Complications in Keratoconus
John Males MBCB FRANZCO
Introduction
Keratoconus is an asymmetric corneal ectatic disorder resulting
in irregular astigmatism and deterioration of vision.1 Keratoconus usually begins at puberty and progresses in approximately
20% of patients to such an extent that either lamellar or fullthickness corneal transplantation becomes necessary to preserve
vision, and it therefore has a significant impact on quality of life.2
One of the recent advances in refractive surgery has been the
introduction of corneal collagen crosslinking using the photosensitizer riboflavin and ultraviolet light for treating progressive
keratoconus.
Several clinical reports including a recent randomized controlled trial by Hersh et al3 have suggested that crosslinking
is effective in stabilizing keratoconus and is associated with a
reduction in corneal steepening and a variable improvement
in visual acuity; however, few studies have a mean maximum
follow-up of over 12 months.4,5 Collagen crosslinking was introduced for the first time in Australia in 2006 as a treatment option
for progressive keratoconus, and in this presentation, I would
like to discuss the long-term visual and refractive outcome of
these cases.
To summarize, treated eyes demonstrated a significant flattening at mean 14 months follow- up and a continued decrease
after 12 months and 24 months follow-up. This is in good agreement with the other long-term studies by Caporossi et al4 and
Raiskup-Wolf et al.5 In comparison, there was a significant worsening of Kmax in the untreated fellow eye eyes; this is similar to
the findings of Witting- Silva et al.6
The findings of this study emphasize the fact that when left
untreated, keratoconus can progress and result in corneal steepening and deterioration of visual acuity, and that corneal collagen crosslinking is an effective modality for treating these cases
by reducing the corneal curvature and improving visual acuity.
Further long-term follow-up of CXL is warranted given the typically young age at treatment.
Results/Conclusions
This long-term prospective study included 51 eyes of 35 patients
with progressive early to moderate keratoconus (corneal thickness of at least 400 µm) who underwent crosslinking and were
compared with a control group of 25 fellow eyes with keratoconus that did not undergo the procedure. The mean age of
patients was 24.25 ± 8.08 years (range: 15-39 years); there were
34 males and 17 females. The mean follow-up period was 14.38
± 9.36 months (range: 6-48 months).
Analysis of the treated group demonstrated a significant
reduction of maximum keratometry (Kmax) by 0.96 ± 2.33 D
(P = .005) and a significant improvement in BCVA from 0.21 to
0.16 logMAR (P = .04). In contrast, in the fellow control group,
Kmax increased significantly by 0.43 ± 0.85 D (P = .05) and
there was a worsening of BCVA from 0.14 to 0.19 logMAR (P =
.2). No significant differences were noted regarding cylindrical
power, spherical equivalent, or corneal thickness in either group.
Figure 1. Comparison of difference in Kmax between treated and fellow
control eyes during follow-up.
Figure 2. Corneal topography showing a reduction in Kmax in a treated
eye after crosslinking.
Figure 3. Corneal topography showing an increase in Kmax in a control
eye on follow-up.
The possible complications of crosslinking include pain
and sensitivity to bright light in the first few days, transient or
persistent corneal stromal haze,7 progression of disease,8 and
rarely infectious keratitis including bacterial,9 Acanthamoeba,10
and viral herpetic infections.11 In this study , the failure rate of
crosslinking (percentage of eyes with continued progression) was
23.5%, 12/51 eyes progressed by mean 1.05 ± 1.04 D, as compared to 37/51 eyes (72.5%) that flattened by mean 1.52 ± 1.50
D and 2/51 eyes (4%) that remained the same.
To conclude, corneal collagen crosslinking appears to be a
promising procedure for treating progressive keratoconus with
a few reported side effects. Nevertheless, the possibility of a secondary infection after the procedure exists because the patient
is subjected to epithelial debridement, use of topical corticosteroids, and application of a soft contact lens and hence needs to
be appropriately counselled.
25
Case Report: Complication
References
A case of polymicrobial keratitis following crosslinking is
discussed. A 32-year-old patient with collagen crosslinking
performed elsewhere developed bacterial keratitis caused by
Streptococcus salivarius, Streptococcus oralis, and coagulasenegative Staphylococcus sp. He presented on Day 3 after the procedure with a severe keratitis with an 8-mm epithelial defect and
360-degree ring infiltrate and admitted to removing his bandage
contact lens and cleaning it in his mouth before reapplying it in
his eye. He was treated with fortified topical antibiotics drops
and recovered a BCVA of 20/50.
1. Rabinowitz YS. Keratoconus. Surv Ophthalmol. 1998; 42:297-319.
2. The Australian Corneal Graft Registry. 1990 to 1992 report. Aust
N Z J Ophthalmol. 1993; 21:1-48.
3. Hersh PS, Greenstein SA, Fry KL, et al. Corneal collagen crosslinking for keratoconus and corneal ectasia: one-year results. J Cataract
Refract Surg. 2011; 37:149-160.
4. Caporossi A, Mazzotta C, Baiocchi S, Caparossi T. Long-term
results of riboflavin ultraviolet a corneal collagen cross-linking for
keratoconus in Italy: The Siena Eye Cross Study. Am J Ophthalmol.
2010;149:585-593.
5. Raiskup-Wolf F, Hoyer A, Spoerl E, Pillunat LE. Collagen crosslinking with riboflavin and ultraviolet-A light in keratoconus: longterm results. J Cataract Refract Surg. 2008; 34:796-801.
6. Wittig-Silva C, Whiting M, Lamoureux E, et al. A randomized
controlled trial of corneal collagen cross-linking in progressive keratoconus: preliminary results. J Refract Surg. 2008; 24:S720-725.
7. Mazzotta C, Balestrazzi A, Baiocchi S, Traversi C, Caporossi A.
Stromal haze after combined riboflavin-UVA corneal collagen
cross-linking in keratoconus: in vivo confocal microscopic evaluation. Clin Experiment Ophthalmol. 2007; 35:580-582.
8. Koller T, Mrochen M, Seiler T. Complication and failure rates after
corneal crosslinking. J Cataract Refract Surg. 2009; 35(8):13581362.
Figure 4.
9. Zamora KV, Males JJ. Polymicrobial keratitis after a collagen crosslinking procedure with postoperative use of a contact lens: a case
report. Cornea 2009; 28:474-476.
10. Rama P, Di Matteo F, Matuska S, Paganoni G, Spinelli A. Acanthamoeba keratitis with perforation after corneal crosslinking and
bandage contact lens use. J Cataract Refract Surg. 2009; 35:788791.
11. Kymionis GD, Portaliou DM, Bouzoukis DI, et al. Herpetic keratitis with iritis after corneal crosslinking with riboflavin and ultraviolet A for keratoconus. J Cataract Refract Surg. 2007; 33:19821984.
Figure 4.
26
Long-term Results and Complications in Post-LASIK
Ectasia
Theo Seiler MD PhD
N o t es
Combined Crosslinking and Laser Ablation
Reprinted with permission from SLACK, Inc., ©2012.
• Kanellopoulos AJ. The Athens Protocol: PRK and CXL.
In: Buratto L, ed. PRK: Past, Present and Future. 2012:
85-88.
• Kanellopoulos AJ. Management of Corneal ectasia after
LASIK with combined, same-day topography-guided
partial transepithelial PRKand collagen cross-linking: the
Athens protocol. J Refract Surg. 2011; 27(5):323-331.
Also reprinted with permission from Dove Press, ©2012: Kanellopoulos AJ. The management of cornea blindness from severe
corneal scarring, with the Athens Protocol (transepithelial topography-guided PRK therapeutic remodeling, combined with sameday, collegan cross-linking). Clin Ophthalmol. 2012; 6:87-90.
27
28
Chapter 8
THE ATHENS PROTOCOL:
PRK AND CXL
Anastasios John Kanellopoulos, MD
A
second procedure for visu
visual rehabilitation may been
b
comp
minorr complications
in a small number of eyes
sometimes be needed
ed afte
after
er cornea collagen within
w
s
our large series.
Out of the 400 eyes studied,
cross-linking (CXL)
L) for tre
treatment
atment of progres- just two required
required repeat
rep
CXL, and none needed to
sive keratoconus or post-LASIK
t-LASIK ectasia. Following have a cornea
corn
nea transplant.
transplan
XL for
or ectasia
tasi ca
many years of employingg CXL
cases,, w
we
introduced the “Athens Protocol”: same-day topography-guided partial PRK
K and CXL.
Copyrighted
material.
Our findings support
rt
that simultaneous
topogra- Not for distribution.
phy-guided partial PRK with cornea collagen crosslinking (CXL) offers a safe and effective approach for
normalizing the cornea and enhancing visual function
Although the efficacy of CXL for stabilizing kerain eyes with ectatic conditions. The core importance of tectasia is well-established and the procedure also
combining CXL in this technique is to address highly causes some corneal flattening, significant residual
irregular astigmatism in the management of eyes with astigmatism limiting contact lens wear may be a
keratoconus and post-LASIK ectasia.
persistent problem for some patients. This situation
Our theoretical and clinical evidence supports the creates an indication to perform topography-guided
use of this “Athens protocol” where CXL and topogra- PRK.
phy-guided surface ablation are performed in the same
While surface ablation in a keratoconic eye may
session rather than sequentially over time.
sound unorthodox, the goal of our treatment using
It is our experience that surface ablation using the the topography-guided software is to normalize the
topography-guided excimer laser platform (Allegretto, corneal surface and improve best-corrected acuity.
Alcon/WaveLight) effectively and predictably normal- This is a therapeutic procedure, not a refractive one.
izes the corneal surface and improves functional vision, In fact, some eyes turn out more myopic postoperaand we believe there is a synergistic effect when this tively, but have significant regularity and best specprocedure is performed simultaneously with CXL.
tacle-corrected visual acuity. We use surface ablation
Safety with our combination approach has been to remove no more than 50 µm of stroma and typifavorable as well. Although postoperative haze and cally treat only 2 D to 2.5 D of astigmatism and up to
delayed epithelial healing have occurred, these have 1 D of myopia.
Meeting Visual
Meetin
R
h bilit
Rehabilitation
Needs
85
Buratto L.
PRK: Present, Past, and Future. (pp. 85-88)
© 2012 SLACK Incorporated
86
Chapter 8
29
Figure 8-1. The basic
steps of the Athens
Protocol: Top left,
The PTK treatment is
planned on the Alcon/
WaveLight platform.
Top right, Following
the PTK, areas of
Bowman’s have been
ablated by the PTK,
confirming that the epithelium over the cone
is thinner. Bottom left,
The treatment plans of
the topography-guided
partial PRK that is the
core concept of this
protocol. Bottom right,
MC application prior to
the riboflavin and CXL.
The protocol begins with
hCopyrighted
a 6.5-mm phototherashows
thefor
areadistribution.
of cross-linkin
cross-linking is much broader and
material.
Not
peutic keratectomy (PTK) to remove 50 µm of epi- denser in the latter eye.
thelium. Then, the topography-guided partial PRK
We additionally introduced the theory that the
is performed followed by mitomycin C application PRK-treated eye represents a better biomechanical
(0.02% for 20 seconds) and the CXL procedure. The model for performing the CXL procedure. In theory,
excimer laser ablation resembles part of a hyperopic an eye with a more regularized surface from CXL as
treatment. It is performed using a 5.5-mm effec- opposed to an irregular untreated cornea would be
tive optical zone and targets steepening of the area better able to handle ongoing strain from IOP and
adjacent to the cone in an attempt to regularize the eye rubbing over the cone peak and would more likely
corneal surface (Figure 8-1).
remain more stable.
We believe our rationale for performing the two
We believe redistribution of corneal strain by
procedures simultaneously with the ablation first has remodeling the cornea with surface ablation is a sigseveral advantages. We have reported data showing nificant factor in the synergistic effect achieved when
that the corneal epithelium and Bowman’s membrane performing the two procedures together. The simulcan act as barriers to UVA light penetration into the taneous procedure also avoids removing cross-linked
stroma. As these tissues are removed with the PTK/ cornea, which occurs when performing CXL first folPRK procedure, it seems intuitive that the efficacy of lowed by the laser treatment.
the CXL procedure would be increased. This concept
Results from a comparison of two large, consecuis supported by clinical findings outlined below.
tive series of eyes treated at the same session or with
For example, in a patient who had CXL alone in one CXL first followed 1 year later by a topographyeye and the Athens protocol in the other, inspection guided surface ablation showed statistically signifiof OCT maps for hyper-reflectivity, which we recently cant differences in a number of outcome parameters
described as a sign of the extent of cross-linking, favoring the same-day procedure. The study, which
30
The Athens Protocol: PRK and CXL
87
Figure 8-3. Cornea OCT of the same eye 7 months postop
Figure 8-2. A clinical picture of the right eye of a 27-yearold man with advanced KCN. Preop BSCVA was 20/50
with -2.5 -5 @80. The patient underwent the Athens
Protocol and is now UCVA 20/30 and BSCVA 20/20 with
-1 -1.5 @85. The slit-lamp photo shows the corneal clarity
and the ground-glass appearance typical of CXL.
Copyrighted material.
Figure 8-4. A comparison of preoperative and 7 months
postoperative of Pentacam images showing the significant normalization of the cone and keratometric flattening and better symmetry.
has been published,1 included 127 eyes in the sequential group and 198 eyes treated with the Athens protocol (Figure 8-2).
For the eyes in the sequential group, mean logMAR
uncorrected visual acuity (UCVA) improved from 0.9
to 0.49, mean logMAR best spectacle-corrected visual
acuity improved from 0.41 to 0.16, mean K decreased
by 2.75 D and mean MRSE by 2.5 D, and the mean
haze score was 1.2. For the eyes in the simultaneous
group, there was a significantly greater improvement
Athens Protocol. One can appreciate the anterior cornea
hyper-reflectivity consistent with CXL and the demarcation line at about 300 µm depth depicting (as we have
introduced and published) the depth of effective CXL.
Those clinicians familiar with findings following CXL
alone may appreciate the enhanced depth and diameter
of the CXL effect noted on OCT supporting the advantage
on the eye with the Athens Protocol.
logMAR
UCVA (from 0.96 to 0.3) and mean
in mean lo
gMAR UC
llogMAR BSCVA
SCVA (from 0.39 to 0.11) as well as a sign
nificantly greater m
mean reduction in MRSE (-3.2 D)
keratometry
and kerato
metry (-3.5 D) (Figures 8-3 and 8-4). The
mean haze score in the simultaneous group was 0.5,
wass ssignificantly
aand
d tthatt w
ni ant lower than in the controls.
Central corneal thickness decreased by 70 µm after
there was no significant change
both procedures, and th
the
Not
for distribution.
in endothelial
cell count in either group. These findings demonstrate that performing the two procedures
together offers advantages of less PRK-associated
scarring and better riboflavin and UVA penetration
to achieve a wider and deeper CXL effect with greater
corneal flattening.
Reference
1. Kanellopoulos AJ. Comparison of sequential vs same-day
simultaneous collagen cross-linking and topographyguided PRK for treatment of keratoconus. J Refract Surg.
2009;25(9):S812-S818.
Bibliography
Kanellopoulos AJ. Cross-linking plus topography-guided PRK
for post-LASIK Ectasia Management. In: Garg A, Rosen E,
eds. Instant Clinical Diagnosis in Ophthalmology Refractive
Surgery. New Delhi, India: Jaypee Brothers; 2008:258-269.
Kanellopoulos AJ. Cross-linking plus topography-guided PRK
for post-LASIK ectasia management. In: Garg A, ed.
31
Management of Corneal Ectasia After LASIK
With Combined, Same-day, Topographyguided Partial Transepithelial PRK and
Collagen Cross-linking: The Athens Protocol
Anastasios John Kanellopoulos, MD; Perry S. Binder, MS, MD
ABSTRACT
PURPOSE: To evaluate a series of patients with corneal
ectasia after LASIK that underwent the Athens Protocol:
combined topography-guided photorefractive keratectomy (PRK) to reduce or eliminate induced myopia and
astigmatism followed by sequential, same-day ultraviolet
A (UVA) corneal collagen cross-linking (CXL).
METHODS: Thirty-two consecutive corneal ectasia cases underwent transepithelial PRK (WaveLight
ALLEGRETTO) immediately followed by CXL (3 mW/cm2)
for 30 minutes using 0.1% topical riboflavin sodium
phosphate. Uncorrected distance visual acuity (UDVA),
corrected distance visual acuity (CDVA), manifest refraction spherical equivalent, keratometry, central ultrasonic
pachymetry, corneal tomography (Oculus Pentacam),
and endothelial cell counts were analyzed. Mean followup was 27 months (range: 6 to 59 months).
RESULTS: Twenty-seven of 32 eyes had an improvement
in UDVA and CDVA of 20/45 or better (2.25 logMAR)
at last follow-up. Four eyes showed some topographic
improvement but no improvement in CDVA. One of the
treated eyes required a subsequent penetrating keratoplasty. Corneal haze grade 2 was present in 2 eyes.
CONCLUSIONS: Combined, same-day, topography-guided
PRK and CXL appeared to offer tomographic stability, even
after long-term follow-up. Only 2 of 32 eyes had corneal
ectasia progression after the intervention. Seventeen of
32 eyes appeared to have improvement in UDVA and
CDVA with follow-up 1.5 years. This technique may offer an alternative in the management of iatrogenic corneal ectasia. [J Refract Surg. 2011;27(5):323-331.]
doi:10.3928/1081597X-20101105-01
P
rogressive, asymmetrical corneal steepening associated with an increase in myopic and astigmatic refractive errors, combined with midperipheral and/or
peripheral corneal thinning, represents a constellation of
findings in ectatic corneal disorders, such as keratoconus
and pellucid marginal degeneration. Asymmetry in presentation and unpredictability of progression associated with a
myriad of abnormal topographic findings describe these entities. Similar findings following LASIK have been described
as corneal ectasia.1-3 Analysis of different series of eyes developing corneal ectasia after LASIK has suggested that certain preoperative and/or operative features may be associated
with this adverse outcome of LASIK or photorefractive keratectomy (PRK).4 The fact that corneal ectasia can occur in the
absence of these features, or that it does not occur despite the
presence of these features,5 has confounded our understanding of this entity. Nevertheless, corneal ectasia after LASIK is
a visually disabling complication with an ultimate surgical
treatment of penetrating keratoplasty when spectacles or contact lenses can no longer provide patients with the quality of
vision to permit activities of daily living.
Over the past 10 years, the use of topical riboflavin combined with ultraviolet A (UVA) irradiation to increase collagen cross-linking (CXL) has demonstrated the potential for
retarding or eliminating the progression of keratoconus and
corneal ectasia after LASIK. The application of CXL in corneal ectasia after LASIK has been reported previously.6 Once
From LaserVision.gr Institute, Athens, Greece (Kanellopoulos); New York
University Medical College (Kanellopoulos) and Manhattan Eye, Ear and
Throat Hospital (Kanellopoulos), New York, New York; and Gavin Herbert
Eye Institute Department of Ophthalmology, University of California, Irvine,
California (Binder).
The authors have no financial interest in the materials presented herein.
Presented as a paper at the American Society of Cataract and Refractive
Surgery annual meeting; April 9-14, 2010; Boston, Massachusetts.
Correspondence: A. John Kanellopoulos, MD, LaserVision.gr Institute, 17
Tsocha St, Athens, 11521 Greece. Tel: 30 210 7472777; Fax: 30 210 7472789;
E-mail: [email protected]
Received: April 20, 2010; Accepted: October 13, 2010
Posted online: November 5, 2010
Management of Corneal Ectasia After LASIK/Kanellopoulos & Binder
32
the progression has stabilized, it is possible to treat the
surface of the eye with customized PRK to normalize
the corneal surface by reducing irregular astigmatism
and potentially reducing the refractive error as well
as providing improved visual outcomes in addition to
stabilizing the disease process.7,8 We have subsequently
introduced the combined, same-day use of these two
intervention modalities in the management of keratoconus.9-11
We present a series of patients with corneal ectasia
after LASIK who have undergone combined, same-day,
topography-guided PRK and subsequent UVA collagen CXL to achieve stabilization of corneal ectasia and
enhance visual rehabilitation.
PATIENTS AND METHODS
PATIENT SELECTION
Patients entered into this study were seen by one
of the authors (A.J.K.) in his private practice, either
through individual patient referral, referral from other
eye care practitioners, or were his own patients. Once a
diagnosis of corneal ectasia after LASIK was confirmed
(see below), patients were presented with the options
of contact lens fitting, intracorneal ring segment implantation, or, in advanced cases, penetrating keratoplasty. If these modalities did not serve the needs of
the patient, he/she was then presented with the option
of undergoing topography-guided PRK and UVA collagen CXL as a possible technique to prolong or prevent
the need for penetrating keratoplasty. Patients provided
verbal and written consent prior to undergoing the
combined topography-guided PRK/CXL procedure.
A diagnosis of corneal ectasia was made when
patients developed progressive corneal steepening
associated with an increasing myopic and/or astigmatic refractive error 2 or more months after LASIK
surgery. These findings were combined with increasing inferior corneal steepening and thinning based on
videokeratography and ultrasound pachymetry. Preoperative LASIK clinical data and topography were requested from the referring physician or primary LASIK
surgeon for analysis. Progression of the myopic refractive error with or without progression of the manifest
astigmatism, decreasing uncorrected distance visual
acuity (UDVA), loss of corrected distance visual acuity (CDVA), progressive inferior corneal steepening on
topography, and/or decreasing inferior corneal thickness were findings in all cases.
CLINICAL EXAMINATION
Each patient underwent manifest refraction as well
as measurement of UDVA and CDVA, which was re324
corded in a 20-foot lane using high-contrast Snellen
visual acuity testing. Cycloplegic refractions were
performed using 1% tropicamide solution (Alcon
Laboratories Inc, Ft Worth, Texas). Slit-lamp microscopy confirmed the presence of a LASIK flap. Keratometry readings were obtained by videokeratography
(Topolyzer; WaveLight AG, Erlangen, Germany) and/or
manual keratometry (model 71-21-35; Bausch & Lomb,
Rochester, New York). Pachymetry was performed using at least one of the following devices/instruments:
Pentacam (Oculus Optikgeräte GmbH, Wetzlar, Germany),
Orbscan II (Bausch & Lomb), or EchoScan US-1800
(NIDEK Co Ltd, Gamagori, Japan). Specular microscopy
was performed using the Konan specular microscope
(Konan Medical, Boston, Massachusetts). Topography
was performed using the Orbscan II or Pentacam.
SURGICAL TECHNIQUE—THE ATHENS PROTOCOL
We have reported this technique in the management
of keratoconus.9-11
Step 1. The (Partial, Spherically Corrected)
Topography-guided Transepithelial PRK Technique.
We devised this technique based on the proprietary
WaveLight customized platform. As noted above, we
previously described the use of the topography-guided
platform with this device to normalize irregular corneas as well as corneal ectasia.
This customized excimer laser treatment is guided
by topographic images and is different from wavefrontguided treatments. It received CE mark for clinical use
in the European Union in 2003; however, it has yet to
receive US Food and Drug Administration approval.
This proprietary software utilizes topographic data
from the linked topography device (Topolyzer). By
default, it permits the consideration of eight topographies (of predetermined threshold accuracy), averages
the data and enables the surgeon to adjust the desired
postoperative cornea asphericity (chosen as zero in all
cases), provides the option of including tilt correction
(no tilt was chosen in all cases), as well as the adjustment of sphere, cylinder, axis, and treatment zone (optical zone of 5.5 mm was chosen in all cases). The image of
the planned surgery is generated by the laser software.
We used topography-guided PRK to normalize the
cornea by reducing irregular astigmatism while treating part of the refractive error. To remove the minimum
possible tissue, we decreased the effective optical zone
diameter to 5.5 mm in all cases (compared to our usual
treatment diameter of at least 6.5 mm in routine PRK
and LASIK). We also planned ~70% treatment of cylinder and sphere (up to 70%) so as not to exceed 50 µm
in planned stromal removal. We chose the value of
50 µm as the maximum ablation depth effected, based
Copyright © SLACK Incorporated
33
on our experience of treating irregular corneas with
this platform.7-10
Following the placement of an aspirating lid speculum (Rumex, St Petersburg, Florida), a 6.5-mm, 50-µm
phototherapeutic keratectomy (PTK) was performed
to remove the corneal epithelium. Partial topographyguided PRK laser treatment was applied. A cellulose
sponge soaked in mitomycin C (MMC) 0.02% solution
was applied over the ablated tissue for 20 seconds followed by irrigation with 10 mL of chilled balanced salt
solution.
Step 2. Collagen CXL Procedure. For the next 10
minutes, the proprietary 0.1% riboflavin sodium phosphate ophthalmic solution (Priavision, Menlo Park,
California) was applied topically every 2 minutes. The
solution appeared to “soak” into the corneal stroma
rapidly, as it was centrally devoid of Bowman layer.
Following the initial riboflavin administration, 4 diodes emitting UVA light of mean 370-nm wavelength
(range: 365 to 375 nm) and 3 mW/cm2 radiance at 2.5 cm
were projected onto the surface of the cornea for 30
minutes (Keracure prototype device, Priavision). The
Keracure device, which has a built-in beeper, alerts
clinicians every 2 minutes during the 30-minute treatment to install the riboflavin solution in a timely fashion. A bandage contact lens was placed on the cornea
at the completion of the combined procedures.
Postoperatively, topical ofloxacin (Ocuflox 0.3%;
Allergan Inc, Irvine, California) was used four times a
day for the first 10 days and prednisolone acetate 1%
(Pred Forte, Allergan Inc) was used four times a day
for 60 days. Protection from all natural light with sunglasses was encouraged, with administration of oral
1000 mg vitamin C daily for 60 days postoperative.
The bandage contact lens was removed at or around
day 5 following complete re-epithelialization.
EVALUATION
The following evaluations were completed before and
after both treatments: age, sex, UDVA, CDVA, refraction, keratometry, tomography, pachymetry, endothelial cell count, corneal haze on a scale of 0 to 4 (0=clear
cornea, 1=mild haze, 2=moderate haze, 3=severe haze,
and 4=reticular haze [obstructing iris anatomy]), and
corneal ectasia stability as defined by stability in mean
keratometry and tomography.
CASE REPORTS
CASE 1
A 39-year-old man had undergone LASIK in May
2004 at another institution. At that time, according to
patient history, UDVA was counting fingers in both
Journal of Refractive Surgery • Vol. 27, No. 5, 2011
eyes. Manifest refraction was 6.50 0.50 020
(20/20) in the right eye and 6.00 0.50 165 (20/20)
in the left eye. Preoperative keratometry and corneal
thickness readings were not available. No surgical data
were available. The patient achieved UDVA of 20/20
in each eye, and reportedly plano refraction in both. In
October 2005, he complained of progressively decreasing vision in both eyes. At that time, UDVA was 20/50
in the right eye and 20/40 in the left eye and he was
told that “astigmatism was developing.”
The patient presented in March 2006, 26 months
after LASIK, with a manifest refraction of 2.25 1.75
090 (20/20) in the right eye and 1.25 0.75 010
(20/20) in the left eye. Uncorrected distance visual acuity was 20/40 in the right eye and 20/30 in the left eye.
Keratometry was 38.75@90/35.62@180 in the right eye
and 40.65@05/39.55@95 in the left eye. Central corneal
thickness (measured with Pentacam and ultrasound)
was 495 µm in the right eye and 505 µm in the left eye,
respectively. A diagnosis of bilateral corneal ectasia
was made.
Because of the decrease in UDVA and the presence
of corneal ectasia, the patient was informed of the risks,
benefits, and alternatives of the combined topographyguided PRK/CXL technique. This procedure was performed on both eyes in January 2007, 32 months after
LASIK. Based on the clinical manifest refraction of
right (2.25 1.75 90 [20/20]) and left (1.25 0.50
005 [20/20]) eyes, the attempted correction was reduced to 1.75 1.50 90 and 0.75 0.50 005
for the right and left eyes, respectively. (The goal in
the treatment was modified to anticipate the possible
long-term flattening effect that CXL may have on these
corneas.)
In February 2010, 37 months after topography-guided
PRK/CXL, UDVA improved to 20/40 in the right eye and
20/20 in the left eye with a manifest refraction of 0.75
in the left eye. Keratometry was 37.50@85/36.62@175
in the right eye and 37.75@79/37.87@169 in the left
eye. Ultrasound pachymetry was 440 µm and 414 µm
in the right and left eyes, respectively. Figure 1 demonstrates the pre- and postoperative topographies of the
right eye as well as the difference map after treatment
with the Athens Protocol.
CASE 2
A 33-year-old woman reportedly had a manifest refraction of 4.00 2.50 90 (20/20) in the right eye
and 1.50 2.00 100 (20/20) in the left eye. No other
preoperative data were available. The patient had a
history of eye rubbing.
Sometime in 2002, the patient underwent bilateral
325
Management
ofIII:
Corneal
Ectasia
After LASIK/Kanellopoulos & Binder
34
Section
Corneal
Crosslinking
Figure 1. Case 1. Clinical course of the right eye. Topography on the left shows marked central inferior corneal steepening consistent with corneal
ectasia. The center image shows the final topography 2 years after initial LASIK, which is flatter and normalized. The image on the right demonstrates
the comparison between preoperative and postoperative.
LASIK (the exact date is unknown and the surgical
data were unavailable). Initially, the patient recovered excellent UDVA, but in December 2005, approximately 3 years postoperatively, she presented with
slowly decreasing vision in both eyes. At that time,
UDVA was 20/800 in each eye. Manifest refraction
was 10.50 6.00 105 (20/40) in the right eye and
7.75 2.50 110 (20/30) in the left eye. Central corneal thickness measured by ultrasound was 395 µm
in the right eye and 410 µm in the left eye. Keratometry was 52.87@103/46.12@13 in the right eye and
47.12@111/45.00@021 in the left eye. Corneal topography revealed bilateral corneal ectasia after LASIK,
which was more pronounced in the right eye.
On December 19, 2005, 3 years after LASIK, the
patient underwent topography-guided PRK/CXL in the
right eye only, with no treatment in the left eye. At
this time, manifest refraction was 10.50 6.00 105
in the left eye. In June 2007, 18 months after topography-guided PRK/CXL, UDVA was 20/800 in each
eye. Manifest refraction in the treated right eye had
326
worsened to 12.00 2.50 100 (20/40). Keratometry
was 48.00@29/47.30@119 in the right eye and
47.87@20/46.20@110 in the left eye, and ultrasound
pachymetry was 424 µm in the right eye and 388 µm in
the left eye. Corneal topography revealed flattening in
the difference map in the right eye (Fig 2). The patient
was unhappy with this result and is currently uncomfortable with her anisometropia. She decided not to
proceed with treatment in the fellow eye because she
was unconvinced she had benefited from the topography-guided PRK/CXL procedure. She is currently wearing rigid gas permeable contact lenses in both eyes.
CASE 3
A 26-year-old male helicopter pilot underwent
LASIK in both eyes in June 2004. No operative data
were available. The only data available from the initial
LASIK procedure was that he had “about” 3.00 diopters (D) of myopia in both eyes prior to LASIK. Uncorrected distance visual acuity during the initial 2 years
after LASIK was “good” but then deteriorated in his
right eye. He was subsequently diagnosed with corneal
Management of Corneal Ectasia
After III:
LASIK/Kanellopoulos
& Binder35
Section
Corneal Crosslinking
Figure 2. Case 2. Topography on the left
shows marked inferior steepening before
topography-guided PRK/CXL treatment. The
topography on the right shows the same
cornea 18 months after topography-guided
PRK/CXL with marked flattening of the
corneal ectasia and normalization of the
cornea.
Figure 3. Case 3. Clinical course of the
right eye. A) Topography 3 years after
LASIK demonstrates irregular astigmatism
and marked inferior corneal steepening. Uncorrected distance visual acuity was 20/40 and corrected distance
visual acuity was 20/20 with refraction
of 1.50 2.00 65. B) Topography 3
months after topography-guided PRK/CXL
procedure demonstrates a flatter and
normalized cornea. Uncorrected distance
visual acuity was 20/15. C) Topographic
reproduction of the topography-guided
PRK treatment plan with the WaveLight
platform. This platform plans to remove
tissue in an irregular fashion to normalize
the corneal ectasia seen in Figure 3A. D)
Comparison map, derived from subtracting image B from A, represents the topographic difference in this case 3 months
after the combined treatment. The paracentral flattening is self-explanatory, as
the PRK and CXL have flattened the cone
apex. The superior nasal arcuate flattening represents the actual part-hyperopic
correction, which the topography-guided
treatment has achieved, to accomplish
steepening in the area central to this arc.
Thus, the topography-guided treatment
has normalized the ectatic cornea by flattening the cone apex and at the same
time by “steepening” the remainder of the
central cornea.
ectasia and was offered Intacs (Addition Technology
Inc, Des Plaines, Illinois) or a corneal transplant.
He presented to our institution in September 2007,
3 years after LASIK. Uncorrected distance visual acuity was 20/40 in the right eye and 20/15 in the left eye.
Manifest refraction was 1.50 2.00 65 (20/20) in
the right eye and plano (20/15) in the left eye. Keratometry was 41.62@65/43.62@155 in the right eye and
41.75/42.12@10 in the left eye. Central ultrasound
pachymetry was 476 µm in the right eye and 490 µm
in the left eye.
On September 13, 2007, 39 months after LASIK,
327
Management
ofIII:
Corneal
Ectasia
After LASIK/Kanellopoulos & Binder
36
Section
Corneal
Crosslinking
Figure 4. Case 4. Pentacam comparison of the right eye. The left column shows the data and topography before topography-guided PRK/CXL. The
center column shows the postoperative data and topography. The right column shows the difference (pre- minus postoperative).
combined topography-guided PRK and immediate CXL
was performed in the right eye for 0.50 1.50 60.
The planned laser resection was 35 µm. Prior to treatment, manifest refraction was 1.50 2.00 65; we
reduced the attempted sphere and cylinder, anticipating a subsequent flattening effect of the sequential CXL
procedure. Within 6 months, UDVA improved to 20/25
and 24 months later in September 2009, UDVA improved to 20/15 and the manifest refraction improved
to plano 0.25 05 (20/10). Keratometry in the right
eye was 43.00@97/43.25@07 and ultrasound pachymetry was 441 µm. The difference maps (Pentacam)
before topography-guided PRK/CXL and 2 years postoperative are shown in Figure 3. At 3-year follow-up,
UDVA remains at 20/10.
As a result of the improvement and stability in
visual function, this patient has joined the United
States Air Force as a fighter pilot and is currently serving in active duty.
CASE 4
A 32-year-old woman underwent LASIK in both eyes
in December 2006 for a refractive error of 3.75 D in
the right eye and 4.00 D in the left eye. No other data
328
were available in regard to the surgery. Her vision was
good for 2 years and then started to deteriorate. The
treating surgeon made the diagnosis of corneal ectasia
after LASIK in December 2008.
The patient presented to our institution in January
2009. Uncorrected distance visual acuity was 20/100
in the right eye and 20/20-2 in the left eye. Corrected
distance visual acuity was 20/30 with manifest refraction of 3.25 3.25 45 in the right eye and 20/15
with 0.50 1.25 100 in the left eye. Keratometry
was 46.70@156/44.10@66 and 39.75@155/41.75@65
in the right and left eyes, respectively. Pachymetry
readings were 419 µm and 460 µm in the right and
left eyes, respectively. The diagnosis of corneal ectasia
after LASIK was confirmed by Pentacam in the right eye
(Fig 4, left image). The patient was contact lens–intolerant and opted to undergo topography-guided PRK/CXL
despite the informed consent that the estimated residual
corneal thickness would be 360 µm. This procedure was
performed in February 2009 in the right eye.
The planned correction was 2.50 2.50 45 after
6-mm diameter, 50-µm depth PTK. After ablation,
0.02% MMC in a moistened weck-cell sponge was
used on the stroma for 20 seconds. In January 2010
37
Figure 5. Case 4. Optical coherence
tomography of the central cornea in the
right eye 11 months after topographyguided PRK/CXL. The hyper-reflectivity of
the anterior 2/3 of the cornea suggests (as
reported previously10) the CXL effect (yellow
arrows). The hyper-reflective demarcation
in the middle of the cornea (white arrows)
suggests a thick LASIK flap calculated to
200 µm.
(11 months following treatment), UDVA was 20/30,
and CDVA was 20/20-1 with manifest refraction of
0.50 0.75 141. Keratometry was 43.30 and
42.70@103. Central corneal thickness was 330 µm.
The pre- and postoperative difference map is shown in
Figure 4. Endothelial cell count was unchanged at 20
months (2600 cells/mm2 from 2650 cells/mm2 prior to
application of the Athen’s protocol).
Optical coherence tomography (OCT) of the central cornea in the right eye at 11 months postoperative
shows hyper-reflectivity of the anterior 2/3 of the cornea (Fig 5) demonstrating the CXL effect, which we reported previously when applying similar treatment in
cases of keratoconus.10,11 The hyper-reflective demarcation in the middle of the cornea in this case suggests
a thick LASIK flap calculated to 200 µm by corneal
OCT prior to application of the Athen’s protocol.
SUMMARY OF ALL CASES
A total of 32 eyes in 22 patients with corneal ectasia
occurring 1 to 4 years after LASIK were treated. Preoperative LASIK data were not available in most cases. In
the 5 patients who had available data, no irregularity
on topography or tomography was noted and no other
factor of the LASIK procedure was evaluated to be high
risk (eg, thick flap, residual stromal bed 250 µm).
All patients had documented progression of inferior
steepening in topography and/or tomography maps.
Patient age ranged from 23 to 66 years (mean: 32 years)
with gender divided (women:men=11:11). The mean
measurements representing values after corneal ectasia were confirmed and preoperative to our technique
were as follows. Mean sphere was 7.50 D and mean
preoperative astigmatism was 2.40 D in the 32 eyes.
Mean preoperative to the original LASIK central corneal
thickness was 525 µm in 25 of 32 eyes. The original
LASIK laser resection data were unavailable in 27
eyes, and flap thickness was assumed or calculated using corneal OCT (Optovue, Fremont, California). The
mean residual stromal thickness was 285 µm (range:
210 to 355 µm). Of all 32 ectasia cases, 15 were thought
to have resulted from thicker than planned flaps (mean
residual stromal bed 230 µm), 10 showed signs of corneal
irregularity on preoperative LASIK topography, and 7
had no recognizable risk factor for the development of
corneal ectasia.
All topography-guided PRK procedures were planned
to reduce corneal thickness by a maximum of 50 µm, despite the existing refractive error, to avoid exacerbation
of the ectasia. Most patients (19 patients, 25 eyes) complained of significant pain the first postoperative night
whereas others reported minimal discomfort. Mean
follow-up after the procedure was 27 months.
Uncorrected distance visual acuity improved in 27
eyes, was unchanged in 4 eyes, and worsened in 1 eye;
it was 20/30 or better (0.18 logMAR) in 11 of 32 eyes
and 20/60 or worse (0.47 logMAR) in 2 eyes. Corrected
distance visual acuity was 20/40 or better (0.30
logMAR) in 27 of 32 eyes and 20/25 or better (0.10
logMAR) in 14 eyes.
Mean refractive error decreased by more than 2.50 D
in 27 of 32 eyes, appeared to increase by 0.75 D in 3
eyes, and remained stable in 2 eyes. Mean final spherical equivalent refraction was 1.75 D, indicating the
reduction of cornea irregularity was the target and not
emmetropia.
DISCUSSION
Topography-guided PRK flattens some of the cone
apex (in a fashion similar to an eccentric partial myopic PRK) but simultaneously flattens an arcuate, broader
area of the cornea away from the cone, usually in the
superior nasal periphery; this ablation pattern (see Fig
3C) resembles part of a hyperopic treatment and thus
will cause some amount of steepening or elevation adjacent to the cone, effectively normalizing the cornea.
We have introduced this concept as an effective tissuesparing ablation pattern in highly irregular corneas
such as ectasia in keratoconus.12 It is this core concept
in the topography-guided PRK treatment that makes it,
in our opinion, more therapeutic than refractive. We
have reported7-10 that in theory, the new “flatter” and
329
38
less irregular corneal shape may perform better biomechanically in eyes with corneal ectasia. Specifically, as
the corneal apex becomes a flatter and “broader” cone
(see Figs 3A and 3B), this may redistribute the biomechanical strain from the eye’s intraocular pressure and
other external factors (eg, eye rubbing, blinking, etc).
This effect may be further enhanced with additional
collagen CXL strengthening.
Same-day simultaneous topography-guided PRK and
CXL has several advantages: 1) the combination reduces
the patient’s time away from work, 2) performing both
procedures at the same time with topography-guided
PRK appears to minimize the potential superficial stromal scarring resulting from topography-guided PRK (unpublished observations, December 2005), and 3) when
topography-guided PRK is performed following the CXL
procedure, some of the cross-linked anterior cornea is
removed, minimizing the potential benefit of CXL (unpublished observations, December 2005). We believe it
may be counterintuitive to remove the cross-linked tissue with topography-guided PRK at a later time, as we
are potentially removing a beneficial layer of the stiffer,
cross-linked cornea, which helps maintain the normalized corneal shape. Lastly, 4) by removing the Bowman
layer with topography-guided PRK, this may facilitate
riboflavin solution penetration in the corneal stroma
and less “shielding” of UVA light in its passage through
the cornea, resulting in more effective CXL.
Although a patient with corneal ectasia can have an
improved visual result with the addition of the topography-guided PRK, completely removing significant refractive errors was not our goal. We have placed an arbitrary
“ceiling” of 50 µm to the amount of tissue that we safely
removed centrally, anticipating that further thinning
might destabilize the cornea’s biomechanical integrity,
even following the “stiffening” effect of CXL.
It should be noted that the proprietary riboflavin
solution used was a slightly hypotonic (340 mOsm)
formulation, resulting in slight “swelling” of the cornea intraoperatively (during CXL). This restored the
corneal thickness to approximately 400 µm during
CXL to protect the corneal endothelium; we did not
encounter any corneal endothelial decompensation in
any of the eyes studied herein despite treating cases
with corneal thickness less than the theoretical limit
of 400 µm13 prior to CXL (case 4).
In addition, the laser treatment was applied with
caution, as the refractive effect of CXL (corneal flattening) had to be anticipated. For this reason, we elected
to always attempt a significant undercorrection of both
sphere and cylinder by at least 30%. At a later time, we
hope to more accurately determine the new ablation
rate of CXL stroma.
330
Simultaneous topography-guided PRK and CXL appears to be effective in the rehabilitation of corneal
ectasia after LASIK. The reality of the efficacy of this
treatment has been the reduction of penetrating keratoplasty cases performed for the indication of keratoconus and corneal ectasia after LASIK in our practice
over the past 4 years. The same-day, simultaneous
topography-guided PRK and CXL procedure was easy
to perform, but in some cases, the central epithelial
surface took up to 1 month to regularize and become
lucent. It took from 1 to 4 weeks for us to detect stable
changes in keratometry and topography, which seemed
to match the visual and refractive changes.
The main goal for all refractive surgeons is to try to
eliminate or at least significantly reduce the number of
eyes developing corneal ectasia after PRK and LASIK.
In some eyes, a preexisting condition that may lead to
corneal ectasia with either PRK or LASIK may not be
able to be detected, but by eliminating eyes with abnormal preoperative topography and leaving corneas
with the maximum clinically acceptable residual stromal thickness, we will be able to reduce the number of
eyes that develop corneal ectasia.
Our findings suggest potentially promising results
with same-day, simultaneous topography-guided PRK
and collagen CXL as a therapeutic intervention in
highly irregular corneas with progressive corneal ectasia after LASIK. We have reported herein effective CXL
treatment in cases with minimal corneal thickness
350 µm. Our study demonstrates that we now have
another means of improving the visual and refractive
results of a devastating complication while avoiding or
delaying penetrating keratoplasty.
AUTHOR CONTRIBUTIONS
Study concept and design (A.J.K.); data collection (A.J.K., P.S.B.);
analysis and interpretation of data (A.J.K., P.S.B.); drafting of the
manuscript (A.J.K., P.S.B.); critical revision of the manuscript
(A.J.K., P.S.B.); administrative, technical, or material support (A.J.K.,
P.S.B.); supervision (A.J.K.)
REFERENCES
1. Binder PS. Ectasia after laser in situ keratomileusis. J Cataract
Refract Surg. 2003;29(12):2419-2429.
2. Randleman JB, Russell B, Ward MA, Thompson KP, Stulting
RD. Risk factors and prognosis for corneal ectasia after LASIK.
Ophthalmology. 2003;110(2):267-275.
3. Tabbara K, Kotb A. Risk factors for corneal ectasia after LASIK.
Ophthalmology. 2006;113(9):1618-1622.
4. Klein SR, Epstein RJ, Randleman JB, Stulting RD. Corneal ectasia after laser in situ keratomileusis in patients without apparent
preoperative risk factors. Cornea. 2006;25(4):388-403.
5. Binder PS. Analysis of ectasia after laser in situ keratomileusis:
risk factors. J Cataract Refract Surg. 2007;33(9):1530-1538.
Management of Corneal Ectasia
After LASIK/Kanellopoulos
& Binder39
Section
III: Corneal Crosslinking
6. Hafezi F, Kanellopoulos J, Wiltfang R, Seiler T. Corneal collagen crosslinking with riboflavin and ultraviolet A to treat induced keratectasia after laser in situ keratomileusis. J Cataract
Refract Surg. 2007;33(12):2035-2040.
7. Kanellopoulos AJ.
2007;114(6):1230.
Post
LASIK
ectasia.
Ophthalmology.
8. Kanellopoulos A, Binder PS. Collagen cross-linking (CCL)
with sequential topography-guided PRK: a temporizing alternative for keratoconus to penetrating keratoplasty. Cornea.
2007;26(7):891-895.
9. Ewald M, Kanellopoulos J. Limited topography-guided surface
ablation (TGSA) followed by stabilization with collagen crosslinking with UV irradiation and riboflavin (UVACXL) for keratoconus (KC). Invest Ophthalmol Vis Sci. 2008;49:E-Abstract
4338.
10. Kanellopoulos AJ. Comparison of sequential vs same day simultaneous collagen cross-linking and topography-guided PRK for
treatment of keratoconus. J Refract Surg. 2009;25(9):S812-S818.
11. Krueger RR, Kanellopoulos AJ. Stability of simultaneous topography-guided photorefractive keratectomy and riboflavin/
UVA cross-linking for progressive keratoconus: case reports.
J Refract Surg. 2010;26(10):S827-S832.
12. Kanellopoulos AJ. Managing highly distorted corneas with topography-guided treatment. In: ISRS/AAO 2007 Subspecialty
Day/Refractive Surgery Syllabus. Section II: Ablation Strategies. San Francisco, CA: American Academy of Ophthalmology;
2007:13-15.
13. Spoerl E, Mrochen M, Sliney D, Trokel S, Seiler T. Safety of UVAriboflavin cross-linking of the cornea. Cornea. 2007;26(4):385-389.
331
Ophthalmology
40Clinical
Section
III: Corneal Crosslinking
Dovepress
2012 Subspecialty Day | Refractive
Surgery
open access to scientific and medical research
$ # " ! #%
!7,5**,99;33%,>:8:0*3,
%/,4(5(.,4,5:6-*685,()305+5,99
-8649,<,8,*685,(39*(8805.=0:/:/,:/,59
"86:6*63:8(59,70:/,30(3:676.8(7/?.;0+,+
"#:/,8(7,;:0*8,46+,305.*64)05,+=0:/
9(4,+(?*633(.,5*8699305205.
5(9:(90696/5
(5,33676;369
(9,8<09065.859:0:;:,:/,59
8,,*,(5/(::(5?,(8(5+
%/86(:6970:(3 ,='682 '&$
,='682&50<,890:?,+0*(3$*/663
,='682 '&$
Video abstract
Point your SmartPhone at the code above. If you have a
QR code reader the video abstract will appear. Or use:
%"! # To evaluate the safety and efficacy of combined transepithelial topography-guided
photorefractive keratectomy (PRK) therapeutic remodeling, combined with same-day, collagen
cross-linking (CXL). This protocol was used for the management of cornea blindness due to
severe corneal scarring.
$ # A 57-year-old man had severe corneal blindness in both eyes. Both corneas had
significant central scars attributed to a firework explosion 45 years ago, when the patient
was 12 years old. Corrected distance visual acuity (CDVA) was 20/100 both eyes (OU) with
refraction: 4.00, 4.50 at 135o in the right eye and 3.50, 1.00 at 55o in the left. Respective
keratometries were: 42.3, 60.4 at 17o and 35.8, 39.1 at 151.3o. Cornea transplantation was the
recommendation by multiple cornea specialists as the treatment of choice. We decided prior to
considering a transplant to employ the Athens Protocol (combined topography-guided partial
PRK and CXL) in the right eye in February 2010 and in the left eye in September 2010. The
treatment plan for both eyes was designed on the topography-guided wavelight excimer laser
platform.
#%$# Fifteen months after the right eye treatment, the right cornea had improved translucency and was topographically stable with uncorrected distance visual acuity (UDVA) 20/50
and CDVA 20/40 with refraction 0.50, 2.00 at 5o. We noted a similar outcome after similar
treatment applied in the left eye with UDVA 20/50 and CDVA 20/40 with 0.50, 2.00 at 170o
at the 8-month follow-up.
%# In this case, the introduction of successful management of severe cornea abnormalities and scarring with the Athens Protocol may provide an effective alternative to other
existing surgical or medical options.
(& "# Athens Protocol, collagen cross-linking, cornea blindness, cornea scarring,
photorefractive keratectomy, vision
#"! "$
688,9765+,5*,6/5(5,33676;369
(9,8<09065.859:0:;:,%96*/($:8,,:
:/,598,,*,
%,3
(>
4(03(12)80330(5:<09065*64
#%$( %"%#"!$@===+6<,78,99*64
Dovepress
$$!' "
A 57-year-old man had severe corneal blindness from cornea scarring attributed to a
firework explosion accident that occurred 45 years ago, when the patient was 12 years
old. When we first evaluated the patient in 2009, the uncorrected distance visual acuity
(UDVA) was 20/400 in both eyes, with pinhole improvement to 20/100 in the right
eye and 20/70 in the left eye. There was no improvement to his visual function with
3050*(3!7/:/(34636.?B
A(5,33676;3697;)309/,8(5+30*,59,,6<,,+0*(3"8,99:+%/0909(5!7,5**,99(8:0*3,
=/0*/7,840:9;58,9:80*:,+565*644,8*0(3;9,786<0+,+:/,680.05(3=682097867,83?*0:,+
#!!$%$)!$'
41
Dovepress
""
" !""!%!(" '" ! !(!"%%()&$((&+'#(&!$&#!'&&#'"!&
($((&("#(%!#$#(+*!(,"&%!($&"$&($%$&%-)%&(!"%!$-$&((&("#((&("#(%!#%*$(!($(
"""! "!&"$ "$" "& " "")""&! !"" ""!" '""!$ # "&%"!"M"$*&((##'($&#$"$&%-"%'
#&' $" &"
"$"""! "$"$&%-"%'$(#%$'($%&(*($((#'
&$($$!
"$#('$!!$+#(#"$#('$!!$+#(
!(!"%%()&$(
"$#('$!!$+#(&("#($&#&)!&(-#"%&$*"#(
#(&#'!)#-'*#(+#$"%&($!(!"%%()&$("$#('$!!$+#(&("#($&#&)!&(-#"%&$*"#(#(&#'!)#-'*#(
+#$"%&($(&("#(%!#$#(+*!(,"&%!($&""%!$-$&($%$&%-)%&(!$(
&(-!(-%$($&&(* &(($"-
.+++$*%&''$"
Dovepress
!#!%(!"$!$-
42
Dovepress
! " #%! " !# # #
!!!#
#
spectacle refraction or soft contact lenses, and there was
intolerance to gas-permeable contact lenses in both eyes.
Due to the dense scarring in the right eye, an endothelial cell
count (ECC) was not possible. The ECC was 2000 cells/mm2 in
the left eye. Slit lamp biomicroscopy revealed severe horizontal
central corneal scars in both eyes (see Figure 1A is the right
eye and B the left eye). Dilated fundus examination revealed no
cataracts, normal disks, macula, and retina vessels.
CDVA was 20/100 both eyes (OU) with refraction: 4.00,
4.50 at 135 in the right eye (OD), 3.50, 1.00 at 55 in the
"
"$# ! #
#
$"""!
Dovepress
left eye (OS). Respective keratometries were: 42.3, 60.4 at
17 and 35.8, 39.1 at 151.3.
Tomographic evaluation (Oculyzer II, Wavelight,
Erlangen, Germany) of both eyes is noted in Figure 1D
and shows the thinnest pachymetry of 467 Mm in the right
eye and 448 Mm in the left eye, respectively. Considering
the options of lamellar and penetrating keratoplasty, we
discussed with the patient the possibility of normalizing the
cornea surface, removing some of the scar and additionally
utilizing collagen cross-linking (CXL) to biomechanically
reinforce the thinned corneas and potentially reduce scarring
by suppressing stromal keratocytes.
Potential complications were extensively discussed. The
patient decided to proceed with our recommendation and we
employed the Athens Protocol (combined topography-guided
partial photorefractive keratectomy [PRK] and CXL) in
the right eye in February 2010 and in the left eye 7 months
later, in September 2010. We have previously reported on
this technique1–5 for the management of cornea ectasia. The
excimer laser treatment plan for both eyes was designed on
the wavelight excimer laser platform and is demonstrated in
Figure 1C and H. The treatment plan, pivotal to the application of the Athens Protocol, combines a myopic ablation
over the elevated cornea and a partial hyperopic application
peripheral to the flattened (by scarring), inferior cornea.
This combination treatment enhances the normalization
of the severe irregularity with small ablation (35 Mm) over
the thinnest cornea. Fifteen months after the treatment of the
right eye, the cornea had cleared and was topographically
stable with UDVA at 20/50 and corrected distance visual
acuity (CDVA) of 20/40 with refraction 0.50, 2.00 at 5o.
We noted a similar outcome for the left eye 8 months after
the treatment with UDVA of 20/50 and CDVA of 20/40
with 0.50, 2.00 at 170o.
The postoperative slit-lamp photos of the anterior segment are seen in Figure 1 (right eye: F and left eye: G). His
tomographic keratometry in the right eye has improved
to 44.3, 59.0 at 13.7oand in the left eye to 35.4, 38.4 at
166.3o(Figure 1E shows the right eye on the left and the left
eye on the right). Endothelial cell counts (ECC) were possible
Clinical Ophthalmology
Clinical Ophthalmology is an international, peer-reviewed journal
covering all subspecialties within ophthalmology. Key topics include:
Optometry; Visual science; Pharmacology and drug therapy in eye
diseases; Basic Sciences; Primary and Secondary eye care; Patient
Safety and Quality of Care Improvements. This journal is indexed on
43
Dovepress
postoperatively in the right eye, most likely due to improved
cornea clarity, and were 1600 cells/mm2. The postoperative
ECC in the left eye was measured at 2010 cells/mm2.
The preoperative cornea optical coherence tomography
(OCT) is shown in Figure 2 and the postoperative in Figure 3.
Due to improved visual rehabilitation, the patient has
recently obtained a driver’s license and has assumed a more
independent lifestyle.
In this particular patient, the therapeutic aim of the
topography-guided PRK was to attempt to normalize
the highly irregular corneal surface, and the employment
of the CXL had a two-fold objective: to reduce corneal
scarring by eliminating keratocytes, and to stabilize the
thinner cornea produced by the removal of corneal tissue
with the therapeutic topography-guided ablation.
We feel that in this case the introduction of successful
management of severe cornea abnormalities and scarring
with the Athens Protocol may provide an effective alternative to other surgical options such as lamellar or penetrating
keratoplasty. Further studies in a large cohort of patients
with a longer follow-up are needed to further establish the
effectiveness and safety of this technique.
The author reports no conflicts of interest in this work.
1. Kanellopoulos AJ, Skouteris VS. Secondary ectasia due to forceps
injury at childbirth. management with combined topography-guided
partial PRK and collagen cross-linking (the Athens protocol), followed
by the implantation of a phakic intraocular lens (IOL). J Refract Surg.
In press 2011.
2. Kanellopoulos AJ, Binder PS. Management of corneal ectasia
after LASIK with combined, same-day, topography-guided partial
transepithelial PRK and collagen cross-linking: the Athens protocol.
J Refract Surg. 2011;27(5):323–331.
3. Kr ueger RR, Kanellopoulos AJ. Stability of simultaneous
topography-guided photorefractive keratectomy and riboflavin/UVA
cross-linking for progressive keratoconus: case reports. J Refract Surg.
2010;26(10):S827–S832.
4. Kanellopoulos AJ. Comparison of sequential vs same-day simultaneous
collagen cross-linking and topography-guided PRK for treatment of
keratoconus. J Refract Surg. 2009;25(9):S812–S818.
5. Kanellopoulos AJ, Binder PS. Collagen cross-linking (CCL) with
sequential topography-guided PRK: a temporizing alternative for
keratoconus to penetrating keratoplasty. Cornea. 2007;26(7):891–895.
Dovepress
PubMed Central and CAS, and is the official journal of The Society of
Clinical Ophthalmology (SCO). The manuscript management system
is completely online and includes a very quick and fair peer-review
system, which is all easy to use. Visit http://www.dovepress.com/
testimonials.php to read real quotes from published authors.
!
Dovepress
44
Crosslinking in Pediatric Patients
Paolo Vinciguerra MD, Elena Albè MD, Fabrizio I Camesasca MD, Silvia Trazza
I. Progression of Keratoconus (KC)
V. Safety: Endothelial cell count (see Figure 1)
II. PK Complications in Pediatrics
A. Expulsive choroidal hemorrhage: 2%-3%
B. Wound leak or dehiscence: 2%-10%
C. Inadvertent lens loss: 1%-2%
D. Corneal ulcer and/or infection: 4%-9%
E. Endophthalmitis: 2%
F. New-onset glaucoma: 5%-9%
G. Cataract: 2%-7%
H. Retinal detachment: 3%-5%
I. Phthisis: 4%-13%
Figure 1.
III.Demographic
A. Number of eyes : 66 stage II KC (Amsler-Krumeich
classification)
B. Average age: 15 years (from 9 to 18)
1. Female: 22.7%, or 15 eyes)
2. Male: 77.3%, or 51 eyes
C. Pre SR equivalent: mean -3.15 D ± 3.53 D (from
-13.75 to 2.00)
D. KC progression documented by serial differential
corneal topographies and optical pachymetries.
E. Contralateral not-treated eyes stage I-II used as control.
VI. BSCVA Variation (see Figure 2)
IV. Crosslinking (CXL)
A. 2% pilocarpine drops and antipain meds 30 min
before CXL
Figure 2.
B. Oxybuprocaine hydrochloride 0.2% 5 min before
CXL
C. Laser Test UVA meter
1.Laser λ 370 ± 5 nm
2. Power 3 mW/cm2 (= 5.4 j/cm2)
D. Ricrolin riboflavin 0.1% solution instillation each
minute for 30 min.
E. Riboflavin check absorption in anterior chamber
(flare)
F. UVA light corneal irradiation CBM CSO 7.5 mm Ø
G. Ricrolin instillation 6 times, 5 min. each
H. Bandage soft CL application and levofloxacin eyedrops
VII. Change in BSCVA% Safety (see Figure 3)
Figure 3.
VIII. Correction Sphere and Cylinder (See Figure 4)
XI. SEQ Correction Over Time Stability (See Figure 7)
Figure 7.
Figure 4.
IX. Sphere Variation (See Figure 5)
XII. Pentacam Ambrosio Indices
Table 1. Pentacam Abrosio Indices
ISV
Pre XL
Post XL 3 Years
113.80
103.67
1.28
1.23
1.31
1.30
1.07
1.06
36.17
24.77
0.11
0.10
Surface variance index
IVA
Vertical asymmetry
index
KI
Keratoconus index
CKI
Center keratoconus
index
IHA
Figure 5.
X. Cylinder Variation (See Figure 6)
Height asymmetry
index
IHD
Height decentration
index
RMIN
5.81
P < .02
6.21
Minimum sagittal
curvature
ABR μm
Aberration coefficient
Figure 6.
2.78
2.40
45
46
XIII. Topography Results
XIV. OPD Corneal Navigator Klyce Indices
XV.Conclusions
A. CXL is indicated in pediatric patients with progressive KC.
B. CXL appears to be effective in improving UCVA
and BSCVA by reducing corneal asymmetry and
corneal wavefront aberrations at 3 years follow-up.
C. CXL is a safe treatment for KC, with faster reepithelialization and faster recovery of CCT in pediatric patients.
D. Careful screening and closer follow-up are needed
in pediatric age to avoid faster and more dramatic
progression of the disease.
Rationale and Results of Accelerated Corneal
Crosslinking
John Marshall PhD
N o t es
47
48
Crosslinking Should Not Be Combined With
Primary LASIK
Perry S Binder MD
I. Why would one argue for using collagen crosslinking
(CXL) on every LASIK case?
4. 7, 10, 18, or up to 45 mW/cm2 have been
reported, but no lab or peer-reviewed studies
5. Multiple variations in UVA exposure time
A. Fear of post-LASIK ectasia
B. Fear of inability to detect cases at risk
C. Hope that CXL will be a panacea for ectatic corneal
conditions
a. 30 minutes is the established epithelial
removal exposure time (Dresden Protocol)21
b. 1 to 30 minutes reported without lab or peer
review studies
D. Known adverse effects of epithelial removal with
standard Dresden Protocol CXL1-10
II. What are the known morphologic and clinical effects of
CXL on the cornea?11-16
A.Morphologic
6. Multiple indications for multiple diagnoses, nonstratified cases
a.Keratoconus
b. Forme fruste keratoconus
1. Long-term keratocyte/stromal cell loss
c. Corneal edema
2. Increase in collagen diameter; most crosslinking
between α and β collagen chains and proteoglycan to proteoglycan
d. Corneal infections
e. Postradial keratotomy
f. Pellucid marginal degeneration (PPD)
3. Increased glycation; increased corneal stiffness
4. Slight crosslinking collagen to proteoglycans
5. Cytotoxic threshold levels 3-5 mW/cm2
6. Endothelial cell damage due to reactive oxygen
free radicals caused by riboflavin + UVA
7. Intact tight epithelial tight junctions retard riboflavin absorption
III.
B.Clinical
1. Reduction in Kmax
2. Minimal reduction in MRSE
3. Corneal thinning by OCT and ultrasound
4. Slitlamp demarcation lines
C. Reported complications
1. No effect
2. Under-/no response
3. Corneal scarring
4. Corneal infiltrates
5. Delayed epithelial healing
6. Endothelial cell damage/loss
D. Treatment regimens17-19
1. Multiple variations in riboflavin doses / concentrations / constituents / exposure time
2. Multiple variations in UVA delivery instrumentation and irradiation (see Table 1)
3. 3 mW/cm2 is the current established study irradiation.
What is the current incidence of post-LASIK ectasia?
(What is the risk we are concerned about?)
A. New cases are decreasing
1. Better awareness of risk(s)
2. More predictable flap thickness (femtosecond
lasers) leading to more predictable residual stromal bed thickness (RSBT)
3. More ways to measure postoperative flap and
RSBT thickness (OCT, high-frequency ultrasound)
IV. What are the ways to detect and eliminate eyes at risk
of developing post-LASIK ectasia?
A. Improved topography algorithms/recognition
B. Improved metrics (eg, Optical Response Analyzer
[ORA])
C. Newer biomechanical corneal research to detect
abnormal responses
D. Measurement of epithelial thickness to detect abnormal eyes early
V. What is/are the current ways CXL is performed under a
LASIK flap?22-24
A. Most published research supports significantly more
riboflavin absorption if the epithelium is removed.
B. If one does not believe in epithelium-on riboflavin
delivery, what is the impact of healthy LASIK epithelium on UVA penetration to dye in the LASIK
interface?
C. What is the evidence of riboflavin diffusion from the
LASIK interface in either direction?
49
Table 1. Specifications of CXL Lamps
Manufacturer
IROC
Innocross AG
Sooft Italia
S.p.A.
Opto Global
Pty Ltd.
Avedro, Inc.
Peschke
Meditrade
GmbH
IROC
Innocross AG
Appasamy
Avedro, Inc.
Name of
Device
UV-X1000
Vega
Opto XLink
KXL I System
CCL 365 HE
UV-X2000
CL-UVR
KXL II System
Country of
Origin
Switzerland
Italy
Brazil
United States
Switzerland
Switzerland
India
United States
Wavelength
(nm)
365
370
365
365
365
365
365
365
Intensity of
Illumination
(mW/cm2)
3.0
3.0
0.5-5.0
3.0-45
Up to 18.0
Up to 12
3.0
3 to more
than 90
Variable
Intensity?
No
No
Yes
Yes
No
No
No
Yes
30
Duration of
CXL Treatment
(min)
30
18
3
5
10
30
1-30
Working
Distance (mm)
50
50
50
NS
45 ±5
47
NS
NS
Light Emission
Continuous
NS
NS
Continuous
Continuous
Continuous
NS
NS
Beam Profile
Homogenous
Homgenous
Homogenous
Homogenous
Homogenous
Optimized
NS
Programmable
illumination
Beam Diameter
(mm)
6, 7, and 9
4-9
6-10
9 and 10
7-11
7-11
NS
Up to 14
Weight (kg)
±7
NS
NS
NS
7.5
±7
NS
NS
CE Mark?
Yes
Yes
Yes
Yes
Yes
Yes
NS
Expected in
late 2012
280
24
NS
NS
NS
NS
0
1400
No. of
Treated Eyes
Reported in the
Literature
Abbreviations: CXL indicates collagen crosslinking; NS, not specified.
Reproduced with permission from Cataract and Refractive Surgery Today, ©2012. Cummings AB, Rajpal RK. Illumination lamps for CXL. Cataract & Refractive Surgery
Today, May 2012: 40-41.
D. After LASIK, one is closer to the endothelium by
110-160 μm (possibly more with mechanical microkeratomes). If less riboflavin reaches the deeper
cornea and/or less UVA penetrates the stroma due
to epithelial blockage, what are the implications?
VI. What are the known risks of CXL on a case that has
had post-LASIK ectasia?
A. Limited reports with few cases and short follow-up
periods
B. What results exist that show differences in outcomes
after CXL for keratoconus vs. ectasia.
VII. What are the unknown/suspected risks of performing
routine CXL at the time of a primary LASIK case?
A. Exposure to infection is increased due to increased
surgery and bed exposure time.
B. Long-term risk of deep loss of stromal cells vs. current more superficial cell loss
C. Unknown variation(s) in UVA and riboflavin diffusion and exposure in the middle of the stroma vs.
topical application
D. Unknown effects of CXL on primary and enhancement excimer laser ablation rates
50
E. Unknown effect of routine LASIK CXL on stability of refraction. How would one determine what
portions(s) of postop acuity and refractions arise
from CXL vs. routine wound healing?
F. Unknown risks to endothelium now that one would
be 100-160 μm closer to the endothelium25,26
G. Risks of routine UVA exposure to the conjunctiva
and corneal stem cells27,28
H. Long-term risk to crystalline lens
I. Will routine CXL affect calculations for a subsequent IOL implantation?
J. Lack of a comparison to established CXL treatment
on the ocular surface with and without epithelial
removal
5. Evaluate other more efficient photosensitizers
(eg, verteporfin (Visudyne, Novartis AG)22
Selected References
1. Raiskup F, Hoyer A, Sporl E. Permanent corneal haze after riboflavin-UVA-induced cross-linking in keratoconus. J Refract Surg.
2009; 25:S824-828.
2. Rama P, et al. Acanthamoeba keratitis with perforation after corneal crosslinking and bandage contact lens use. J Cataract Refract
Surg. 2009; 35:788-791.
3. Zamora KV, Males JJ. Polymicrobial keratitis after a collagen crosslinking procedure with postoperative use of a contact lens: a case
report. Cornea 2009; 28:474-476.
4. Mangioris GF, et al. Corneal infiltrates after collagen crosslinking. J
Refract Surg. 2010; 26(8):609-611.
K. Effect on flap adhesion and consequential risk of
superficial trauma and enhancement implications
such as epithelial ingrowth28
5. Sharma N, et al. Pseudomonas keratitis after collagen crosslinking
for keratoconus: case report and review of literature. J Cataract
Refract Surg. 2010; 36(3):517-520.
L. Documented stromal “lines” suggested of level of
crosslinking effect30
6. Abad JC, Vargas A. Gaping of radial and transverse corneal incisions occurring early after CXL. J Cataract Refract Surg. 2011;
37(12):2214-2217.
VIII.Conclusions
A. The risk-benefit ratio for routine CXL for primary
LASIK cases does not justify routine application
because PRK can be used for high-risk cases.
B. It would take a 300-patient study to detect a 1%
incidence of an adverse event. How many cases of
primary CXL on a primary LASIK case would it
take to detect an improvement in the risk of ectasia
considering the required stratification of clinical
data (total corneal thickness, flap thickness, RSBT,
patient age, UVA dose/exposure time, riboflavin
dose, application, exposure time, etc.)?
C. Can we justify its cost to a patient in lieu of what is
known about the current risk/incidence of ectasia?
D. Currently very limited peer reviewed studies of CXL
for a primary LASIK case
E. If a surgeon is concerned about risk and cannot
justify PRK, one can consider a phakic IOL and subsequent PRK.
IX.Recommendations
7. Camesasca FI, Vinciguerra P, Seiler T. Bilateral ring-shaped intrastromal opacities after corneal crosslinking for keratoconus. J
Refract Surg. 2011; 27(12):913-915.
8. Gokhale NS. Corneal endothelial damage after collagen crosslinking treatment. Cornea 2011; 30(12):1495-1498.
9. Rodríguez-Ausín P, et al. Keratopathy after cross-linking for keratoconus. Cornea 2011; 30(9):1051-1053.
10. Ghanem RC, et al. Peripheral sterile corneal ring infiltrate after
riboflavin-UVA collagen cross-linking in keratoconus. Cornea
2012; 31(6):702-705.
11. Kato Y, Uchida K, Kawakiushi S. Aggregation of collagen exposed
to UVA in the presence of riboflavin: a plausible role of tyrosine
modification. Photochem Photobiol. 1994; 59:343-349.
12. Doxer A, et al. Collagen fibrils in the human corneal stroma: structure and aging. Invest Ophthalmol Vis Sci. 1998; 39:644-648.
13. Spoerl E, Huhle M, Seiler T. Induction of cross-links in corneal tissue. Exp Eye Res. 1998; 66:97-103.
14. Spoerl E, Seiler T. Techniques for stiffening the cornea. J Refract
Surg. 1999; 15(6):71-713.
15. Spoerl E, Wollensak G, Seiler T. Increased resistance of crosslinked
cornea against enzymatic digestion. Curr Eye Res. 2003; 29:35-40.
A. Do not perform CXL on a LASIK case until which
time we can determine the risk and benefits.
16. Waring GOI, Huey DA. The drug science of cross-linking. Cataract
& Refractive Surgery Today, May 2012: 42-43.
B. If in doubt about a possible high-risk case, consider
PRK or a phakic IOL.
17. Alhamad TA, et al. Evaluation of transepithelial stromal riboflavin
absorption with enhanced riboflavin solution using spectrophotometry. J Cataract Refract Surg. 2012; 38(5):884-889.
C. Achieve new goals for CXL:
1. Ability to irradiate focal areas of the affected cornea
18. Stojanovic A, Chen X. How to perform CXL. Cataract & Refractive Surgery Today, May 2012: 36-37.
2. Determine depth of treatment accurately
19. Wollensak G, Spoerl E, Seiler T. Riboflavin/ultraviolet-A-induced
collagen crosslinking for the treatment of keratoconus. Am J Ophthalmol. 2003; 135:620-627.
3. Laboratory studies to support shorter exposure
times at greater irradiation
20. Cummings AB, Rajpal RK. Illumination lamps for CXL. Cataract
& Refractive Surgery Today, May 2012: 40-41.
4. Confirm best delivery: epithelium on or off with
or without accelerators
21. Braun E, et al. Riboflavin/ultraviolet A-induced collagen crosslinking in the management of keratoconus. Invest Ophthalmol Vis
Sci. 2005; 46:Abstract 536.
22. Kanellopoulous AJ. Preventing ectasia with cross-linking after PRK
or LASIK. Cataract & Refractive Surgery Today, May 2012: 50-54.
23. Kampik D, et al. Influence of corneal collagen crosslinking with
riboflavin and ultraviolet-A irradiation on excimer laser surgery.
Invest Ophthalmol Vis Sci. 2010; 53:3929-3934.
24. Hafezi F, et al. Corneal collagen crosslinking with riboflavin and
ultraviolet A to treat induced keratectasia after laser in situ keratomileusis. J Cataract Refract Surg. 2007; 33:2035-2040.
25. Wollensak G, et al. Endothelial cell damage after riboflavinultraviolet-A treatment in the rabbit. J Cataract Refract Surg. 2003;
29:1786-1790.
26. Gokhale NS. Corneal endothelial damage after collagen crosslinking treatment. Cornea 2011; 39:1495-1498.
27. Vimalin J, Gupta N, Jambulingam M, et al. The effect of riboflavinUV-A treatment on corneal limbal epithelial cells: a study on human
cadaver eyes. Cornea 2012; 31(9):1052-1059.
28. Thorsrud A, Nicolaissen B, Drolsum L. Corneal collagen crosslinking in vitro: inhibited regeneration of human limbal epithelial cells
after riboflavin ultraviolet-A exposure. J Cataract Refract Surg.
2012; 38:1072-1076.
29. Littlechild SL, et al. Fibrinogen, riboflavin and UVA to immobilize
a corneal flap: conditions for tissue adhesion. Invest Ophthalmol
Vis Sci. 2012 June 26; 53(7):4011-4020. ARVO e-abstracts.
30. Koller T, et al. Scheimpflug imaging of corneas after collagen crosslinking. Cornea 2009; 28:510-515.
51
52
Advocating for Patients
2012 Advocating for Patients
Stephanie J Marioneaux MD
Ophthalmology’s goal in protecting quality patient eye care
remains a key priority for the Academy. As health care delivery
evolves, with narrowing practice margins making efficiency
of increasing importance, all Eye M.D.s should consider their
contributions to three funds as (a) part of their costs of doing
business and (b) their individual responsibility in advocating for
patients:
• OPHTHPAC® Fund
• Surgical Scope Fund (SSF)
• State Eye PAC
While the Academy fully supports the concept of an “integrated eye care delivery team,” it also remains firm on defining
appropriate roles for the various eye care providers as demonstrated via its Surgery by Surgeons campaign.
OPHTHPAC® Fund
OPHTHPAC is a crucial part of the Academy’s strategy to protect and advance ophthalmology’s interests in key areas including physician payments in Medicare as well as protecting ophthalmology from federal scope of practice threats. Established
in 1985, today OPHTHPAC is one of the largest and most successful political action committees in the physician community.
In 2010, Politico highlighted OPHTHPAC as one of the most
successful health PACs in strategic giving in the 2010 election.
By making strategic election campaign contributions and independent expenditures, OPHTHPAC helps us elect friends of ophthalmology to federal leadership positions, ultimately resulting
in beneficial outcomes for all Eye M.D.s. For example, 20 physicians, including 2 ophthalmologists, were elected to Congress
in 2010. Thanks to the OPHTHPAC contributions made in the
2007-2010 timeframe, ophthalmology realized an 8% increase
in Medicare payments (other specialties experienced significant
decreases). Among the significant impacts of OPHTHPAC:
• Averted significant cuts to Medicare payments due to the
Sustainable Growth Rate (SGR) formula
• Protected Practice Expense increases for ophthalmology
when attacked by other specialties
• Exempted ultrasound from imaging cuts
• Protected the in-office ancillary services exception
• Secured physician exemption from Red Flag (creditor)
rules
• Secured reversal of CMS decision to cut reimbursement for
Avastin
• Delayed Medicare penalties dates in health reform law
• Secured appointment of full-time ophthalmology national
program director in the VA
Leaders of the American Society of Cataract & Refractive
Surgery (ASCRS) are part of the American Academy of Ophthalmology’s Ophthalmic Advocacy Leadership Group (OALG),
which has met for the past five years in the Washington, DC,
area to provide critical input and to discuss and collaborate on
the American Academy’s advocacy agenda. As 2012 Congressional Advocacy Day (CAD) partners, the ASCSR ensured a strong
presence of cataract and refractive specialists to support ophthalmology’s priorities as over 350 Eye M.D.s had scheduled CAD
visits to members of Congress in conjunction with the Academy’s
2012 Mid-Year Forum in Washington, DC. The ASCRS remains
a crucial partner to the Academy in its ongoing federal and state
advocacy initiatives.
Surgical Scope Fund (SSF)
At the state level, the Academy’s Surgery by Surgeons campaign
has demonstrated a proven track record. While Kentucky was
an outlier, the Academy’s SSF has helped 33 state / territorial
ophthalmology societies reject optometric surgery language. The
Academy’s Secretariat for State Affairs, in partnership with state
ophthalmology societies, battled optometry across the country
in 2011 to protect patient access to quality medical surgical care.
Several ophthalmic subspecialty societies also provided critical
support when called upon. Although there was a setback in Kentucky, ophthalmology derailed O.D. surgery initiatives in 7 states
and achieved its first proactive victory in Oklahoma.
The SSF is a critical tool of the Surgery by Surgeons campaign
to protect patient quality of care and our collective fund to
ensure that optometry does not legislate the right to perform surgery. The Academy relies not only on the financial contributions
via the SSF by individual Eye M.D.s but also the contributions
made by ophthalmic state, subspecialty and specialized interest
societies. The ASCRS contributed to the SSF in 2011 and the
Academy counts on its contribution in 2012.
With last year’s passage of legislation in Kentucky that
allowed optometrists to perform laser surgery, the American
Academy of Ophthalmology’s partnership with ophthalmic
subspecialty and state societies in the Surgery by Surgeons campaign became even more important in protecting quality patient
eye care across the country. The Academy’s Secretariat for State
Affairs redoubled its efforts with “target” states, including Tennessee and others, while adding professional media training to
the resources provided to prepare Eye M.D.s in advance of any
anticipated legislative or regulatory move.
State Eye PAC
State ophthalmology societies can not count on the SSF alone—
equally important is the presence of a strong state Eye PAC,
which provides financial support for campaign contributions and
legislative education to elect ophthalmology-friendly candidates
for the state legislature. The Secretariat for State Affairs strategizes with state ophthalmology societies on target goals for state
eye PAC levels.
Action Requested: Advocate for Your Patients!!
PAC contributions are necessary at the state and federal level to
help elect officials who will support the interests of our patients.
Academy SSF contributions are used to support the infrastructure necessary in state legislative / regulatory battles and for
public education. Contributions across the board are needed. SSF
Advocating for Patients
53
Surgical Scope Fund
OPHTHPAC® Fund
State EyePAC
Scope of practice at the state level
Ophthalmology’s interests at the federal level –
Support for candidates for US Congress
Support for candidates for State House and Senate
Lobbyists, media, public education,
administrative needs
Campaign contributions, legislative education
Campaign contributions, legislative education
Contributions: Unlimited
Contributions: Limited to $5,000
Contribution limits vary based on state regulations
Contributions are 100% confidential
Contributions above $200 are on the public
record
Contributions are on the public record
contributions are completely confidential and may be made with
corporate checks or credit cards—unlike PAC contributions,
which must be made by individuals and which are subject to
reporting requirements.
Please respond to your Academy colleagues who are volunteering their time on your behalf to serve on the OPHTHPAC*
and SSF** Committees, as well as your state ophthalmology
society leaders, when they call on you and your subspecialty society to contribute. Advocate for your patients now!
*OPHTHPAC Committee
Donald J Cinotti MD (NJ) – Chair
Charles C Barr MD (KY)
William Z Bridges Jr MD (NC)
Dawn C Buckingham MD (TX)
Robert A Copeland Jr MD (Washington DC)
James E Croley III MD (FL)
Anna Luisa Di Lorenzo MD (MI)
Andrew P Doan MD PhD (CA)
Warren R Fagadau MD (TX)
Michael L Gilbert MD (WA)
Alan E Kimura MD (CO)
Lisa Nijm MD JD (IL)
Andrew J Packer MD (CT)
Andrew M Prince MD (NY)
Kristin E Reidy DO (NM)
Ruth E Williams MD (IL)
Ex-Officio Members:
Cynthia A Bradford MD (OK)
Gregory P Kwasny MD (WI)
Michael X Repka MD (MD)
**Surgical Scope Fund Committee
Thomas A Graul MD (NE) – Chair
Arezio Amirikia MD (MI)
Ronald A Braswell MD (MS)
Kenneth P Cheng MD (PA)
John P Holds MD (MO)
Bryan S Lee MD PhD (MD) – Consultant
Stephanie J Marioneaux MD (VA)
Andrew Tharp MD (IN)
Ex-Officio Members:
Cynthia A Bradford MD
Daniel J Briceland MD
54
Transepithelial and Epithelium-off Riboflavin-UVA
Crosslinking: Biological and Biomechanical Responses
in Rabbits
Presenting Author: Steven E Wilson MD
Coauthors: Brian Armstrong MD, Michelle Lin MD, Matt
Ford BA, Marcony R Santhiago MD, Vivek Singh PhD, Greg
Grossman PhD, Vandana Agrawal MS, Abhijit Sinha Roy PhD,
William J Dupps MD
Purpose: To compare the effects of different riboflavin-UVA
crosslinking methods in rabbits. Methods: Sixty rabbits were
divided into 4 treatment groups: (1) standard epithelium-off,
(2) tetracaine transepithelial, (3) benzalkonium chloride (BKC)
transepithelial, and (4) femtosecond laser-assisted transepithelial
corneal crosslinking (CX). CXL parameters were 0.1% riboflavin, UVA (370-nm) irradiance 3 mW/cm2 for 30 min. Eyes were
analyzed at 24 hours and 2 months after treatment. The TUNEL
assay was performed to detect the extent of stromal cell death.
The corneal stiffening effect of riboflavin-UVA crosslinking
was quantitated using OCT elastography. Results: At 24 hours
after CXL, stromal cell death extended full corneal thickness
with both standard epithelium-off CXL and femtosecond laserassisted CXL (including endothelial cell death in some corneas)
but only approximately 1/3 stromal depth after BKC transepithelial CXL. Negligible stromal cell death was detected with tetracaine transepithelial CXL. The BKC transepithelial CXL group
(horizontal/axial displacement 0.010 ± 0.002) had significantly
more stiffening measured with OCT elastography than the epithelium-off CXL (0.023 ± 0.004) or femtosecond laser-assisted
CXL (0.020 ± 0.004) groups. The tetracaine transepithelial CXL
group showed minimal stiffening (0.029 ± 0.006). Conclusions:
In the rabbit model, BKC transepithelial CXL produces more
corneal stiffening than standard epithelium-off CXL or femtosecond laser-assisted CXL, despite producing significantly less stromal cell death. The tetracaine transepithelial CXL group showed
no evidence of stromal cellular response and had little stiffening
effect compared to the other crosslinking groups.
Effect of Collagen Crosslinking on the Limbal Stem
Cells
Presenting Author: Olivier Richoz MD
Coauthor: Farhad Hafezi MD
Purpose: Some corneal disorders, like pellucid marginal degeneration, require UVA irradiation close to the limbus. Currently,
many surgeons cover the limbus and the peripheral cornea,
which might compromise the therapeutic effect. We have tested
the effect of collagen crosslinking (CXL) on the stem cells of
the corneal limbus in an experimental setting. Methods: We
performed epithelial-off CXL in male New Zealand white rabbits using (1) various irradiation areas (central cornea alone,
whole cornea including the limbus), (2) UVA light at 365 nm,
(3) various intensities (3 mW, 10 mW), and (4) various irradiation durations (10 min, 30 min). The right eye was the treated
eye and the left eye was the control (same treatment excepted
UV illumination). Investigations include light microscopy,
immunohistochemistry, Western blotting, and rt-PCR. Results:
Preliminary data demonstrate an absence of thrombosis of limbic
vessels and a complete re-epithelialization of the cornea within
48 hours. Surprisingly, the re-epithelialization time was not
superior in cornea-limbus totally irradiated with UV and was not
superior with long time and high-intensity irradiation. Conclusions: Direct irradiation of the corneal limbus using the standard
parameters (3 mW for 30 min) does not affect the efficacy of reepithelialization. This result is the same with 10 mW for 10 min
and also 10 mW for 30 minutes.
Results of Collagen Crosslinking With Riboflavin in
Children with Progressive Keratoconus
Presenting Author: Mahipal S Sachdev MBBS
Coauthors: Ramendra Bakshi MS, Charu Khurana MS, Ritika
Sachdev MS, Hemlata Gupta MS
Purpose: To assess the safety and efficacy of results of corneal
collagen crosslinking with riboflavin using ultraviolet-A light
in children with keratoconus. Methods: Twenty-five eyes of 15
children with progressive keratoconus aged between 9-16 years
were included in this retrospective study. Ocular examination
included BCVA, dilated refraction, and corneal topography
(Pentacam) at each visit. All children were treated with riboflavin
with UVA light under topical or general anesthesia. All children
completed at least 1 year of follow-up. Results: Mean age of the
children was 13.86 + 3.02 years (range: 9-16 years). 57.14% of
children had vernal keratoconjunctivitis-associated keratoconus.
Mean follow-up period was 24.57 months (range: 1 to 3 years).
Mean preoperative keratometry was 51.96 + 5.75 D, whereas
mean postoperative keratometry was reduced to 48.73+ 3.83 D.
Mean preoperative pachymetry was 455.8+ 54.5 microns, which
changed to 400 + 41.47 microns postoperatively. At the last
follow-up, improvement in BCVA by 1 line or more was noted
in all eyes (100%). There were no complications noted. Conclusions: Collagen crosslinking with riboflavin is a safe and effective
procedure in children with progressive keratoconus. The results
show a stabilization and improvement in keratoconus in terms
of BCVA and corneal curvature after collagen crosslinking in
children.
Forme Fruste Keratoconus Detection by Corneal
Epithelial Thickness Mapping with OCT
Presenting Author: David Huang MD PhD
Coauthor: Yan Li PhD
Purpose: To detect forme fruste keratoconus (FFK) by analyzing corneal epithelial thickness maps obtained with Fourierdomain OCT. Methods: A 26-kHz Fourier-domain OCT system
(RTVue, Optovue, Inc.) with 5-µm axial resolution was used to
scan the corneas of FFK and normal subjects. The central 6-mm
diameter of the cornea was scanned on 8 meridians. A computer
algorithm was developed to automatically map the corneal
epithelial thickness and calculate 5 diagnostic variables: minimum, superior-inferior (S-I), minimum maximum (MIN-MAX),
root-mean-square variation (RMSV), and root-mean-square
pattern deviation (RMSPD). Two scans were obtained from each
eye. The area under the receiver operating characteristic curve
(AROC) was used to evaluate diagnostic accuracy. Results: Seventeen eyes of 17 FFK patients and 17 eyes of 17 normal subjects
were included in the study. Epithelial maps of FFK subjects were
characterized by apical thinning with surrounding thickening.
Compared to normal eyes, FFK eyes had significantly (P < .01)
lower minimum thickness (42.1 ± 5.4 vs. 46.0 ± 3.3 µm, mean
± population SD), greater S-I (3.0 ± 4.9 vs. -1.5 ± 2.0 µm), more
negative minimum maximum (-15.5 ± 7.1 vs. -8.4 ± 4.4 µm),
greater RMSV (4.1 ± 1.9 vs. 2.0 ± 1.1 µm), and larger RMSPD
(0.104 ± 0.024 vs. 0.027 ± 0.009). The AROC values were 0.73
(minimum), 0.77 (S-I), 0.82 (MIN-MAX), 0.84 (RMSV), and 1.0
(RMSPD). Conclusions: The abnormal epithelial pattern in early
keratoconus could be detected with very high accuracy using the
RMSPD variable measured by Fourier-domain OCT.
Management of Ectasia Post Corneal Refractive
Surgery
Presenting Author: Jan A Venter MD
Coauthors: Steven C Schallhorn MD
Purpose: To analyse the visual outcomes and method of final
visual correction in eyes with corneal ectasia after laser in situ
keratomileousis (LASIK) and photorefractive keratectomy (PRK)
Methods: Retrospective data of 51 eyes of 41 patients with corneal ectasia were reviewed in this study. Forty-eight eyes underwent LASIK (38 eyes Microkeratome, 10 eyes Intralase) and
three eyes underwent PRK. Collagen crosslinking was performed
in all cases as a first step. Fifteen eyes required an Intacs ring due
to the irregular astigmatism affecting corrected distance visual
acuity (CDVA). Once stability of topography and refraction was
achieved, further refractive procedure was considered to correct
remaining refractive error. PRK was performed in eyes where
ablation depth did not exceed 50 microns (17 eyes) and phakic
intraocular lens was considered in patients with higher refractive
error (18 eyes). Results: Data prior to crosslinking were compared to the data of the final visit to the clinic. The mean sphere
changed from +0.88 ± 1.46 D to +0.53 ± 0.69 D. The mean
refractive cylinder reduced from -2.76 ± 1.18 D preoperatively to
-1.09 ± 0.86 D postoperatively. Unaided visual acuity (UDVA)
improved from 0.50 ± 0.30 LogMAR to 0.14 ± 0.17 LogMAR.
67% of eyes achieved postoperative UDVA of 6/7.5 or better
and 88% achieved postoperative CDVA of 6/7.5 or better. Two
eyes needed a referral for corneal graft. Conclusion: Functional
unaided visual acuity can be restored in patients who develop
55
corneal ectasia, however, multiple procedures might be required
to achieve this goal.
Outcomes of Corneal Collagen Crosslinking for
Treatment of Keratoconus and Ectasia After LASIK
Presenting Author: Sumitra S Khandelwal MD
Coauthors: J Bradley Randleman MD, R Doyle Stulting MD
PhD
Purpose: To evaluate and compare 1-year outcomes of corneal collagen crosslinking (CXL) for keratoconus (KCN) and
post-LASIK ectasia (ectasia). Design: Prospective, randomized,
controlled clinical trial. Methods: CXL was performed in eyes
with keratoconus or ectasia. Outcomes included uncorrected
(UDVA), corrected (CDVA) distance visual acuities, maximum
keratometry (Kmax), average keratometry (Kavg), and corneal
thickness (CCT). Results: One-year data of 130 eyes (ectasia =
56, keratoconus = 74) were included. In the combined cohort
there was flattening Kmax (-1.20 D, P = .03) at 12 months compared to baseline. In the subgroups, there was flattening of Kmax
in the ectasia group (-0.82 D, P = .31) and KCN group (-1.20 D,
P = .08). In the cohort there was improvement in UDVA (+6.35,
P = .01) and CDVA (+7.78, P < .01). In the ectasia group, CDVA
was improved compared to pretreatment (+5.70; P = .03). In the
KCN group, UDVA (+6.35, P = .01) and CDVA (+7.78, P < .01)
improved. CDVA with contact lens showed a 35% improvement
in the ectasia group by 12 months and a 12% improvement in
the keratoconus group (P = .83). There was a significant increase
in change in UDVA at 12 months compared to baseline in the
KCN compared to ectasia (P = .02). Excluding patients whose
Kmax steepened after treatment, patients in the cohort who had
a baseline Kmax greater than or equal to 54 D were more likely
to obtain flattening of 1 D after treatment (P = .01). There was
no difference between change in Kmax or endothelial cell count
in patients who required hypotonic riboflavin for intraoperative
CCT < 400 microns compared to standard Dextran in the cohort
nor the subgroups. Conclusions: CXL is an effective treatment
for both keratoconus and ectasia after LASIK.
56
Topography-Guided Photorefractive Keratectomy
and Crosslinking for Ectasia After LASIK
Presenting Author: Simon P Holland MD
Coauthor: David TC Lin MD
Purpose: To evaluate early results of topography-guided photorefractive keratectomy (TG-PRK) with simultaneous collagen
crosslinking (CXL) for ectasia after LASIK. Methods: Patients
with post-LASIK ectasia underwent TG-PRK with simultaneous CXL. Twenty-five eyes of 29 were treated using Allegretto
WaveLight laser (AW) and 4 eyes with IVIS laser. Both of them
used transepithelial PRK and custom topographical neutralization technique (TNT) . Pre- and postoperative assessment of
symptoms, UCVA, BCVA, manifest refraction (MR) predictability, and safety were assessed. Results: Thirteen of 19 eyes treated
by the AW laser had sufficient data at 6 months for analysis:
54% (7 of 13) showed UCVA of =20/40 compared to 46% (6 of
13) preoperatively. Five of 13 gained 2 or more lines of BCVA
while 1 of 13 lost 2 or more. Mean reduction in astigmatism
(RIA) was 2.69 D. For the patients treated by the IVIS laser, 3
of 4 had UCVA of =20/40 compared to 2 of 4 preoperatively.
One of 4 gained 2 or more lines of BCVA, with the others losing
1 line or more. Mean (RIA) was 1.50 D. Combining results for
both lasers, all but 3 patients symptomatically improved. Conclusions: Early results demonstrate that custom TNT TG-PRK
with CXL shows promise as an effective and safe treatment for
post-LASIK ectasia across two laser platforms. All but 3 patients
had improved symptoms. Most patients treated by AW laser
recovered UCVA of 20/40 and also improved BSCVA.
Collagen Crosslinking and Topography-Guided
Customized Ablation Treatment for Keratoconus
and post-LASIK Ectasia
Presenting Author: Tenley N Bower MD
Coauthors: Salim Korban, Dwight Silvera MD, Eser Adiguzel
PhD, Mark Cohen MD, Avi Wallerstein MD
Purpose: To determine efficacy, safety, and stability of corneal
collagen crosslinking (CXL) combined with topography-guided
customized ablation treatment (TCAT) excimer laser corneal
surface ablation for keratoconus and post-LASIK ectasia. Methods: Outcomes review of patients undergoing CXL + TCAT.
One-, 2-, 3-, 6-, and 12-month post-op MRSE, cylinder, UDVA,
CDVA, + Kmax were compared to preop measurements. RMANOVA and Holms Sidak post-hoc tests were used. Subjective
quality of vision questionnaire was administered. Results: 125
eyes were treated (100 keratoconus, 25 ectasia). There was a significant improvement in UDVA (1.1 ± 0.7 vs. 0.6 ± 0.5 logMAR,
P < .001), MRSE (-3.04 ± 3.06 vs. -1.60 ± 3.11 D, P < .001) and
reduction in cylinder (-3.77 ± 2.29 vs. -2.02 ± 2.03 D, P < .001).
Cumulative postop UDVA of 20/30, 20/40, and 20/50 or better
in 24%, 38%, and 47% of eyes, respectively, compared to preop
CDVA of 48%, 66%, and 76%, respectively. 12% at 12 months
lost 2 or more lines of Snellen CDVA, 13% at 12 months lost
1, and no change in 33% at 6 months and 25% at 12 months.
Postop Kmax had no significant differences at 1, 2, 3, 6, and 12
months (P = .17). 11.1% of respondents rated their vision as
worse than before surgery, 24.4% as no change, 64.4% as better. Corrected and uncorrected vision was rated 6.7 ± 1.2 and
6.0 ± 2.6 at 6 months and 8.0 ± 1.4 and 4.6 ± 2.6 at 12 months
compared to preop 5.3 ± 2.6 and 3.5 ± 2.1, respectively. Conclusion: CXL with TCAT improves UDVA and reduces cylinder
magnitude, with high patient satisfaction that improves up to
12 months. There was no further progression of keratoconus or
post-LASIK ectasia.
Five-Year Outcomes of Intracorneal Ring Segments
for the Treatment of Keratoconus: Stability Analysis
Presenting Author: Jorge L Alio MD PhD
Coauthors: Alfredo Vega-Estrada MD, Neus Burguera-Gimenez
MS, Luis F Brenner MD
Purpose: To report long-term visual acuity outcomes and optical
quality of the cornea of eyes implanted with intracorneal ring
segment (ICRS) in order to evaluate the stability of the procedure
after a follow-up period of 5 years. Methods: A retrospective
study of 51 consecutive keratoconic eyes of 35 patients treated
with ICRS (age range: 15-56 years) that were included in the
general group. This group was divided into 2 subgroups: Group
A, 29 eyes of patients with ages ≤ 29 years old and Group B, 22
eyes with ages > 29 years old. Uncorrected distance visual acuity
(UDVA), best corrected distance visual acuity (CDVA), manifest
refraction, corneal topographic and aberrometric analysis were
evaluated preoperatively and postoperatively during a period of
5 years in all cases. Results: Significantly better values of UDVA,
CDVA, spherical equivalent, and mean keratometry were found
after 6 months (P < .05). Five years after the surgical procedure
these parameters remained unchanged and statistically insignificant (P = .31). A slight regression of 0.97 D was observed
between 6 months and 5 years. However, this regression was not
statistically significant (P = .39). Anterior corneal aberrometric
outcomes decreased, but the changes were not statistically significant (P = .10). Conclusions: The ICRS provided an improvement
on the refractive and topographic status. No statistical significance was found between both age groups. Although a regression was observed at 5 years, the changes induced in the corneal
tissue are expected to be stable throughout a long period of time
regardless of the patient’s age.
57
Effect of Hinge Location on Dry Eye Symptoms and
High-Order Aberration Following Femtosecond
Laser-Assisted LASIK
Phakic IOL Explantation: Results and Outcomes in
140 Cases
Presenting Author: Choun-ki Joo MD
Coauthors: Bader T Toffaha MD, Jorge L Alio MD PhD, Rafael
I Barraquer PhD, Pablo Peña Garcia MS, Neus BurgueraGimenez MS
Purpose: To evaluate the refractive outcomes after phakic IOL
(P-IOL) explantation surgery and to investigate the safety and
efficacy of the explantation surgery. Methods: Multicentric retrospective study of explanted P-IOL cases belonging to Vissum
Corporation, Alicante and Centro de Oftalmologia Barraquer,
Barcelona, Spain, was carried out. The study included anglesupported P-IOLs, iris-fixated P-IOLs, and posterior chamber
P-IOLs. The information belonging to the explantation surgery
was studied and analyzed. Results: A total of 140 eyes of 126
patients have been studied. Patients’ mean age when explantation surgery occurred was 44.1 (25-77) years .The mean CDVA
was improved from 0.49 to 0.64, and the mean spherical equivalent improved from -5.1 to +0.7 D after the explantation surgery.
Statistically significant differences (P < .001, Student test) were
observed between preop and postoperative data for both CDVA
and spherical equivalent. The main explantation surgeries performed were bilensectomy with 101 eyes (72.2%), phakic IOL
exchange with 22 eyes (15.7%), and P-IOL removal with 10 eyes
(7.1%). Combined surgery of bilensectomy and keratoplasty
was performed in 3 eyes (2.1%). The main implanted lenses after
the explantation surgery were Alcon AcrySof lenses in 86 eyes
(61.3%), Acri.Tec AcriSmart lens in 14 eyes (10%), and Alcon
CZ70BD lens in 6 eyes (4.3%). Conclusion: In our study, phakic
IOL explantation surgery seemed a very effective and safe reversible refractive approach, with excellent visual outcomes. The
option of explantation surgery is always an available surgical
choice for the refractive surgeon interested in different anatomical types of phakic IOL implantation.
Coauthor: Dong-Jin Chang MD
Purpose: To compare the differences in dry eye symptoms
and high-order aberration (HOA) given the clinical results of
wavefront-guided LASIK when a corneal flap was created in
either the temporal side or the superior side with femtosecond
laser. Methods: A retrospective study was performed to compare
corneal sensitivity, tear breakup time, anesthetized Schirmer test,
UCVA, refraction, and HOA preoperatively and at 1 week and
2 and 6 months postoperatively. The parameters were compared
between the temporal hinge group and the superior hinge group.
Results: Forty eyes of 20 patients (13 women and 7 men) of the
temporal hinge group and 40 eyes of 20 patients (12 women
and 8 men) of the superior hinge group who underwent LASIK
for myopia or myopic astigmatism with femtosecond flaps were
evaluated. No significant difference of corneal sensitivity, tear
breakup time, anesthetized Schirmer test, UCVA, refraction (in
terms of spherical equivalent), and HOA (in terms of RMS) was
observed between the groups at 6 months postoperatively (P =
.45, .64, .48, .39, and .38, respectively, Mann Whitney U test).
Conclusion: Dry eye symptoms and HOA after femtosecond
assisted and wavefront-guided LASIK were not affected by the
location of the hinge.
Initial Results of a New Wavefront-Guided LASIK
Procedure
Presenting Author: Steven C Schallhorn MD
Purpose: To report the initial results of new wavefront-guided
procedure for LASIK. Methods: Twelve eyes of 6 patients underwent primary wavefront-guided femtosecond LASIK using a
novel aberrometer and followed for 1 week. Results: The mean
age of subjects was 26.2 ± 6.16 (18 to 37). The preop mean
sphere -1.00 ± 2.52 D (range: -3.50 to +4.00 D) was reduced to
-0.05 ± 0.28 D (range: -0.50 to +0.50 D). Likewise, the mean
preop cylinder -1.72 ± 1.61 D (range: -0.25 to -4.75 D) was
reduced to -0.08 ± 0.12 D (range: 0.00 to -0.25 D). The MSE of
all eyes postop were within 0.50 D. No eye lost more than 1 line
of BCVA, and 67%, 92%, and 100% of eyes achieved 20/16,
20/20, and 20/25 or better UCVA, respectively. Conclusion: Initial results of wavefront-guided LASIK using a new aberrometer
to correct hyperopia and myopia with a large range of astigmatism is favorable. Significantly more treatments with longer
follow-up is progressing.
Presenting Author: Felipe A Soria PhD
58
Keynote Lecture
Presbyopic Lenses: Where Are We Headed?
Daniel S Durrie MD
I. Where Presbyopia Is Headed: Context
A. Today there are already many, many more presbyopes than cataracts.
1. Cataract surgeries performed per year: 3.4 million
2. Of these, 400,000 are presbyopic lenses.
3. Presbyopic population = 243.2 million eyes
(according to 2010 census data: even more by
today)
2. Concerned about health, self-improvement, selfeducation
3. Access to many information sources
4. Highly reliant on near and intermediate distance
5. Expectation for excellent vision from best technology
6. Have seen parents go through cataract surgery
4. When we lock into thinking of presbyopic
correction only in the form of premium lens
upgrades for cataract surgery, we are missing a
quarter of a billion eyes out there right now.
C. What do they want presbyopic treatment to look
like? The Apple Computer of surgery:
Figure 1.
1. Choices, options, multiple solutions, customized
for the individual, but easy to understand and
use
a. Constant innovation: new model each year,
better each year, offers most up to date
b. We must be willing and able to learn/adopt
newest technology quickly.
2. Seamless, invisible to others, yet with dramatic
effect (Wow!)
3. Rapid treatment, available on demand without
long waits or extended preparation
4. Quick recovery, no downtime, no need for
follow-up
5. Predictable outcome, works on first try
6.Safety
7.“Trustworthiness”
B. We need to expand our view further still: Include
the “soon to be presbyopic.”
a. We are in a world of skeptics, with no trust
for doctors, institutions, companies.
1. Steady stream: In next 20 years, an additional
164 million eyes
b. Treatment has not only to be good clinically,
but to match a moral/ethical code.
2. Even less likely to accept reading glasses
3. Even more likely to need near vision (increasing
reliance on tablets, smartphones)
a. People always want lower cost, but if something is good people will pay for it.
4. More ready and quick to adopt new technology
5. In next 20 years, total market = 407.2 million
eyes = almost half a billion.
b. If we can meet all of the above, then cost will
not be issue (like Apple products).
II. What will presbyopic patients want?
A. This will guide where we are headed; must address
their needs.
B. Imagine 45-year-olds in the throes of onset of presbyopia.
1. Busy, active, height of demands of career and
family, limited time
8.Cost
III. What do we need to do to get there?
A. Expand our vision: include all presbyopes and prepresbyopes in planning
1. 407.2 million eyes
2. Almost a half billion eyes in the United States
alone
Keynote Lecture
B. Meet the needs set out above: multiplicity of solutions
a. Corneal lasers
b. Corneal inlays
c. Multifocal IOLs
d. Accommodating IOLs
e.Combinations
b. Conquering the capsule
i. eliminate Yag: While good for us, it’s just
another procedure / cost / time / source of
anxiety for the patient.
ii. intraoperative treatments to prevent posterior capsule opacification
iii. technology to manage effective lens position, rather than be at the mercy of capsular healing
1. We will hear about current solutions from the
following speakers:
c. Continue to seek ways of decreasing complications
2. Cannot rely on any one therapy
a. Need to continue to develop each one
b. Need to continue to develop new therapies in
addition
i. scleral therapies?
ii. nonsurgical “acceptable” alternatives:
contact lenses
C. Seamless and rapid
59
i. new antibiotics or antibiotic delivery
ii. diagnosing and treating capsular instability to prevent dislocations
iii. less invasive, more efficient surgery will
naturally reduce vitreoretinal complications
iv. preventing cystoid macular edema
E. The future and the legacy
1. Attention to making experience better, not just
outcome
1. Trust and cost: Will be taken care of if we can
provide the above.
2. Improving availability: minimizing preop
workup, planning, back logs
2. Remember the patient: Be kind, be honest, be
ethical, give back.
3. Improving surgeries: efficiency, length, comfort
3. Don’t become complacent; continue to improve.
4. Improving healing: methods for quicker healing,
easier follow-up (or ideally none!)
5. Ideal: lunch-time surgery, patient back to work
same day, no time off required, instant recovery
4. The next generation: teaching, leaving a good
“environment of ophthalmology” for those who
follow
D. Predictable and safe
1. How do we hit plano?
a. Better preop diagnostics
b. Increasing use of intraop diagnostics and customized treatments
c. Improving surgical accuracy (femto-phaco)
d. Better lens algorithms vs. adjustable lenses
e. Ability to manage postop corrections if
needed
2. How do we maintain plano vision?
a. Controlling corneal healing for corneal procedures, and role of corneal crosslinking
Selected Readings
1. Lichtinger A, Rootman DS. Intraocular lenses for presbyopia correction: past, present, and future. Curr Opin Ophthalmol. 2012;
23(1):40-46.
2. Kullman G, Pineda R 2nd. Alternative applications of the femtosecond laser in ophthalmology. Semin Ophthalmol. 2010; 25(56):256-264.
3. Macsai MS, Fontes BM. Refractive enhancement following presbyopia-correcting intraocular lens implantation. Curr Opin Ophthalmol. 2008; 19(1):18-21.
4. Talley-Rostov A. Patient-centered care and refractive cataract surgery. Curr Opin Ophthalmol. 2008; 19(1):5-9.
5. Buznego C, Trattler WB. Presbyopia-correcting intraocular lenses.
Curr Opin Ophthalmol. 2009; 20(1):13-18.
6. Howden LM, Meyer JA. Age and sex composition 2010. 2010
Census Briefs, issued May 2011. Accessed on August 2, 2012 on
http://2010.census.gov/2010census/.
60
Section IV: Presbyopia
Corneal Intrastromal Femtosecond Laser Treatment
for Presbyopia
Mike P Holzer MD
Finding an optimal solution for treating presbyopic patients
remains the Holy Grail in the field of ophthalmology, and a corneal intrastromal femtosecond laser treatment represents one of
the relatively new approaches to treating this condition.
Known as Intracor, the intrastromal approach to presbyopia
uses a femtosecond laser (Victus Femtosecond Laser Platform;
Bausch + Lomb/TPV) to make 5 concentric rings within the
stroma. As there are no incisions in the epithelium or Bowman
membrane, it is a minimally invasive technique. The procedure
takes between 15 and 20 seconds, starting in the center with a
ring diameter of 1.8 mm, with subsequent rings moving toward
the periphery. As the laser uses a proprietary curved patient
interface, it conforms to the natural shape of the cornea, without
applanating the cornea. The formation of these rings produces
a localized biomechanical change that reshapes the cornea to
treat the presbyopia. The procedure is normally only performed
in the nondominant eye. Immediately following the procedure,
the expanded intrastromal rings are clearly visible with slitlamp
examination owing to the cavitation gas from the photodisruption. After a few hours, these gas bubbles disappear and within a
few weeks, the rings are barely visible.
The first Intracor procedures were performed in patients in
2007 by Dr. Luis Ruiz, Bogotá, Colombia.1 A subsequent prospective, multicenter study was conducted in Germany for CE
Mark approval for the treatment of presbyopic hyperopes.2 In
this study, 63 presbyopic patients with mild hyperopia underwent the Intracor procedure in the nondominant eye. Mean
patient age was 54 years, and all patients required a near addition of at least +2 D. Distance refraction was +0.5 D to +1.25 D,
with a maximum cylinder of +0.5 D and spherical equivalent
(SE) of +0.25 D to +1.0 D. Preoperative SE, sphere, and cylinder
were +0.63 D, +0.75 D and -0.25 D, respectively. All patients
had a corrected distance visual acuity (CDVA) of 20/25 or better
and a corneal thickness of ≥ 500 μm.
One-year data on 58 patients found refraction remained
relatively stable after surgery during the postoperative follow-up
period, with SE, sphere, and cylinder values of 0.0 D, 0.25 D,
and 0.0 D, respectively. The treatment was found to induce
a myopic shift of -0.5 D, which occurred in the first 1 month
after surgery, but then stabilized up to 1 year postoperatively.
At 1 year postop, the mean uncorrected distance visual acuity
(UDVA) was unchanged from the preoperative value of 0.1 logMAR, with 43.1% of patients gaining 1 or more lines; 24.1%
were unchanged and 32.7% losing 1 line or more. For CDVA,
the mean value remained unchanged at 0.0 logMAR postoperatively, compared with the same preoperative value. 46.5% of
patients had no change in CDVA, whilst 25% gained 1 or more
lines and 28.5% lost 1 or more lines. A significant improvement
in mean uncorrected near visual acuity (UNVA) was observed,
improving from 0.7 logMAR preoperatively to 0.2 logMAR at
1 year postoperatively, with results remaining stable during the
postoperative follow-up period. Patients gained a mean of 4 lines
of UNVA. All procedures were uneventful.
Further long-term subgroup analysis on 25 patients from the
single Heidelberg site found the results remain stable over time.
At 18 months follow-up, the UNVA was 0.2 logMAR compared
with 0.7 logMAR preoperatively, with a median gain of 5 lines
of near vision.3 Corneal steepening also remained stable during
the 18-month follow-up period. In addition, no significant loss
of endothelial cell density or corneal thinning was observed. The
stability of the outcomes in this subgroup was also reported at 36
months follow-up with UNVA of 0.16 ± 0.19 logMAR (20/30).4
Mean UDVA was 0.15 ± 0.09 logMAR (20/28) compared with
0.11 ± 0.11 logMAR (20/25) preoperatively.
A study to determine IOL power calculations for patients
previously treated with Intracor who subsequently develop a
cataract indicate that normal IOL power calculations can be
used.5 A case study report on an Intracor patient who developed
a cataract 8 months after the Intracor procedure found the standard approach to calculating the IOL lens power with optical
biometry data and the Holladay I formula provided a predictable
outcome.6 The effect of the Intracor procedure remained stable
following the cataract surgery, with a slight improvement in near
vision from 20/40 post-Intracor treatment to 20/25 six months
post-cataract surgery.
In summary, the treatment of presbyopia using a corneal
intrastromal procedure provides a good solution for presbyopic
hyperopes (+0.5 D to +1.25 D), where patients normally gain
4-5 lines of near vision with a potential slight impact on distance
vision and few side effects. Stable refractive outcomes have been
observed over a 3-year follow-up period, with no regression or
weakening of the cornea observed to date. As with all presbyopic
procedures, this procedure requires careful patient selection,
and patients should be advised of the myopic shift and possible
minor photopic phenomena in dim lighting.1 However, with the
correct patient selection and management, the procedure has the
advantage of being a minimally invasive procedure that is quick
to perform, with a fast recovery time.
References
1. Ruiz LA, Cepeda LM, Fuentes VC. Intrastromal correction of
presbyopia using a femtosecond laser system. J Refract Surg. 2009;
25(10):847-854.
2. Holzer MP, Knorz MC, Tomalla M, Neuhann TM, Auffarth GU.
Intrastromal femtosecond laser presbyopia correction: 1-year
results of a multicentre study. J Refract Surg. 2012; 28(3): 182-188.
3. Menassa N, Fitting A, Auffarth GU, Holzer MP. Visual outcomes
and corneal changes after intrastromal femtosecond laser correction
of presbyopia. J Cataract Refract Surg. 2012; 38:765-773.
4. Holzer MP, Sanchez MJ, Thomas BC, Limberger I, Rabsilber TM,
Auffarth GU. Long-term effectiveness and stability of intrastromal
femtosecond laser treatments. Free paper. American Society of
Cataract and Refractive Surgery; April 22, 2012; Chicago, Ill.
5. Rabsilber TM, Haigis W, Auffarth GU, Mannsfeld A, Ehmer A,
Holzer MP. Intraocular lens power calculation after intrastromal
femtosecond laser treatment for presbyopia: theoretic approach. J
Cataract Refract Surg. 2011; 37(3): 532-537.
6. Fitting A, Rabsilber TM, Auffarth GU, Holzer MP. Cataract surgery after previous femtosecond laser intrastromal presbyopia treatment. J Cataract Refract Surg. 2012; 38(7):1293-1297.
61
Corneal Excimer Laser Ablations
I.Monovision
A. Definitions and optical effects
1. Correcting presbyopia with one eye focused for
distance and the other for near – myopic eye
(-1.25 to -2.50 D)
2. Familiar with laser vision correction; disappointed with current options; monovision not
acceptable to many.
3. Patients not ready for IOLs.
2. Mini-monovision: correction for intermediate
range (-0.50 to -0.75 D)
4. Over 10 years of experience; good results and
patient satisfaction.
3. Micro-monovision or blended vision: increased
range of binocular vision from distance to near
usually from multifocality; adjust spherical aberration (SA) in both distance and near eye1-3
5. Bilateral treatment or monocular in nondominant eye (blended vision or advanced monovision)
4. Vision is corrected for only 1 focal point; works
for myopes and hyperopes
6. Micro-monovision: distance and near eyes with
residual SA to ↑ depth of field
5. Small impact on stereopsis, contrast sensitivity
(CS) and binocular visual acuity (VA)
7. Off-label use increasing; frustration, no FDA
approval
6. Does not add additional aberrations to the cornea for future surgery – multifocal IOLs
7. High satisfaction rate – if proper selection4
8.Reversible
B. Patient selection for monovision
1. Best accepted in optimistic, adaptable people
with casual and intermittent near visual demands
2. Not well accepted in people who need precise,
binocular, close-range vision or stereopsis or precise, binocular, distance vision
3. Avoid people who cannot understand the tradeoffs and compromises.
1. Patient selection critical
a. Realistic expectation: may require glasses,
distance or near
b. Distance acuity must be good O.U.
B. How does presbyLASIK work?
1. Lasers can create an aspheric shape; smooth
transition; enhances near vision.
2. Induce negative or positive SA to ↑ depth of field
(pseudoaccommodation)7
3. More near vision; more compromise of distance
and optical quality
4. Higher corrections, more near effect.
5. Vertical coma and other aberrations can hinder near performance and patient satisfaction
(decentered ablations).
C. Monovision pearls
2. Ideal correction: -1.50 D
72%-96%5,6
C. Advantages of presbyLASIK
1. Young presbyopes: -4 to +4 D custom ablation
2. Retain existing accommodation and clear lens
3. Uses proven LV technology, no increased risk
from surgery, low cost
4. Can enhance or remove the correction in most
cases
5. Can be performed bilaterally
6. Causes few undesirable optical effects
3. Patient satisfaction:
4. Enhancement of distance eye more frequent:
~20%
7. Vision at 6 months in most series: distance 20/20
to 20/30; near J1 to J3
5. May be combined with adjustment of SA (< 0.40
µm) to enhance depth of field and create a blend
zone
8. PresbyLASIK can improve near vision in monofocal pseudophakes.
6. Contact lens trial, although not perfect, always
good if patient is unsure of monovision
II. Multifocal LASIK, Aspheric LASIK, or PresbyLASIK
1. Baby boomers want to get rid of glasses.
A. Why the increased interest in presbyLASIK?
D. Disadvantages of presbyLASIK
1. Multiple approaches: center near vs. center far
vs. micro-monovision
2. Limited effect: Choose patients wisely; patient
often would like stronger add.
62
3. Some loss of “quality of vision” trade off, some
loss of CDVA or CNVA. It is a compromise.
4. More enhancements needed; up to 30% improve
distance or near vision
5. Near vision dependent on pupil size
6. Not permanent: refraction, lens, accommodation
change with age
7. Changes the corneal shape: induces aberrations.
This may be a problem for future cataract surgery with multifocal IOLs.
8. Ocular surface problems will affect patient’s
vision and satisfaction.
E. PresbyLASIK
1. Inferior off centered11
2. Center near: aspheric profile for distance and
near, central 3 mm more prolate12-14
3. Peripheral near15-18
d. 60 eyes of 30 patients; range: -3.88 to
+2.63.5 D of SE and up to 1.5 D of cylinder12
i. At 6 months, 83% had distance VA of
20/25 and 83% could read newspaper
print without glasses. 80% of hyperopes,
90% of emmetropes, and 80% of myopes
achieved J2 UNVA.
ii. Line loss of 1 line: 40% for hyperopes and
emmetropes, while 10% of myopes lost
3 lines. Contrast acuity decreased in all
groups monocularly.
iii. Hyperopes most satisfied. Myopes still
required glasses for near. Near effect not
fully reached.
techniques8-10
a. More neuroadaption required; may take 6
months for stabilization of final distance
vision
b. Easier to perform; double card with current
lasers; myopic and hyperopic treatments
c. Longer treatments, more tissue removed
d. Enhancements 2%-30%
3. Mel 80 Carl Zeiss Meditec System
a. Laser blended vision, expanded depth of
focus
b. Developed by Reinstein,1,2 incorporated in
CRS-Master
c. Combines nonlinear aspheric ablation profiles
with micro-monovision
d. Can treat myopes, hyperopes, and emmetropes (+5.75 to -9.00 D)
e. Profile optimizes induction of SA for each
patient while avoiding excessive SA to prevent
visual disturbances or loss of CS (neg SA for
hyperopes and emmetropes, positive SA for
myopes).
F. Current status of presbyLASIK
1. AMO Visx System
a. Center near, hyperopic treatments: Not available in North America
f. Dominant eye plano with nondominant eye
-1.50 D with adjusted SA
b. 100% 20/25 and J3 at 1 year: Jackson (mean
SE 1.97 D)13
g. 94% myopes, 80% hyperopes, and 92%
emmetropes see 20/25 and J23
c. 64% 20/25 and J3 at 6 months: Jung (mean
SE 1.16 D)14
h. No change or improvement in CS
d. Assil used photopic pupillometry to treat
hyperopes for presbyopia in the nondominant
eye.19
i. Blurred nondominant eye added for binocular
distance vision. The vision improved from
92% monocularly to 96% binocularly 20/20.
e. Tamayo and Epstein developed algorithms
for peripheral near treatments for myopia,
emmetropia and hyperopia.20
4. Technolas Perfect Vision (TPV) System
a. Supracor – an “Intracor for Excimer”
b. New presbyopic algorithm for myopic, hyperopic, and emmetropic eyes as well as postLASIK cases
c. Performed using the Technolas Excimer
Workstation 217P
d. Central near approach
e. Chaubard conducted a multicenter trial with
46 eyes of 23 presbyopic hyperopic patients.22
2. Schwind Amaris System
a. PresbyMAX and PresbyMAX µ-monovision
software developed by Alió.8,12,21
b. Bi-aspheric central presbyLASIK ablation
profile with a minimum of aberrations at the
near and distance foci can correct myopia,
hyperopia, and astigmatism with additions
between +0.75 and +2.50 D.
c. PresbyMAX plans -0.5 D refractive outcome
O.U. while µ-monovision assigns -0.125 D
for dominant eye and -0.875 D for the nondominant eye.
i. Bilateral treatments with 6.0 optical zone
aiming for slight myopic
ii. Preop SE +1.67 at 6 months -0.41 D
iii. 87% 20/25 and J2, 2 eyes losing 1 line of
CDVA at 6 months
a. EC-5000 CXIII laser, distance-dominant central cornea algorithm called pseudoaccommodative cornea (PAC) for treatment of myopic,
hyperopic, and emmetropic presbyopia9,15,23
b. Inclusion of the OPA (Optimized Prolate
Ablation) software
c. 195 eyes treated by Uy assessed out to 3
months.17
6. Retreatment rate 20%-30%. Some patients are
not content to compromise distance vision for
near.
7. Some loss of “quality of vision” trade off
8. Management of the ocular surface is key to best
results.
9. Blended vision with increased depth of field in
both eyes is a good option.
ii. At 3 months SE was -0.40 for myopes and
+0.15 D for hyperopes and emmetropes.
iii. 20/30 UDVA and J3 achieved in 83% of
myopes and 87% of hyperopes and emmetropes.
3. Reinstein DZ, Archer TJ, Gobbe M. Aspheric ablation profile for
presbyopic corneal treatment using the MEL80 and CRS-Master
laser blended vision module. J Emmetropia. 2011; 2:161-175.
iv. All corneas became increasingly steeper
from center to periphery with induction
of positive SA of 0.312 μm in myopes and
0.016 in hyperopes.
4. Miranda D, Krueger RR. Monovision laser in situ keratomileusis
for pre-presbyopic and presbyopic patients. J Refract Surg. 2004;
20:325-328.
v. Retreatment rate less than 2%
a. Allegretto Eye-Q F-CAT profile
b. Off-label use in the United States. Myopic
treatment at 5.5-mm optical zone followed by
a 6.0-mm optical zone hyperopic correction;
overcorrects by 1.00 to 2.25 and then plano
with the second ablation.24,25
1. Reinstein DZ, Archer TJ, Gobbe M. LASIK for myopic astigmatism
and presbyopia using non-linear aspheric micro-monovision with
the Carl Zeiss Meditec MEL80 platform. J Refract Surg. 2011;
27:23-37.
i. Preop SE was -3.80 D for myopes and
+1.00 for hyperopic or emmetropic presbyopes.
6. WaveLight System
References
c. Range -5.00 to +3.00 D with up to 3.00 D
of cylinder; in 500 patients UDBVA 20/25
in 95% and UNBVA J3 in 95%. No loss of
CDVA, enhancements 8%-10%.
d. Nondominant eye can be targeted with more
negative Q-value and myopic defocus.
G. PresbyLASIK: Conclusion
1. PresbyLASIK continues to show promise for correcting young presbyopes.
2. More high-quality scientific evidence is needed.
Most studies report short-term results.
3. Custom algorithms are being used in centers
worldwide; it is difficult to compare results.
4. All laser manufacturers are developing software
for either central or peripheral presbyLASIK creating either negative SA for central or positive SA
for peripheral near.
5. Nidek System
iv. Good patient satisfaction, most required
no glasses
63
5. Limited effect as presbyopia increases with age
as well as changes in the crystalline lens; choose
patients wisely.
2. Reinstein DZ, Couch DG, Archer TJ. LASIK for hyperopic astigmatism and presbyopia using micro-monovision with the Carl Zeiss
Meditec MEL80 platform. J Refract Surg. 2009; 25:37-58.
5. Garcia-Gonzalez M, Teus MA, Hernandez-Verdejo JL. Visual
outcomes of LASIK-induced monovision in myopic patients with
presbyopia. Am J Ophthalmol. 2010; 150:381-386.
6. Braun EH, Lee J, Steinert RF. Monovision in LASIK. Ophthalmology. 2008; 115:1196-1202.
7. Rocha KM, Vabre L, Chateau N, Krueger RR. Expanding depth of
focus by modifying higher-order aberrations induced by an adaptive optics visual simulator. J Cataract Refract Surg. 2009; 35:18851892.
8. Alió JL, Amparo F, Ortiz D, Moreno L. Corneal multifocality with
excimer laser for presbyopia correction. Curr Opin Ophthalmol.
2009; 20:264-271.
9. Alarcon A, Anera RG, del Barco LJ, Jimenez JR. Designing multifocal corneal models to correct presbyopia by laser ablation. J
Biomedl Optics. 2012; 17:018001.
10. Koller T, Seiler T. Four corneal presbyopia corrections: simulations
of optical consequences on retinal image quality. J Cataract Refract
Surg. 2006; 32:2118-2123.
11. Bauerberg JM. Centered vs. inferior off-center ablation to correct
hyperopia and presbyopia. J Refract Surg. 1999; 15:66-69.
12. Uthoff D, Polzl M, Hepper D, Holland D. A new method of cornea
modulation with excimer laser for simultaneous correction of presbyopia and ametropia. Graefes Arch Clin Exp Ophthalmol. Epub
ahead of print 22 Feb 2012.
13. Jackson WB, Tuan KM, Mintsioulis G. Aspheric wavefront-guided
lasik to treat hyperopic presbyopia: 12-month results with the Visx
platform. J Refract Surg. 2011; 27:519-529.
14. Jung SW, Kim MJ, Park SH, Joo CK. Multifocal corneal ablation
for hyperopic presbyopes. J Refract Surg. 2008; 24:903-910.
15. El Danasoury AM, Gamaly TO, Hantera M. Multizone LASIK
with peripheral near zone for correction of presbyopia in myopic
and hyperopic eyes: 1-year results. J Refract Surg. 2009; 25:296305.
64
16. Telandro A. The pseudoaccommodative cornea multifocal ablation with a center-distance pattern: a review. J Refract Surg. 2009;
25:S156-159.
17. Uy E, Go R. Pseudoaccommodative cornea treatment using the
Nidek EC-5000 CXIII excimer laser in myopic and hyperopic presbyopes. J Refract Surg. 2009; 25:S148-155.
18. Pinelli R, Ortiz D, Simonetto A, Bacchi C, Sala E, Alio JL. Correction of presbyopia in hyperopia with a center-distance, paracentralnear technique using the Technolas 217z platform. J Refract Surg.
2008; 24:494-500.
19. Assil KK, Chang SH, Bhandarkar SG, Sturm JM, Christian WK.
Photopic pupillometry-guided laser in situ keratomileusis for hyperopic presbyopia. J Cataract Refract Surg. 2008; 34:205-210.
20. Epstein RL, Gurgos MA. Presbyopia treatment by monocular
peripheral presbylasik. J Refract Surg. 2009; 25:516-523.
21. Luger MHA, Ewering T, Arba Mosquera S. 3-month experience in
presbyopic correction with bi-aspheric multifocal central presbylasik treatments for hyperopia and myopia with or without astigmatism. J Optometry. Epub ahead of print 22 Feb 2012.
22. Chaubard JJ, Castanera J, Pietrini D, Roure A. Six month European
study results of excimer-based treatment of presbyopia using the
Technolas excimer workstation. Technolas Perfect Vision White
Paper. 2011.
23. Telandro A. Pseudo-accommodative cornea: a new concept for correction of presbyopia. J Refract Surg. 2004; 20:S714-717.
24. Gordon M. Laser presbyopic corrections with the WaveLight laser.
Cataract and Refractive Surgery Today. 2010: 71-77.
25. Gordon M. Presbyopia corrections with the WaveLight Allegretto:
3-month results. J Refract Surg. 2010; 26:S824-826.
65
Corneal Ablations: What About Reversibility?
Michael C Knorz MD
The correction of presbyopia is frequently called the last frontier
of refractive surgery. As long as no causative treatment, which
would be restoring the flexibility of the crystalline lens, is available, all nonsurgical and surgical approaches are compromises.
A compromise means that the action has benefits but also side
effects. We must therefore always keep in mind that the respective surgical procedure has unwanted side effects, which must be
differentiated from the surgical risks inherent to any procedure.
For example, a reduction in contrast sensitivity or halos at night
due to changes in corneal shape are unwanted side effects of corneal laser surgery, but a bacterial infection resulting in a scar is a
surgical risk of the same procedure.
We must accept surgical risks, but we should be able to
reverse unwanted side effects inherent to our surgical treatment
of presbyopia. Multifocal corneal ablations have a significant
risk of side effects, as shown in a study by Alio et al.1 Out of
50 eyes of 25 patients treated bilaterally, 20% lost 2 lines of
best-corrected distance visual acuity, 51% lost 2 lines of bestcorrected near visual acuity, and image quality, measured by
point spread function (PSF), decreased from 37.6 preoperatively
to 28.4 postoperatively.1 Intrastromal femtosecond laser treatment to steepen the central cornea (Intracor procedure) also had
significant side effects as shown in a study by Holzer et al.2 Of 63
eyes treated with 12 months follow-up, 7.1% lost 2 or more lines
of best-corrected distance visual acuity, 11.5% lost 2 or more
lines of best-corrected near visual acuity, 19.6% were not satisfied with the result, 12.3% would not have the procedure again,
and 16% would not recommend the procedure.2
These two studies clearly indicate that corneal ablations to
correct presbyopia cause significant problems in many patients.
Reversibility of these procedures has not been demonstrated so
far. These procedures should therefore be used with extreme caution, as the unwanted side effects may not be reversible.
References
1. Alio JL, Chaubard JJ, Calz A, Sala E, Patel S. Correction of presbyopia by Technovision central multifocal LASIK (PresbyLASIK). J
Refract Surg. 2006; 22:453-460.
2. Holzer MP, Knorz MC, Tomalla M, Neuhann T. Intrastromal femtosecond laser presbyopia correction: 1-year results of a multicenter
study. J Refract Surg. 2012; 28:182-188.
66
Corneal Inlays
N o tes
Simultaneous LASIK and Implantation of an
Intracorneal Inlay
Introduction
Several publications have reported that implantation of a smallaperture corneal inlay (Kamra from AcuFocus, CA) under a
corneal lamellar flap or pocket is a safe and effective treatment
for emmetropic presbyopes.1-3 However, most patients are not
emmetropic. In fact, the Beaver Dam Study4 stated that only
11.5% of people between 43 and 84 years of age were actually
emmetropic. Additionally, clinically important refractive errors
(myopia, hyperopia, and/or astigmatism) have been reported to
affect half of the U.S. population.5 East Asian countries seem to
have an even higher prevalence of refractive errors, especially
myopia, as reported in a study on the Chinese residing in Singapore; the prevalence of myopia was 1.5 to 2.5 times higher than
similarly aged European-derived populations in the United States
and Australia.6 In Japan, a recent study performed in a series of
patients over 40 years of age reported that 41.8% are myopic,
27.9% are hyperopic, 54% have astigmatism, and 8.2% have
high myopia with a spherical equivalent (SE) of <-5.0 D.7 By
comparison, the prevalence of myopia and high myopia in Japan
is higher than in Western and other Asian countries.
While neither treating these patients with LASIK or an inlay
alone will resolve their vision complaints, a combination surgical procedure has evolved to address these issues. By pairing a
LASIK procedure with subsequent inlay implantation, surgeons
are able to correct a patient’s refractive error first and then treat
their presbyopia. This new procedure, often referred to as SimLASIK, is proving to be an effective treatment option.8
Figure 2. Characteristics of the inlay.
Figure 3. Principle of the inlay.
Figure 1. Purpose.
67
68
Figure 7. Uncorrected near visual acuity.
Figure 4. Subject and methods.
Figure 8. Patient satisfaction.
Figure 5. Inclusion criteria.
Results
1175 patients were available at the 1-year postoperative exam,
mean uncorrected distance visual acuity (VA) improved 8 lines,
from preoperative 20/125 to 20/20, with 72% of patients achieving 20/20 or better uncorrected distance VA. Mean uncorrected
near VA improved 3 lines, from preoperative J6 to J2 at 1 year,
with 56% of patients achieving J1 or better and 77% achieving
J2 or better. Mean corrected distance VA and corrected near VA
did not have any change.
At 1 year, 92% of the patients are satisfied with their vision
without reading glasses and only 8% reported needing reading
glasses for any period of time (always:4%, often:1%, sometimes:
3%).
Discussion
Figure 6. Uncorrected distance visual acuity.
When working the inlay it is important to carefully assess your
patients to ensure they are good candidates clinically as well as to
ensure that their expectations for their postoperative results are
realistic.
Careful analysis of results to date indicate that the top factors affecting a successful result are achieving your target postop
refraction, careful ocular surface management, and ensuring
your corneal dissection is smooth. Inlay centration is also important; however, placement is more forgiving than first expected.
During the surgical procedure it is important to minimize
manipulation of the cornea to speed recovery. Additionally, proactive management of the healing process through steroids and
ocular surface quality with tears and punctal plugs is necessary.
Ultimately, the inlay is removable. So in the event that the
patient would like to pursue another treatment option, the inlay
does not limit the patient or surgeon from future vision correction procedures.
Conclusion
In this high-volume study of simultaneous LASIK surgery and
inlay implantation, 1-year outcomes demonstrate improvements
in both distance and near visual acuity, high patient satisfaction, and reduced dependence on reading glasses. With a good
technique and careful management, this surgical procedure for
presbyopic patients with refractive errors is an effective treatment option.
69
References
1. Yilmaz OF, Alagoz N, Pekel G, Azman E, Aksoy EF, Cakir H, Bozkurt E, Demirok A. Intracorneal inlay to correct presbyopia: longterm results. J Cataract Refract Surg. 2011; 37:1275-1281.
2. Seyeddain O, Hohensinn M, Riha W, et al. Small-aperture corneal
inlay for the correction of presbyopia: 3-year follow-up. J Cataract
Refract Surg. 2012; 38(1):35-45.
3. Waring GO IV. Correction of presbyopia with a small aperture corneal inlay. J Refract Surg. 2011; 27(11):842-845.
4. Wang Q, Klein BE, Klein R, Moss SE. Refractive status in the Beaver Dam Eye Study. Invest Ophthalmol Vis Sci. 1994; 35(13):43444347.
5. Vitale S, Ellwein L, Cotch MF, Ferris FL III, Sperduto R. Prevalence
of refractive error in the United States, 1999-2004. Arch Ophthalmol. 2008; 126(8):1111-1119.
6. Wong TY, Foster PJ, Hee J, et al. Prevalence and risk factors for
refractive errors in adult Chinese in Singapore. Invest Ophthalmol
Vis Sci. 2000; 41(9):2486-2494.
7. Sawada A, Tomidokoro A, Araie M, Iwase A, Yamamoto T; Tajimi
Study Group. Refractive errors in an elderly Japanese population:
the Tajimi study. Ophthalmology 2008; 115(2):363-370.e3.
8. Tomita M, Kanamori T, Waring GO IV, et al. Simultaneous corneal inlay implantation and laser in situ keratomileusis for presbyopia in patients with hyperopia, myopia, or emmetropia: six-month
results. J Cataract Refract Surg. 2012; 38(3):495-506.
70
Multifocal IOLs
Jorge Alió MD PhD, Felipe Soria MD
I.Definition
A.Accommodation
B.Pseudoaccommodation
C. Multifocal IOLs (MIOLs)
II.History1,2
A. Refractive lenses
1. First multifocal lens to be granted by the FDA:
Bulls Eye Lens
a. Array (Advance Medical Optics; Santa Ana,
Calif., USA)
i. ReZoom (approved 2005; Advance Medical Optics, acquired by Abbot)
B. Diffractive lenses
1. Pharmacia 811E (Advance Medical Optics;
Santa Ana, Calif., USA)
2. 3M 815LE (3M Corp; St. Paul, Minn., USA)
3. ReSTOR (Alcon; Fort Worth, Texas, USA)
a. First diffractive IOL to be FDA approved, in
2005
b. FDA approved aspheric version of the
ReSTOR (AcrySof IQ, ReSTOR) in 2007.
III. MIOL Optics
A. Type of optics
1.Refractive
a.ReZoom
b. M-Flex 680F, 630F
4. Ghost vision
D. Posterior capsule opacification
E. Decreased contrast sensitivity (variable)
V. Guidelines to Follow
A. Focus dominant for far vision
B. Adequate disparity between near and far foci
C. Aspheric design
D. Available toric model. Regular astigmatism should
be corrected with toric MIOL models.
E. Pupil independent mechanism
F. Good optical performance on the optical bench and
“in vivo”
G. Good capsular stability
H. Low rate of posterior capsular opacification
I. Implantable through a sub-2-mm incision
J. Demonstration of good visual outcomes for intermediate and near vision that can be adapted to the
lifestyle of the patient
VI. MIOLs Commercially Available (see Table 1)
VII. Clinical Results of MIOLs (see Table 2)
A.Refractive
1.ReZoom
a.Vision
i. Dependent on spectacles for near tasks;
intermediate vision is spectacle independent.3
ii. Distant visual performance was excellent under photopic conditions, but was
reduced under mesopic levels.4
iii. Mixing and matching multifocal IOLs
in selected cataract patients provides an
excellent visual outcome, a high level of
patient satisfaction, and spectacle-free
visual function. A period of neuroadaptation lasting at least 6 months is necessary
to obtain better visual function results.5
2.Diffractive
a. Tecnis ZMB00
3.Diffractive-refractive
a. AcrySof ReSTOR SN6AD1/SN6AD3
b. AT.LISA 366D
4.Segmental
C. Surgically induced astigmatism if incision is longer
than 2 mm
3. Night vision problems
2. First presbyopia-correcting IOL to be FDA
approved in 1997
a. Lentis MPlus
IV. MIOL Complications
A. Decentration / tilt
B. Photopic phenomena
1.Glare
2.Halos
b. Reading performance: Multifocal IOLs with a
diffractive component provided a comparable
reading performance that was significantly
better than the one obtained with refractive
multifocal and monofocal IOLs.6
71
Table 1. Some Models of Modern MIOLs Commercially Available
AT-LISA 809M (Zeiss)
Incision Size
Asphericity
Near Add
Pupil % of Light N/F
1.8 mm
Neutral
+3.75
Independent
35/65
Fine Vision (PhysIOL)
1.8 mm
Neutral
+3.5/trifocal + 1,75
Dependent
35/17/48
ReSTOR (Alcon)
2.2 mm
Neutral
+4/+3
Dependent
50/50
Seelens MF (Hanita)
1.8 mm
Aspheric Biconvex
+3
Independent
50/50
Tecnis One (AMO)
2.75 mm
Aspheric
+4
50/50
Increased DOF
Mplus (Oculentis)
2 mm
Neutral
+3/1´5
Independent
80/20
Rayner M-flex
2.75 mm
Aspheric
+4/+3
Not defined
Table 2. Intraocular Optical Quality and Summary of Clinical Outcomes of MIOLs
Intraocular Optical Quality
Constrast Sensitivity
Worst Outcome
Night Vision
Acrilisa
+++
Decreased
Intermediate vision
Halos, glare
Fine Vision
++
Moderately decreased
All distances good?
Halos
ReSTOR
++++
Decreased
Near vision limited
Halos, glare
Tecnis One
+++
Decreased
Intermediate vision
Halos+++
Mplus +3
+++ (plate haptic)
Not significantly affected
All distances good
Sectorial halo
Mplus +1.5
+++ (plate haptic)
Not affected
Near vision
Sectorial halo
intermediate visual acuity is better with the
Lentis Mplus LS-312 IOL.9
c. Photic phenomena: Photic phenomena were
present in all IOLs, albeit more frequently in
ReZoom IOLs.3
b. Reading performance: ReSTOR SN6AD3 has
significantly better uncorrected reading acuity than monofocals and refractive multifocal
IOLs.10
c. Photic phenomena: Patients with ReSTOR
SN6AD3 can perform several daily tasks at
near and intermediate distances, with more
night-driving limitation than with a full diffractive IOL.11
d. Contrast sensitivity is better with the
ReSTOR SN6AD3 at 12 cycles per degree
(cpd) and 18 cpd under photopic conditions
than with the Lentis Mplus LS-312. No significant differences were found under mesopic
conditions.12
B. Diffractive: Tecnis ZMB00
1. Vision: At 60 days, 94.3% of eyes could read
1.00 close-up without correction.7
2. Photic phenomena: Patient satisfaction in terms
of dysphotopsia effects and visual acuity was
excellent.7
C.Diffractive-refractive
1. AcrySof ReSTOR SN6AD1/SN6AD3
a.Vision
i. The ReSTOR +3.00-D add has performed
better than the ReSTOR +4.00-D add at
all intermediate distances studied, with
similar performance for distance and near
visual acuity, contrast sensitivity, and
quality of life.8
ii. Uncorrected near visual acuity and distance corrected near visual acuity is better
with the ReSTOR SN6AD3 than with
the Lentis Mplus LS-312 IOL, whereas
2. Acri.LISA 366D
a.Vision
i. Acri.LISA 366D has significantly better
uncorrected reading acuity than the monofocal and refractive multifocal IOLs at 1
month and 6 months postoperatively.10
72
ii. Significantly better values of uncorrected
near visual acuity and corrected distance
near and intermediate visual acuity are
found in Acri.LISA vs. Lentis Mplus
LS-312.13,14
b. Contrast sensitivity
i. Contrast sensitivity improves significantly
at all spatial frequencies under photopic
and scotopic conditions after surgery.13
ii. Significantly better values are observed in
photopic contrast sensitivity for high spatial frequencies in Lentis Mplus LS-312 vs.
Acri.LISA.14
i. The quality-of-life index related to reading
ability improves significantly at 3 months.
Implantation of the multifocal diffractive
IOL significantly improved reading performance, which had a positive effect on the
patient’s quality of life postoperatively.13
i. There are no significant differences in contrast sensitivity between the Lentis Mplus
vs. Acri.Smart 48S monofocal IOL.21
ii. The Crystalens HD has better contrast
sensitivity under photopic conditions at all
spatial frequencies than Lentis MPlus.17
iii. Photopic contrast sensitivity is significantly better with Lentis MPlus IOL than
with the ReSTOR SN6AD3 IOL.19
iv. Significantly better values were observed
in photopic contrast sensitivity for high
spatial frequencies in the Lentis MPlus vs.
Acri.Lisa 366D.20
ii. Provides a comparable reading performance that is significantly better than the
one obtained with refractive multifocal
and monofocal IOLs.10
c. Photic phenomena
i. Moderate halos, glare, and night-vision
problems are reported by 6.2%, 12.5%,
and 15.6% of patients, respectively.21
VIII. Intraocular Optical Quality (see Table 2)
IX. Election of the Best MIOL for Each Patient
A. Major criteria
1. Visual potential
2. Altered contrast sensibility
1. Lentis MPlus
3. Advanced senility
a.Vision
4. Altered diopter quality of the cornea (not in
aberrated corneas)
5. Comorbidities (amblyopia, glaucoma and macular disease)
D.Segmental
b. Contrast sensitivity
c. Quality of life
i. Lentis MPlus LS-312 MF30 IOL has statistically significantly better uncorrected
and distance-corrected near visual acuity
than Lentis MPlus LS-312 MF15 IOL.
Instead Lentis MPlus LS-312 MF30 has
significantly better uncorrected intermediate visual acuity at 3 months.15
ii. Provides adequate distance, intermediate,
and, to a lesser extent, near vision with
high rates of spectacle freedom.16
iii. Distance-corrected near visual acuity is
significantly better with the Lentis MPlus
vs. the Crystalens HD.17
iv. Refractive predictability and intermediate
visual outcomes with the Lentis Mplus
LS-312 IOL improved significantly when
implanted in combination with a capsular
tension ring.18
v. Uncorrected near visual acuity and distance corrected near visual acuity are
better with the ReSTOR SN6AD3 IOL
than with Lentis Mplus LS-312 IOL, but
intermediate visual acuity is better with the
Lentis Mplus.19
vi. In the defocus curve, significantly better
visual acuities are present in eyes with the
Lenti Mplus IOL for intermediate vision
levels of defocus vs. Acri.Lisa 366D.20
B. Minor criteria
1. Personality type
2.Profession
X.Conclusions
Modern MIOLs offer an opportunity for selected
patients with cataract and refractive lens exchange to
promote a spectacle independent outcome for far and
near vision performance.
References
1. Dening J. The birth of the premium IOL channel. In: D Chang, ed.
Mastering Refractive IOLs. New Jersey: SLACK Inc.; 2008; 2-4.
2. Lichtinger A, Rootman DS. Intraocular lenses for presbyopia correction: past, present, and future. Curr Opin Ophthalmol. 2012;
23(1):40-46.
3. Gil MA, Varon C, Rosello N, Cardona G, Buil JA. Visual acuity, contrast sensitivity, subjective quality of vision, and quality
of life with 4 different multifocal IOLs. Eur J Ophthalmol. 2011;
22(2):175-187.
4. Muñoz G, Albarrán-Diego C, Cerviño A, Ferrer-Blasco T, GarcíaLázaro S. Visual and optical performance with the ReZoom multifocal intraocular lens. Eur J Ophthalmol. 2012; 22(3):356-362.
5. Lubiński W, Podboraczyńska-Jodko K, Gronkowska-Serafin J, Karczewicz D. Visual outcomes three and six months after implanta-
tion of diffractive and refractive multifocal IOL combinations. Klin
Oczna. 2011; 113(7-9):209-215.
6. Alió JL, Grabner G, Plaza-Puche AB, et al. Postoperative bilateral
reading performance with 4 intraocular lens models: six-month
7. Bautista CP, González DC, Gómez AC. Evolution of visual performance in 70 eyes implanted with the Tecnis(®) ZMB00 multifocal
intraocular lens. Clin Ophthalmol. 2012; 6:403-407.
8. Santhiago MR, Wilson SE, Netto MV, et al. Visual performance
of an apodized diffractive multifocal intraocular lens with +3.00-d
addition: 1-year follow-up. J Refract Surg. 2011; 27(12):899-906.
9. Alió JL, Plaza-Puche AB, Javaloy J, Ayala MJ. Comparison of the
visual and intraocular optical performance of a refractive multifocal
IOL with rotational asymmetry and an apodized diffractive multifocal IOL. J Refract Surg. 2012; 28(2):100-105.
10. Alió JL, Grabner G, Plaza-Puche AB, et al. Postoperative bilateral
reading performance with 4 intraocular lens models: six-month
11. Alió JL, Plaza-Puche AB, Piñero DP, Amparo F, Rodríguez-Prats JL,
Ayala MJ. Quality of life evaluation after implantation of 2 multifocal intraocular lens models and a monofocal model. J Cataract
Refract Surg. 2011; 37(4):638-648.
12. Alfonso JF, Fernández-Vega L, Blázquez JI, Montés-Micó R. Visual
function comparison of 2 aspheric multifocal intraocular lenses. J
13. Alió JL, Plaza-Puche AB, Piñero DP, et al. Optical analysis, reading
performance, and quality-of-life evaluation after implantation of
a diffractive multifocal intraocular lens. J Cataract Refract Surg.
2011; 37(1):27-37.
14. Alio JL, Plaza-Puche AB, Javaloy J, Ayala MJ, Moreno LJ, Piñero
DP. Comparison of a new refractive multifocal intraocular lens
with an inferior segmental near add and a diffractive multifocal
intraocular lens. Ophthalmology 2012; 119(3):555-563.
73
15. Alió JL, Plaza-Puche AB, Piñero DP, Javaloy J, Ayala MJ. Comparative analysis of the clinical outcomes with 2 multifocal intraocular
lens models with rotational asymmetry. J Cataract Refract Surg.
2011; 37(9):1605-1614.
16. Muñoz G, Albarrán-Diego C, Ferrer-Blasco T, Sakla HF, GarcíaLázaro S. Visual function after bilateral implantation of a new
zonal refractive aspheric multifocal intraocular lens. J Cataract
Refract Surg. 2011; 37(11):2043-2052.
17. Alió JL, Plaza-Puche AB, Montalban R, Javaloy J. Visual outcomes
with a single-optic accommodating intraocular lens and a lowaddition-power rotational asymmetric multifocal intraocular lens. J
18. Alió JL, Plaza-Puche AB, Piñero DP. Rotationally asymmetric multifocal IOL implantation with and without capsular tension ring:
refractive and visual outcomes and intraocular optical performance.
J Refract Surg. 2012; 28(4):253-258.
19. Alió JL, Plaza-Puche AB, Javaloy J, Ayala MJ. Comparison of the
visual and intraocular optical performance of a refractive multifocal
IOL with rotational symmetry and an apodized diffractive multifocal IOL. J Refract Surg. 2012; 28(2):100-105.
20. Alio JL, Plaza-Puche AB, Javaloy J, Ayala MJ, Moreno LJ, Piñero
DP. Comparison of a new refractive multifocal intraocular lens
with an inferior segmental near add and a diffractive multifocal
intraocular lens. Ophthalmology 2012; 119(3):555-563.
21. Alió JL, Piñero DP, Plaza-Puche AB, Chan MJ. Visual outcomes
and optical performance of a monofocal intraocular lens and a
new-generation multifocal intraocular lens. J Cataract Refract Surg.
2011; 37(2):241-250.
22. Muñoz G, Albarrán-Diego C, Ferrer-Blasco T, Sakla HF, GarcíaLázaro S. Visual function after bilateral implantation of a new
zonal refractive aspheric multifocal intraocular lens. J Cataract
Refract Surg. 2011; 37(11):2043-2052.
74
Accommodating IOLs
Burkhard Dick MD
N o tes
75
How to Center Corneal Inlays
I. Importance of Centration
Proper inlay placement is the key to achieving good
outcomes.
II. The Challenge
A. How do you identify the optimal placement?
B. How do you reliably place the inlay?
C. How do you know if you placed the inlay where
you want it?
III. Accuracy Perspective
IV. Diagnostic Unit (AcuTarget)
A.Preoperative
1. Performs accurate centration location and planning
2. Registers patient’s unique sclera features for surgical guidance eye tracking functions
VIII. Postoperative Results Interpretation
A. Decentration coordinates are reported in x- and
y-axis.
B. Negative x-axis values indicate nasal decentration.
IX. Intended vs. Achieved
For Purkinje data the Purkinje is the origin {0(x), 0(y)}
and is represented by the blue cross in the presentation slide. Therefore, the inlay center (represented by
the pink cross in the presentation slide) displacement
values are presented in microns using the established +/coordinate system.
X.Summary
A. Accurate centration of small aperture inlays is critical for optimizing postop visual acuity and quality
B. New objective diagnostic and surgical technology
will:
B. Postoperative: Assesses inlay placement vs. first Purkinje and pupil centroid
1. Capture unique ocular features
2. Real-time surgical guidance on optimal inlay
placement
3. Assess accuracy of achieved versus intended
placement
V. Preop Captured Image (see Figure 1)
VI. Postop Image Capture Process
Postop images are captured using infrared light to distinguish the inlay from the pupil.
VII. Postop Captured Image (see Figure 2)
C. Improve inlay placement accuracy
D. Inform on the need for a recentration
E. Reduce need for a postop enhancement
Figure 1.
76
Figure 2.
77
Preliminary Results From a New Aspheric Apodized
Diffractive Multifocal IOL With a +2.5 D Add Power
Presenting Author: Francesco Carones MD
Purpose: To present preliminary clinical results from a newly
developed multifocal IOL with a +2.5 D add power that is
intended to optimize performance at intermediate and far
distances for patients in need of a lens for distant dominant
lifestyles. Methods: The +2.5 D add IOL differs from the +3.0
D add IOL relative to energy distribution, apodized diffractive
zone, and amount of IOL asphericity. The central zone of the
lens was changed from diffractive to refractive. The apodized
diffractive zone for the +2.5 D IOL contains 7 graduated steps
in a 3.4-mm diameter, compared with the +3.0 D IOL that has
9 graduated steps within a 3.6-mm diameter. After cataract or
clear lens extraction, the +2.5 D add IOL was implanted bilaterally in 6 patients, and in the dominant eye of 10 patients who
received a +3.0 D add IOL in the other eye. Results were assessed
over a 3-month follow-up. Results: For all eyes implanted with
the +2.5 D add IOL, BSCVA was never worse than 20/15.
Patients implanted bilaterally with the +2.5 D add IOL reported
with no visual symptoms, had binocular distance uncorrected
visual acuity (BDUVA) 20/15 in all cases, and all but one could
read J2 or better in a distance range 45 to 70 cm. All patients
with the +2.5 D add IOL in the dominant eye could notice a
slightly better quality of vision (not bothering) than in the other
eye, had BDUVA 20/15 in all cases, and could read J2 or better
in a distance range 35 to 70 cm. Conclusion: These preliminary
results assess the safety and the very good quality of vision the
+2.5 D add IOL can provide, without significantly compromising uncorrected near vision. A mixed approach implanting a
near-distance optimized IOL in the nondominant eye seems to
improve performances.
Experience With a Laser for Cataract Surgery
Presenting Author: Burkhard Dick MD
Purpose: To evaluate advantages and limitations of a femtosecond laser for cataract surgery and potential in challenging cases.
Methods: 400 cases of capsulotomy and lens fragmentation were
completed and documented by video in a controlled prospective
study with a laser for cataract surgery. Docking attempts and
suction breaks were noted. Patients were evaluated for comorbidities, free capsulotomy, and complications. Cataracts were
graded with slitlamp using the LOCS III scale. Effective phacoemulsification time (EPT) during lens removal was noted for all
grades of cataract. The liquid optics interface integrated into the
system allowed for IOP measurements before, during, and after
the laser procedure. A Schiotz tonometer placed through the suction ring directly onto the cornea was used. Results: The first 400
eyes included cases of glaucoma, mature cataracts, Fuchs dystrophy, cornea guttata, pseudoexfoliation, intraoperative floppy iris
syndrome, small pupils, post vitrectomy, anticoagulation, and
scars. We show 99% free capsulotomy, minimal conjunctival
alteration, clear cornea, and only 2 complications. All patients
were successfully treated, with no posterior lens dislocation
or retinal detachment. EPT, across all grades of cataract, was
reduced by 96%, with substantial reductions in even the hardest
grades. Upon application of the suction ring, IOP rose by only
10 mmHg. Conclusions: Image guided laser cataract surgery
provides high precision, low EPT, and low IOP. Key product features such as a gentle liquid optics patient interface, precise femtosecond laser, and image guidance improve safety and enable
the treatment of challenging cases with a broad inclusion criteria.
First 1000 Cases of Laser-Assisted Cataract Surgery
Experiences
Presenting Author: Pavel Stodulka MD PhD
Purpose: To share the experience on the world’s first 1000 consecutive cases of laser-assisted cataract surgeries performed by
the Victus laser. Methods: A femtosecond laser (Victus) capsulotomy and nucleus fragmentation was performed. The average
energy of the laser pulse was 7J. The capsulotomy diameter was
set to 4.75 mm. For lens fragmentation a cross pattern with 4
arms and 3 circles was used. The central part of anterior capsule
was removed by phaco aspiration (Stellaris PC, B+L) with a
centripetal force. Lens material fragmented by laser pulses was
removed by phaco handpiece of the same surgical device. Lens
cortex material was removed by biaxial cannulas via side port
incisions. A variety of one-piece hydrophilic acrylic IOLs were
implanted. Results: A complete laser circular capsulotomy was
achieved in all cases. Small tag irregularities of the capsular edge
were noticed in 11% of eyes. Capsulotomy radial tear during the
phacoemulsification part of surgery developed in 0.2% of eyes.
A femtosecond laser fragmentation of the lens was achieved in
all cases. Slight subconjunctival hemorrhage developed in 21%
of eyes. A significant decrease of the pupil size to less than 5 mm
after the laser part of the procedure was noticed in 12% of eyes.
No other laser-specific complication besides decrease of the
pupil size was noticed. Conclusion: A femtosecond laser-assisted
cataract surgery performed by the Victus laser appears safe and
effective.
78
Refractive IOL Outcomes of Femtosecond
Laser Cataract Surgery vs. Conventional
Phacoemulsification
High-resolution Scheimpflug Images Guide:
Phacoemulsification Technique Selection During
Laser-Assisted Cataract Surgery
Presenting Author: Dan B Tran MD
Purpose: To report the comparative refractive outcomes of
femtosecond laser-assisted refractive cataract surgeries with
conventional phacoemulsification. Methods: Retrospective comparative consecutive case series study of 350 eyes in each group
underwent femtosecond laser-assisted refractive cataract surgery
vs. conventional phacoemulsification. The inclusion criteria
included all eyes with postoperative BSCVA of 20/30 or better,
no previous corneal refractive surgery, no other significant ocular
pathologies, and no intraoperative complications. Results: The
1-month postoperative mean absolute spherical equivalent errors
were 0.25 ± 0.22 D for the femtosecond laser group and 0.28 ±
0.21 D for the conventional phacoemulsification group. Eightyone percent of eyes were within ±0.25 D in the femtosecond
laser group vs. 62% in the conventional group. 100% of eyes in
both groups were within ±1.0 D of intended target correction.
Conclusions: Excellent refractive outcomes can be achieved with
both femtosecond laser-assisted refractive cataract surgery and
conventional phacoemulsification techniques. Femtosecond laser
appears to improve the accuracy to target in the ±0.25 D range.
Presenting Author: Harvey S Uy MD
Visual Outcome, Efficacy, Safety, and Surgical
Efficiency of Femtosecond Laser Refractive Lens
Surgery: 45 Cases
Presenting Author: Ahmed Abd El-Twab Abdou MD
Coauthors: Jorge L Alio MD PhD, Jaime Javaloy PhD, Roberto
Fernandez-Buenaga MD, Felipe Soria MD, Pablo Peña Garcia
MS, Ana Guillamon MS
Purpose: To evaluate the safety and efficacy of the corneal incision, capsulorrhexis, and phacofragmentation of femtosecond
laser refractive lens surgery (FLRLS). Method: Prospective clinical study on 45 cataractous eyes operated with FLRLS by only
one surgeon (27 MICS 1.8 mm and 18 minimal incision 2.2
mm phacoemulsification). We assessed the efficacy in the terms
of nuclear fragmentation, visual and refractive outcome, and
higher-order aberration (HOAs; corneal and internal) analysis.
Corneal pachymetry, endothelial cell count, macular thickness, operative incidents, and postoperative complications were
assessed for safety evaluation. Data were recorded for 1 month
of follow-up. Results: Mean age of patients was 68.9 ± 8.7 years;
40% males and 60% females. The means of ultrasound power
and EPT for nucleus = +3, MICS (52% of cases) and 2.2 incision
(67%) are (1.8 ± 0.9%, 14.7 ± 4.9% P < 0.001) and (1.5 ± 0.9,
4.5 ± 2.9 sec. P = 0.002) respectively. The visual efficacy “(PO
UCA / PRE CVA) x100” for MICS is 160.2% and 149% for
the minimal incision and the mean postoperative SE for MICS
is -0.26 and -0.33 for the minimal incision after 1 month. There
is no significant change in the postoperative corneal HOAs, and
the postoperative mean of the internal coma for both is 0.13 µm.
There were no significant changes in the postoperative central
corneal pachymetry, endothelial cell count, and macular volume,
and the postoperative complications were unremarkable. Conclusion: Our FLRLS experience demonstrates that it is safe and
very efficient in nuclear fragmentation, provides an aberration
free incision, and ensures accurate IOL centration with excellent
visual and refractive outcomes.
Coauthor: Ronald R Krueger MD
Purpose: To determine effectiveness of phacoemulsification (PE)
technique selection based on high-resolution Scheimpflug images
(HRSI) acquired during laser refractive cataract surgery (LRCS).
Methods: Forty-eight eyes underwent LRCS using a femtosecond laser with a HRSI system while 55 control eyes underwent
conventional PE. HRSI images of cataract anatomy guided the
surgeon in selecting a nuclear disassembly technique and PE
machine settings. Main outcome measures: Success of LRCS and
adverse events (AE). Results: All LRCS eyes underwent successful
laser capsulotomy and IOL implantation. No AE were observed
in the LRCS group, while 1 case each of a radial tear and posterior capsule tear developed in the control group. Conclusion:
HRSI may guide selection of surgical technique during PE.
Initial Outcomes of Intrastromal Femtosecond
Arcuate Incisions
Presenting Author: Steven C Schallhorn MD
Coauthor: Jan A Venter MD
Purpose: To analyze 3-month outcomes of femtosecond astigmatic keratotomy. Methods: 113 consecutive eyes underwent
intrastromal arcuate incisions to correct astigmatism using a
150-KHz femtosecond laser. The average patient age was 58.0
years (range: 44 to 69), and 62% were male. The incision height
was from 20% to 80% corneal depth, with a 7.0- or 8.0-mm
OZ. The astigmatic correction was titrated by varying the arc
angle between 30 and 75 degrees. Results: The mean absolute
preop cylinder of -1.28 ± 0.60 D (range: -0.50 to -3.50 D) was
reduced to -0.60 ± 0.53 D (range: 0.00 to -2.75 D). Undercorrection of the cylinder was also indicated with the correction ratio
of 0.72. There was no change in MSE: preop -0.05 ± 0.50 D and
postop +0.10 ± 0.47 D. UCVA improved, with 26% and 52%
of eyes achieving 20/16 and 20/20 unaided vision at 3 months,
compared to 4% and 18% preoperatively. There was no mean
change in BCVA, and no eye lost more than 2 lines of vision.
Conclusion: Intrastromal femtosecond astigmatic keratotomy is
a viable technique to correct low to moderate levels of astigmatism. Further refinement of the nomogram by adjusting the OZ
and arc angle may improve the predictability of outcomes.
Femtosecond Laser Astigmatic Keratotomy in
Patients With Mixed Astigmatism After Previous
Refractive Surgery
Presenting Author: Jan A Venter MD
Coauthor: Steven C Schallhorn MD
Purpose: To report the results of correction of mixed astigmatism
with femtosecond laser intrastromal astigmatic keratotomy in
patients with previous refractive surgery. Methods: 112 eyes
with a history of previous excimer laser surgery, refractive lens
exchange, or phakic IOL implant with low amounts of mixed
astigmatism underwent femtosecond-assisted astigmatic keratotomy using paired symmetrical intrastromal arcuate keratotomies
created 60 µm from surface to 80% depth at 7-mm diameter.
Outcome measures included uncorrected distance visual acuity
(UDVA), corrected distance visual acuity (CDVA), subjective
refraction, and keratometry. Holladay-Carvy-Koch method
was used to calculate the surgically induced refractive change
(SIRC). A coupling ratio was calculated to assess the change in
spherical equivalent. Average follow-up was 7.6 ± 2.9 months.
Results: The mean UDVA improved from 0.18 ± 0.14 logMAR
to 0.02 ± 0.12 logMAR, which was statistically significant (P <
.01). The mean absolute value of subjective cylinder was 1.20 ±
0.47 D preoperatively and 0.55 ± 0.40 D postoperatively (P <
.01). Subjective sphere reduced from +0.61 ± 0.33 D to +0.17 ±
0.36 D (P < .01). The mean CDVA was -0.03 ± 0.08 logMAR
preoperatively and -0.05 ± 0.09 logMAR postoperatively, which
was not statistically significant (P = .06). The coupling ratio was
0.92 ± 0.45. No surgical complications occurred in this study.
Conclusion: Intrastromal astigmatic keratotomy performed with
the femtosecond laser was effective in reducing refractive error
in patients where other surgical options were exhausted. Predictability and efficacy could be improved with a more accurate
nomogram.
Vision and Spectacle Independence After Bilateral
Implantation of +3D Diffractive Toric and Nontoric
Multifocal IOLs
Presenting Author: Michael C Knorz MD
Purpose: To compare results after implantation of either a toric
or a nontoric multifocal IOL. Methods: A prospective, multicenter study of 49 patients with a toric multifocal (ReSTOR
+3 D Toric) IOL were evaluated and compared to those of 139
patients with a nontoric multifocal (ReSTOR +3 D) IOL treated
in a separate prospective, multicenter study. Results: Mean
UCVA were consistent between the 2 groups. Overall spectacle
independence was over 78% for both groups. Conclusions: Both
the nontoric and the toric multifocal IOLs provide good uncorrected distance, intermediate, and near visual acuity, with spectacle independence greater than 78%.
79
Prospective Comparison of 3 Presbyopia-Correcting
IOLs
Presenting Author: Robert Edward T Ang MD
Purpose: To compare the refractive and visual outcomes and
contrast sensitivity of 3 presbyopia-correcting lenses. Methods: This is a prospective, randomized, subject-masked bilateral study. Seventy-eight patients were randomly implanted
with either Crystalens AO, ReSTOR +3, or Tecnis Multifocal
bilaterally during cataract surgery. Follow-up was 6 months.
Results: At the 6-month follow-up, the mean SE was -0.34 D
for Crystalens, -0.07 D for Tecnis, and -0.12 D for ReSTOR.
Mean high contrast UDVA was 20/20 for the Crystalens, 20/20
for the Tecnis, and 20/25 for the ReSTOR group. Mean UIVA
was 20/20 for the Crystalens and 20/25 for both the Tecnis
and ReSTOR group. Mean UNVA was 20/25 for the 3 groups.
Mesopic contrast sensitivity without glare was better in the Crystalens vs. Tecnis at 1.5 c/deg (P < .001) and 3c/deg (P = .009) and
better than ReSTOR at 3c/deg (P = .046). Conclusions: Mildly
myopic refractive outcomes for the Crystalens and emmetropic
outcomes for the Tecnis and ReSTOR were achieved. High contrast distance and near vision were similar between the 3 lenses.
Intermediate vision and contrast sensitivity were better with the
Crystalens.
Laser Refractive Lens Surgery: The Value
Proposition From My Perspective as a Patient
Presenting Author: Daniel S Durrie MD
Coauthors: Jason E Stahl MD, Jason P Brinton MD
Purpose: To describe the value proposition of laser refractive lens
surgery from the perspective of a patient. Methods: A 62-yearold refractive surgeon (DSD) with a history of LASIK O.U. and
mild monovision noted a progressive loss of UNVA over 3-6
months. UDVA O.U. was 20/20 and UNVA O.U. 20/30. The
patient desired refractive lens exchange with -0.87 D target using
a monofocal lens in the nondominant eye to preserve his mild
monovision. Femtosecond laser lens technology and intraoperative aberrometry were discussed. The patient felt that he had the
greatest chance of obtaining the chosen refractive target with a
round, centered, laser capsulotomy and intraoperative aberrometry to guide selection of the correct lens power. Results: Postoperative UDVA O.U. was 20/20 with UNVA O.U., 20/16. MRx
in the operative eye was -0.87 D as targeted with 20/16 CDVA.
The patient (DSD) reported an increased confidence in the procedure outcome while undergoing the procedure knowing that
the femtosecond laser and intraoperative aberrometry would be
employed. The experience from the patient’s perspective will be
related in detail. Conclusion: Femtosecond laser and intraoperative aberrometry technologies can add significant value to the
patient undergoing refractive lens exchange.
80
Multicenter Clinical Evaluation of Hydrophobic
Aspheric Diffractive 1-Piece Multifocal IOL
Presenting Author: Elizabeth A Davis MD
Purpose: To report clinical effectiveness, patient satisfaction,
and surgeon assessment of a hydrophobic-acrylic, aspheric, diffractive multifocal IOL. Methods: Three month follow-up of
106 patients bilaterally implanted with a 1-piece multifocal IOL
(Tecnis multifocal IOL, TMF) collected from 17 sites. Binocular
uncorrected and distance-corrected visual acuities (VAs) at distance, intermediate, and near. Survey of patient satisfaction and
surgeon assessment of the TMF. Results: Binocular uncorrected
VAs of 20/25 or better and 20/40 or better were achieved by
85% and 98% of patients at distance, 49% and 89% of patients
at intermediate, and 80% and 98% of patients at near, respectively (n = 98). Binocular distance corrected VAs of 20/25 or
better and 20/40 or better were achieved by 99% and 100% of
patients at distance, 62% and 85% of patients at intermediate,
and 90% and 100% of patients at near, respectively (n = 86).
Halos were moderately or very bothersome for 23% of patients
and glare for 24%. Vision correction was never worn by 90%
of patients, and 83% were definitely or most likely to choose the
same IOL again. Of surgeons surveyed, 78.5% felt the TMF performed better than other multifocals they had used, and 92.9%
would recommend it to friends and family. Conclusion: The
TMF demonstrated good clinical effectiveness, high patient satisfaction, and positive surgeon assessment.
Section V: ESCRS Symposium: Corneal Refractive Surgery
81
All Femtosecond Laser LASIK: ReLEx-SMILE
Jose L Güell MD
Introduction
Since femtosecond lasers were first introduced into refractive
surgery, the ultimate goal has been to create an intrastromal
lenticule that can be removed in one piece manually, thereby
avoiding the need for photoablation by an excimer laser. A precursor to modern ReLEx was first described in 1996; it used a
picosecond laser to generate an intrastromal lenticule that was
removed manually after lifting the flap.1,2 However, significant
manual dissection was required, leading to an irregular surface.
The switch to femtosecond improved the precision,3 and studies
were performed in rabbit eyes in 19984 and in partially sighted
eyes in 2003.5 However, these initial studies were not followed
up with further clinical trials.
Following the introduction of the VisuMax femtosecond
laser (Carl Zeiss Meditec; Jena, Germany) in 2007,6 the intrastromal lenticule method was reintroduced in a procedure called
Femtosecond Lenticule Extraction (FLEx). The 6-month results
of the first 10 fully seeing eyes treated were published in 2008,7
and results of a larger population have since been reported.8 The
refractive results were similar to those observed in LASIK, but
visual recovery time was longer due to the lack of optimization in
energy parameters and scan modes; further refinements have led
to much improved visual recovery times.9
Following the successful implementation of FLEx, a new
procedure called small incision lenticule extraction (SMILE) was
developed. This procedure involves passing a dissector through a
small (2-3 mm) incision to separate the lenticular interfaces and
allow the lenticule to be removed, thus eliminating the need to
create a flap. The results of the first prospective trials of SMILE
have been reported,10,11 and there are now more than 50 surgeons routinely performing this procedure worldwide.
The VisuMax system is designed for coupling of the femtosecond laser source to the cornea with minimal tissue distortion and
rapid high-precision femtosecond pulse placement.
The main characteristics of the VisuMax system are as follows:
1. The VisuMax coupling contact glass interface with the
cornea is curved, thus leading to very little corneal distortion when securing full corneal surface contact.
2. Corneal coupling of the contact glass is achieved with very
low suction force applied though specifically designed suction ports that are applied to the peripheral cornea/limbus,
but not the corneal conjunctiva/sclera. This low suction
coupling force minimizes corneal distortion.
3. Each contact glass is individually calibrated by a built-in
optical coherence imaging system, thus compensating for
individual differences in contact glass geometry that are
inevitable in serial production.
4. The optical beam path system coupled to the contact glass
is suspended on a fulcrum. The fulcrum, together with a
continuous force-feedback servo control for patient bed
height, produces a system delivering a constant force of the
contact glass onto the cornea. This constant force minimizes changes in corneal distortion that may occur with
patient head movement during the femtosecond cutting
process.
5. The optical system delivering the femtosecond beam is
designed with very high numerical aperture optics, thus
allowing for very tight concentration of femtosecond
energy, very little collateral energy dissipation and high
femtosecond spot placement accuracy.
6. The laser-tissue interaction dynamics are optimized for
speed with a repetition rate of 500 kHz, which minimizes
treatment time and achieves the critical refractive cuts in a
short enough time to reduce the chances of eye or patient
movements during this phase of the cutting.
The Procedure
1. The VisuMax is prepared for the procedure by the attachment of a disposable curved contact glass onto the laser
aperture cone. It is useful to select the smallest possible
treatment pack. If the selected suction ring is too large, it
may cause suction pressure on the conjunctiva, resulting in
premature abortion of the treatment due to loss of suction.
2. The contact glass has a curved surface designed to couple
with the cornea. Before coupling, the VisuMax system selfcalibrates the contact glass. Also, the eye’s keratometry
data are entered into the VisuMax to account for the difference between the relaxed cornea and the contact glass
curvature. This allows the system to calculate the ratio
between the intended clinical treatment and cap diameter
on the relaxed eye and the technical incision diameter
when cutting the eye coupled to the contact glass. The
patient bed is moved using a joystick which controls x-y
and z so that the eye is brought up into contact with the
contact glass, while the patient is fixating on a flashing
green light.
3. Once contact is made between the cornea and the contact
glass, the patient is able to see the flashing fixation target
in clear focus, as it uses the manifest refraction of each
individual eye. This aligns the eye in the primary position,
allowing the bed to be raised vertically while the surgeon
observes the alignment of the contact glass application
through the operating microscope and the side screen.
4. Then the cornea applanates in a self-entering way on the
corneal vertex followed by application of suction, the eye
is immobilized by low corneal suction, where the IOP
increases with the VisuMax is low enough for the patient
to see throughout the procedure, and the laser is activated
by the surgeon pressing on a foot pedal.
5. Then the patient is moved to the observation microscope
and manual dissection is performed, starting with the
upper surface dissecting the cap from lenticule first, then
we dissect the lenticule from the stromal bed. Then the
lenticule is removed with a forceps through a 3-4 mm incision.
82
Advantages of ReLEx SMILE Over LASIK
These new femtosecond intrastromal lenticule procedures offer a
number of potential advantages:
1. More accurate and repeatable tissue removal independent
of prescription treated
2. Increased biomechanical integrity of the postoperative cornea
3. Reduction in postoperative dry eye symptoms and recovery
In our presentation we will present a resume of the latestupdate international clinical, refractive, confocal microscopy and
pathological data as well as the projects going on.
Surgical Technique
Figures 1-11: Consecutive images of the steps of the procedure from
laser lenticule cut to refractive lenticule extraction through careful plane
dissection.
Figure 3.
Figure 1.
Figure 4.
Figure 2.
Figure 5.
Figure 6.
Figure 9.
Figure 7.
Figure 10.
Figure 8.
Figure 11.
83
84
Clinical Cases
Figure 12. 24 hours postoperative OCT and
slitlamp view. Observe the quality of the cut.
Figure 13. Two months’ follow-up of a SMILE
case. Observe the OCT scan, Orbscan topography, and OQASPSF.
References
1. Ito M, Quantock AJ, Malhan S, Schanzlin DJ, Krueger RR. Picosecond laser in situ keratomileusis with a 1053-nm Nd:YLF laser. J
Refract Surg. 1996; 12(6):721-728.
4. Heisterkamp A, Mamom T, Kermani O, et al. Intrastromal refractive surgery with ultrashort laser pulses: in vivo study on the rabbit
eye. Graefes Arch Clin Exp Ophthalmol. 2003; 241(6):511-517.
2. Krueger RR, Juhasz T, Gualano A, Marchi V. The picosecond laser
for nonmechanical laser in situ keratomileusis. J Refract Surg. 1998;
14(4):467-469.
5. Ratkay-Traub I, Ferincz IE, Juhasz T, Kurtz RM, Krueger RR.
First clinical results with the femtosecond neodynium-glass laser in
refractive surgery. J Refract Surg. 2003; 19(2):94-103.
3. Kurtz RM, Horvath C, Liu HH, Krueger RR, Juhasz T. Lamellar
refractive surgery with scanned intrastromal picosecond and femtosecond laser pulses in animal eyes. J Refract Surg. 1998; 14(5):541548.
6. Reinstein DZ, Archer TJ, Gobbe M, Johnson N. Accuracy and
reproducibility of artemis central flap thickness and visual outcomes of LASIK with the Carl Zeiss Meditec VisuMax femtosecond
laser and MEL 80 excimer laser platforms. J Refract Surg. 2010;
26(2):107-119.
7. Sekundo W, Kunert K, Russmann C, et al. First efficacy and safety
study of femtosecond lenticule extraction for the correction of myopia: six-month results. J Cataract Refract Surg. 2008; 34(9):15131520.
8. Blum M, Kunert KS, Engelbrecht C, Dawczynski J, Sekundo
W. [Femtosecond lenticule extraction (FLEx): results after 12
months in myopic astigmatism]. Klin Monbl Augenheilkd. 2010;
227(12):961-965.
9. Shah R, Shah S. Effect of scanning patterns on the results of femtosecond laser lenticule extraction refractive surgery. J Cataract
Refract Surg. 2011; 37(9):1636-1647.
10. Sekundo W, Kunert KS, Blum M. Small incision corneal refractive
surgery using the small incision lenticule extraction (SMILE) procedure for the correction of myopia and myopic astigmatism: results
of a 6 month prospective study. Br J Ophthalmol. 2011; 95(3):335339.
11. Shah R, Shah S, Sengupta S. Results of small incision lenticule
extraction: all-in-one femtosecond laser refractive surgery. J Cataract Refract Surg. 2011; 37(1):127-137.
85
86
Customized Transepithelial No-touch Refractive and
Therapeutic Procedures
Xiangjun Chen MD, Aleksandar Stojanovic MD
The transepithelial ablation, although previously attempted
with the first generation of excimer lasers by use of consecutive
PTK and PRK for epithelial removal and refractive ablation,
respectively, has become possible only lately after the introduction of the very high-frequency small flying spot laser technology
required for the timely ablation of the high volume that the epithelial removal represents and to ensure the necessary smoothness of the ablation surface.
The cTEN-ablation consists of a refractive part, which
reshapes the corneal surface within the treatment zone into an
aspheric regular shape of desired curvature, and a lamellar part,
which translates that shape below the epithelium (see Figure 1).
These two parts are summed and executed in a single uninterrupted ablation, lasting typically 20-35 secs. The patient’s refraction, corneal Scheimpflug elevation, pachymetry maps, pupillometry, as well as the pupil, iris, and scleral vessel registration
information are imported into the ablation planning software,
with the aim of reshaping the detected corneal surface into a
regular aspheric surface within a treatment zone suggested by
pupillometry. Published data show a relatively small difference
in the ablation rate between epithelium and stroma (0.55 ± 0.1
vs. 0.68 ± 0.15 µm per pulse),1 but the difference in ablation
rate between epithelium and stroma seem to differ among the
lasers depending on their energy fluence, shot pattern, and frequency. The 1KHx iRES laser used in the present study optimizes
laser energy, fluence, shot pattern, and frequency to minimize
differences in ablation rates between the epithelium and the
stroma. A former study by our research group demonstrated
that transepithelial surface ablation using the iRES laser speeded
reepithelialization and reduced postoperative pain compared to
traditional PRK with Allegretto 400 Hz laser using Amois brush
for deepithelialization.2
Using topography-guided custom ablation implies correction
of higher-order aberrations (HOAs) originating only from the
corneal surface, which are responsible for the majority of light
refraction in the eye. Furthermore the corneal HOAs are static
and hence more appropriate as a target for treatment than the
dynamic HOAs of crystalline lens. In addition to correcting the
corneal surface HOAs, the current topography-guided ablation
creates a customized transition that keeps a constant dioptric
gradient toward the untreated cornea, instead of employing
commonly used fixed transition zone diameter. This may lead to
lower regression by preventing any counterproductive epithelial
remodeling.
Figure 1. Preoperative corneal surface with the epithelium (upper gray
line) (a), is reshaped into a regular aspheric surface of desired curvature
(b) and the new surface is transferred below the epithelium (c) in a single
noninterrupted ablation.
We retrospectively analyzed 17 consecutive symptomatic
eyes of 16 patients with LASIK flap or interface complications3,4
(post-LASIK complication group), as well as 117 consecutive virgin eyes of 61 patients treated for myopic astigmatism (myopic
astigmatism group) at SynsLaser Clinic in Tromsø, Norway.
For the post-LASIK complication group, mean corrected
distance visual acuity (CDVA) improved from 20/28 to 20/19,
with 64.7% of eyes gaining 2 or more lines. Among those eyes
who had irregular astigmatism with irregularity index >10 and
orthogonal curvature asymmetry > 1.00 D within the central
4 mm, the irregularity index changed from 28.82 ± 12.82 μm
to 20.36 ±10.64 μm, whereas asymmetry changed from 3.74 ±
2.22 D to 2.16 ± 1.19 D. The average HOAs root-mean-square
(RMS) at 5-mm diameter decreased by 62.3% from 1.30 to 0.49,
the average odd-order (third and fifth orders) RMS and evenorder (fourth and sixth orders) RMS decreased by 55.3% from
0.85 to 0.38 and by 44.2% from 0.43 to 0.24, respectively. The
patients’ subjective evaluation showed that in 47.1% and 52.9%
of eyes, visual symptoms were claimed to be better and cured,
respectively. No eyes were claimed to be unchanged or worse.
For the virgin eyes treated for myopic astigmatism, mean
preoperative spherical equivalent (SE) was -3.22 ±1.54 D (range
-0.63 to -7.25 D) and the mean cylinder was -0.77 ±0.65 D
(range 0 to -4.50 D). Efficacy index (postoperative UDVA/preoperative CDVA) was 0.91, 1.00, 1.09, and 1.09 at 1, 3, 6, and 12
months postoperatively, respectively. All eyes were within ±1.0 D
of emmetropia, 94% of eyes were within ±0.5 D of emmetropia
at 12 months, and 97% of eyes had refractive astigmatism less
or equal to 0.5 D at 12 months postoperatively. Postoperative
SE stability was reached at 1 month postoperatively. The safety
index (postoperative CDVA/preoperative CDVA) was 1.27 for
both 6 and 12 months. Postoperatively, RMS of total HOAs and
coma-type aberrations increased, while the spherical aberration
showed no statistically significant change.
The idea of one-step “no-touch” laser treatment appeals to
the patients because it is much quicker and more comfortable
than traditional excimer laser surgery. The main appeal of this
procedure to the surgeon is its perceived lack of serious complications as well as ease and speed of performance.
In conclusion, the outcomes of this study suggest that transepithelial topography- guided surface ablation, which integrates
epithelial debridement and refractive error correction into a
single custom ablation, is safe, effective, and predictable in treatment of irregular astigmatism after LASIK and in treatment of
low to moderate myopic astigmatism in virgin eyes. The same
technology was also successfully applied in conjunction with
corneal collagen crosslinking in treatment of keratoconus and
pellucid marginal degeneration (PMD).5
87
References
1. Seiler T, Kriegerowski M, Schnoy N, Bende T. Ablation rate of
human corneal epithelium and Bowman’s layer with the excimer
laser (193 nm). Refract Corneal Surg. 1990; 6:99-102.
2. Chen X, Stojanovic A, Oeritsland H. Transepithelial custom ablation vs PRK with mechanical epithelial removal. comparison of
postoperative pain, reepithelialization speed and early visual outcomes. Presented at the XXVIII Congress of the European Society
of Cataract and Refractive Surgeons; Paris; 2010. Reference available at: http://escrs.org/publications/eurotimes/11March/no-touch
.pdf. Accessed September 25, 2011.
3. Chen X, Stojanovic A, Zhou W, Utheim TP, Stojanovic F, Wang
Q. Transepithelial, topography-guided ablation in the treatment
of visual disturbances in LASIK flap or interface complications. J
Refract Surg. 2012; 28:120-126.
4. Chen X, Stojanovic A, Nitter TA. Topography-guided transepithelial surface ablation in treatment of recurrent epithelial ingrowths. J
Refract Surg. 2010; 26:529-532.
5. Stojanovic A, Zhang J, Chen X, Nitter TA, Chen S, Wang Q.
Topography-guided transepithelial surface ablation followed by
corneal collagen cross-linking performed in a single combined
procedure for the treatment of keratoconus and pellucid marginal
degeneration. J Refract Surg. 2010; 26:145-152.
88
Pinhole
The KAMRA (Depth-of-Focus) Corneal Inlay for the Correction of Presbyopia
Günther Grabner MD, Theresa Rückl MD, Wolfgang Riha MD, Orang Seyeddain MD, Alois Dexl MD
The focus of interest in refractive surgery has, in recent years,
clearly shifted toward the goal of optimizing the correction of
presbyopia. The sheer number of potential patients who might
seek spectacle- and contact-lens-free permanent correction certainly is a great stimulus for clinical research and many corneal
procedures (eg, thermokeratoplasty, conductive keratoplasty,
presbyLASIK, intracorneal implants) have been introduced with
sometimes debatable results into the clinical practice.
An ultrathin depth-of-focus intracorneal inlay (KAMRA from
AcuFocus; Calif.) (New design, see Figure 1) implanted monocularly into the intermediate corneal stroma (around 200µ depth)
in the nondominant eye offers a new alternative (see Figure 2)
for the correction of presbyopia in simple emmetropic eyes or in
cases when LASIK is simultaneously performed for the correction of ametropias.1-3
The study design in the longest follow-up series today is
shown in Figure 3. The surgical procedure is quite simple and
fast (see Figure 4) with centration being of major importance as
has been shown in several studies.
Figure 3.
Figure 1.
Figure 4.
In case of decentration in this first series of 32 patients with
the initial design, 2 patients regained excellent distance and near
visual acuity following recentration of about 0.5 mm in each case
several months after initial KAMRA placement (see Figures 5
and 6). They have remained stable since.
Figure 2.
89
Figure 5.
Figure 8.
Figure 6.
Figure 9.
Results of a series with a long-term follow-up of 60 months
are shown in Figure 7. A new study with 2-year follow-up and
implantation in a FS laser-created pocket has recently been published4 (see Figures 8 and 9).
Patient satisfaction was very high (see Figure 10), with all
patients reporting to drive at night without glasses, and all stating that they would have the surgery again. In a separate study
it was shown that all glaucoma and retinal exams (tonometry,
OCT, GDx, goniolens, visual fields, funduscopy) could be reliably performed.
Figure 7.
90
References
1. Yilmaz ÖF, Bayraktar S, Agca A, Yilmaz B, McDonald MB, van de
Pol C. Intracorneal Inlay for the surgical correction of presbyopia. J
2. Seyeddain O, Riha W, Hohensinn M, Nix G, Dexl AK, Grabner
G. Refractive surgical correction of presbyopia with the Acufocus
small aperture corneal inlay: two-year follow-up. J Refract Surg.
2010; 26:705-715.
3. Dexl AK, Seyeddain O, Riha W, Hohensinn M, Hitzl W, Grabner
G. Reading performance after implantation of a small-aperture
corneal inlay for the surgical correction of presbyopia: two-year
follow-up. J Cataract Refract Surg. 2011; 37:525-531.
4. Seyeddain O, Bachernegg A, Riha W, Rückl T, Reitsamer H, Grabner G, Dexl A. Two year follow-up of 24 patients after small aperture corneal inlay implantation for the correction of presbyopia. J
Cataract Refract Surg. 2012. In press.
Figure 10.
The KAMRA inlay offers a variety of options in myopic,
hyperopic, and emmetropic presbyopic as well as pseudophakic
patients with excellent distance vision retained (in the implanted
eye!) and has a follow-up of more than 5 years. It has successfully been implanted in > 15,000 patients worldwide until now
and is rapidly gaining great popularity.
91
Hydrogel: Swiss Project
A Novel Corneal Inlay for the Treatment of Presbyopia:
The ICOLENS Experience
Thomas Kohnen MD PhD FEBO, Michael O’Keefe MD
Purpose
Results
To evaluate near and distance visual performance, patient satisfaction, and complications after monocular implantation of a
novel bifocal intrastromal lens. (preliminary results).
Fifty-two implantations where performed. Sixty percent of
patients gained 2 or more lines in near visual acuity, 34% gained
3 or more lines. Seventy-seven percent of patients reached Nieden 8 or better. Fifty-two percent of patients had no change
in uncorrected distance visual acuity, 30% lost 1 to 2 lines, no
patient lost more than 2 lines. Mean increase in cornel curvature
was 0.20 ± 0.78 D (central SIM-K values), ranging from -3 D to
+2 D. 100% of patients were satisfied with the procedure in general, 86% did not feel their distance vision was impaired (14%
reported “sometimes”) and 100% did not experience any pain or
discomfort in their eye. Six patients reported mild or intermittent
glare without subjective impact on their driving abilities. No corneal complications or adverse events occurred.
Material and Methods
Prospective consecutive clinical trial. Inclusion criteria were an
age of 45-65 years, manifest distance spherical equivalent (SE)
between -0.25 and +1.0 D, < ± 1.0 D of manifest astigmatism,
wearing of reading glasses for all near tasks, uncorrected near
vision (UNVA) of ≤ 0.4 logMAR, pupil diameter of 2.4 to 4.2
mm at “mesopic high” conditions (609 lux), central corneal
thickness (CCT) of > 500 µm, clearly determined ocular dominance, and a minimum endothelial cell density of 2000 cells/
mm2. Exclusion criteria were profession of pilot or professional
driver, ocular pathologies, any acute or chronic systemic disease/
medications that may reduce healing, emotional problems that
may interfere with ability to undergo procedure, clinically dry
eyes, and severe allergies.
The implanted lens (ICOLENS, Neoptics) has a diameter
of 3.0 mm, an edge thickness of ≤ 15 µm and a central hole of
0.15 mm to facilitate nutrient flow. It is made of a copolymer of
HEMA and MMA (hydrogel properties). The lens offers a bifocal optic design, with a central zone for distance vision and a
peripheral positive refractive zone for near vision. It is implanted
in the non-distance-dominant eye via a femtosecond laser tunnel
cut (Ziemer LDV). At each follow-up visit (1 day, 1 week, 1, 3,
5 and 12 months) objective and subjective refraction, visual acuity (near and distance), corneal topography (Orbscan), a patient
satisfaction questionnaire, and adverse events monitoring where
performed.
Conclusion
The novel corneal inlay is reversible and well tolerated and offers
quick implantation and fast recovery. However, the technical
procedure has a certain learning curve and the implant shows
improvable results in certain patients despite excellent surgical
outcome and appropriate lens selection.
92
Hydrogel: Flexivue Project
Ioannis G Pallikaris MD, D Bouzoukis MD, A Limnopoulou MD MSc, S Panagopoulou PhD,
A Pallikaris MSc, G Kymionis MD PhD
Purpose: To investigate the visual outcomes and safety of intracorneal lenses (Flexivue Micro-Lens, Presbia; Los Angeles,
Calif., USA) for presbyopia implanted using femtosecond laser
(Intralase, AMO; Irvine, Calif., USA). Methods: The lens was
implanted inside a corneal pocket created in the nondominant
eye of 40 patients using femtosecond laser. Results: Mean uncorrected visual acuity for near increased from 20/100 to 20/25
and for distance decreased from 20/20 to 20/40 in the operated eye, whereas it remained stable binocularly. After surgery,
92% referred no use of reading glasses. No intra/postoperative
complications were found. Conclusions: Intracorneal lenses for
presbyopia are a safe and effective method in patients aged 45 to
60 years old.
93
Combined PRK-Collagen Crosslinking in Keratoconus
Suspects and Forme Fruste
Purpose
Summary
To explore the clinical effect of photoablation on ectatic corneas
if combined with corneal crosslinking.
CCL offered the opportunity of refractive correction for patients
with satisfactory spectacle vision. As corneal ectatic disorders
may be slow, long follow-up may establish this modality as
a standard treatment . Limits and indications are still to be
explored.
Methods
Forty-nine eyes of 28 patients underwent collagen crosslinking
(CCL)-PRK for the correction of myopic and mixed astigmatism.
Mean patients age was 28 years, ranging from 18 to 36 years.
Mean attempted correction was -2.16 ± 1.36 D, ranging from
1 to -3.75 D. Minimum corneal thickness was of 458 microns,
and maximum ablation did not exceed 60 microns. Enrolled eyes
had topographic pattern of subclinical keratoconus (KC) (12
patients), clinical KC, or were fellow eyes of KC (14 patients)
and had satisfactory best spectacle correction. Surgeries were
performed with the WaveLight Allegretto laser platform, with
conventional treatments, at a single eye session, having laser
ablation first with use of mitomycin C, followed by 1 hour CCL
(Dresden protocol). All reported eyes completed at least 12
months of follow-up.
94
Accuracy of Corneal Astigmatism Prediction With
Various Devices
Presenting Author: Douglas D Koch MD
Coauthors: Richard Jenkins MD, Mitchell P Weikert MD,
Elizabeth Yeu MD, Li Wang MD
Purpose: To evaluate the accuracy of 5 devices for calculating
corneal astigmatism (CA) for toric IOL selection. Methods:
We measured CA with the IOLMaster, Lenstar, Atlas, manual
keratometer, and Galilei. Thirty-three eyes of 33 patients were
measured with all 5 devices preoperatively and 3 weeks postoperatively. Based on the steep anterior corneal meridian, eyes were
divided into with-the-rule (WTR, 60-120º) and against-the-rule
(ATR, 0-30º and 150-180º), and oblique (30-60º and 120-150º)
astigmatism groups. Manifest refraction (MR) and postoperative
toric IOL alignment were measured. Using vector analysis, the
anticipated CA was calculated as the sum of astigmatism from
postop MR and the effective toric power at corneal plane as calculated with the Holladay 2 consultant. The CA prediction error
(PE) was then calculated by subtracting the anticipated CA from
the CA measured by each device. Results: For the IOLMaster,
Lenstar, Atlas, manual keratometer, and Galilei, respectively, the
mean PEs were 0.53 D@99º, 0.54 D@105º, 0.26 D@106º, 0.45
D@104º, and 0.39 D@103º in the WTR eyes, and 0.29 D@81º,
0.21 D@89º, 0.38 D@95º, 0.40 D@64º, and 0.18 D@17º in
ATR eyes. The posterior cornea as measured by the Galilei was
steeper vertically in all eyes, resulting in mean effective powers of
the posterior CA of 0.38 D@9º and 0.11 D@172º in WTR and
ATR eyes, respectively. These measured values were slightly less
than the magnitude of posterior CA that we calculated from the
postoperative results. Conclusion: All 5 devices predicted more
WTR astigmatism, or, with the exception of the Galilei, less ATR
astigmatism than we found clinically. In selecting a toric IOL,
ignoring posterior CA could lead to overcorrection of WTR and
undercorrection of ATR CA.
New Excimer Laser Custom Strategy: Asymmetric
Centration Combining Pupil and Corneal Vertex
Information
Presenting Author: Paolo Vinciguerra MD
Coauthors: Fabrizio I Camesasca MD, Samuel Arba
Mosquera MS
Purpose: We present a method for centering excimer laser ablation profiles (AP) by simultaneous integration of pupil center
(PC) and corneal vertex (CV) information. Methods: We developed AP covering the pupil aperture while maintaining the CV
as the ablation optical axis (asymmetric offset, AO). PC (lineof-sight) high-order aberrations (HOA) were combined with
manifest refraction values referred to the CV. Results: AO leads
to no-offset-like depth and size asymmetric AP. When combined
with HOA ablation plan, AO spheric and astigmatic components
influence, respectively, coma and trefoil components. Conclusion: AO AP combine pupil and corneal vertex information with
ablation axis positioned on visual axis. Edges of the optical zone
are concentric to the pupil. This reduces HOA.
A Measure of Corneal Astigmatism That
Corresponds to Manifest Refractive Cylinder Corneal
Topographic Astigmatism (CorT)
Presenting Author: Noel A Alpins MD FACS
Purpose: To determine a measure of corneal astigmatism that
correlates well with manifest refractive cylinder. Methods: 486
right eyes and 485 left eyes were analyzed preoperatively on
the Zeiss Atlas 9000. Twelve right eyes and 13 left eyes were
excluded because more than 10% of the topographic data was
missing due to upper lid interference. Measurements were performed between June 2009 and August 2011. Right eye and left
eye data were analyzed separately to ensure that observations
were independent. Keratometric data were measured with a Topcon OM-4 keratometer. Using all the Placido ring data available
from topography, an astigmatism value was calculated for each
ring followed by a summated vector mean on the total rings,
resulting in a measurement known as corneal topographic astigmatism (CorT). This was then compared to the refractive cylinder measured subjectively using the ocular residual astigmatism
(ORA). The spread in ORA for the CorT was then compared
against other measures of corneal astigmatism: simulated keratometry (Sim K), manual keratometry (manK), corneal wavefront (CorW), and paraxial curvature matching (PCM). Results:
CorT had a better correlation and less spread with manifest
refractive cylinder than sim K, man K, CorW, and PCM. Conclusions: An alternative measure of corneal astigmatism, known as
CorT, corresponds more closely to the manifest refractive cylinder than other measures of corneal astigmatism.
95
Three-Dimensional Spectral-Domain OCT Analysis
of a Prospective Contralateral Femtosecond LASIK
Study for Myopia
Refractive, Visual, and Clinical Outcomes of
Femtosecond Lenticule Extraction FLEx vs. FemtoLASIK Treatments for Myopia
Presenting Author: Karolinne M Rocha MD
Presenting Author: Diana F Rodriguez-Matilde MD
Coauthors: Brent Timperley MD, Ronald R Krueger MD
Purpose: To compare femtosecond LASIK flap architecture and
epithelial thickness profile after flap creation with IntraLase
FS60 in one eye and WaveLight FS200 in the fellow eye using
a spectral domain OCT. Methods: Twenty-four eyes of 12
patients underwent femto-LASIK with Allegretto Eye-Q Laser.
The randomization was obtained for IL60 in one eye and FS200
in the fellow eye. All flaps were created by a single surgeon
and an intended flap thickness of 110 µm. Spectral domain
OCT (Optovue-RTVue) was used to evaluate flap architecture
and epithelial thickness profile preoperatively, 1 week and 3
months postop. Segmentation of the images was performed in
8 meridians for total thickness, flap thickness, and epithelialBowman transition. The average thickness of the central (2 mm),
superior, and inferior zones (2-5 mm) was calculated. Results:
Significant epithelial thickening was observed in both groups
centrally and inferiorly at 3 months (P = .033 and P = .007).
Three-dimensional flap thickness analysis revealed thickening of
the flap at 3 months postop. Mean flap thickness in the FS200
group was 106.78 ± 3.93 centrally, 108.0 ± 5.24 inferiorly, and
106.11 ± 4.88 superiorly at 1 week and 109.78 ± 5.63, 111.33
± 8.44, and 107.67 ± 5.74 at 3 months, respectively. Mean flap
thickness in the IL60 group was 107.44 ± 4.03 centrally, 110.11
± 5.11 inferiorly, and 109.56 ± 4.88 superiorly at 1 week and
115.11 ± 4.37, 116.56 ± 7.62, and 114.44 ± 6.50 at 3 months.
The FS200 flaps were slightly thinner and significant differences
were observed centrally (P = .039) and superiorly (P = .032) at
3 months. Conclusion: Significant epithelial and flap thickening
were observed at 3 months postop. Spectral domain OCT analysis of FS200 vs. IL60 Femto-flaps revealed slightly thinner flaps
with the FS200.
Coauthors: Zoraida B Espinoza-Mattar MD, Martha Jaimes
MD, Alejandro Navas MD, Tito Ramirez-Luquin MD, Enrique
O Graue-Hernandez MD, Arturo J Ramirez-Miranda MD
Purpose: To evaluate outcomes using femtosecond lenticule
extraction (FLEx) vs. femtosecond-assisted LASIK (F-LASIK).
Methods: Forty-six eyes of 23 patients were randomly distributed into 2 groups in a prospective study. For each patient one
eye was treated with FLEx using just the Visumax femtosecond
laser (Carl Zeiss Meditec; Germany) (n = 23) and the other eye
with F-LASIK using the Visumax for flap creation followed by
excimer laser ablation with a MEL80 excimer laser (n = 23).
Follow-up was done at 1 day, 1 week, and 1, 3, and 6 months.
UDVA, CDVA, subjective refraction, and corneal tomography
were recorded at each visit. Results: Forty-six eyes were treated.
Follow-up was 6 months. Preoperative mean logMAR UDVA
was 1.8 ± 0.08 and 1.8 ± 0.09, and postoperative mean logMAR
was 0.06 ± 0.05 and 0.06 ± 0.04 in the flex FLEx F-LASIK
groups, respectively. Preop mean spherical equivalent was -5.21
D ± 0.44 and -5.33 D ± 0.25, and postop mean spherical equivalent was -0.12 D and -0.85 in both groups, respectively. Differences in UDVA and SE were statically significant (P < .05, t-test).
On the satisfaction poll, the patient preferred the FLEx procedure over LASIK, but no statistical differences were encountered
3 weeks after the procedure. Conclusions: Sequential FLEx
appears to be as safe, effective and stable a refractive procedure
as LASIK in the short term. Larger sample and longer follow-up
are required.
Predictability of Nanojoule Femtosecond Laser Flap
Thicknesses Measured With Corneal Waveform
Ultrasound Technology
Presenting Author: Paul J Dougherty MD
Purpose: To assess the predictability of nanojoule femtosecond
laser (Ziemer LDV) flap thicknesses measured directly with corneal waveform ultrasound technology (Micromedical Devices
P2000). Methods: A prospective study of femtosecond flap
thicknesses directly measured with corneal wavefront technology of 31 eyes of 16 patients undergoing LASIK or presbyopic
corneal implant (Presbylens) was performed. Results: Of the 24
eyes of expected flap thickness of 110 μm, the 4 eyes with 140
μm expected and the 3 eyes with 170 μm expected, the mean
thickness was 105.0 ± 4.9 μm, 135.5 ± 3.7 μm, 164.7 ± 6.1
μm, respectively. Conclusion: Flap thicknesses created with a
nanojoule femtosecond laser and directly measured with corneal
waveform ultrasound technology are highly predictable.
96
Comparison of Recovery of Central Corneal
Sensation After ReLEx Small-Incision Lenticule
Extraction and LASIK
Presenting Author: Dan Z Reinstein MD
Coauthors: Timothy J Archer MA, Marine Gobbe PhD
Purpose: To longitudinally evaluate the recovery of central corneal sensation after small-incision lenticule extraction (ReLEx
SMILE) and compare this to data from published studies after
LASIK. Methods: A retrospective noncomparative case series
included 39 myopic eyes of 20 consecutive patients treated with
ReLEx SMILE using the VisuMax femtosecond laser (Carl
Zeiss Meditec). Central corneal sensation was measured using a
Cochet-Bonnet aesthesiometer before and 1 day and 1, 3, and 6
months after the procedure. A literature search was performed to
find published studies reporting central corneal sensation using a
Cochet-Bonnet aesthesiometer before and after LASIK. The data
from these studies were averaged and used as a comparison for
the ReLEx SMILE population. Results: Mean maximum myopic
meridian treated was -6.70 ± 2.29 D (range: -2.75 to -10.95 D).
Median age was 36 years (range: 19 to 52 years). After ReLEx
SMILE, central corneal sensation dropped from 53 mm preoperatively to 27 mm on Day 1, rising to 39 mm at 1 month, 51 mm
at 3 months, and 50 mm at 6 months. Nine studies were identified that reported central corneal sensation after LASIK, and the
data were averaged at each time point; the central corneal sensation dropped from 58 mm preoperatively to 0 mm at Day 1,
rising to 28 mm at 1 month, 36 mm at 3 months, and 46 mm at
6 months. Across the LASIK studies, the mean spherical equivalent refraction treated was -5.30 D and mean age was 35 years.
Conclusion: There was less reduction in central corneal sensation after ReLEx SMILE than after LASIK at all time points, and
recovery to normal levels was reached by 3 months after ReLEx
SMILE compared with 6 months after LASIK.
Small-Incision Lenticule Extraction Procedure for the
Correction of Myopia and Astigmatism: Six-Month
Results
Presenting Author: Arturo J Ramirez-Miranda MD
Coauthors: Alejandro Navas MD, Tito Ramirez-Luquin MD,
Enrique O Graue-Hernandez MD
Purpose: To report the visual refractive and clinical outcomes
of 60 eyes treated with femtosecond-only small-incision lenticule extraction to correct myopic refractive errors. Methods:
A refractive lenticule of intrastromal corneal tissue was cut
utilizing the VisuMax femtosecond laser system (Carl Zeiss
Meditec; Germany). Simultaneously a small pocket incision was
created. Thereafter, the lenticule was manually dissected with a
Shanzu dissector and removed from the stroma through a 3.5- to
5.2-mm incision using 0.12 forceps. Outcome measures were
corrected distance visual acuity (CDVA), uncorrected distance
visual acuity (UDVA), and manifest refraction during 6 months
of follow-up. Corneal tomography/OCT was also measured.
Results: The study enrolled 60 eyes of 62 patients. Preoperative
mean spherical equivalent was -5.37 D, 3.27 standard deviation
(SD) preoperatively and spherical equivalent +0.17 D, 0.45 SD 6
months postoperatively. Refractive stability was achieved within
6 weeks. Six months after surgery, 84% of all cases had a UDVA
of 20/25 or better. The 6-month postoperative CDVA was the
same as or better than the preoperative CDVA in all the eyes. No
eyes lost lines of CDVA. Conclusions: Small-incision lenticule
extraction (SMILE), a femto-only flapless minimally invasive
technique, appears to be a safe, predictable, and effective procedure to treat myopia and myopic astigmatism.
Small-Incision Lenticule Extraction for Myopia in
1000 Eyes: Predictors for Reproducibility, Efficacy,
and Safety
Presenting Author: Jesper Hjortdal MD
Coauthors: Sven Asp MD, Anders Ivarsen MD, Suganiah
Ketharanathan
Purpose: By small-incision lenticule extraction (ReLEx SMILE)
an intrastromal lenticule is cut with a femtosecond laser and
extracted through a peripheral corneal tunnel. We have investigated whether attempted correction, patient age, sex, corneal
curvature and thickness influence the reproducibility, efficacy,
and safety. Methods: Since January 2011, 1022 ReLEx SMILE
procedures were performed. UCVA, corrected distance visual
acuity (CDVA), and best spectacle refraction were measured
before and 3 months after surgery. Multiple linear regression
analysis was used to identify influence of patient and ocular
outcome predictors. Results: Preoperative spherical equivalent
refraction was -7.30 ± 1.71 D and 3 months after surgery it was
-0.27 ± 0.49 D. Seventeen percent lost 1 or 2 lines of CDVA,
and 35% gained 1 or 2 lines. Three months after surgery, 77%
had from 1 line less to better postoperative UCVA, compared
with CDVA before surgery. Multiple linear regression analysis
showed a 6% undercorrection (P < .01) and an undercorrection
of 0.1 D per decade of increasing age (P < .01). Corneal thickness
and power had no influence. None of the parameters affected
safety and efficacy. Conclusions: Small-incision lenticule extraction for myopia was found reproducible, safe, and effective for
treatment of moderate and high myopia. The present nomogram
results in a 6% undercorrection of intended spherical equivalent
correction. With increasing patient age an undercorrection of 0.1
D per decade was observed. Patient age and intended refractive
change, corneal shape and thickness had no influence on the efficacy or safety of the procedure.
A Prospective Comparison of Wavefront-Guided vs.
Wavefront-Optimized LASIK Clinical Outcomes
Presenting Author: Edward E Manche MD
Purpose: To prospectively compare outcomes between wavefront-guided LASIK and wavefront-optimized LASIK in the
treatment of myopia. Outcome measures include high contrast
Snellen acuity, low contrast Snellen acuity (25% and 5%), safety,
efficacy, predictability, and higher-order aberration analysis.
Methods: A total of 182 eyes of 91 consecutive patients were
treated with wavefront-guided and wavefront-optimized LASIK
in two separate clinical trials. In the first trial one eye was treated
with wavefront-guided LASIK using the AMO CustomVue
STAR S4IR excimer laser and the fellow eye was treated with
wavefront-optimized LASIK using the Alcon Allegretto Wave
Eye-Q 400 Hz excimer laser. In the second trial, both eyes were
treated with the Alcon Allegretto Wave Eye-Q 400 Hz excimer
laser system where one eye was treated with wavefront-guided
LASIK and the fellow eye was treated with wavefront-optimized
LASIK. Eyes were randomized according to ocular dominance
in both studies. Results: At postop Month 12, 84% of eyes in
the CustomVue wavefront-guided group and 76% of eyes in the
Allegretto wavefront-optimized group were within 0.50 D of the
intended correction in the first trial. At postop Month 12, 94%
of eye in the Allegretto wavefront-guided group and 88% of eyes
in the Allegretto wavefront-optimized group were within 0.50
D of the intended correction in the second trial. Conclusions:
Wavefront-guided LASIK had better predictability, better UCVA
results, better low contrast (5%) visual acuity results, and less
induced total higher-order aberrations compared to wavefrontoptimized LASIK in both studies. There were no differences in
safety between the two groups.
97
98
Point: Limbal Relaxing Incisions
Louis D “Skip” Nichamin MD
The decision to use incisional surgery to correct pre-existing
astigmatism, versus insertion of a toric IOL, ought to be based
upon a surgeon’s given comfort level with each of the respective
techniques, along with the specifics of the particular case and
clinical situation.
My own use of astigmatic keratotomy in conjunction with
cataract surgery began in 1989 and subsequently evolved to the
use of limbal relaxing incisions (LRIs) in the mid-1990s. Given
my experience with this technique, it remains my preferred
choice to address astigmatism at the time of implant surgery
except in two circumstances: either the existing astigmatism is
beyond the level that I consider treatable through an incisional
approach alone, or there exists a contraindication to the use of
LRIs.
Based upon the patient’s age, I find that I am able to safely
and reproducibly correct up to 3 D of astigmatism through the
use of LRIs. For levels greater than this, my preference is to
combine the use of both modalities. As such, up to 6 D of astigmatism may be corrected with a toric implant and maximal (90
degree) peripheral intralimbal relaxing incisions. I have on several occasions combined the use of LRI, toric IOL, and excimer
laser (bioptics) to successfully manage congenital astigmatism of
over 9 D!
The other indication for a toric IOL, in my practice, would be
a situation wherein use of an LRI is contraindicated. This would
include eyes that have previously undergone radial keratotomy
wherein further incisional surgery may lead to corneal instability.
Additional contraindications would include keratoconus or other
topographic abnormalities, or known peripheral corneal disease.
One should also be circumspect when dealing with patients
who suffer with advanced autoimmune or rheumatoid disease
that might predispose to healing problems following use of such
peripheral corneal incisions.
As a final caveat, I believe that we all will become increasingly
dependent upon the excimer laser to reduce residual astigmatism
following “successful” implant surgery, including eyes that have
received LRIs or toric IOLs. Our current goal is to leave patients
with less than 0.75 D of cylinder; my prediction is that the bar
will soon be raised to a level of ±0.25 D, for both sphere and
cylinder, and we will therefore be “enhancing” an increasing
proportion of our patients. Let us be prepared!
Counterpoint: Toric IOLs
I. Role of Astigmatism Correction in Cataract Surgery
II. History of Toric IOLs
III. Role in Aberrated Corneas
IV. Advantages Over Limbal Relaxing Incisions
A.Precision
B.Stability
C. Visual acuity
V. Basic Approach to Treatment With Toric IOLs
VI. Complications and Postoperative Management
99
100
Point: Suturing a Posterior Chamber IOL Is the
Way to Go
Walter J Stark MD
Inadequate capsule support is a rare but potential complication associated with cataract surgery. Options include leaving
the patient aphakic, placing an anterior chamber (AC) IOL, or
suture-fixating a 3-piece foldable acrylic IOL in the ciliary sulcus
or the peripheral iris. We now prefer suturing the IOL to the
peripheral iris using a modified McCannel technique.1-3
The technique can be accomplished through a 3.5-mm central
incision. The pupil is constricted with acetylcholine to facilitate
papillary capture of the IOL optic. The IOL is folded in a “moustache fold” and inserted through the corneal wound, placing
the haptics within the sulcus and positioning the optic above
the plane of the iris (see Figure 1). A Barraquer sweep is passed
through the paracentesis and placed beneath the optic as the lens
is unfolded. Additional viscoelastic material is injected into the
AC, pushing the iris posteriorly against the haptics. The Barraquer sweep is used to elevate the optic. Both maneuvers facilitate
visualization of the haptics, simplifying passage of the sutures.
Figure 1C.
Figure 1A.
Figure 1D.
Figure 1B.
Figure 1E.
Figure 2.
Figure 1F.
Figure 3.
Using a modified McCannel-type iris-fixation technique,
a 10-0 polypropylene (Prolene) suture is passed on a needle
(Ethicon CTC-6) through clear cornea and the iris, under the
peripheral aspect of the inferior haptic, then out through the iris
and clear cornea (see Figure 2). A paracentesis is created over the
inferior haptic, and two ends of the suture are pulled through
this site (see Figure 3). The superior haptic is secured in a similar
manner. The sutures are loosely tied with a single throw (see Figure 4) and are not locked. The optic is placed posterior to the iris.
Using a Sinskey hook, the iris is manipulated to produce a round
pupil (see Figure 5). Miochol is injected again to ensure a round
miotic pupil (see Figures 6-7). The sutures are securely tied.
Figure 4.
101
102
Figure 5.
If there is no capsular support, the sutures are tied tight before
the optic is placed in the posterior chamber. If necessary, a vitrectomy through a pars plana incision or an anterior vitrectomy
through the corneal wound is performed. The retained viscoelastic material is removed from the AC.
Air is injected into the AC and checked for unidentified
strands of vitreous. If vitreous is present, a Barraquer sweep is
used to break the strands or a more extensive vitrectomy is performed. Then, a repeat injection of air is made into the AC, again
inspecting for vitreous. A balanced salt solution is injected into
the AC, bringing the eye to a more normal physiologic pressure.
The wound is tested for leaks.
The ability to insert and suture-fixate an IOL through a
3.5-mm incision gives the surgeon greater flexibility in treating
patients with no capsule support. This technique permits secondary IOL insertion in aphakic patients who are contact lens intolerant, facilitates the management of postsurgical IOL problems
that require IOL exchange, and allows the surgeon to properly
treat patients who develop loss of capsule support at the time of
cataract surgery.
References
1. McCannel MA. A retrievable suture idea for anterior uveal problems. Ophthalmic Surg. 1976; 7(2):98-103.
2. Stark WJ, Michels RG, Bruner WE. Management of posteriorly dislocated intraocular lenses. Ophthalmic Surg. 1980; 11:495-497.
3. Stark WJ, Goodman G, Goodman D, Gottsch J. Posterior chamber
intraocular lens implantation in the absence of posterior capsular
support. Ophthalmic Surg. 1988; 19:240-243.
4. Stutzman RD, Stark WJ. Surgical technique for suture fixation of an
acrylic intraocular lens in the absence of capsule support. J Cataract
Refract Surg. 2003; 29:1658-1662.
Figure 6.
Figure 7.
103
Counterpoint: Gluing a Posterior Chamber IOL Is the
Way to Go
Sadeer B Hannush MD
Technique developed by Amar Agarwal MD has evolved in the
last 3 years.
D. Anterior vitrectomy via pars plana, if indicated
E. Two sclerotomies with a 20-gauge MVR blade
under the scleral flaps, 1.0-1.5 mm posterior to the
limbus
F. Prepare corneal incision for injectable 3-piece foldable IOL
G. While IOL is introduced into the anterior chamber
with one hand, introduce a forceps (MST) through
the opposite sclerotomy to grasp the haptic and
externalize it. Grab and externalize the contralateral
haptic using the handshake technique.
H. Centration is important, specially if using multifocal
lens.
I. Inject reconstituted fibrin sealant under the scleral
flaps and to close conjunctival peritomies
J. Close the corneal incisions with 10-0 nylon or with
fibrin sealant.
K. Remove anterior chamber maintainer or pars plana
infusion cannula.
✰ The procedure may be combined with endothelial
keratoplasty.
I.Advantages
A. Small self-sealing incision when using a foldable
IOL
B. Well-formed globe throughout surgical case
C. Less risk of iris prolapse
D. No need for sutures. Avoids suture-related complications: extrusion, cheese-wiring, breakage
E. Less chance of choroidal hemorrhage
F. Avoid complications of larger surgical wounds such
as leakage, shallow anterior chamber or astigmatism
II.Disadvantages
A. Requires surgical expertise to inject the lens through
the surgical incision and avoid dropping the lens
into the vitreous cavity. The surgeon should be
familiar with the handshake technique, which
includes injecting the lens with one hand and grabbing the haptic to exteriorize it through a sclerotomy using the other hand, then delivering the trailing haptic into the eye and exteriorizing it through
the other sclerotomy.
B. After exteriorizing the haptic, the surgeon should
also be familiar with the use of fibrin sealant under
scleral flaps.
III.Procedure
A. Two peritomies, 180 degrees apart, usually in the
vertical hemimeridians
B. Pars plana infusion cannula or anterior chamber
maintainer
C. Create 2 partial-thickness limbal-based scleral flaps
(3.0 x 3.0 mm) at peritomy sites.
IV.Complications
Rare complications include hyphema, decentration,
optic capture and haptic disinsertion.
V.Conclusion
Glued IOLs are a novel approach for PC IOL implantation in the absence of adequate capsular support . The
procedure nicely compartmentalizes the eye into anterior and posterior segments, and it avoids complications related to sutures, large incisions, and hypotony.
104
Counterpoint: Anterior Chamber IOL Is the
Way to Go
Camille J R Budo MD
In 1978 Worst developed the iris claw lens in Pakistan to be
implanted after intracapsular cataract extraction. This anterior
chamber lens is fixated on the iris, leaving the chamber angle
free. The diametrically opposed haptics can be “pinched” on the
midstromal iris tissue as “claws.” In this way the lens stays fixated on the immobile part of the iris.
In 1987 Worst and Fechner developed a phakic anterior
chamber lens for the treatment of high myopia based on the
original iris claw lens. This new lens had a biconcave optic and
the same fixation mechanism as the original iris claw lens. Several hundreds of these lenses were implanted with good refractive
results. However, some reports described corneal endothelial
damage. In 1991, the design of the optic was changed into a convex-concave shape. The main advantage of the new iris-fixation
(myopia) phakic IOL (P-IOL) is the reduction of the height of the
optical rim to lower the chance of intermittent endothelial touch.
In 1997, a plus-powered convex-concave lens was introduced to
correct phakic hyperopia and a P-IOL for the correction of astigmatism was added in 1999. Finally at the beginning of 2002, the
first flexible iris-fixation lens was implanted to correct myopia
and in 2006 for astigmatism.
Crucial to success with any phakic IOL is careful patient
selection. The surgeon should adhere strictly to the following
inclusion criteria when selecting patients for iris-fixation P-IOL:
flat iris, endothelial cell count of at least 2100 cell/mm², pupil
diameter smaller than 6.0 mm, anterior chamber depths of a
minimum of 2.8 mm, peripheral distance from endothelium
to IOL greater than 1.37 mm, internal diameter (the distance
between the 2 iridocorneal angles along the horizontal corneal
diameter [3 to 9 o’clock]) greater than 11.5 mm, and crystalline
lens rise less than 0.6 mm.
We use the Visante OCT (Carl Zeiss Meditec; Jena, Germany)
to ensure that these criteria are respected. It is important to use
an instrument such as the Visante OCT, rather than conventional
ultrasound biometry, because ultrasound can overestimate anterior chamber depth in patients with thick corneas. Additionally,
the Visante OCT can also be used to assess the movement and
position of the iris, which is also important in patient selection.
The power of the P-IOL is calculated using the Van der
Heijde formula, which uses the mean corneal curvature (K),
adjusted anterior chamber depth (ACD−0.8 mm), and spherical
equivalent (SE) of the patient’s spectacle correction at a 12.0-mm
vertex.
The surgical procedure starts with a 2-plane 6.3-mm corneoscleral incision that is centered at 12 o’clock. Two paracenteses
are placed at 2 and 10 o’clock and directed toward the enclavation sites. Miosis is achieved through preoperative instillation of
pilocarpine and a perioperative intracameral injection of acetylcholine 1.0% to prepare the iris for P-IOL fixation, to reduce the
risk of lens-touch during implantation and to facilitate centration of the P-IOL. A cohesive viscoelastic substance is inserted
through the paracenteses and primary incision to maintain sufficient anterior chamber depth, to protect the endothelium, and
to facilitate adjusting the P-IOL within the eye during fixation.
The P-IOL is introduced into the anterior chamber with a Budo
forceps. After subtle rotation of the P-IOL, it is fixated in the
horizontal axis to the midperipheral iris stroma with the use of a
disposable enclavation needle, creating a bridge over the optical
axis. A slit iridotomy is performed at 12 o’clock to avoid pupillary block glaucoma. The viscoelastic substance is exchanged for
balanced salt solution, and Cefuroxime is injected into the anterior chamber at the end of the procedure. The wound is sutured
with 3 to 5 interrupted or 1 uninterrupted 10-0 nylon sutures.
The short-term results of Artisan P-IOL implantation have
been demonstrated in several clinical reports with a follow-up
time of up to 4 years. These reports demonstrate that stabilization of the postoperative refraction occurs within the first few
years after surgery, with more than 90% of eyes achieving a
refraction within 1 D of the intended correction and a high safety
index. The long-term data demonstrated in our study show comparable results. Ten years after Artisan P-IOL implantation for
the correction of moderate to high myopia, the mean SE (±SD)
was -0.70 ± 1.00 D (range: -4.00 to 2.00 D) and remained stable
over time. This finding is in accordance with the short-term literature, which demonstrated stabilization of the postoperative
refraction within the first few years after surgery.
As a consequent and logical evolutionary step forward in irisfixated P-IOL technology, the Artiflex with a foldable lens body,
permitting a small incision, and PMMA haptics was developed
and first implanted to correct myopia in 2002 and for astigmatism in 2006.
The lens power calculation is identical and the surgical procedure is similar to the implantation of the rigid iris-fixation IOL,
with the most important differences being the size of the main
incision and the subconjunctival injection of methylprednisolone
(acetate) to avoid any reaction to the silicone material.
The Artiflex study shows long-term results that are generally
comparable with those of previous Artisan studies. Although
nonpigment and pigment precipitates have been found on Artisan P-IOLs in some cases, it seems that the occurrence of pigment
precipitates is higher with the Artiflex lens. The incidence of
pigment precipitates was highest at the 3-month postoperative
examination. In most cases, the precipitates were transient. Several investigators treated the pigment precipitates with mydriatic
eye drops or corticosteroids, after which the precipitates disappeared or stabilized without clinically significant consequences.
In cases where the investigator chose not to give medication, the
precipitates disappeared after 1 year. At 2 years after surgery, the
incidence of pigment precipitates was 4.8% and none of the eyes
had a loss of visual acuity.
The multicenter study has been set up to see if the Artiflex
lens can live up to the clinical standards set by the well-established Artisan lenses. The study results show that the Artiflex
P-IOL is a very useful extension of the Artisan product family.
Excellent results with predictability and efficacy can be obtained
when good patient selection, a correct surgical technique, and
sufficient postoperative care according to the specifications of the
manufacturer are taken into account.
Point: Phaco
Uday Devgan MD
N ot e s
105
106
Counterpoint: Small-Incision Manual Cataract Surgery
I. Challenges of Hard Brown Cataract
A. Often older patient with comorbid diseases; higher
incidence of complications
1. Higher risk of capsular tear
2. Risk of choroidal hemorrhage
3. Weaker zonules
B. Longer ultrasound times; more corneal damage
C. Poor visualization
II. Manual ECCE: Technique
1. Bridal or no bridal suture
2. Location of incision: limbal vs. tunneled incision
3. Capsule opening
4. Lens extraction
5. Cortex removal
6. Lens and haptic placements
7. Suturing tips
1. Lens sectioning techniques
2. Irrigating lens loop
3. International techniques
III. Outcomes of Small-Incision Manual ECCE
A. Average times for phaco vs. manual surgery
B.Cost
C. Himalayan Eye Study With Change/Ruit
A. Large incision
B. Small incision
IV. So Why Recommend Phaco Over Manual?
A. New Technology
B. Bias toward expensive procedure being “better”
V.Recommendations
Point: Accommodating IOL
R Bruce Wallace MD
Refractive cataract surgeons now have a number of IOLs available to help patients achieve the desired result of less spectacle
dependency.
Numerous clinical studies and FDA trials have demonstrated
the remarkable visual results with all the technologies that are
available. When comparing the quality of near uncorrected
vision for the patients with a plano refraction, multifocal IOLs
have shown advantages over the Crystalens. However, unwanted
side effects, such as nighttime halos, have been shown to be less
significant with the Crystalens. What has not been regularly measured in these studies is the quality of postoperative uncorrected
intermediate vision.
Lately, we have seen a shift in add powers for the Alcon
ReSTOR and the AMO Tecnis multifocal IOLs to lower powers.
Why? Because intermediate vision is important to our patients.
Computers, dashboards, mirrors, desk work and just everyday facial encounters with friends and family bring out the value
of clear uncorrected intermediate vision. Fortunately, visual cortical adaptation after multifocal IOL implantation can provide
some improvement in this area over time. However, accommodative IOLs, like the Crystalens, continue to offer more consistent, clearer intermediate vision soon after surgery. Many IOL
companies are actively designing accommodative alternatives to
diffractive multifocals because of the importance of better intermediate vision.
This presentation is designed to provide information to help
refractive cataract surgeons provide better options for better
intermediate vision for their patients while introducing less
potential for glow and halo, especially with nighttime driving.
107
108
Counterpoint: Multifocal IOL
Terry Kim MD, Jay Meyer MD
I. What is the goal of presbyopia-correcting IOLs?
A. Spectacle independence
B. Good acuity at distance, intermediate, near
VII. Multifocal vs. Accommodating IOL Studies
II. There is no perfect presbyopia-correcting IOL to meet
the needs of all patients. So what is the best presbyopiacorrecting IOL for most patients?
C. Few studies comparing multifocal to accommodating IOLs
A. Lane SS. Visual acuity with spectacle wear with
presbyopia-correcting intraocular lenses.14
1. Prospective, subject-masked, multicenter study,
randomized to receive either bilateral apodized
diffractive IOL (IQ ReSTOR +3.0 D, model
SN6AD1; Alcon; n = 33), or bilateral accommodative IOL (Crystalens HD; Bausch + Lomb; n =
27).
2. Results at 3 months postoperative indicated
mean binocular distance-corrected near visual
acuity:
In 2012, the best option for most patients who desire a
presbyopia-correcting IOL for spectacle independence
is a multifocal IOL.
III. Multifocal IOL Advantages
A. Good near vision and improved intermediate acuity1-3
B. Spectacle independence1
C. Predictable and accurate refractive outcomes1,2
D. Depth of field
E. Easy implantation
F. Long-term capsular bag stability
G. With neuroadaptation, symptoms of glare and
haloes improve.4
IV. Multifocal IOL Disadvantages
A. Potentially limited intermediate vision3,5
B. Reduced contrast sensitivity compared to accommodating and monofocal lenses6
C. Pupil size and centration dependent7
D. Potentially reduced color perception8
E. Glare and haloes9
F. Unhappy patients may require explantation of IOL.
A. Higher rating of vision without spectacles compared
to monofocal lens10
B. In several studies, over 90% of patients would
choose to have the same IOL implanted again.2,10,11
C. For dissatisfied patients, the cause can be identified and effective treatment measures taken in most
cases. Few eyes require IOL exchange (4%-7%).12,13
VI. Issues With Current Available Studies
A. Lack of standardization of testing reading acuity,
reading speed, duration of reading, depth of focus,
quality of vision, spectacle dependence
B. Several different quality-of-life and quality-of-vision
questionnaires
a. At 40 cm, was ~3 Snellen lines better with IQ
ReSTOR IOL than with Crystalens
b. At preferred near distance, was ~1.5 Snellen
lines better with IQ ReSTOR IOL than with
Crystalens
c. Was located at a preferred near distance that
was farther out from the eye with Crystalens
(~51 cm) than with IQ ReSTOR IOL(~38 cm)
3. Spherical equivalent was more predictable with
IQ ReSTOR IOL than with Crystalens.
4. Spectacle independence rates were higher with
IQ ReSTOR IOL (83% of patients) than with
Crystalens (38% of patients).
V. Patient Satisfaction With Multifocal IOLs
B. Pepose JS, et al. Visual performance of patients with
bilateral vs combination Crystalens, ReZoom, and
ReSTOR intraocular lens implants.15 Prospective,
nonrandomized.
1. Crystalens was better for intermediate vision.
2. ReSTOR was better for near vision.
3. Multifocal IOL was associated with lower contrast sensitivity and higher photic phenomena.
VIII. Accommodating IOL Disadvantages
A. Less predictable spherical equivalent
B. Possible change in refraction after YAG capsulotomy
C. Capsular changes over time
D. Possible need for reading glasses (less spectacle independence)
E. May not provide enough accommodation for comfortable sustained reading without resultant asthenopia
IX.Summary
Multifocal IOLs offer patients an option for good
uncorrected distance, intermediate, and near vision.
A high percentage of patients achieve spectacle independence and would choose to have the same IOL
implanted again. Compared to accommodative IOLs,
reduced contrast sensitivity may limit multifocal IOL
use in some patients who perform low light activities.
Glare and haloes can improve over time and may be
less prevalent with newer aspheric lenses.
References
1. Kohnen T, Nuijts R, Levy P, et al. Visual function after bilateral
implantation of apodized diffractive aspheric multifocal intraocular lenses with a +3.0 D addition. J Cataract Refract Surg. 2009;
35:2062-2069.
2. Lane SS, Javitt JC, Nethery DA, et al. Improvements in patient
reported outcomes and visual acuity after bilateral implantation of
multifocal intraocular lenses with +3.0 diopter addition: multicenter
clinical trial. J Cataract Refract Surg. 2010; 36:1887-1896.
109
7. Alfonso JF, Fernández-Vega L, Baamonde MB, Montés-Micó R.
Correlation of pupil size with visual acuity and contrast sensitivity after implantation of an apodized diffractive intraocular lens. J
8. Pieh S, Hanselmayer G, Lackner B, et al. Tritan colour contrast
sensitivity function in refractive multifocal intraocular lenses. Br J
Ophthalmol. 2001; 85:811-815.
9. Palmer AM, Faiña PG, Albelda EA, et al. Visual function with bilateral implantation of monofocal and multifocal intraocular lenses:
a prospective, randomized, controlled clinical trial. J Refract Surg.
2008; 3:257-264.
10. Packer M, Chu YR, Waltz KL, et al. Evaluation of the aspheric Tecnis multifocal intraocular lens: one-year results from the first cohort
of the Food and Drug Administration clinical trial. Am J Ophthalmol. 2010; 149:577-584.
11. Kohnen T, Allen D, Boureau C, et al. European multicenter study
of the AcrySof ReSTOR apodized diffractive intraocular lens. Ophthalmology 2006; 113:584.e1.
12. De Vries NE, Webers CA, Touwslager WR, et al. Dissatisfaction
after implantation of multifocal intraocular lenses. J Cataract
Refract Surg. 2011; 37:859-865.
3. Blaylock JF, Si Z, Vickers C. Visual and refractive status at different
focal distances after implantation of the ReSTOR multifocal intraocular lens. J Cataract Refract Surg. 2006; 32:1464-1473.
13. Woodward MA, Randleman JB, Stulting RD. Dissatisfaction after
multifocal intraocular lens implantation. J Cataract Refract Surg.
2009; 35:992-997.
4. Chang D. Mastering Refractive IOLs: The Art and Science. Thorofare, NJ: SLACK; 2008.
14. Lane SS. Visual acuity with spectacle wear with presbyopia-correcting intraocular lenses. ISRS Poster. October 2010.
5. Hütz WW, Eckhardt HB, Röhrig B, Grolmus R. Intermediate vision
and reading speed with Array, Tecnis, and ReSTOR intraocular
lenses. J Refract Surg. 2008; 24:251-256.
15. Pepose JS, Mujtaba AQ, Davies J, et al. Visual performance of
patients with bilateral vs combination Crystalens, ReZoom, and
ReSTOR intraocular lens implants. Am J Ophthalmol. 2007;
144:347-357.
6. Mesci C, Erbil HH, Olgun A, et al. Differences in contrast sensitivity between monofocal, multifocal and accommodating intraocular
lenses: long-term results. Clin Experiment Ophthalmol. 2010;
38:768-777.
110
Section VII: Lens Complications—Video Presentations
Subluxation and Rings
Thomas A Oetting MD
Figure 1.
Figure 3.
Figure 2.
Figure 4.
Figure 5.
Figure 8.
Figure 6.
Figure 9.
Figure 7.
111
112
Capsular Defects
Iqbal K Ahmed MD
N ot e s
Glued IOL
Roger F Steinert MD
N ot e s
113
114
Lens Nightmare
Amar Agarwal MD
Lens nightmares can be a daunting challenge. Once there is a
problem in lens surgery it becomes very difficult to fix. In this
presentation we will be showing, through videos, the management of such a situation: how the case is handled and treated.
The glued IOL technique helps us to handle challenging nightmares and to help our patients see better.
115
Premium IOL Exchange
Principles
David F Chang MD
Dr. Chang’s consulting fees from AMO and Alcon are donated to Project
Vision and Himalayan Cataract Project. He has no financial interest in
any instruments.
I. Strategies Before Explanting a Multifocal IOL for
Issues of Blur or Visual Aberrations
A. Reassurance and adequate period for neuroadaptation
B. Treatment of residual refractive error: Prior to doing
enhancement, a trial with a contact lens or spectacles can differentiate uncorrected refractive error
from optical aberrations.
1. May be subtle, but present after prior refractive
surgery, with basement membrane disease, marginal thinning, etc.
2. Many topographers have software that can measure corneal HOA
3. Tracey and Nidek OPD are able to measure total
eye HOA and differentiate corneal from lenticular HOA
D. Treat dry eye
E. Rule out maculopathy (eg, OCT)
F. Consider laser pupilloplasty if diffractive optic
poorly centered with pupil
G. If appropriate, implant second eye with monofocal
or accommodating IOL to see if halos/ghosting in
first eye are more tolerable.
H. Avoid posterior YAG capsulotomy if IOL exchange
may be necessary.
1. Clinical history differentiates whether “was
great, and then got cloudy” is consistent with
capsular opacity. “Was bad, starting right after
surgery” is not consistent with the later onset of
posterior capsule opacification (PCO).
II. IOL Exchange Principles
Early is easier, but if overlapping continuous curvilinear capsulorrhexis (CCC) and no cortex, can easily
reopen within 6-8 months.
A. If CCC diameter is small or CCC is partially “off”
the optic and fused to posterior capsule, removal
will be more difficult, and earlier timing of exchange
is better.
1. May need to first lift capsulorrhexis edge off of
an AcrySof lens optic with #30 needle or flat
spatula
2. Use 3 paracentesis sites to expand 3 sectors of
equatorial capsular bag.
3. Intermittently burp out OVD to avoid overfilling
the anterior chamber (AC).
C. Bring optic and haptics into AC. With smaller CCC,
may need “chopstick” maneuver with 2 hooks to
deliver optic through the CCC. Try not to cut CCC
if possible.
D. Microsurgical IOL cutters (eg, MST, Geuder AG)
optimize intraocular control and better avoid
wound gape that will allow OVD to burp out.
The Packer-Chang IOL cutter from MST is strong
enough to cut the rigid Tecnis or ReZoom acrylic
material. Intraocular IOL holding forceps prevent
optic from tilting and migrating as it is being cut.
These can be inserted via a separate paracentesis.
E. Haptic of AcrySof platform has a terminal bulb
that will become fibrosed within the capsular equator after several months. Care must be taken not
to dehisce the zonules by excessive traction on the
haptic. One must be prepared to amputate and leave
behind the haptic in this situation.
F. If posterior capsule has been YAG-ed, expect vitreous loss. Attempt to preserve the anterior capsule
during the vitrectomy, which can allow optic-CCC
capture. Have backup IOLs for non-capsular bag
fixation as a contingency.
C. Rule out higher-order corneal aberrations (HOA)
with wavefront aberrometry.
B. Use dispersive ophthalmic viscosurgical device
(OVD) (eg, Viscoat) to re-expand the capsular bag.
Instrument Information
1.www.microsurgical.com/
2.www.geuder.de/0,1,2
116
Refractive Surprise
Robert H Osher MD
N ot e s
117
Iris Woes
Samuel Masket MD
Congenital and acquired defects of the iris induce both functional and aesthetic deficiencies for patients. The former concerns are generally related to glare disability, often precluding or
limiting driving and other routine activities of daily life. Moreover, for some patients, the cosmetic blemish associated with
iris abnormalities can hamper their lives significantly. Eyes with
iris deficiencies often have comorbidities, some of which may be
addressed concurrent with correcting the iris abnormality. While
some iris defects may be managed with sutures, artificial iris
devices are often required for satisfactory results.
Fortunately, the manufacturing sector offers a number of clinical tools to manage partial and total aniridia, allowing patients
to have improved functional vision and expanded lifestyle. Custom contact lenses designed to match the patient’s residual or
fellow eye iris are available; however, in my experience they have
a low level of success for a number of reasons. Corneal tattooing
may benefit occasional cases with limited iris defects but offers
little to no benefit for the individual with a lightly colored iris.
The majority of aniridic cases benefit mostly from an
implanted iris prosthesis. However, there are no artificial iris
devices that have achieved approval from the USFDA; implantation can occur only under an investigational protocol (IDE) or
by individual compassionate use device exemption (CUDE) from
the FDA.
Presently, my preferred device is the Dr. Schmidt foldable
custom artificial iris (HumanOptics AG; Erlangen, Germany).
It is available with and without a fiber backing; the former is
suggested when the device requires suture fixation to the sclera.
The nonfiber backed model is designed for placement within the
capsule bag.
A representative case is presented. Each case represents
special challenges, but also great opportunity to enhance the
patient’s lifestyle.
Figure 1. Involved LE demonstrates a corneal scar noted at the 9 o’clock
position, marked iris deformity with extensive iridodialysis and loss of
iris tissue; an advanced nuclear cataract is also noted.
At surgery the natural iris remnant was largely excised, the
cataract removed, a capsule tension ring placed, and an IOL and
artificial iris implanted within the capsule bag. For best visual
acuity (20/25), she requires a rigid contact lens, owing to irregular corneal astigmatism induced by the original corneal laceration. She is very pleased with improved vision and cosmesis (see
Figures 2 and 3).
Case Presentation
A 60-year-old woman had sustained penetrating trauma to the
left eye (LE) 30 years earlier. As a consequence of an automobile
accident, she sustained a perforating corneal injury with loss of
iris tissue. Over time a dense cataract ensued. She was referred
for evaluation and management of the iris defect (see Figure 1).
She was highly motivated for surgical correction.
Figure 2. Postoperative slitlamp view of LE demonstrates artificial iris
with an excellent cosmetic result.
118
Figure 3. External photograph illustrates aesthetic results of surgery.
Keynote Lecture
119
Overview of Phakic IOLs
Thomas Kohnen MD PhD FEBO, Oliver K Klaproth Dipl Ing(FH)
Trials comparing corneal refractive surgery with phakic IOLs
(P-IOLs) reveal the superiority of the latter in terms of quality of
vision, while other parameters like stability, safety, and efficacy
are comparable.1,2 However, today P-IOLs are most often used
in patients where refractive corneal surgery is not applicable due
to high ametropia, large pupils, and thin or irregular corneas.
Known severe long-term complications like endothelial cell loss
or cataracts discourage many surgeons from using phakic lenses
as an equal procedure next to laser refractive surgery.3,4
The question arises whether these doubts, resulting from
many failures in the development of different P-IOLs, are still
appropriate when modern P-IOL are used? The answer is yes.
And no. Doubts are justified, but the lessons learned from former
implants are not 100% applicable to today’s lenses.
The most dreaded complication of the posterior chamber
P-IOL is iatrogenic cataract, induced by contact between the
P-IOL and the natural lens due to insufficient vaulting and/
or modified aqueous humor fluidics. Schmidinger et al5 show
a nearly linear and continuous decrease in the distance of the
ICL V4 (Staar) and the natural lens in 84 patients—from 466 ±
218 µm directly after surgery to 184 ± 159 µm after 74.1 ± 23.1
months. The resulting clinically significant anterior subcapsular
cataract rate in their retrospective trial cohort was 28% after 44
months. Seventeen percent of patients underwent explantation
of the P-IOL following cataract surgery. Inadequate clearance
between the natural lens and the P-IOL was a significant predictor for anterior subcapsular cataract formation.
The latest design evaluation of the ICL provides a central
hole in the optic to prevent pupillary blocking and to enhance
the aqueous humor fluidics in the gap between the ICL and the
lens to reduce cataract formation (see Figure 1). First results by
Shimizu et al6 show very good short-term visual results, comparable to other phakic lenses, providing the practicability of the
central hole. Although this is a very promising implant, longer
follow-ups are needed to evaluate the cataract rate and long-term
vaulting stability.
In contrast to this very new posterior chamber P-IOL, the
long-term results of today’s most commonly used anterior chamber iris-fixated P-IOL (Artisan, Ophtec; see Figure 2) are well
known. The visual outcomes are excellent, even in toric patients.
Sizing of the implants is, contrary to the posterior chamber or
angle-supported anterior chamber IOL, not an issue. The weak
point of the iris-fixated P-IOL is endothelial cell loss. Some studies show mean rates of up to 14.05% after 5 years.4 Outliers,
however, also need to be taken into consideration.
A
B
Figure 1. Slit lamp (A) and ultrasound biomicroscopy imaging (B) of the
ICL (Staar) with central hole (“aquaport”). Both images courtesy of Dr.
Aramberri.
120
Keynote Lecture
Figure 2. Iris fixated Artisan lens (Ophtec), 2 years post-implantation.
The history of anterior chamber angle-supported P-IOLs
is mainly a history of failures. Even though visual results have
been very good, severe endothelial cell losses, pupil ovalizations, synechia, and inflammations have led to the withdrawal
of almost every implant.3,4 The latest development in this field is
the Cachet P-IOL (Alcon, see Figure 3), a single-piece, foldable
soft acrylic IOL. Visual results are very good, as published 3-year
FDA trial data by Knorz et al7 show. For example: UDVA was
20/40 or better in 101 patients (97.1%) and 20/20 or better in 48
of 104 patients (46.2%). The residual refractive error was within
±0.50 D of target in 82 patients (78.8%).
Apart from that, all other known severe complications from
angle-supported anterior chamber lenses seem to be under control. No pupil ovalization, pupillary block, or retinal detachment
was observed after 3 years.7 Looking particularly at the endothelial cell loss data leaves refractive surgeons optimistic. The
annualized percentage loss in central and peripheral endothelial
cell density from 6 months to 3 years was 0.41% and 1.11%,
respectively.7,8 The natural endothelial cell loss in adults is about
0.3% to 0.6%. Both visual acuity and endothelial cell loss numbers remain stable when looking at the, yet unpublished, 5-year
follow-up. However, longer follow-up is required here as well, to
evaluate the long-term safety.
The ideal phakic lens has to fulfill different requirements.
Lenses should be foldable to allow for astigmatism-neutral
implantation and thus predictable refractive outcome. Lens
design, positioning, and material should not induce any short- or
long-term intraocular damage; endothelial cell loss and cataract
formation are especially an issue here. If lenses fulfill these needs,
there is no reason why P-IOLs should not be used as an equal
procedure next to corneal laser refractive surgery. Eventually
P-IOLs have one major advantage compared to excimer laser
surgery: their reversibility!
References
1. Vilaseca M, Padilla A, Pujol J, Ondategui JC, Artal P, Guell JL.
Optical quality one month after Verisyse and Veriflex phakic IOL
implantation and Zeiss MEL 80 LASIK for myopia from 5.00 to
16.50 diopters. J Refract Surg. 2009; 25:689-698.
2. Barsam A, Allan BD. Excimer laser refractive surgery versus phakic
intraocular lenses for the correction of moderate to high myopia.
Cochrane Database Syst Rev. 2010:CD007679.
3. Guell JL, Morral M, Kook D, Kohnen T. Phakic intraocular lenses
part 1: historical overview, current models, selection criteria, and
surgical techniques. J Cataract Refract Surg. 2010; 36:1976-1993.
4. Kohnen T, Kook D, Morral M, Guell JL. Phakic intraocular lenses:
2. Results and complications. J Cataract Refract Surg. 2010;
36:2168-2194.
5. Schmidinger G, Lackner B, Pieh S, Skorpik C. Long-term changes
in posterior chamber phakic intraocular collamer lens vaulting in
myopic patients. Ophthalmology 2010; 117:1506-1511.
6. Shimizu K, Kamiya K, Igarashi A, Shiratani T. Early clinical outcomes of implantation of posterior chamber phakic intraocular lens
with a central hole (hole ICL) for moderate to high myopia. Br J
Ophthalmol. 2012; 96(3):409-412.
Figure 3. Cachet phakic angle supported lens (Alcon).
7. Knorz MC, Lane SS, Holland SP. Angle-supported phakic intraocular lens for correction of moderate to high myopia: three-year
interim results in international multicenter studies. J Cataract
Refract Surg. 2011; 37:469-480.
8. Kohnen T, Knorz MC, Cochener B, et al. AcrySof phakic anglesupported intraocular lens for the correction of moderate-to-high
myopia: one-year results of a multicenter European study. Ophthalmology 2009; 116:1314-1321.
Section VIII: The Journal of Refractive Surgery’s Hot, Hotter, Hottest
121
Short-term Cell Death and Inflammation After
Intracorneal Inlay Implantation in Rabbits
Marcony R Santhiago MD PhD, Flavia L Barbosa PhD, Vandana Agrawal MD, Perry S Binder MD, Bruce
Christie MD, Steve E Wilson MD
Introduction
Several surgical approaches have been proposed to treat presbyopia, including intrastromal insertion of corneal inlays. Barraquer performed early experiments with corneal implants in
1949.1 Intrastromal corneal inlays have recently been designed
for treatment of presbyopia due to potential reversibility, ease of
implantation and repositioning, and possible combination with
other refractive procedures to allow for simultaneous correction
of ametropias.
Prior studies of experimental intracorneal implants were
plagued by complications such as corneal opacification, vascularization and necrosis, along with problems related to decentration.2-6 The development of materials with enhanced biocompatibility7,8 and advances in technology, such as femtosecond
lasers, that facilitate the reliable creation of stromal pockets and,
therefore, better centration of implants have made this approach
more attractive.9-12
The mechanisms behind the current generation of inlays
designed for treatment of presbyopia can be divided into three
categories: (1) small-aperture corneal inlays, (2) space-occupying
inlays that create a hyperprolate cornea, and (3) refractive annular addition lenticules that work as a bifocal optical inlays separating distance and near focal points.9
The AcuFocus Kamra Inlay (AcuFocus, Inc.; Irvine, Calif.,
USA) is based on the concept of small-aperture optics, where
light rays pass through a small aperture and thereby increase
the eye’s depth of focus. Thus this technology uses the principle
of the pinhole effect to increase depth of field and minimize the
effects of refractive error. The clinical studies published thus far
have demonstrated that the AcuFocus Kamra inlay (ACI 7000)
effectively improves near vision and reading speed in patients
with presbyopia.9-12 However, the biological effects of this modern intrastromal implant on the cornea remain unclear. The purpose of this animal study was to investigate the corneal inflammatory and cell death response to femtosecond pocket creation
and intrastromal implantation of the Kamra inlay at different
time points after surgery in the rabbit model.
Methods
Twenty-four rabbits were included in the study. Each rabbit had
pockets generated in both corneas with a femtosecond laser. One
eye of each rabbit had an inlay inserted into the pocket, and the
opposite control eye had the pocket dissected. Eight rabbits were
studied at 24 hours, 48 hours, or 6 weeks after surgery. Tissue
sections were analyzed with TUNEL assay to detect cell death
and immunohistochemistry for CD11b to detect monocytes as a
marker for inflammation.
Results
The inlay group had significantly more stromal cell death than
the control group at 48 hours after surgery (P = .038). At 24
hours and at 6 weeks after surgery there was no significant difference in stromal cell death between the inlay and control groups.
There were significantly more CD11b+ cells in the stroma in the
inlay group compared to the control group at both 24 and 48
hours after surgery (P = .025 and P = .001, respectively). However, at 6 weeks after surgery, there was no significant difference
in CD11b+ cells between the control and inlay group.
Conclusions
Although there was an early increase in stromal cell death and
inflammation in eyes that had a femtosecond pocket and AcuFocus inlay insertion compared to the control group with the
pocket alone, there was no significant difference between the
inlay and control group in stromal cell death or inflammation at
6 weeks after surgery.
References
1. Barraquer JI. Queratoplatica refractiva. Estudios e informaciones
oftalmologicas. 1949; 2:10.
2. Deg JK, Binder PS. Histopathology and clinical behavior of polysulfone intracorneal implants in the baboon model. Polysulfone lens
implants. Ophthalmology 1988; 95:506-515.
3. Alió JL, Mulet ME, Zapata LF, Vidal MT, De Rojas V, Javaloy J.
Intracorneal inlay complicated by intrastromal epithelial opacification. Arch Ophthalmol. 2004; 122:1441-1446.
4. Lane SL, Lindstrom RL, Cameron JD, et al. Polysulfone corneal
lenses. J Cataract Refract Surg. 1986; 12:50-60.
5. Choyce P. The present status of intracorneal implants. Can J Ophthalmol. 1968; 3:295-311.
6. Dohlman CH, Refojo MF, Rose J. Synthetic polymers in corneal
surgery: glyceryl methacylate. Arch Ophthalmol. 1967; 177:52-58.
7. Sweeney DF, Vannas A, Hughes TC, et al. Synthetic corneal inlays.
Clin Exp Optom. 2008; 91:56-66.
8. Laroche G, Marois Y, Guidoin R, et al. Polyvinylidene fluoride
(PVDF) as a biomaterial: from polymeric raw material to monofilament vascular suture. J Biomed Mater Res. 1995; 29:1525-1536.
9. Waring GO IV, Klyce SD. Corneal inlays for the treatment of presbyopia. Int Ophthalmol Clin. 2011; 51:51-62.
10. Yilmaz OF, Bayraktar S, Agca A, Yilmaz B, McDonald MB, van de
Pol C. Intracorneal inlay for the surgical correction of presbyopia. J
11. Seyeddain O, Riha W, Hohensinn M, Nix G, Dexl AK, Grabner
G. Refractive surgical correction of presbyopia with the AcuFocus
small aperture corneal inlay: two-year follow-up. J Refract Surg.
2010; 26:707-715.
12. Dexl AK, Seyeddain O, Riha W, Hohensinn M, Hitzl W, Grabner
G. Reading performance after implantation of a small-aperture
corneal inlay for the surgical correction of presbyopia: two-year
follow-up. J Cataract Refract Surg. 2011; 37:525-531.
122
Update on Therapeutic Bandage Lenses for
Surface Ablation
Marguerite McDonald MD
I.Purpose
IV. Representative Subjective Questions
A. To evaluate vision recovery following PRK with
placement of a Nexis ocular shield
A. If you had to return to work today, would you be
able to?
B. Monocular and binocular visual acuity and subjective questionnaire were used to measure recovery.
B. Are you able to drive?
C. If unable to drive is it due to vision or comfort?
C. WaveLight excimer laser used for treatment
D. Rate your light sensitivity, discomfort, burning, foreign body sensation, tearing, dryness, heaviness of
eyelids.
II. Study Design and Patient Demographics
A. Prospective, historical control
B. 28 patients (55 eyes)
C. Multiple centers
D. Bilateral treatments
E. Age: 23 to 46 years (32.4 + 6.8)
F. Preop SE: +0.50 to -6.75 (-3.26 ± 1.52)
G. Astigmatism: 0 to -2.50 (-0.77 ± 0.66)
H. Gender: 18 M, 30 F (to date)
A. Preop visit, 1 hour*, 1 day, and 2, 3, 4, 5, and 7
days
B. Objective testing at all visits
1. Binocular and monocular uncorrected distance
visual acuity (VA), corrected distance VA
2. Manifest refraction
3. Mesopic contrast sensitivity function (Optec
6500)
4. Optical Quality Assessment System (OQAS)
5. Anterior segment OCT (OptoVue)
6.Orbscan
7. Pentacam (preop only)
A. Preoperative diazepam
B. 7.5-mm epithelial debridement
C. Postoperative medications: antibiotic q.i.d. x 1
week, steroid q.i.d.-b.i.d. x 1 week taper, NSAID
q.i.d. until shield removal, PO pain meds, artificial
tears
III. Visit Schedule
V. Surgical Methods and Technique
VI. Epithelial Healing
A. Superior to standard PRK both in speed of healing
and quality
B. In our last series 60% epithelialized in 2 days, 100%
in 3 days.
VII. Epithelial Quality
A. Epithelial quality is far superior to bandage lens.
B. This important observation will be evaluated in
more detail.
VIII. The NexisVision ocular shield provides:
A. Rapid visual recovery from PRK, comparable to
LASIK
B. Faster epithelial healing than PRK with a standard
bandage lens
C. Improved patient satisfaction compared to PRK
with a standard bandage lens
D. Further study: managing postoperative discomfort
C. Anterior segment photographs
Light-Adjustable IOLs
Arturo S Chayet MD
N ot e s
123
124
Toric IOLs for Keratoconus
Alejandro Navas MD
I. There are several treatments in the management of
patients with keratoconus (KC).1
A.Spectacles
B. Contact lenses
C. Intrastromal ring segments
D. Collagen crosslinking (CXL)
E. Keratoplasty (lamellar, penetrating, femtosecond
laser-assisted)
F. Excimer laser ?
G. Intraocular lenses: in-the-bag, phakic IOLs (pIOLs)
H. Toric IOLs ???
I. Combined treatments
III. Most Important Aspects to Consider With Toric
E. Identifiable axis to properly align the toric IOL
F. Patients with unstable and progressive keratoconus
or unobtainable refraction should be excluded.
IOLs5
IV. IOL Calculation and Surgical Technique
A. Phakic IOLs do not have big issues regarding calculations because they mostly depend on the refraction.
B. Keratometric values obtained by tomography and/
or tomography
C. Interferometry for axial length determination
D. SRK II formula (broader KC range)6
E. Toric calculator software
F. Routine toric IOL phacoemulsification / phacoaspiration (alignment marks emphasis)
A.Age
1. Refractive lens exchange (RLE) should be
avoided in patients younger than 40 years of age.
2. KC patients develop cataracts sooner compared
with the normal population.6
3. With greater age, lower KC progression rates
4. Toric pIOLs could be considered in younger
patients (higher KC progression rates, maybe
combine with CXL or intrastromal rings7)
V.Conclusion
Short-term results are promising3-5 (see Figure 1), but a
few points should be considered:
A. While KC is lower in advanced ages, risk of KC progression “always” persists.
B. Age cut is debatable; most recent consensus about
RLE vs. pIOL8:
1. pIOLs (including toric pIOLs) in younger than
48 years
2. RLE safer in older than 55 years
B. Stability/lack of progression
D. “Not so irregular” astigmatism (regular astigmatism
definition: refractive error that could be corrected
with conventional spectacles)
II. Few studies had been reported using in-the-bag toric
IOLs in keratoconus.2-4
1. At least 1 year of topographic and/or refractive
stability evidence
2. Ideally confirmed forme fruste KC, or KC grades
I and II
C. Mild refraction changes or even refractive surprises
still can be corrected.
D. Reversible (pIOLs) vs. irreversible (pseudophakic
IOL) procedures
E. Lifetime perspectives: Just one procedure (in-thebag) can solve the problem.
C. “Refractability”: Capacity to improve corrected distance VA with phoropter (N/A for cataract patients,
just in RLE)
125
Figure 1.
References
1. Jhanji V, Agarwal T, Sharma N, Vajpayee RB. Management of keratoconus: current scenario. Br J Ophthalmol. 2011; 95:1044-1050.
2. Sauder G, Jonas JB. Treatment of keratoconus by toric foldable
intraocular lenses. Eur J Ophthalmol. 2003; 13:577-579.
3. Navas A, Suárez R. One-year follow-up of toric intraocular lens
implantation in forme fruste keratoconus. J Cataract Refract Surg.
2009; 35:2024-2027.
4. Visser N, Gast ST, Bauer NJ, Nuijts RM. Cataract surgery with
toric intraocular lens implantation in keratoconus: a case report.
Cornea 2011; 30:720-723.
5. Jaimes M, Xacur-García F, Alvarez-Melloni D, Graue-Hernández
EO, Ramirez-Luquín T, Navas A. Refractive lens exchange with
toric intraocular lenses in keratoconus. J Refract Surg. 2011;
27:658-664.
6. Thebpatiphat N, Hammersmith KM, Rapuano CJ, Ayres BD,
Cohen EJ. Cataract surgery in keratoconus. Eye Contact Lens.
2007; 33:242-246.
7. Navas A, Tapia-Herrera G, Jaimes M, et al. Implantable collamer
lenses after intracorneal ring segments for keratoconus. Int Ophthalmol. Epub ahead of print 12 May 2012.
8. Nanavaty MA, Daya SM. Refractive lens exchange versus phakic
intraocular lenses. Curr Opin Ophthalmol. 2012; 23:54-61.
126
Advances in Translational Science in
Refractive Surgery
Farhad Hafezi MD
Introduction
Conclusions
From idea to established treatment: Translational research in
ophthalmology
The famous phrase “from bench to bedside,” which originated in
the 1990s, was often used to illustrate the bridge between basic
science and applied medicine. Retrospectively, this phrase may
have been the beginning stages of what is now known as translational research/medicine.
A current definition states: “Translational research transforms scientific discoveries arising from laboratory, clinical, or
population studies into clinical applications to reduce disease
incidence, morbidity, and mortality.”
This implies utilizing and streamlining high-level basic and
preclinical research concepts and ideas in a timely and efficient
manner. With the realization of these initiatives, many benefits
could result, including increase in job opportunities due to new
companies, research funding, in the market power of existing
small-to-medium enterprises, etc.
The long-term goal of the promotion of translational research
is to prepare academic scientists and clinical researchers for a
paradigm shift that will happen in the near future. This shift will
emphasize the number of patents filed and amount of funding
raised as opposed to “simply” high-impact publications within
academia and securing national research funds, which are the
current factors when measuring the productivity / success of
a lab/clinic. The need to diversify funds (eg, industry, private
donors, foundations, etc.) and demonstrate / realize innovation
will be key factors for the future success of a clinic/research lab.
And as mentioned in our editorial published earlier this year:
The New Translational Research Section of the
Journal of Refractive Surgery
Concomitantly and without knowing of each other, the Journal
of Refractive Surgery (JRS) and the Association for Research in
Vision and Ophthalmology (ARVO) were on similar grounds
when giving the concept of translational ophthalmology more
room: the JRS started its section on translational research,
whereas the motto of ARVO 2012 was “Translational ophthalmology.” Moreover, ARVO also created a new journal dedicated
to translational research in ophthalmology, TVST, Translational
Vision Science and Technology.
The concept of our new section in the JRS is to give articles a
platform that tries to answer questions that arise in clinics with
the means of laboratory science. The following are representative
of typical articles published in this new section:
1. Meduri A, Aragona P, Grenga PL, Roszkowska AM.
Effect of basic fibroblast growth factor on corneal epithelial healing after photorefractive keratectomy. J Refract
Surg. 2012; 28(3):220-223.
2. Santhiago MR, Barbosa FL, Agrawal Vet al. Short-term
cell death and inflammation after intracorneal inlay
implantation in rabbits. J Refract Surg. 2012; 28(2):144149.
3. Tandon A, Tovey JC, Waggoner MRet al. Vorinostat: a
potent agent to prevent and treat laser-induced corneal
haze. J Refract Surg. 2012; 28(4):285-290.
Addressing these business and financial components of research,
we believe that including a section on translational vision research
especially for refractive surgery will be a welcomed addition to the
readership of the JRS. Although the section “Translational refractive
research” is new to the JRS, it has published a number of articles in
the past years that would have been ideal candidates for such a section. The JRS’s inaugural article will be an innovative work from
Santhiago’s group on short-term cell death and inflammation after
intracorneal inlay implantation in rabbits. Although not all scientists
are in agreement with the promotion of this term, the JRS aims to
provide different outlooks and modern usage of translational research
in this way to advance the field of refractive surgery (Hafezi and
Kristoffersen-Hafezi, JRS, 2012).
Presbyopic Inlays
Ioannis G Pallikaris MD, D Bouzoukis MD, A Limnopoulou MD MSc, S Panagopoulou PhD,
G Kymionis MD PhD
The aim of this presentation is to familiarize the participants
with a new technique of treating presbyopia, which is the
implantation of intracorneal inlays in emmetropic presbyopic
patients. A short review of the latest results of the currently used
inlays is presented, along with the presenter’s personal experience with the intracorneal inlay Flexivue Microlens.
The lens was implanted inside a corneal pocket created in the
nondominant eye of 45 patients using femtosecond laser. Mean
UCVA for near increased from 20/100 to 20/25 and for distance
decreased from 20/20 to 20/40 in the operated eye, whereas it
remained stable binocularly. After surgery 92% reported no use
of reading glasses. No intra-/postoperative complications were
found.
Final conclusions state that intracorneal lenses for presbyopia
are a safe and effective method in patients aged 45 to 60 years
old.
127
128
Trends in Refractive Surgery Survey
Richard J Duffey MD
N ot e s
Keynote Lecture
129
The Future of Laser Refractive Lens Surgery
Michal A Lawless MD
I was privileged to perform femtosecond laser cataract surgery
(LCS) in February 2011 with Professor Zoltan Nagy, and we
installed a system in our private group practice in Sydney, Australia, in April 2011. Given that our past year may have some relevance to your immediate future, what has our group learned?1
• Are the visual results better than manual surgery?
LCS brings precision and reproducibility to the capsulotomy. Does this translate to a visual benefit? When
comparing best manual surgery (n = 40) compared with
my initial LCS using a toric monofocal lens (n = 73), the
absolute difference from intended spherical equivalent
was 0.39 D (± 0.30 D) in the manual group and 0.28 D (±
0.26 D) in the laser group (P = .07). Not quite statistically
significant, but the trend is there. Using the ReSTOR multifocal IOL with best manual surgery, on some metrics I
was better: with 75% of the LCS group achieving 20/25 or
better unaided compared with 60% of the manual cataract
surgery group (P = .024). For all IOLs my personalized
surgeon factor is now higher, indicating that the IOL is
more posterior. The new LCS environment is producing a
different IOL position.
LCS appears to produce better unaided vision: statistically
significant and individually relevant for patients.
LCS requires a paradigm shift in thinking.
This is a new operation, not simply an alteration of technique. It
requires a new language. Capsulotomies are done with an energy
setting of 15 microjoules and a spot layer of 4:3 with an offset
of 250 µm below and 300 µm above the anterior capsule. The
primary incision is a 3 plane reverse trapezoidal configuration
of 2.6 mm internally and 2.3 mm externally, 1.8 mm in length
with an energy setting of 6.2 milojoules. A surgeon needs to be
as familiar with these terms as they are with the settings on their
phaco device, and must be able to adjust when needed.
The operating environment is different. Laser-generated gas
increases the capsular bag volume. The nucleus fragmentation
technique is altered; there are laser-induced changes within the
cortex that make cortical removal different; less viscoelastic is
required, and hydrodissection may be eliminated. With this new
environment, both expected and unexpected problems arise,
such as capsular block syndrome.2,3 The problems that some
within our group experienced are now understood and avoidable.4 Hardware and software continues to evolve as a result of
clinical experience.
• What does the future hold?
Femtosecond cataract lasers are now used in 34 countries,
each with their own peculiar financial and regulatory
framework. The one defining characteristic of a successful
installation is the commitment of the surgeons and their
belief that it brings a benefit to patients.
– For the technology:
Just as femtoLASIK coexists with mechanical microkeratomes, so does LCS coexist with manual surgery.
There is a place for both, but the more precise, reproducible, and expensive technology will eventually
dominate. Femtolasers suited to both LASIK and lens
surgery will become standard.
There are technical challenges to overcome. In particular this is still large pupil surgery, effectively excluding
patients who may benefit most.
The toric axis will be marked, with the laser, on the
anterior capsule, right where we want it, eliminating
parallax errors and subjective surface ink marks.
LCS began based on a phaco approach. Innovative surgeons will branch out from the traditional, exploring
techniques / settings to make better use of the precision
and reproducibility that the laser offers.
Now that we can place the capsulotomy over the center of the entrance pupil we need to make sure that is
where the IOL remains centered.
Your future is not our past.
We can do something new. LCS gives us a method for dealing
with astigmatism that did not previously exist. For example in
patients with 0.6 to 1.10 D of corneal astigmatism I use on-axis
surgery plus a single intrastromal incision in the steep axis, at
9-mm radius for 3 clock hours, set 60 µm from the epithelium
and 80 µm from the endothelium. These intrastromal cuts avoid
the surface irritation common with limbal relaxing incisions and
can be opened postoperatively to titrate the effect if needed.5
Questions to ask regarding femtosecond laser
refractive surgery:
• Is it safer than manual surgery?
Our group’s study of 1300 eyes treated (after the first 200)
demonstrates that LCS can be as safe as manual surgery,
with an anterior capsular tear rate of 0.31% (n = 4/1300).
In my personal series of the first 450 consecutive eyes, the
anterior capsular tear rate was zero, better than the 1% I
could achieve with manual surgery (P = .033) and better
than the best published data in the world from Marques
group (P = .058).
One year on LCS is safer than I can achieve with my best
manual technique. So it can be for any careful surgeon.
– For practice patterns:
With precision and reproducibility the next step is
automation and delegation. To bring this technology
to a world population will require delegation of parts
of the procedure so that the ophthalmic surgeon is presented with the lasered patient in the operating room in
an efficient manner.
130
Keynote Lecture
The cognitive decisions surrounding lens surgery
should be simplified. Currently information comes
from a variety of sources: biometry, keratometry,
topography. IOL selection and incision types are
decided individually. It is time intensive and subject to
errors and bias; with neural networking the process
could be refined and a suggested plan given to the surgeon.
Our future will be dictated not just by a more precise
laser delivery integrated with high quality imaging, it
will be linked with intelligent decision making, which
allows the surgeon to more precisely plan and deliver
the outcome for the patient.
That is the near future for all of us.
References
1. Lawless M, Hodge C. Femtosecond laser cataract surgery: an experience from Australia. Asia Pacific J Ophthalmol. 2012; 1:5-10.
2. Roberts TV, Sutton G, Lawless MA, Jindal-Bali S, Hodge C. Capsular block syndrome associated with femtosecond laser assisted
cataract surgery. J Cataract Refract Surg. 2001; 37(11):2068-2070.
3. Jindal-Bali S, Hodge C, Lawless M, Roberts TV, Sutton G. Early
experience with a femtosecond laser for cataract surgery. Ophthalmology 2012;119(5): 891-899.
4. Roberts T, Lawless M, Jindal-Bali S, Hodge C, Sutton G. Safety and
efficacy of femtosecond laser cataract surgery: a prospective study
1500 consecutive cases. Submitted for publication 2012.
5. Lawless MA. My cataract surgery technique and incision. Refractive Surgery Today. March 2012: 1-2.
Section IX: Laser Refractive Lens Surgery Symposium
131
Which Patients Truly Benefit From Laser Refractive
Lens Surgery?
Michael C Knorz MD
The history of cataract surgery dates back to at least 800 BC
when Sushruta in India described the technique of couching in
his extensive textbook Sushruta Samhita. It took more than 2500
years for Jaques Daviel of France to invent extracapsular cataract
extraction (ECEE) in 1747. Another 200 years later, in 1950, Sir
Harold Ridley implanted the first posterior chamber IOL into a
human eye in London; and not even 20 years later Charles Kelman introduced phacoemulsification in 1967.1 Dr. Kelman had
to fight a long battle until his technique was finally adopted.
Today, phacoemulsification is the gold standard of cataract
surgery all over the world. Its rise was made possible, among
other things, by the invention of capsulorrhexis, the use of foldable IOLs, which can be implanted through an incision as small
as 2 mm or even less, and the routine use of viscoelastics. Now,
a little more than 40 years later, a totally new and unique way of
lens replacement surgery has arrived: laser refractive lens surgery
with a femtosecond laser!
Laser surgery of the crystalline lens has been tried before: A
conventional YAG-laser was used in some studies to “soften” the
lens prior to phacoemulsification.2 A YAG-laser was also used to
open the anterior lens capsule, but this technique understandably
never gained much popularity as a capsulorrhexis is far superior
to a “can-opener” style of capsular opening.2 A YAG-laser was
also used by Dodick to replace ultrasound in a modified “lasertip.”3
The technique of laser refractive lens surgery using a femtosecond laser, however, is quite different. The laser is not just used
to liquefy or chop the nucleus, it also performs a perfect capsulorrhexis, it creates the incisions, and it can be used to correct
corneal astigmatism. This new technique of laser refractive lens
surgery with a femtosecond laser has therefore a lot more potential than former laser lens surgery approaches.
Prof. Zoltan Nagy at the Semmelweis University in Budapest,
Hungary, performed the first laser refractive lens surgeries with
a femtosecond laser in 2008.4 He used the LenSx femtosecond
laser, built by LenSx, Inc. (Aliso Viejo, Calif., USA). Alcon
acquired this company in 2010, and the first commercial lasers
were sold in 2010.
Has laser refractive lens surgery with a femtosecond laser
opened the door to a new era of lens and cataract surgery? Will
patients benefit from this procedure?
Published data show that a laser capsulorrhexis is better than
a manual one,4-6 that higher-order aberrations are less after a
laser capsulorrhexis than after a manual one,7 due to less IOL
tilt, and that refractive outcomes are better after laser-refractive
lens surgery.10 Published data also show that laser refractive lens
surgery causes less corneal edema9 and less thickening of the
macula.11 These studies therefore suggest that laser refractive lens
surgery has better results than manual phacoemulsification. On
the other hand, laser refractive lens surgery may be associated
with complications such as anterior capsule tears, capsular block
syndrome, and posterior capsule rupture.12,13
How does it compare to conventional surgery? The incidence of anterior capsule tears in residents was reported to be
5.3%, and posterior capsule tears with vitreous loss occurred in
6.6%.15 This compares to 4% anterior radial tears and 3.5%
posterior capsule tears during the learning curve of the first 200
cases operated with laser refractive lens surgery.12
In the hands of an experienced surgeon, anterior capsule tears
occurred in 0.8%.14 Of those, 40% extended onto the posterior
capsule, and 20% caused vitreous loss.14 Finally, out of 602,553
cataract procedures performed between 2002 and 2009, an incidence of 2.09% of posterior capsule tears was reported in the
Swedish National Cataract Register.16 This compares to an incidence of anterior capsule tears of 0.32% and posterior capsule
tears of 0.31% (0.08% without vitreous loss and 0.23% with
vitreous loss) observed in 1300 eyes treated with laser refractive
lens surgery (Roberts et al, Syndey, unpublished data of a prospective study on 1300 eyes treated with the LenSx femtosecond
laser).
Based on the data published so far, laser refractive lens surgery seems to be at least as good and possible better than manual
phacoemulsification, and at least as safe and possibly safer than
manual phacoemulsification.
Patients likely to benefit most are those with large pupils,
which will give the laser access to the lens capsule and nucleus. In
patients with small pupils, corneal incisions and arcuate cuts to
reduce corneal astigmatism may still be performed, but a capsulorrhexis and nucleus fragmentation are not possible.
Regarding nucleus density, the laser procedure is the easier
the softer the nucleus is, and not possible in brown or white
nuclei. However, even in hard nuclei (LOCS IV), prefragmentation with the laser reduces the amount of phaco energy and
therefore causes less corneal edema.9
In conclusion, based on currently published data it seems
likely that most patients will benefit from laser refractive lens
surgery.
References
1. Kelman CD. Phaco-emulsification and aspiration: a new technique
of cataract removal—a preliminary report. Am J Ophthalmol.
1967; 64:23-35.
2. Chambless WC. Neodymium:YAG laser anterior capsulotomy
and a possible new application. J Am Intraocul Implant Soc. 1985;
11:33-34.
3. Dodick JM, Christiansen J. Experimental studies on the development and propagation of shock waves created by the interaction of
short Nd:YAG laser pulses with a titanium target: possible implications for Nd:YAG laser phacolysis of the cataractous human lens. J
4. Nagy Z, Takacs A, Filkorn T, Sarayba M. Initial clinical evaluation
of an intraocular femtosecond laser in cataract surgery. J Refract
Surg. 2009; 25:1053-1060.
5. Nagy ZZ, Kránitz K, Takacs AI, Miháltz K, Kovács I, Knorz MC.
Comparison of intraocular lens decentration parameters after
femtosecond and manual capsulotomies. J Refract Surg. 2011;
27(8):564-569.
6. Kránitz K, Takacs A, Miháltz K, Kovács I, Knorz MC, Nagy ZZ.
Femtosecond laser capsulotomy and manual continuous curvilinear
132
capsulorrhexis parameters and their effects on intraocular lens centration. J Refract Surg. 2011; 27(8):558-563.
7. Miháltz K, Knorz MC, Alio JL, Takacs AI, Kránitz K, Kovács I,
Nagy ZZ. Internal aberrations and optical quality after femtosecond laser anterior capsulotomy in cataract surgery. J Refract Surg.
2011; 27(10):711-716.
12. Bali SJ, Hodge C, Lawless M, Roberts TV, Sutton G. Early experience with the femtosecond laser for cataract surgery. Ophthalmology 2012; 119:891-899.
13. Roberts TV, Sutton G, Lawless MA, Jindal-Bali S, Hodge C. Capsular block syndrome associated with femtosecond laser-assisted
cataract surgery. J Cataract Refract Surg. 2011; 37:2068-2070.
8. Kránitz K, Takacs A, Miháltz K, Kovács I, Knorz MC, Nagy ZZ.
Intraocular femtosecond laser use in traumatic cataracts following
penetrating and blunt trauma. J Refract Surg. 2012; 28(2):151-153.
14. Marques FF, Marques DM, Osher RH, Osher JM. Fate of anterior
capsule tears during cataract surgery. J Cataract Refract Surg. 2006;
32:1638-1642.
9. Takacs AI, Kovacs I, Mihaltz K, Filkorn T, Knorz MC, Nagy ZZ.
Central corneal volume and endothelial cell count following femtosecond laser-assisted refractive cataract surgery compared to conventional phacoemulsification. J Refract Surg. 2012; 28:387-391.
15. Unal M, Yücel I, Sarici A, Artunay O, Devranoğlu K, Akar Y, Altin
M. Phacoemulsification with topical anesthesia: resident experience. J Cataract Refract Surg. 2006; 32:1361-1365.
10. Filkorn T, Kovacs I, Takacs A, Horvath E, Knorz MC, Nagy ZZ.
Comparison of IOL power calculation and refractive outcome after
laser refractive cataract surgery with a femtosecond laser versus
conventional phacoemulsification. J Refract Surg. 2012; 28.
11. Ecsedy M, Miháltz K, Kovács I, Takacs A, Filkorn T, Nagy ZZ.
Effect of femtosecond laser cataract surgery on the macula. J
Refract Surg. 2011;27:717-722.
16. Lundström M, Behndig A, Kugelberg M, Montan P, Stenevi U,
Thorbun W. Decreasing rate of capsule complications in cataract
surgery: eight-year study of incidence, risk factors, and data validity
by the Swedish National Cataract Register. J Cataract Refract Surg.
2011; 37:1762-1767.
Technique Pearls for Success in Laser Refractive
Lens Surgery
Notes
133
134
Spherical Refractive Accuracy: More Accurate, and
Only Small A-Constant Optimization
Robert J Cionni MD
I.Overview
C. Comparison of the mean absolute error (MAE)
A. Capsulotomy performed by a femtosecond laser vs.
conventional method provides better predictability
in effective lens position (ELP) and more stability of
IOL at 1 month.
D. While “personalized” lens constant was used on
both groups, further optimization of the “personalized” lens constant is calculated. Comparison of the
calculated new MAE.
B. Spherical refractive accuracy requires lens constant
optimization; however, it is less frequent in laser
refractive lens surgery methodology.
E. Regression comparison between preop and postop
ACD at 1 and 6 months.
F. IOL stability comparison
II. Clinical Science
A. “The relationship between capsulorhexis size
and anterior chamber depth relation”—article by
Osman Cekic MD and Cosar Batman MD
B. Conclusion: “A 4 mm capsulorhexis results in a
longer postoperative ACD than does a 6 mm capsulorhexis for the IOL type used in this study.”
III. Clinical Study Methodology
A. Single lens type (SN60WF)
B. April 4, 2011 through June 14, 2011; single center,
nonrandomized, prospective study
C. All cases operated by 1 surgeon (Robert Cionni
MD)
D. Manual group (n = 26); attempted 5.0-mm capsulotomy
E. Mastel 5.75-mm optical zone marker to create 5.0mm continuous curvilinear capsulorrhexis
F. LenSx laser group (n = 22); femtosecond laser created 5.0-mm capsulotomy
G. 1-month/6-month follow-up
1. Accuracy to target, UCVA
2. LenSTAR LS 900 used to measure 1-month and
6-month postop anterior chamber depth (ACD)
3. LADARVision aberrometry at 6-month postop
visit
VI. ELP Predictability at 1 Month
VII. ELP Predictability at 6 Months
VIII. Prediction Error Comparison
IX. Prediction Error at 1 Month Postop
X. Optimizing Lens Constant
XI. “Calculated” New Prediction Error*
XII. Prediction Error at 6 Months Postop
XIII. ACD Comparison at 1 Month
XIV. ACD Comparison at 6 Months
XV. IOL Stability at 6 Months
XVI. Efficacy Distribution at 1 Month
XVII. Efficacy Distribution at 6 Months
XVIII.Conclusions
A. ELP is more predictable and more highly correlated
with postop ACD in laser capsulotomy than in
manual capsulotomy.
B. Lens constant optimization is essential for better
predictability of ELP, which leads to better refractive accuracy.
C. Continuation of lens constant optimization
improved the prediction error in the manual group;
however, the refractive accuracy in the laser capsulotomy maintained a higher level of accuracy.
IV. Demographic and Preop Comparison Analysis
Methodology
V. Analysis Methodology
A. Using refractive vergence formula to calculate predicted ELP following Jack Holladay’s published
methodology
B. Regression comparison between predicted ELP and
postop ACD at 1 and 6 months
1. Higher frequency to optimize lens constant in
manual capsulotomy than laser capsulotomy
(less variability in laser group).
D. Recommend to optimize lens constant for laser capsulotomy cases separate from manual capsulotomy
cases.
135
Spherical Refractive Accuracy: Requires A-constant
Optimization
I. Sources of Error in IOL Power Calculations
1. Calculate the arithmetic average of the absolute
error in the spheroequivalent of the predicted
refraction from the actual refraction.
2. Using a density plot, the sum of the prediction
errors (D) above and below the mean will be
equal.
Sverker Norrby analysis – parameters (Norrby S. J
Cataract Refract Surg. 2008; 34:368-376.)
A. First 9 variables = 98.9% of error (nominal SD = ±
0.60 D)
1. Predicted anterior chamber depth (ACD) =
35.5% (± 0.21 D)
2. Postop spectacle refraction = 27.0% (± 0.13 D)
3. Axial length = 17.0% (± 0.10 D)
4. Pupil size = 8.1% (± 0.05 D)
5. Corneal posterior/anterior radius ratio = 3.7% (±
0.02 D)
6. Anterior corneal asphericity (Q-value) = 2.5% (±
0.02 D)
7. Anterior corneal radius = 2.3% (± 0.01 D)
8. Corneal refractive index of refraction = 1.6% (±
0.01 D)
9. IOL power = 1.2% (± 0.01 D)
1. Vitreous index of refraction
2. Aqueous index of refraction
3. Retinal thickness
4. Posterior corneal asphericity (Q-value)
5. Corneal thickness
6. Chart distance
7. Air index of refraction
1. Calculate the standard deviation of the spheroequivalent of the predicted refraction from the
actual refraction.
2. Using a density plot, the area within the SD will
be 68%.
B. Remaining 7 variables combined = 1.1% of error (±
0.01 D)
B. Standard deviation (SD)
C. The SD to MAE ratio should be 1.36 (0.68/0.50)
theoretically, but is usually about 1.20 empirically
due to the absence of large numbers in prediction
errors.
IV. Nominal Prediction Errors in Recent Studies: ORA
(previously Orange from Wavetec)
A. Recent normals from literature: MAEs—0.36 to
0.48 D—and STDS—0.43 to 0.58 D—are excellent
results without intraoperative aberrometry.
B. Post LASIK (Wang L. J Cataract Refract Surg. 2010;
36:1466-1473.)
1. ORA: MAE = 0.32 ± 0.24 D (n = 314)
2. Wang: MAE = 0.46 ± 0.48 D (n = 72)
3. Haigis: MAE = 0.46 ± 0.51 D (n = 72)
4. Shammas: MAE = 0.48 ± 0.49 D (n = 72)
C. Femto vs. Manual (Hill W. Ophthalmol Times, Oct.
24, 2011)
Mean error ± SD, manual: + 0.55 ± 0.41, femto:
-0.21 ± 0.39 → difference (P = .003) is a result of
not optimizing lens constant for each procedure.
Distribution (SD) is almost identical.
II. A-Constant Optimization (Personalization) (Holladay
JT. J Cataract Refract Surg. 1988; 14:17-24.)
A function of all the variables above + surgeon differences:
A. Refractive technique, optical biometer (IOLMaster,
LenStar v. ultrasound), pupil size not even measured, keratometer (sample zones all difference),
asphericity not considered.
B. Surgeon differences: Wound design with radial and
axis orientation, type and amount of viscoelastic
with IOL insertion, rotation of IOL to final position, technic of viscoelastic removal, steroid use, . . .
III. Methods of Measuring Prediction Errors
A. Mean absolute error (MAE)
V. How do you determine whether difference is statistically significant (P ≤ .05)?
A. Must first adjust mean error (signed) to zero for
both groups, then compare MAE and SD.
B. Must calculate standard error of the mean (SEM) =
SD/√n
C. MAE: To be different @ P < .05 → MAE1 +
2 SEM1s < MAE2 – 2 SEM1s
1. ORA SEM = 0.24/√314 = 0.24/17.7 = 0.014
2. WANG SEM = 0.48/√72 = 0.48/8.48 = 0.057
3. ORA = 0.32 + 2*0.014 = 0.348 Wang = 0.46 –
2*0.057 = 0.346
136
4. Almost exactly different @ P = .05
D. SD: SD1 + 2*SEM1 < SD2 – 2*SEM2
E. Need ~ 100 cases with current MAE and SD to
prove 0.25 D difference (P < .05).
F. With ~ 400 cases with current MAE and SD to
prove 0.125 D difference (P < .05). Clinician must
determine if clinically significant (not a statistician). . . . At 0.125 D, probably not!
E. To show differences between femto cataract surgery
and manual as a result of better precision with the
cataract incision and capsulorrhexis, mean error
should be set to zero, and there will need to be a
minimum of 100 cases in each group with SDs of
0.50 D to show a difference of 0.25 D at the P ≤ .05.
F. If the MAEs and SDs are reduced to 0.25 D, then
measurements of refraction, axial length, pupil size,
Ks, and corneal asphericity must also be implemented or improved. When prediction error is 0.25
D, it would be beneficial to reduce the step-size of
IOLs to 0.25 D, but until then will be of no benefit.
G. Optimization (personalization) of lens constant is
always necessary to reduce systematic differences
from manufacturer’s global average to a specific
surgeon by entering postoperative data. Entering
the postoperative data routinely will ensure that
there are no components from any source that have
changed and ensure that there is no need for one or
more of the instruments to be recalibrated.
VI.Conclusions
A. Effective lens position (ELP) is a function of at least
16 variables, the first 9 of which account for 99% of
the variability. The largest component is the prediction of the ELP (ACD), which accounts for ~36% of
the prediction error in refraction (D) . . . ~ 0.22 D.
B. Cataract incision will be more precise in architecture (arc length, trapezoidal shape, depth, . . .) than
angular location (axis) than manual cataract incisions.
C. Capsulorrhexis size and circularity with femto laser
will be more precise than manual.
D.If most of the variability of the prediction of ELP
is due to the capsulorrhexis and cataract incision
and not the IOL power calculation formula and
other anatomic variables of the eye (anatomy of the
anterior segment [ciliary body, zonular lens plane
after cataract surgery, vault of IOL . . .]), then femto
cataract surgery could improve prediction error (D)
by ~0.22 D (0.60 D * 36% = 0.22 D).
137
Laser Refractive Lens Surgery: Advantages and Use for
Complicated Cases
Barry S Seibel MD
Notes
138
IOL Centration: Capsule Size and Shape, or IOL
Position at End of Surgery?
Daniel H Chang MD
I. Importance of IOL Centration
A. Good centration is needed for good outcomes.
1. Maximize visual quality (visual acuity, contrast
sensitivity)
2. Minimize visual side effects (halos, glare, starbursts)
i. Size, shape, and position of capsulorrhexis
ii. Design and curvature of optic surface
b. Adhesiveness of the optic material12
3. Optic edge against anterior capsular rim (if
capsular opening extends peripheral to the optic
edge)
B. The importance of good centration for aspheric
IOLs is well documented.1,2
a. Dependent on arc length and location (relative to haptic insertion) of non-overlap
C. The significance of decentration on diffractive multifocal IOLs is not well understood.
b. May be susceptible to late effects of capsular
contraction
1. Probably greater than for a monofocal aspheric
IOL
c. Possibly reduced by posterior vaulting of
some IOL designs
2. Quantitative degradation of visual performance
and increase of visual side effects is not known.
3. Tolerance probably varies with IOL design.
B. Influence of surgical parameter(s) on IOL position
II. Definition of IOL Centration
1. Precise size, shape, and position of the capsulotomy
a. Femtosecond laser capsulotomy8,9
A. Traditionally: IOL edge not seen in undilated pupil.
b. Freehand manual capsulotomy
B. Laboratory: Optical center or pupil (dilated) center3-9
c. Guided manual capsulotomy13
C.Clinically
1. Pupil (undilated) center—more aesthetically
appealing at the slitlamp
2. Visual axis—difficult to determine at slitlamp
a. Coaxially sighted corneal light reflex
b. Most logical from hyperopic LASIK studies10-11
a. Haptic position (vertical, horizontal, oblique)
b. Manual positioning
3. Same if angle kappa is small
A. Summation of vector forces between IOL and capsule
2. IOL placement?
C. Change over time
c. Can be assessed with rings/pupil image setting
on some corneal topographers
III. Theoretical Considerations in IOL Centration
1. Capsular scarring and contraction
a. Due to lens epithelial cell proliferation
b. Dependent on original capsulotomy size,
shape, and position
c. Mitigated with meticulous cortical cleanup
2. Zonular changes
IV. Observations in IOL Centration
1. Haptics in the capsular fornix
A. Ability to dictate position of one-piece hydrophobic
acrylic IOL
1. By rotating the haptic position
a. Peripheral capsular anatomy not radially
symmetric
2. By pushing the optic (orthogonal to haptic direction)
b. Areas of contact and force vary with haptic
material and design.
3. Exact degree of control dependent on IOL material and design.
c. Haptic may not be at most peripheral point in
capsular fornix.
2. Optic surface against the anterior capsular rim
and posterior capsule
a. Mechanics of the interaction
B. Intraoperative centration of IOL
1. Maintained in early postoperative period
2. Maintained throughout first postoperative year
C. Early IOL centration not apparently related to
anatomy of capsulotomy (within reasonable manual
variations of a continuous curvilinear capsulorrhexis)
V.Conclusions
A. IOL centration is primarily dependent on IOL position at the end of surgery.
B. Capsulotomy size, shape, and position may influence late changes.
1. Complete and symmetric overlap of capsulorrhexis and optic edge preferred.
2. Thorough cortical cleanup is important.
C. More studies are needed to elucidate IOL centration
and the effect of small and large IOL decentrations
on visual quality and side effects.
References
1. Holladay JT, Piers PA, Koranyi G, et al. A new intraocular lens
design to reduce spherical aberration of pseudophakic eyes. J
Refract Surg. 2002; 18(6):683-691.
2. Wang L, Koch DD. Effect of decentration of wavefront-corrected
intraocular lenses on the higher-order aberrations of the eye. Arch
Ophthalmol. 2005; 123:1226-1230.
3. Mutlu FM, Erdurman C, Sobaci G, Bayraktar MZ. Comparison
of tilt and decentration of 1-piece and 3-piece hydrophobic acrylic
intraocular lenses. J Cataract Refract Surg. 2005; 31:343-347.
4. de Castro A, Rosales P, Marcos S. Tilt and decentration of intraocular lenses in vivo from Purkinje and Scheimpflug imaging. J
139
5. Rosales P, de Castro A, Jiménez-Alfaro I, Marcos S. Intraocular
lens alignment from Purkinje and Scheimpflug imaging. Clin Exp
Optom. 2010; 93(6):400-408.
6. Crnej A, Hirnschall N, Nishi Y, et al. Impact of intraocular lens
haptic design and orientation on decentration and tilt. J Cataract
Refract Surg. 2011; 37:1768-1774.
7. Mester U, Sauer T, Kaymak H. Decentration and tilt of a singlepiece aspheric intraocular lens compared with the lens position in
young phakic eyes. J Cataract Refract Surg. 2009; 35:485-490.
8. Kranitz K, Takacs A, Mihaltz K, et al. Femtosecond laser capsulotomy and manual continuous curvilinear capsulorrhexis parameters and their effects on intraocular lens centration. J Refract Surg.
2011; 27(8):558-563.
9. Nagy ZZ, Kranitz K, Takacs AI, et al. Comparison of intraocular
lens decentration parameters after femtosecond and manual capsulotomies. J Refract Surg. 2011; 27(8):564-569.
10. Chan C, Boxer Wachler B. Centration analysis of ablation over the
coaxial corneal light reflex for hyperopic LASIK. J Refract Surg.
2006; 22:467-471.
11. Kermani O, Oberheide U, Schmiedt K, et al. Outcomes of hyperopic
LASIK with the Nidek NAVEX platform centered on the visual axis
or line of sight. J Refract Surg. 2009; 25:S98-S103.
12. Lombardo M, Carbone G, Lombardo G, et al. Analysis of intraocular lens surface adhesiveness by atomic force microscopy. J Cataract
Refract Surg. 2009; 35:1266-1272.
13. Dick HB, Pena-Aceves A, Manns M, et al. New technology for sizing the continuous curvilinear capsulorhexis: prospective trial. J
140
Precision in Optics: Why Laser Refractive Lens
Surgery Is So Critical
Zoltan Nagy MD
Cataract surgery by phacoemulsification of the crystalline lens
and implantation of an artificial IOL has become a common,
safe, and effective intervention performed worldwide today.
Modern, microincisional cataract surgery has reduced the
amount of postoperative astigmatism, and new IOL design with
sharp edges has diminished the risk of complication such as posterior capsular opacification (PCO). As these problems seemed
to be resolved, an increased interest has turned toward operation
safety and better visual quality after cataract surgery.
A precise and well-centered capsulorrhexis is a crucial step
in cataract surgery. The surgical technique of manual capsulorrhexis, regarding centration, diameter, and shape, has up to
now not been improved, because there was no alternative of the
manual rrhexis. But with the advent of the femtosecond lasers
for cataract surgery a new horizon appeared for achieving a better and more predictable capsulotomy.
This effect is called photodisruption. A capsulotomy with
360-degree overlapping of the PCL prevents optic decentration,
tilt, myopic shift, and PCO due to symmetric contractile vector forces of the capsular bag and the shrink-wrap effect. This
technology also has the potential to reduce the risk of capsular
tear and other complications such as inflammation and endophthalmitis, creating self-sealing corneal incisions. Moreover the
reduction of effective phaco power and phaco time increases the
safety of the procedure, not increasing the temperature of the
aqueous. During the presentation change of higher-order aberrations, change in quality of postoperative visual acuity, and safety
results will be discussed.
Imaging Accuracy Is Critical in Laser Refractive
Lens Surgery
Gerd U Auffarth MD
Notes
141
142
Astigmatic Keratotomy in Laser Refractive
Lens Surgery: Comparison of Simultaneous and
Separate Surgeries
Eric Donnenfeld MD
Management of astigmatism is the single most important aspect
of the ability to provide good surgical outcomes, quality of
vision, and satisfaction for patients requesting refractive cataract surgery and optimal postoperative UCVA. Astigmatism
decreases visual acuity through meridional blur, in which one
axis of the cornea is steeper than the other, causing distortion of
the visual image. Residual astigmatism after cataract surgery of
0.50 D or even less may result in glare, symptomatic blur, ghosting, and halos.1 As a result, greater emphasis has been placed on
treating corneal astigmatism at the time of cataract surgery with
limbal relaxing incisions (LRIs). A recent study of 4540 eyes of
2415 patients showed that corneal astigmatism is present in the
majority of patients undergoing cataract surgery, with at least
1.50 D measured in 22.2% of study eyes.2 Approximately 38%
of eyes undergoing cataract surgery have at least 1.00 D of preexisting corneal astigmatism, and 72% of patients have 0.5 D or
more.3
Astigmatic incisions are corneal incisions that are used to
relax and flatten the steep axis of regular corneal astigmatism
while steepening the flat axis. The procedure reduces corneal tension and allows the cornea to heal into a more spherical shape.
Incisions placed adjacent to the limbus are LRIs, and incisions
placed further from the limbus and closer to the visual axis are
astigmatic keratotomies. Because there are several advantages
of LRIs over astigmatic keratotomies, LRIs are performed more
frequently. These advantages include a reduced tendency to
cause axial shift, less irregular astigmatism, a 1:1 coupling ratio,
a decreased chance of visually significant scarring, and a reduced
likelihood of perforation. Unfortunately, the majority of cataract
surgeons are uncomfortable performing manual incisional astigmatic incisions. In a survey of 233 surgeons, only 73 routinely
performed LRIs.4
Many LRI nomograms are adjusted for age and cylinder axis,
making them detailed and complex and giving the impression
that the procedure is extremely precise and unforgiving. In my
opinion, however, this simply is not the case. The LRI procedure
has numerous chances for error, and the many variables that
help determine how the incision is performed can each be measured incorrectly. The incision itself, if performed manually, is
only as precise as the surgeon making the incision and the accuracy of the blade. Any of these errors can compound and result
in suboptimal visual acuity. Manual LRIs are therefore as much
an art as a science.
In addition, the phacoemulsification incision must be factored
into the preoperative corneal astigmatism to determine the final
postoperative residual cylinder. Using vector analysis, the surgeon should determine the proper axis to perform an astigmatic
incision. All of these factors can be calculated online at www.
LRIcalculator.com (see Figure 1). The online LRI calculator uses
vector analysis to calculate where to make LRI incisions based
on preoperative patient keratometry and the surgeon’s induced
astigmatism; it also uses the Donnenfeld and Nichamin nomogram and provides a visual map of the axis and length of inci-
sions that should be performed. A printout of the LRI calculator
can be brought to the operating room and used as a guide when
marking the cornea and performing LRIs.
Figure 1. The Donnenfeld Nomogram is available on the Internet at:
www.LRIcalculator.com.
Recent developments in femtosecond laser technology have
shifted attention from manual LRI and astigmatic keratotomy
procedures to femtosecond laser-guided procedures. These procedures offer a greater degree of precision and accuracy than
manual methods.5 The treatment of astigmatism during cataract
surgery with femtosecond laser astigmatic incisions is an interesting development in femtosecond technology, which is positioned
to revolutionize refractive cataract surgery.
Femtosecond lasers are photodisruptive lasers with extraordinarily short pulse durations of less than 800 femtoseconds (1
femtosecond is 10-15 seconds). This extremely short pulse duration allows femtosecond lasers to cut tissue with considerably
less energy than traditional lasers used in ophthalmic surgery.
Per-pulse energies can be reduced approximately 1000‐fold, from
around 1-10 millijoules for nanosecond lasers (neodymium-doped
yttrium aluminum garnet [Nd:YAG]) to 1-10 microjoules for
femtosecond lasers. These reductions in per-pulse energy result
in substantial reductions in collateral tissue damage, shifting
from a few millimeters from the intended target for nanosecond
lasers to just a few microns for femtosecond lasers. Similar to the
Nd:YAG laser systems, femtosecond laser pulses pass through
transparent tissues and can be focused at a predetermined
depth.6
The U.S. Food and Drug Administration has approved 510(k)
clearance for the use of femtosecond lasers for clinical applications in cataract surgery. The most remarkable features of laser
cataract surgery include the precision of the performed incisions
with minimal collateral damage to surrounding tissues, accuracy
of capsulotomy dimensions and diameters, enhancement of cap-
sular edge strength, reduction of phaco power in lens fragmentation, and improved wound sealing and healing—all of which
lead to better and more reproducible results compared with
manual, mechanical surgeries.
A major clinical application of the femtosecond laser is in
creating arcuate incisions that have precise and accurate arc
length, depth, angular position, and optical zone. The femtosecond laser allows for precise and repeatable incisions, which are
necessary for consistent results not normally achieved through
manual methods.7 In a case study, femtosecond laser arcuate
keratotomy was used to correct astigmatism. The refraction of
the patients’ eyes was measured along with the corneal thickness. Then the keratometric parameters were evaluated, and the
femtosecond laser created the incisions, the length and position
of which were calculated individually, per eye. OCT-controlled
corneal pachymetry was performed directly in the area of the
intended incisions and then programmed into the laser, which
allows for extremely high levels of precision. The study results
showed that with the femtosecond laser, astigmatism could be
better corrected with an improved BCVA than was predicted in
the preoperative values. Furthermore, the depth and location of
the incisions were consistent with the surgical plan. Laser technology is able to create uniform corneal incisions precisely and
predictably.8
Femtosecond lasers allow for more efficacious and safer surgical procedures. The corneal tissue does not absorb the laser
wavelength. The photodisruption dissipates within 100 μm of
the target, millimeters away from the cornea, which allows for a
higher margin of safety because a sizeable distance is kept from
Descemet’s membrane, preventing perforation. Moreover, the
laser can be programmed to create an ideal wound shape for
enhanced sealing and healing of the incisions with reproducible induction of astigmatism that cannot be achieved with the
use of manual keratomes. Femtosecond laser incisions provide
superior reproducibility and reduced variability compared with
conventional manual incisions.9 In a study of initial results with
the LenSx femtosecond laser, using 9-mm arcuate incisions and
a 33% reduction of the Donnenfeld nomogram, a 70% reduction in astigmatism was achieved.10 Femtosecond laser incisions
can also be placed intrastromally in the sub-Bowman layer of
the cornea, which improves healing by sparing corneal epithelial
damage. Further clinical investigation and nomogram development are currently under way to optimize this method, which
would eliminate the need for corneal wound manipulation on the
surface.
The surgical technique for performing femtosecond laser
arcuate incisions first involves determining the length, position,
depth, and distance from the visual axis where the incisions will
be created. We use a 33% reduction of the Donnenfeld nomogram and use the LRI calculator (www.lricalculator.com) to
determine the length and axis at which the incision should be
placed (see Figure 3). We preset the depth of our incisions to
85% of the corneal pachymetry in the area of the incision. We
have set our distance from the visual axis at 9 mm. This information is all downloaded onto the femtosecond laser (LenSx). We
then begin the surgical procedure by docking the laser onto the
cornea. An overlay of the incisions is then visible on the surgical
screen (see Figure 2). OCT imaging of the cornea in the area of
the arcuate incision is then visualized, and the depth is confirmed
(Figure 3). We first perform the capsulotomy, followed by the
lens disruption, and then create our corneal incisions. Following
the conclusion of the femtosecond laser treatment, the patient
143
is brought to the operating microscope and the incisions are
opened with a Sinskey hook (see Figure 4). Intraoperative aberrometry (Orange; WaveTec Vision; Aliso Viejo, Calif., USA)
may then be performed to titrate the opening of the incisions.
The incisions are symmetric and standardized at 9 mm from the
visual axis (see Figure 5). OCT confirms the postoperative depth
of the incisions (see Figure 6). If needed, the arcuate incisions
may be opened postoperatively in the office at the slit lamp using
forceps or a Sinskey hook and topical anesthetic (see Figure 7).
Figure 2. Overlay of the arcuate incisions.
Figure 3. OCT imaging of the cornea in the area of the arcuate incision.
144
Figure 4. Sinsky hook used to open the femtosecond arcuate incisions.
Figure 5. Femtosecond arcuate incisions being performed.
Figure 6. OCT demonstrating the depth of the arcuate incision.
Figure 7. Forcep used to open the femtosecond arcuate incision at the
slitlamp.
A major advantage of femtosecond arcuate incisions is that
the refractive incisions may now be made before cataract surgery
and then modified intraoperatively and/or postoperatively. The
incisions are performed with the femtosecond laser but do not
have significant effect until they are opened. To further refine
our results, we have been performing intraoperative aberrometry
(ORange) to titrate our results in the operating room. We remove
the cataract, place the IOL, and open one of the femtosecond
incisions with a Sinskey hook. The IOP is then raised to approximately 25 mmHg. Next, we perform intraoperative aberrometry,
which provides a very accurate reading of the existing astigmatism. The second femtosecond incision may then be opened
partially or completely, based on the intraoperative aberrometry
reading, which, if needed, can be taken again. For surgeons who
do not have access to intraoperative aberrometry, patients can
be examined with topography and refraction, performed the day
after surgery. If needed, the remainder of the incision can be easily opened in the office to increase the effect of the incision and
adjust the residual astigmatic refractive error.
In conclusion, the creation of femtosecond laser-assisted
arcuate incisions is a novel technique that provides the precision
of image-guided laser technology. Refractive incisions are now
computer controlled and do not rely on surgeon skill or experience. The use of a femtosecond laser system will provide faster,
safer, easier, customizable, adjustable, and fully repeatable astigmatic incisions. Removing the inconsistencies in the astigmatic
procedure will improve our understanding and accuracy of astigmatic incisions and should provide improved refractive results
and patient satisfaction.
References
1. Nichamin LD. Nomogram for limbal relaxing incisions. J Cataract
Refract Surg. 2006; 32(9):1048.
2. Ferrer-Blasco T, Montés-Micó R, Peixoto-de-Matos SC, GonzálezMéijome JM, Cerviño A. Prevalence of corneal astigmatism before
cataract surgery. J Cataract Refract Surg. 2009; 35(1):70-75.
3. Hill W. Expected effects of surgically induced astigmatism on
AcrySof toric intraocular lens results. J Cataract Refract Surg. 2008;
34(3):364-367.
4. Duffey RJ, Leaming D. US trends in refractive surgery: 2008 ISRS/
AAO survey. ISRS/AAO 2008. Refractive and Cataract Surgery:
Today and Tomorrow. Meeting Guide of the 2008 AAO Subspecialty Day. San Francisco: AAO; 2008.
5. Masket S, Sarayba M, Ignacio T, Fram N. Femtosecond laserassisted cataract incisions: architectural stability and reproducibility. J Cataract Refract Surg. 2010; 36(6):1048-1049.
6. Vogel A, Noack J, Hüttman G, Paltauf B. Mechanisms of femtosecond laser nanosurgery of cells and tissues. Appl Phs B. 2005;
81:1015-1047.
7. Nichamin L. Femtosecond laser technology applied to lens-based
surgery. Medscape Ophthalmology. June 22, 2010. www.medscape
.com/viewarticle/723864. Accessed July 20, 2011.
8. Nagy Z, Takacs A, Filkom T, Sarayba M. Initial clinical evaluation
of an intraocular femtosecond laser in cataract surgery. J Refract
Surg. 2009; 25(12):1053-1060.
9. Abbey A, Ide T, Kymionis GD, Yoo SH. Femtosecond laser-assisted
astigmatic keratotomy in naturally occurring high astigmatism. Br J
Ophthalmol. 2009; 93(12):1566-1569.
10. Slade SG. Femtosecond laser arcuate incision astigmatism correction in cataract surgery. Presented at: ASCRS Cornea Day; March
25, 2011; San Diego, CA.
145
146
Can Laser Refractive Lens Surgery Really Work for
You and Your Practice?
Stephen G Slade MD
Much of what we have studied about femtosecond laser cataract
surgery details the benefits that the technology offers to our
patients. I believe, and increasingly the evidence supports, that
cataract surgery safety itself will be enhanced by reduced phaco
time and power, less surgical time in the eye, and finer, more
elegant incisions, among other innovations. Precision may be
increased by an exactly sized, shaped, and positioned capsulotomy that will better control the IOL’s final resting place as well
as by precise, reproducible primary incisions and standardized,
quantifiable astigmatic keratotomies. Femtosecond lasers could
also enable and make possible many other technologies, including advanced accommodating IOLs and polymer IOLs that can
be injected through a tiny capsulotomy.
However, most of the heated debate about femtosecond
laser-assisted cataract surgery has not been about the capabilities of the technology, but rather its real-world practicality. Will
patients seek it out? Is it economical? Who will pay for it? Will it
work in your practice? I have a unique perspective. I have been
performing laser cataract surgery commercially in Houston for
nearly 3 years now on all of our practice’s premium IOL patients
and most of our other cataract patients.
When LenSx Lasers, Inc. (Aliso Viejo, Calif., USA) delivered
the platform to us in February 2010, it already had 510(k) clearance for anterior capsulotomy, and clearance for incisions and
lens fragmentation quickly followed. In my experience, patients
easily understand and prefer “laser” cataract surgery, and they
seek it out. Yes, there are added costs to treat astigmatism with
the laser. This is not covered by Medicare, however, so patients
can assume these costs if they so choose. In other words, patients
can elect to pay for what they decide is better care, safety, and
efficiency.
We offer our patients three options based on what they want
out of their surgery. If they desire the best chance for glassesfree vision, we offer a presbyopia-correcting IOL, any needed
astigmatism correction, and the laser to help with the removal
of the cataract. If a patient does not mind reading glasses, but
has astigmatism that he wants surgically corrected, we offer to
fix the astigmatism with the laser or a toric IOL along with laser
cataract surgery. A third option is traditional cataract surgery,
a monofocal IOL, no astigmatism correction, and fully manual
surgery. In the three years we have worked in this framework we
have found excellent patient acceptance, improved results, and a
growing surgical base.
On January 1, the first baby boomers turned 65 and entered
Medicare, with an estimated 10,000 hitting that milestone each
day now. The U.S. population over the age of 65 is projected to
double in 7 years. I believe the development and availability of
laser cataract surgery are right on time.
147
Corneal or Lens Refractive Surgery?
I.Background
A. Cataract surgery is the most common refractive surgical procedure.
B. Improved understanding of candidacy for corneal
refractive surgery
C. Improved technology for both corneal and lens
based procedures
V. Good Candidate for Lens Replacement
A. 45 or older
B. Myope, presbyope, hyperope
C. Lens changes
D. Healthy retina (macula and periphery)
VI. Good Candidate for Phakic IOL
D. Aging population
A.Young
E. Dysfunctional lens syndrome
B. Moderate to high myope (US)
F. Increasing use of IOL-based procedures
C. Manageable astigmatism (US)
II. Basic Considerations
1. LRI (< 1.75 D)
2. Bioptics (> 1.75 D in healthy cornea)
A.Age
B. Needs (presbyope?)
D. Noncandidate for corneal refractive correction
C. Prior surgery?
E. Prefers optics
D. Manifest refraction
F. Clear lens
E. Keratometric values
F. Topographic pattern
A. Extreme keratometric values
G. Corneal exam
B. Post refractive
H. Lens exam
C. Consider “therapeutic” steepening or flattening
with staged IOL to balance induced refractive error.
D. Phakic IOL with moderate to high astigmatism
VII.Bioptics
I. Macular exam
III. Treatment Options
IV. Good Candidate for Corneal Correction
A. 50 or younger
B. Myope, plano presbyope, low hyperope
C. Intended correction and keratometry will not leave
a patient:
1. Too flat (myopic correction)
2. Too steep (hyperopic correction)
D. Normal topography
E. Healthy cornea
F. Clear lens
VIII.Summary
A. Contemporary refractive surgery includes corneal
and lens based procedures.
B. Patient selection is critical.
1. Risk factors
2.Optics
C. Improved understanding of candidacy
D. Improved technology
E. Emerging sub (sub)-specialty of presbyopia correction
148
Basics of Tomography and Topography
Marcelo V. Netto, MD, PhD
* No Financial Interest
Appropriate preoperative detection of corneal abnormalities is
an essential step in every refractive surgical procedure. Corneal
anatomical properties such as curvature and corneal thickness
must be carefully evaluated. Corneal topography and pachymetry are the most common exams performed prior to any surgical
procedure in the cornea.
Corneal topography based on the Placido Disk and corneal
pachymetry based on ultrasound have been used for many years
and are still considered the gold standard procedure. However,
additional information is now provided by corneal tomography
such as corneal thickness map, identification of the thinnest
point, posterior corneal curvature analysis and many different
softwares.
Corneal Pachymetry
It can be done using contact methods, such as ultrasound and
confocal microscopy (CONFOSCAN), or noncontact methods
such as optical biometry with a single Scheimpflug camera (such
as SIRIUS or PENTACAM), or a Dual Scheimpflug camera (such
as GALILEI), or Optical Coherence Tomography (OCT, such as
Visante) and online Optical Coherence Pachymetry (OCP, such
as ORBSCAN). Corneal Pachymetry is particularly essential
prior to laser surgery procedures for ensuring sufficient corneal
thickness to prevent abnormal bulging out of the cornea.
Newer generations of ultrasonic pachymeters work by way
of Corneal Waveform (CWF), capturing an ultra-high definition echogram of the cornea, somewhat like a corneal A-scan.
Pachymetry using the corneal waveform process allows the user
to more accurately measure the corneal thickness, verify the reliability of the measurements that were obtained, superimpose
corneal waveforms to monitor changes in a patient’s cornea over
time, and measure structures within the cornea such as micro
bubbles created during femto-second laser flap cuts.
Corneal Topography
Corneal topography—also known as videokeratography or
corneal mapping—represents a significant advance in the measurement of corneal curvature over keratometry. Most corneal
topographers evaluate 8,000 to 10,000 specific points across the
entire corneal surface.
Corneal toography methods are divided into three groups
according to the following optical principles:
• specular reflection, which includes the Placido disk system,
interferometry, and moiré deflectometry;
• diffuse reflection, which includes moiré fringes, rasterstereography, and Fourier Transform Profilometry;
• scattered light, which includes the slitlamp system.
Corneal topography instruments used in clinical practice most
often are based on Placido reflective image analysis and provide
some basic maps:
Axial map. Also called the “power” or “sagittal” map. It
shows variations in corneal curvature as projections and uses
colors to represent dioptric values.
Tangential map. Sometimes referred to as the instantaneous,
local, or “true” map, it also displays the cornea as a topographical illustration, using colors to represent changes in
dioptric value. However, the tangential strategy bases its calculations on a different mathematical approach that can more
accurately determine the peripheral corneal configuration.
It does not assume the eye is spherical, and does not have as
many presumptions as the axial map regarding corneal shape.
In fact it is the map that more closely represents the actual
curvature of the cornea over the axial map. The tangential
map recognizes sharp power transitions more easily than the
axial map, and eliminates the “smoothing” appearance that
appears on the axial map. Compared with axial maps, tangential maps yield smaller patterns with details that are more
centrally located. Tangential maps also offer a better visualization of the precise location of corneal defects.
Elevation map shows the measured height from which the
corneal curvature varies (above or below) from a computergenerated reference surface.
Refractive map This utilizes the measured dioptric power and
applies Snell’s law to describe the cornea’s actual refractive
power. A refractive map compensates for spherical aberrations as well as the aspheric contour of the cornea. The
central portion of the refractive map is most important. This
area overlies the pupil, so aberrations here almost invariably
impact visual performance.
Irregularity Map The irregularity map evaluate the cornea
surface and compare it to a best-fit ellipsoid, highlighting
surface irregularities (providing qualitative and quantitative
measurements) that may limit best-corrected visual acuity
Scaling is another important consideration with corneal
topography. In most topographers, the user can utilize the autosize or normalized scale (relative scale). This strategy essentially
subdivides the cornea into dioptric intervals based on its actual
curvature range (usually a 6.00D range). Recognize that the
actual colors are not specific to a dioptric value when using
the normalized scale, but rather are relative to that particular
patient’s eye. The absolute or standard scale assigns a specific
color to each dioptric value and constrains the data to fit within
that range. This strategy allows us to directly compare images
from different eyes or from significant curvature changes in one
eye.
Corneal Tomography
Orbscan
The Orbscan corneal topography system uses a scanning optical slit design that is fundamentally different from the corneal
topography that analyzes the reflected images from the anterior
corneal surface. The high-resolution video camera captures 40
light slits at the 45° angle projected through the cornea similarly
as seen during slit lamp examination. The instrument’s software
analyzes 240 data points per slit and calculates the corneal thickness and posterior surface of the entire cornea. The anterior
surface of the cornea initially was calculated in this manner;
however, since the calculation from the reflected images used by
corneal topography is more precise, the current version of Orbscan is using the latter method and is a combination of reflective
corneal topography and optical slit design.
The accuracy and repeatability of the instrument is reported
to be below 10 µm and, under optimal conditions, in the range
of 4 µm in the central cornea and 7 µm in the peripheral cornea. In clinical practice, it is even more dependent than corneal
topography on many factors, such as the limited movement of
the patient’s eye, ability of patients to keep the eye wide open,
optically clear cornea, and the presence of corneal abnormalities.
The other limitations of current optical slit technology are the
inability to detect interfaces (eg, after LASIK flap) and the longer
time of image acquisition and processing compared to standard
Placido-based topography.
Pentacam
The Pentacam (Oculus, Lynnwood, Wash) uses a different
method to image the cornea: Scheimpflug imaging. Scheimpflug
imaging is based on the Scheimpflug principle, which occurs
when a planar subject is not parallel to the image plane. In this
scenario, an oblique tangent can be drawn from the image, object
and lens planes, and the point of intersection is the Scheimpflug
intersection, where the image is in best focus. With a rotating
Scheimpflug camera, the Pentacam can obtain 50 Scheimpflug
images in less than 2 seconds. Each image has 500 true elevation
149
points for a total of 25,000 true elevation points for the surface
of the cornea.
The Pentacam actually has 2 cameras. One is for detection
and measurement of pupil, which helps with orientation and fixation. The second camera is used for visualization of the anterior
segment. The Pentacam is able to image the cornea such that it
can visualize anterior and posterior surface topography, including curvature, tangential, and axial maps.
Advantages of the Pentacam include the following: (1) high
resolution of the entire cornea, including the center of the cornea;
(2) ability to measure corneas with severe irregularities, such as
keratoconus, that may not be amenable to Placido imaging; and
(3) ability to calculate pachymetry from limbus to limbus.
The Belin / Ambrósio Enhanced Ectasia Display (BAD display) shows both anterior and posterior elevation data relative to
a standard best-fit-sphere (BFS) calculated at a fixed optical zone
of 8.0 mm.
Galilei
Galilei is another tomography system based on a revolving dualchannel Scheimpflug camera and a Placido Disk, performing corneal topography and three dimensional analysis of the anterior
eye. GALILEI™ combines two technologies: placido imaging for
curvature data and Scheimpflug imaging for capturing elevation
data.
The device captures slit images from opposite sides of the
illuminated slit, and averages the elevation data obtained from
corresponding opposite slit images. It’s main advantage is that
corresponding corneal thickness data from each view can simply
be averaged to compensate for unintentional misalignment.
150
Which IOL to Use?
I. Which patient?
3. “Distance and reading”
A. All are candidates (unless they are not!)
a.Books?
B. Patient temperament
b.Computer?
1.Best
a. Easygoing, realistic expectations
b. Hyperopic presbyopes
c. Significant cataract
2.Worst
a. Type AAA
b. Minimal cataract
c. Low myopes
II. Which eye?
A. Healthy eye!
1. Normalize ocular surface disease (dry eye, bleph)
2. Avoid macular disease, glaucoma
3. Avoid/treat anterior basement membrane dystrophy
4. Avoid eyes with prior refractive surgery
4. “Everything!” Reasonable patients are ok with
some glasses use. (Avoid the ones who aren’t.)
5. Make a recommendation.
IV. Which IOL? (FDA Approved)
A. Toric IOLS
1. Great “starter premium” for surgeon new to premium IOLs
2. Alcon Toric
3. STAAR Toric
B. Presbyopic IOLs
1. Astigmatism >0.5 D may affect visual acuity
(VA)
2. Can combine with astigmatism management as
confidence grows
a. Limbal relaxing incisions /on axis incision for
<1.5 D astigmatism
b. Laser vision correction later if >1.5 D if motivated patient
1.Monovision
a. Monofocal vs. toric IOL to achieve
b. Prior successful monovision
B. Spherical eyes for presbyopia IOLs at first
2.Accommodating
a. Options (FDA approved): Crystalens (Bausch
+ Lomb)
b.Strengths
i.Distance/intermediate
ii. Monofocal optic
1. Measures agree: Manual Ks match topo Ks (±
MRX cyl)
2. Start with lower astig. eyes (more forgiving)
III. What’s the goal?
A. Education: Patient may not know!
(b) Less contrast sensitivity reduction
i. Inconsistent near vision; readers often still
needed
(a) May improve with time/use
(b) Mini-monovision often used
ii. Lens position stability (Z syndrome)
3.Multifocal
1. Requires chair time from surgeon to educate re:
pros cons of each option
2. More education time up front = better expectations/success after
(a) Less halo/glare
c.Limitations
C.Astigmatism
a.Strengths
i. Distance / Near vision
ii. Most patients spectacle free
b.Limitations
i. All with some degree of halos/glare, contrast sensitivity loss
B. Zones of vision
1. “Glasses OK”
ii. Intermediate vision
2. “Distance, readers OK”
iii. Intolerant of small refractive errors
iv. Prolonged adaptation in some (“multifocal
blues”)
c. Options (FDA approved)
i. ReZoom (AMO)
ii. Tecnis Multifocal (AMO)
iii. ReSTOR (Alcon)
151
152
Managing LASIK Complications
Aylin Kılıc MD
I. LASIK Complications
A. The majority of complications occur intraoperatively.
3. Epithelial debris should be gently irrigated out
with BSS.
4. Long-term approach
B. Postoperative complications are almost always
related to events that occured during surgery.
II. Intraoperative Complications 1
a. Soft contact lenses
b. Gas-permeable contact lenses
c. Retreatment with LASIK 3-6 months later
if adequate thickness remains (deeper 20-60
microns)
d. PRK (high risk of haze and irregular astigmatism)
e. Complete flap removal with phototherapeutic
keratectomy
A. Incomplete flap/irregular flap
1. If the exposed stromal bed is not large enough to
allow adequate laser ablation:
a. Flap should be repositioned.
b. The laser procedure should be postponed.
c. Irrigation of the flap interface is performed.
2. Irregular cuts
a. The surgeon should not proceed with the
ablation.
b. The flap and fragments should be carefully
replaced and realigned.
c. Additional waiting/drying time
d. Bandage contact lens overnight
e. 3-6 months waiting
f. Deeper and more peripheral cut during the retreatment
1. When free cap is not visible on the surface of the
cornea, the microkeratome head should be carefully inspected.
2. If the diameter of the exposed stroma is equal to
or larger than the intended laser ablation zone,
laser treatment may proceed as planned.
4. Stromal adhesion should be ensured by allowing
adequate time of contact; 5-8 minutes should be
sufficient.
5. Sutures are seldom necessary.
6. Protection from potential for cap loss: wearing
eye shields at night, eyewear for sports
1. Flap is repositioned.
2. Operation repeated 10-12 weeks later
3. Deeper flap (20-60 microns deeper) may be
recut.
4. Alternatively, a no-touch transepithelial PRK
within 2 weeks, especially in low myopes
E. Corneal perforation (full-thickness anterior chamber entry)
1. Immediate closure of the cornea wound with
10-0 nylon sutures
2. Patient is asked to try to relax and minimize
coughing.
3. Transfer to operating room
4. Repair may involve corneal repair, iris repair,
lensectomy.
3. Replace with the epithelial side up and proper
orientation using high magnification.
B. Free flap
D. Thin/irregular flap
F. Epithelial defect/corneal erosions
1. Contact lens
2. Non-preserved artificial tear drops
3. Topical antibiotic
4. Nonsteroidal anti-inflammatory
G. Corneal limbus bleed
1. Apply a dry sponge to the bleeding area.
2. Leave the flap in position and wait until coagulation begins.
3. Pressurized air can be used as a vasoconstrictor
and to encourage coagulation.
4. In uncontrolled bleeding, the suction ring may be
reapplied and pressure reactivated for the duration of the ablation.
C. Thin flap/button holes
1. Avoid lifting the flap or immediately reposition
the flap.
2. Abort the procedure.
H. Inadequate suction
1. The result may be a thin or superficial flap, a
buttonhole or interrupted flap, or an irregular
flap.
2. If chemosis is induced from repeated suction
ring:
a. An incision in the conjunctiva may allow
drainage of excess fluid.
b. The handle of a swab can be used in an
attempt the fluid away from the limbus.
c. Alternative approach is to wait 30 to 45 minutes and then try again.
a. The use of the newer generation microkeratomes with down-up flap
b. By turning the head of the patient slightly to
the opposite side
c. By exerting a gentle pull and tilt on the eye
through the suction ring handle
d. Manual dissection can be considered.
e. PRK or LASEK should be considered if
appropriate.
1. If the area for ablation is adequate, the surgeon
may proceed with laser with a slight reduction in
the optical zone.
2. If the area for ablation is inadequate (important
in hyperopic and astigmatic treatments), the flap
is repositioned and the operation repeated in 3 to
4 months.
III. Femtosecond Laser Related
A. Epithelial gas breakthrough2
1. Don’t lift flap.
2. Postpone operation.
3. Wait 3-6 months.
B. Suction
1. Incomplete flap: second pass, recut
2. Same level flap
C. Opaque bubble layer4
loss3
1. Allow the opaque bubble layer to clear.
2. Recut deeper
IV. Postoperative Complications
A. Diffuse lamellar keratitis5
2. Daily follow-up
3. Oral corticosteroids
4. Flap lift and rinse interface with BSS
B. Flap striae6
1. Relift, refloat flap
2.Reposition
3. Flap traction with forceps or sponge
4. Hyperthermic treatment7
5.PRK8
C. Epithelial ingrowth
1. Lifting flap
2. Manual removal
3. Flap suturing
4. Topical corticosteroid
D. Interface debris/remnants
1. Flap elevation
2. Debris should be removed and irrigated as soon
as possible.
E. Dry eye9
f. Lateral canthotomy
I. Decentered flap
1. Intensive course of topical steroids
3. Inadequate exposure: Microkeratome placement
is difficult in sunken globes, in eyes with narrow
palpebral fissures and small corneas.
d. Postpone the procedure for 1 to 2 days and
allow the subconjunctival edema to reabsorb.
153
1. Artificial tear drop
2. Topical cyclosporine A
3. Punctal plug
F. Transient light sensitivity syndrome (TLSS)10
1. Use lower energy and faster femtolaser.
2. Intensive corticosteroids
3. Oral corticosteroids
References
1. Jacob JM, Taravella MJ. Incidence of intraoperative flap complications in laser in situ keratomileusis. J Cataract Refract Surg. 2002;
28:23-28.
2. Seider MI, Takeshi Ide T, Kymionis GD, Culbertson WW, O’Brien
TP, Yoo SH. Epithelial breakthrough during IntraLase flap creation
for laser in situ keratomileusis. J Cataract Refract Surg. 2008;
34:859-863.
3. Ide T, Yoo SH, Kymionis GD, Haft P, O’Brien TP. Second femtosecond laser pass for incomplete laser in situ keratomileusis flaps
caused by suction loss. J Cataract Refract Surg. 2009; 35:153-157.
4. Kaiserman I, Maresky HS, Bahar I, Rootman DS. Incidence, possible risk factors, and potential effects of an opaque bubble layer
created by a femtosecond laser. J Cataract Refract Surg. 2008;
34:417-423.
5. Cazorla RG, Teus MA, Llopis LB, Fuentes I. Incidence of diffuse
lamellar keratitis after laser in situ keratomileusis associated with
the ıntralase 15kHz femtosecond laser and Moria M2 microkeratome. J Cataract Refract Surg. 2008; 34:28-31.
6. Salomao MQ, Wilson SE. Femtosecond laser in situ keratomileusis.
154
7. Donnenfeld ED, Perry HD, Doshi S, Biser SA, Solomon R. Hyperthermic treatment of post-LASIK corneal striae. Cataract Refract
Surg. 2004; 30:620-625.
8. Kuo IC, Jabbur NS, O’Brien TP. Photorefractive keratectomy for
refractory laser in situ keratomileusis flap striae. J Cataract Refract
Surg. 2008; 34:330-333.
9. Golas L, Manche EE. Dry eye after laser in situ keratomileusis with
femtosecond laser and mechanical keratome. J Cataract Refract
Surg. 2011; 37:1476-1480.
10. Munoz G, Diego CA, Sakla HF, Javaloy J, Alio JL. Transient lightsensitivity syndrome after laser in situ keratomileusis with the femtosecond laser: incidence and prevention. J Cataract Refract Surg.
2006; 32:2075-2079.
155
Managing the Unhappy Refractive IOL Patient
David A Goldman MD
I. IOL Complaints
VIII. Z Syndrome Treatments
A. What are the most common complaints you hear in
your clinic after cataract surgery?
A. YAG capsulotomy should be maintained within the
optic of the IOL.
B. At least 90% of the patients who come in for second
opinion for dissatisfaction after cataract surgery =
unrealistic expectations.
B. In cases of Z syndrome, the capsulotomy can be
extended under the hinge.
C. Ocular irritation: itching, burning, foreign body sensation . . .
C. Post-capsulotomy, the symmetry can be restored by
placing 2 capsular tension rings in the bag.
D. Distorted vision: hazy, glare, haloes, filmy . . .
E. We’ll address the complaints associated with different IOLs.
D. In extreme cases of Z syndrome, may have to
exchange the lens. (If surgery done long ago, better
to amputate haptics.)
IX. YAG Anterior Capsulotomy
X. YAG Posterior Capsulotomy
1.Multifocal
2.Accommodating
II. Problem-Solving IOL Complaints
The most important factor is to address issues preoperatively:
A. Patients should understand the limitations of the
lens they’ve chosen.
B. Patients should be educated about predisposing risk
factors (pseudoexfoliation syndrome, Fuchs dystrophy, blepharitis)
III. What the Patient Thinks Will Happen
IV. Dissatisfaction With Accommodating Lenses
A. Limited reading ability
B.“Glare/haloes”
C.Z-syndromes
V. Limited Reading Ability
A. Operate dominant eye first
B. Check cycloplegic refraction
1. If plano target more myopia in nondominant eye.
2. If hyperopic, consider laser vision correction /
piggyback IOL or early YAG.
VI.Glare/Haloes
Many surgeons debate the need for atropine sulfate
after implantation of an accommodating IOL.
XI. Dissatisfaction With Multifocal IOLs
A.Glare/haloes
B. “Vaseline vision”
C. Need to check several factors (6 Cs described by
Eric Donnenfeld)
XII. Cylinder (Residual Astigmatism)
XIII. Can Correct With Limbal Relaxing Incisions or Laser
Vision Correction
XIV.LRICALCULATOR.COM
XV.Cornea
XVI. Tear film is an extremely important element with
respect to quality of vision.
XVII. Patients (without dry eyes) who were placed on cyclosporine for 2 weeks preoperatively and 3 months postoperatively had better quality of vision and more ocular
comfort.
XVIIII. Capsule
A. “Unremarkable” posterior capsule opacification can
be quite significant.
B. Caution: Avoid YAG if your gut is telling you the
patient will require an IOL exchange.
XIX.CME
XX.Centration
A. To avoid decentration, place haptics in superiorinferior orientation and nudge slightly nasally.
B. OK to center the lens on a pharmacologically constricted pupil, but this may not represent the true
physiologic pupil.
C. Can use light reflex.
VII. Z Syndrome
A. Not too common with AO models
B. Be wary of it in cases of increasing astigmatism with
regular topography.
C. Risk can be minimized by creating a large capsulorrhexis and ensuring both haptics are in the capsular
bag (lens should rotate easily).
XXI.Crazy?
A. Was I crazy to implant the lens in this patient?
156
B. Is the patient crazy?
C. May have to perform lens exchange
XXII. Last Resort IOL Exchange
XXIII.Summary
A. In all cataract surgeries: Success = Outcome –
Patient Expectations
B. Patients need realistic expectations set prior to surgery.
C. Postoperatively, make sure to listen to the patient’s
concerns and address them.
D. If in doubt, do not hesitate to recommend a second
opinion.
157
Refractive Lens Exchange
John Berdahl MD
Refractive lens exchange is a good option for patients whose
visual goals cannot be achieved through spectacles, contact lens,
phakic IOLs, or excimer photo ablation.1-3 Many patients are
not good candidates for these procedures for varying reasons,
such as dryness, unstable cornea, thin cornea, or inadequate
anterior chamber depth. As improvements in surgical technique,
IOL design, and IOL power calculation methods have improved,
refractive lens exchange has become a more common offering to
meet the needs and goals of our patients.
Refractive lens exchange is a particularly suitable option in
patients that are nonemmetropic and presbyopic. Hyperopia,
myopia, presbyopia, and astigmatism can all be treated with a
refractive lens exchange. Large amounts of astigmatism can be
fixed with a toric IOL, and smaller amounts can be corrected
with corneal relaxing incisions.4 Myopia and hyperopia can be
treated by choosing the properly powered IOL, and presbyopia
can be addressed with multifocal IOLs, accommodating IOLs,
or monovision.5,6 An additional advantage to refractive lens
exchange is the avoidance of future cataract surgery.
Refractive lens exchange is not without risk. Any intraocular
surgery puts the patient at risk for endophthalmitis, suprachoroidal hemorrhage, retained nuclear fragments, and other known
intraoperative and postoperative complications.
Advances in surgical technique—including small incisions,
better phacoemulsification technology, and femtosecond laserassisted cataract surgery,7-9 also known as refractive laserassisted cataract surgery (ReLACS)—have made cataract surgery, and by analogy refractive lens exchange, one of the safest
and most successful surgeries within all of medicine. Particularly
the advent of ReLACS has taken some of the most delicate steps
of surgery out of the surgeon’s hands, and it can be performed
with an unparalleled precision and reproducibility. (Conclusive
data have yet to be published that demonstrate clear superiority
and refractive outcomes with ReLACS.)
IOL designs such as multifocal, accommodating, toric,
and aspheric lenses allow the surgeon to match the IOL to the
patient’s visual goals. Diagnostic evaluation of the tear film,
topography, wavefront analysis, angle kappa, pupil size, refraction at varying optical zones, and spectral domain OCT allow
more precise customization of the surgery and IOL choice to
the patient’s anatomy. This customization becomes particularly
important in patients who have had prior refractive surgery or
who have high amounts of astigmatism.
IOL prediction methods have also improved considerably
with latest-generation formulas such as the Holliday 2 and Haigis, which take into account numerous variables and improve
our predictive capability. Better IOL formulas in combination
with intraoperative aberrometry10 have given surgeons very good
control over the postoperative refractive outcome.
Refractive lens exchange is a very familiar technique for any
cataract surgeon because there are very few differences. The only
major difference between refractive lens exchange and cataract
surgery is the softness of the lens. Traditional chop or divideand-conquer approach may not allow the surgeon to easily
divide the lens into segments. In soft lens situations, prolapsing
the lens into the anterior chamber and removing it with primarily aspiration is a good option. It is important to note that many
refractive lens exchange patients are younger and may have a
more robust healing response following refractive lens exchange.
This is important to the predictability of the effective lens position of the eye and also may affect the rate of posterior capsular
opacification (PCO) and capsular phimosis. Polishing the posterior and anterior surface of the capsule may help decrease the
rate of PCO and capsular phimosis in these patients. A special
word of caution about retinal detachments and high myopes is
warranted: A good peripheral retinal exam in addition to discussing the increased risk of retinal detachment in high myopes is
advisable.
Since refractive lens exchange is not yet able to achieve the
precision that comes with excimer photoablation (IOLs typically
come in half diopter powers and occasionally quarter diopter
powers), one should be cautious about performing a refractive
lens exchange in someone who would be a poor candidate for
excimer photoablation in the event that the refractive target is
missed. With the current advances in surgical technique, diagnostics, IOL design, and IOL prediction methods, refractive lens
exchange continues to be an important option in meeting the
refractive goals of our patients.
References
1. Nanavaty MA, Daya SM. Refractive lens exchange versus phakic
intraocular lenses. Curr Opin Ophthalmol. 2012; 23(1):54-61.
2. Koch DD. Refractive lens exchange: ethical considerations in
the informed consent process. J Cataract Refract Surg. 2005;
31(5):863.
3. Fine IH. Hoffman RS, Packer M. Refractive lens exchange: the
quadruple win and current perspectives. J Refract Surg. 2007;
23(8):819-824.
4. Ruiz-Mesa R, et al. Refractive lens exchange with foldable toric
intraocular lens. Am J Ophthalmol. 2009; 147(6):990-996, 996 e1.
5. Kashani S, Mearza AA, Claoue C. Refractive lens exchange for
presbyopia. Cont Lens Anterior Eye. 2008; 31(3):117-121.
6. Hoffman RS, Fine IH, Packer M. Refractive lens exchange with
a multifocal intraocular lens. Curr Opin Ophthalmol. 2003;
14(1):24-30.
7. Friedman NJ, et al. Femtosecond laser capsulotomy. J Cataract
Refract Surg. 2011; 37(7):1189-1198.
8. Mamalis N. Femtosecond laser: the future of cataract surgery? J
9. Nagy ZZ, et al. Comparison of intraocular lens decentration
parameters after femtosecond and manual capsulotomies. J Refract
Surg. 2011; 27(8):564-569.
10. Wiley WF, Bafna S. Intra-operative aberrometry guided cataract
surgery. Int Ophthalmol Clin. 2011; 51(2):119-129.
158
Phakic IOLs: Tips and Techniques
Thomas M Harvey MD
Phakic IOLs (P-IOLs) are currently FDA-approved for the treatment of myopia in the United States. The currently available
implants are (1) anterior chamber (iris fixated) AMO Verisyse
and (2) posterior chamber (sulcus positioned) Staar Visian ICL.
Recommendations below apply to the Visian ICL.
Patient Workup
• Obtain good manifest refraction (with known vertex distance)
• Obtain cycloplegic refraction (with known vertex distance)
• Perform contact lens overrefraction (disregarding vertex
distance)
• Plan for refractive astigmatism compensation
• Use objective white-to-white measurements (eg, IOLMaster)
• Consider ultrasound biomicroscopy for outlier anatomy
YAG Iridotomy
•
•
•
•
Schedule at least 10 days prior to P-IOL surgery
Consider upper eyelid position to avoid prismatic glare
Topical pilocarpine
Anesthetize with subconjunctival 2% lidocaine (without
epinephrine) using 30-gauge needle
• Iridotomy lens or no lens
• Initiate anti-inflammatory drops immediately
Topical/Intracameral Anesthetic Combination
• Consider avoidance of intracameral mydriatics if planning
surgical iridectomy
• Apply lidocaine 2% jelly or lidocaine gel 3.5% topical
after povidone iodine
• Inject preservative-free lidocaine 1% (intracameral)
P-IOL Management:
• Avoid hydroxypropylmethucellulose overfill
• Inject with cartridge lumen in anterior chamber (not
wound-assist)
• Consider cohesive ophthalmic viscosurgical device (OVD;
sodium hyaluronate) to maintain space between P-IOL
and endothelium and to avoid late IOP spikes
• Use angled paracentesis to best acquire footplates
Hoffer Vacuum Surgical Iridectomy
• Obtain good miosis (acetylcholine) – avoid intracameral
epinephrine/phenylephrine
• Keratotomy in reverse fashion toward angle
• Grasp anterior iris with small forceps
• Cut with iridectomy scissors
• Aspirate pigment epithelium with 25-gauge cannula
OVD Management
• Consider bimanual irrigation/aspiration with controlled
settings
• Administer oral acetazolamide as IOP prophylaxis
• Check IOP 1-2 hours after surgery
Same-Day Postoperative Check
• Mitigate early IOP spikes with sterile expression—topical
anesthetic plus povidone iodine 5%, 25-gauge needle with
or without eyelid speculum
• Use paracentesis instead of main wound to avoid sudden
decompression
• Complement with topical IOP agents, oral acetazolamide
Late Refractive Management
• Wait for stability in manifest refraction before any intervention
• Treat refractive cylinder only
• Consider PRK over LASIK if suspicious topography
Small-Incision Corneal Lenticule Extraction
Refractive surgery has evolved over the last two decades—from
surface ablation procedures to laser in situ keratomileusis. The
introduction of the femtosecond laser has reduced clinical complications and improved clinical outcomes. A natural evolution
in refractive surgery is the introduction of a complete stromalbased procedure without the use of a flap. Refractive lenticule
extraction (ReLEx) was introduced over 4 years ago and had
also evolved from a flap-based lenticule extraction to a small
incision–based procedure. Visual acuity and safety and efficacy
have been shown to be at least equivalent or superior to standard
femto-LASIK. The added benefit of no flap is being shown with
respect to nerve innervation and dry eye symptoms.
159
161
E-Poster Index—Innovations in Refractive Surgery
E-Posters will be available for viewing during the meeting, outside the session room, North Hall B, and after the meeting on the
Academy’s website: www.aao.org/2012.
Femtosecond Laser-Assisted Astigmatic Keratotomy for Naturally Occurring
Astigmatism
Ashkan M Abbey MD
168
Corneal and Internal Higher-Order Aberration Analysis of Femtosecond Laser
Refractive Lens Surgery
Ahmed A Abd El-Twab Abdou MD
168
Femtosecond Laser Refractive Lens Surgery Corneal Incision Anterior Segment OCT
and Corneal Higher-Order Aberration Analysis
Ahmed A Abd El-Twab Abdou MD
168
Differences in Corneal Thickness, Keratometric, and Keratoconic Indices Between
Scheimpflug Devices
Jihan Akhtar MD
169
Phakic IOLs: Intraocular Optical Quality Comparison of Angle-Supported, Iris
Fixated, and Posterior Chamber Lenses
Jorge L Alio MD PhD *
169
Outcomes of Laser Vision Correction in Myopes With Postoperative Corneal
Curvatures Less Than 37 D
Jella A An MD
169
Clinical Evaluation of a Presbyopic LASIK Algorithm in Post-LASIK Patients
Robert Edward T Ang MD *
170
Perforation After Collagen Crosslinking in Keratoconus
Mayte Arino MD
170
Optimized Femto-LASIK Maintains Pre-existing Spherical Aberration Independent of
Refractive Error
John D Au MD
170
Demographics and Ocular Characteristics of Patients Undergoing Screening for
Refractive Surgery
Sharmini A Balakrishnan MD
170
Stray Light Levels of Different IOL Designs and Materials
George Beiko FRCS *
171
Glistenings in Hydrophobic Acrylic IOLs: Are They Visually Significant?
George Beiko FRCS *
171
Reduced Cylinder With Femtosecond Laser-Assisted Cataract Surgery:
A Contralateral Eye Study
Sophia Bourdou RN
171
First Clinical Experience With a New Trifocal IOL
Detlev R Breyer MD *
171
Image Quality and Patient Comfort After Flapless Femtosecond Image Quality and
Patient Comfort After Flapless Femtosecond Laser Lenticule Extraction
Detlev R Breyer MD *
172
The Use of an Intraoperative Wavefront Aberrometer During Cataract Surgery in
Post-radial Keratotomy Eyes
Stephen F Brint MD *
172
Use of the Optical Quality Analyzing System to Assess Crystalline Lens Opacities in
Early Cataracts Lens Opacities in Early Cataracts
Florence Cabot MD
172
Spherical Aberration at Different Pupil Diameters Before and After Aspheric IOL
Implantation
Fabrizio I Camesasca MD *
172
Refractive Multifocal IOL With Rotational Asymmetry vs. an Apodized Diffractive
Multifocal IOLvs. an Apodized Diffractive Multifocal IOL
Pilar Casas de Llera PHD
173
Refractive Multifocal IOL With an Inferior Segmental Near Add vs. Diffractive
Multifocal IOL
Pilar Casas de Llera PHD
173
The Effect of Lighting Conditions On Near and Intermediate Visual Acuity With Two
Diffractive Multifocal IOLs
Daniel H Chang MD *
173
Quantitative Ectasia Risk Assessent Based on Clinical and Topographic Data
Rosane D Correa MD
173
Keratocyte Density After Microkeratome LASIK vs. Femtosecond Laser-Assisted LASIK
Laura de Benito-Llopis MD
174
162
E-Poster Index
The Impact of LASIK on Tear Film Osmolarity
Robert A Eden MD *
174
Rotationally Asymmetric Multifocal IOL: Optical Plate vs. C-Loop Design With and
Without Capsular Tension Ring
Amr M El Aswad MD
174
Combining Corneal Tomography and Biomechanical Parameters for Detection of Very
Mild Ectasia
Fernando Faria Correia MD
174
Comparison of IOL Calculation Methods and Intraoperative Wavefront in Eyes That
Have Undergone Refractive Surgery
Ana P Fraga Santini Canto MD
175
Preoperative and Postoperative Size and Movements of the Lens Capsular Bag:
Ultrasound Biomicroscopy Analysis
Sonu Goel DNB, MNAMS
175
Explore the Computer-Animated Model of Accommodation and Demystify Your
Understanding of Accommodation
Daniel B Goldberg MD
175
Combined Small-Incision Lenticule Extraction (SMILE) and Corneal Crosslinking in
Keratoconus: Preliminary Report
Enrique O Graue Hernandez MD
176
Potential Application of LipiFlow Thermal Pulsation System for Preoperative
Treatment of Dry Eye Signs and Symptoms
Jack Volker Greiner DO
176
Ocular Higher-Order Aberration Changes After Implantable Collamer Lens
Implantation for High Myopic Astigmatism
Seyed Javad Hashemian MD
176
Comparing and Evaluating the Anterior Chamber Depth by Ultrasound Biomicroscopy,
Orbscan II, and Lenstar in High Myopic and Keratoconic Eyes
177
Four-Year Outcomes With an Investigational Anterior Phakic IOL:
Multicenter Canadian Clinical Trial
Simon P Holland MD *
177
Clinical Performance and Patient Satisfaction After Implantation of New Multifocal
IOL: Soleko Fil 611pv
Claudio Iacobucci MD
177
High Myopia Outcomes With Latest-Generation Excimer Laser
Ananda Kalevar MD
178
Corneal Crosslinking and Long-term Hyperopic LASIK Stability:
Initial Clinical Findings in a Contralateral Eye Study
A. J Kanellopoulos MD *
178
Can Overall Corneal Epithelial Thickness Become a Very Early Ectasia Prognostic
Factor?
A. J Kanellopoulos MD *
178
Evaluation of Corneal Power Changes After Myopic Laser Refractive Surgery With A
New Scheimpflug Camera Device
Michele Lanza MD
178
Evaluation of Speed and Amplitude of Corneal Deformation in Naïve Eyes Utilizing
Oculus Corvis
Michele Lanza MD
179
New Use of Smartphones to Aid Patients With Postoperative Treatment Regimes and
Long-term Care
Nicola M Lau MBBS
179
Topography-Guided Photorefractive Keratectomy Using Allegretto Laser With
Simultaneous Crosslinking for Keratoconus
David Lin MD
179
Noninvasive Vision Correction: Refractive Index Changes in Cornea, Lens, and
Hydrogels With a High Rep Rate Femto Laser
Scott M MacRae MD *
180
Early Refraction and Visual Recovery Enhancement in Post Myopic PRK Eyes Using
Myopic Soft Contact Lenses
Scott M MacRae MD *
180
Corneal Collagen Crosslinking in Patients With Previous Unilateral or Bilateral
Radial Keratotomy
Parag A Majmudar MD *
180
Reliability of Central Pachymetry After Advanced Surface Ablation Using
Scanning-Slit Topography and Specular Microscopy
Miguel J Maldonado PhD
181
Implantable Collamer Lens Decreases the Dependability of Axial Length
Measurements Using Partial Coherence Interferometry
Miguel J Maldonado PhD
181
Femtosecond Laser-Assisted LASIK to Correct Medium to High Hyperopic Defects
Luigi Mosca MD
181
E-Poster Index
163
Pachymetric Parameters and Belin/Ambrosio Posterior Corneal Elevation to Diagnose
Sublinical Keratoconus
Orkun Muftuoglu MD
182
Relative Pachymetry and Asphericity After Myopic Excimer Laser Refractive Surgery
Orkun Muftuoglu MD
182
Correlation Between Pentacam HR Belin/Ambrosio Display Score and Ocular Response
Analyzer Keratoconus Match Score Index
Edwin W Nunnery BS
182
Comparison of Epithelial-On Crosslinking for the Treatment of Mild, Moderate,
Severe, and Extremely Steep Keratoconus
Gabriela Perez BS
182
Optical Quality in Myopic Patients Operated With PRK and FemtoLASIK Assessed by
Double-Pass Aberrometry
Eric Perez-Campagne MD
183
LASIK Enhancement Decision Making Aided by Sequential, Multioption Algorithm
Gaurav Prakash MD
183
A New, Pachymetry-Based Approach for Diagnostic Cutoffs for Normal, Suspects, and
Keratoconic Cornea
Gaurav Prakash MD
183
Keratoconus Classification Modeling Using Slit-Scanning Videokeratography
Mujtaba A Qazi MD *
184
Advanced Relational Thickness From Corneal Tomography for Enhanced Ectasia
Detection
Isaac O Ramos MD
184
Clinical Outcomes of PoClinical Outcomes of Posterior Chamber Implantable
Collamer Lenses and Iris-Fixated Phakic IOLs
Jagadesh C Reddy MD
184
Dual Scheimpflug Imaging Parameters in Post-LASIK Ectasia, Keratoconus, and
Normal Eyes
Jagadesh C Reddy MD
185
Visual Outcomes, Contrast Sensitivity, and Stereo Acuity After Corneal Presbyopic
LASIK in Emmetropic Patients
Dan Z Reinstein MD *
185
Spectral Domain OCT Analysis of Corneal Architecture and Epithelial Thickness
Profile in Corneal Collagen Crosslinking
Karolinne M Rocha MD PhD
185
Quantification of Refractive Error After IOL Implantation in Myopic Eyes and
Deviation of the Formulae
Alvaro Rodríguez Ratón MD
186
Evaluation of Epithelial-On Corneal Collagen Crosslinking in Young Patients
Roy Scott Rubinfeld MD *
186
Corneal Collagen Crosslinking in Patients With a Preop Diagnosis of Pellucid
Marginal Degeneration
Roy Scott Rubinfeld MD *
186
Results and Complications of Femtosecond Laser-Assisted Intrastromal Ring Implants
Over 4-Year Follow-up
Mahipal S Sachdev MD *
186
Distribution of Keratoconus Match Index and Keratoconus Match Probabilities in a
Normal Refractive Surgery Population
Youjia Shen MD
187
Surgical Efficiency of Femtosecond Laser Refractive Lens Surgery vs. Conventional
Phacoemulsification
Felipe A Soria MD
187
Study of Axial Length Before and After Myopic LASIK With the IOLMaster
Eugene Tay MBBS
187
OCT-Guided Femtosecond Laser Corneal Surgery
Minoru Tomita MD*
187
Intraoperative Power Selection and Axis Orientation of Toric IOL Using a Real-Time
Wavefront Aberrometer
Dan B Tran MD *
188
Evaluation of Epithelial-On Corneal Collagen Crosslinking in Older Patients
William B Trattler MD *
188
Evaluation of Epithelial-On Corneal Collagen Crosslinking in Patients With Previous
Intacs
188
Comparative Evaluation of PRK and LASIK for Vision Enhancement After
Implantation of Presbyopic IOL
188
Factors for Retreatment After LASIK: Three-Year Follow-up in a Hispanic Population
Jorge E Valdez-Garcia MD
189
Internal High-Order Ocular Aberrations After Implantation of a Toric IOL
Paolo Vinciguerra MD *
189
Microdistortions in Bowman Layer of Femtosecond Small-Incision Lenticule
Extraction: A Fourier Domain OCT Study
Peijun Yao MD
189
164
E-Poster Presenting Authors
Ashkan M Abbey MD
Sophia Bourdou RN
Miami Beach, FL
Athens, Greece
Laservision.gr Eye Institute
Miami, FL
Cataract and Cornea Research Fellow
Dusseldorf, Germany
Senior Surgeon
Breyer Eye Surgery
Assiut, Egypt
Lecturer, AUH, Egypt
Vissum Alicante, Spain
Jihan Akhtar, MD
Atlanta, GA
Resident
Emory University
Detlev R H Breyer MD
Stephen F Brint MD
Metairie, LA
Medical Director
Brint Custom Vision
Sonu Goel MBBS DNB
MNAMS(Ophtho)
Jaipur, Rajasthan India
Phaco-Refractive Surgeon
Anand Hospital And Eye Centre
Little Silver, NJ
Ophthalmology
Drexel College of Medicine
Jihan Akhtar MD
Florence Cabot
Atlanta, GA
Resident
Emory University
Montrabe, France
Jorge L Alio MD PhD
Milan, Italy
Istituto Clinico Humanitas, Milan - Italy
Mexico City, Mexico
Head, Cornea and Refractive Surgery
Instituto de Oftalmología, Fundación
Conde de Valenciana
Pilar Casas de Llera MD
Jack Volker Greiner DO PhD
Alicante, Spain
Ophthalmologist
Boston, MA
Clinical Instructor in Ophthalmology
Harvard Medical School
Daniel H Chang MD
Bakersfield, CA
Cataract & Refractive Surgeon
Empire Eye and Laser Center
Tehran, Iran
Rassoul Akram Hospital & Negah Eye
Center
Tehran University of Medical Sciences
Alicante, Spain
Miguel Hernandez University
Jella A An MD
Westmount, QC Canada
McGill University
Senior Ophthalmologist
Asian Eye Institute
Mayte Arino BMBS DOMS
Madrid, Spain
Consultant of Ophthalmology
University of Autonoma de MAdrid
John D Au MD
Cleveland Heights, OH
Resident
Cleveland Clinic Foundation
Ann Arbor, MI
Resident Physician in Ophthalmology &
Visual Sciences
Kellogg Eye Center
University of Michigan
George Beiko MD
St Catharines, ON Canada
Assistant Professor
McMaster University
Fabrizio I Camesasca MD
Rosane De Oliveira Correa
Rio De Janeiro, Brazil
In-training
London, United Kingdom
Ophthalmology Consultant
Vissum Madrid
Robert A Eden MD
Simon P Holland MD
Vancouver, BC Canada
University of British Columbia
Ferrazzano, Italy
Hospital Staff
Villa Esther-Boriano
Slingerlands, NY
Albany Medical College
Ananda Kalevar MD
Amr M El Aswad MD
Cairo, Egypt
Opthalmology
Vissum Corporacion
Athens, Greece
NYU Medical College
Fernando Faria Correia, MD
Michele Lanza MD
Porto, Portugal
Naples, Italy
Assistant Professor in Ophthalmology
Seconda Università di Napoli
Montreal, QC Canada
E-Poster Presenting Authors
Nicola M Lau MBBS
Gaurav Prakash MBBS
Youjia Shen MD
London, United Kingdom
Ophthalmology Registrar
Moorfields Eye Hospital, London
Abu Dhabi, United Arab Emirates
Consultant in Ophthalmology
Agarwals Eye hospital and Eye Research
Center
Montreal, QC Canada
McGill University
Mujtaba A Qazi MD
Alicante, Spain
Ophthalmologist
David T Lin MD
Vancouver, BC Canada
Clinical Assistant Professor , UBC
Pacific Laser Eye Centre
Scott M MacRae MD
Rochester, NY
Flaum Eye Institute University of
Rochester
Parag A Majmudar MD
South Barrington, IL
Rush University Medical Center
Miguel J Maldonado MD PhD
Valladolid, Spain
IOBA-University of Valladolid
Luigi Mosca MD
Rome, Italy
Adjunct Professor of Ophthalmology
Catholic University of “Sacro Cuore”
Orkun Muftuoglu MD
Ankara, Turkey
Ankara University School of Medicine
Edwin W Nunnery BS
Atlanta, GA
Medical Student
Emory University School of Medicine
Gabriela Perez
Miami, FL
Research Fellow
Center For Excellence In Eye Care,
Miami, FL
Eric Perez-Campagne
Paris, France
Fellow in Cataract and Refractive
Surgery
Chesterfield, MO
Director, Clinical Studies
Pepose Vision Institute
Isaac O Ramos, MD
Rio De Janeiro, RJ Brazil
Member of Rio de Janeiro Corneal
Tomography and Biomechanics Study
Group
Instituto de Olhos Renato Ambrosio
Jagadesh C Reddy MD
Philadelphia, PA
Cornea service
Wills Eye Institute
Dan Z Reinstein MD
London, England
Medical Director
London Vision Clinic, London, UK
Shaker Heights, OH
Cleveland Clinic Foundation - Cole Eye
Institute
Getxo, Vizcaya Spain
Resident in Ophthalmology
Hospital Galdakao - Usansolo
Roy Scott Rubinfeld MD
Chevy Chase, MD
Associate Clinical Professor of
Ophthalmology
Georgetown University Medical Center
New Delhi, India
Chairman & Medical Director
Centre for Sight Group of Eye Hospitals
165
Felipe A Soria MD
Eugene Tay FRCOphth
Singapore, Singapore
Consultant
Singapore National Eye Centre
Minoru Tomita MD
Tokyo, Japan
Executive Medical Director
Shinagawa LASIK Center
Dan B Tran MD
Long Beach, CA
Medical Director
Coastal Vision Medical Group
Miami, FL
Director of Cornea
Center For Excellence In Eye Care,
Miami, FL
San pedro Garza Garcia, NL Mexico
Dean
Escuela de Medicina Tecnológico de
Monterrey
Milan, Italy
Istituto Clinico Humanitas Rozzano
Peijun Yao MD
Shanghai, China
Attending Doctor Of Ophthalmology
Eye and ENT Hospital of Fudan
University
166
E-Poster Presenting Author Financial Disclosures
Ashkan M Abbey MD
Sophia Bourdou RN
Simon P Holland MD
None
None
Detlev R H Breyer MD
Alcon Laboratories, Inc.: L
Allergan: L
Bausch + Lomb: L
None
Carl Zeiss Meditec: C
Jihan Akhtar MD
Stephen F Brint MD
None
Alcon Laboratories, Inc.: C
WaveTec: C
Jorge L Alio MD PhD
Abbott Medical Optics: S
AcuFocus, Inc.: S
Akkolens: C,S
Alcon Laboratories, Inc.: S
Bausch + Lomb Surgical: C,S
Carl Zeiss Meditec: S
Hanita Lenses: C
Mediphacos: C
Novagali: S
Nulens: C,O;
Oculentis: C,S
Physiol: C
Presbia: C
Santen, Inc.: C
Schwind eye-tech-solutions: L,S
SLACK, Incorporated: C
Springer Verlag: P
Tedec Meiji: C
Tekia, Inc.: P
Thea: S
Topcon: C
Vissum Corp.: E,O
Florence Cabot MD
Jella A An MD
None
None
AcuFocus, Inc.: C,L
Allergan, Inc.: C,L;
Bausch + Lomb Surgical: C,L,S
Carl Zeiss Meditec: L
None
Fabrizio I Camesasca MD
Pilar Casas de Llera MD
None
Daniel H Chang MD
Abbott Medical Optics: C,L,S
Rosane De Oliveira Correa
None
None
Ananda Kalevar MD
None
Avedro: C
KeraMed, Inc.: L
WaveLight AG: L
Michele Lanza MD
None
Nicola M Lau MBBS
None
David T Lin MD
None
None
Scott M MacRae MD
Robert A Eden MD
AcuFocus, Inc.: C
Bausch + Lomb Surgical: C,L
Technolas : C
Allergan: L
Inspire Pharmaceuticals, Inc.: L
Amr M El Aswad MD
Fernando Faria Correia MD
None
None
Mayte Arino BMBS DOMS
Sonu Goel MBBS DNB
MNAMS(Ophtho)
None
None
John D Au MD
None
None
None
None
George Beiko MD
Jack Volker Greiner DO PhD
Abbott Medical Optics: C
None
None
Parag A Majmudar MD
Allergan, Inc.: C
Bausch + Lomb Surgical: C
Ista Pharmacuticals: C,S
Mobius Therapeutics: C
Rapid Pathogen Screening: O
Tear Science: C,S
Miguel J Maldonado MD PhD
None
Luigi Mosca MD
None
Orkun Muftuoglu MD
None
Edwin W Nunnery BS
None
Gabriela Perez BS
None
E-Poster Presenting Author Financial Disclosures
Eric Perez-Campagne MD
Roy Scott Rubinfeld MD
None
CurveRight: E,L,O,P
CXL USA: E,O
Allergan, Inc.: C,L,S
Aton Pharmaceuticals: C
Bausch + Lomb: S
CXLUSA: C
EyeGate: C
Inspire Pharmaceuticals, Inc.: C,L,S
Ista Pharmacuticals: S
LensAR: C
QLT Phototherapeutics, Inc.: C,S
Rapid Pathogen Screenings: S
Tear Science: C
Gaurav Prakash MBBS
None
Mujtaba A Qazi MD
Ista Pharmacuticals: L
TearScience: C
Isaac O Ramos MD
None
Jagadesh C Reddy MD
Abbott Medical Optics: C,L
Youjia Shen MD
None
Felipe A Soria MD
None
Eugene Tay FRCOphth
None
None
Minoru Tomita MD
Dan Z Reinstein MD
AcuFocus, Inc.: C
Zimmer: C
Arcscan, Inc., Morrison, Colorado: O,P
Dan B Tran MD
None
None
Alcon Laboratories, Inc.: C,L,O
ReVision Optics, Inc.: C,O
WaveTec Vision Systems, Inc.: C,O
None
Nidek, Inc.: C
Oculus, Inc.: C
Peijun Yao MD
None
167
168
E-Poster Abstracts
Innovations in Refractive Surgery
Femtosecond Laser-Assisted Astigmatic Keratotomy
for Naturally Occurring Astigmatism
Presenting Author: Ashkan M Abbey MD
Coauthors: Siamak Zarei-Ghanavati MD, Sonia H Yoo
MD, Ana P Canto MD, George D Kymionis MD, William W
Culertson MD
E-poster #: RP101495
Purpose: To evaluate the results of femtosecond laser-assisted
astigmatic keratotomy (FSAK) for naturally occurring high
astigmatism. Methods: Thirteen consecutive eyes from 9 patients
with naturally occurring high astigmatism who underwent
FSAK were included in the study. Measured parameters included
femtosecond laser settings, UCVA, BSCVA, manifest refraction, and corneal topography. Results: Mean follow-up was 9.8
months (range: 5 to 13 months). No intraoperative or postoperative complications were found. The mean surgically induced
subjective astigmatism change was 3.77 ± 1.28 D, which was
statistically significant (P < .001). The mean surgically induced
keratometric astigmatism change was 5.13 ± 3.13 D, which was
statistically significant (P < .001). The mean UCVA (logMAR)
was 0.85 ± 0.50 preoperatively and 0.24 ± 0.17 postoperatively.
The BSCVA remained stable or improved in 10 out of 13 eyes
(76.9%). There were no intraoperative or postoperative complications. Conclusions: FSAK is an effective and safe technique for
patients with naturally occurring high astigmatism. Comparative
studies will be needed to further elucidate its benefits in the treatment of astigmatism.
Corneal and Internal Higher-Order Aberration
Analysis of Femtosecond Laser Refractive Lens
Surgery
E-poster #: RP 101634
Purpose: To evaluate the changes in the postoperative corneal
higher-order aberrations (HOAs) and analyze the postoperative internal HOAs for femtosecond laser refractive lens surgery
(FLRLS) incision and IOL centration assessment. Method:
Prospective clinical study on 45 cataractous eyes operated with
FLRLS (27 MICS 1.8-mm and 18 minimal incision 2.2-mm
phacoemulsification). We assessed the efficacy of the incision
with corneal HOAs (6 mm) postoperative changes. The postoperative internal HOAs (4 mm) were also analyzed for IOL centration assessment. Both corneal and internal HOAs were analyzed using Hartmann-Shack aberrometer. Data was recorded
for 1 month of follow-up. Results: Mean age of patients was
68.9 ± 8.7 years; 40% males and 60% females. The means of the
preoperative corneal total HOAs for MICS and minimal incision
were 0.5 ± 0.1 µm, 0.7 ± 0.5 µm (P = .6), respectively. There was
no significant change in the postoperative corneal total HOAs
(6 mm) for both techniques and between the groups (0.5 ± 0.1
µm, 0.7 ± 0.2 µm; P = .2), but the corneal spherical aberration
of MICS was significantly less than the minimal incision after 1
month (-0.07 ± 0.2 µm, 0.2 ± 0.2 µm; P = .008). Internal third
HOA (4 mm) means of MICS and minimal incision were 0.26
± 0.30 µm, 0.13 ± 0.08 µm (P = .42), respectively, and internal
coma were 0.20 ± 0.23 µm, 0.10 ± 0.08 µm (P = .38) after 1
month of surgery. Conclusion: FLRLS incision does not affect
the corneal HOAs, with better results in MICS, and also ensures
good IOL centration. Larger data sample and longer follow-up
are recommended for more significant evaluation.
Femtosecond Laser Refractive Lens Surgery Corneal
Incision Anterior Segment OCT and Corneal HigherOrder Aberration Analysis
Purpose: To analyze the femtosecond laser refractive lens surgery
(FLRLS) corneal incision configuration and corneal higherorder aberration (HOA) effect from the first postoperative day.
Method: Prospective clinical study on 20 FLRLS-operated eyes.
The primary incision (tri-planar) actual length, cord length, surface angle, and regional pachymetry and the secondary incision
(uniplanar) length, angle, and pachymetry were analyzed (highresolution anterior segment OCT). Corneal HOAs were also
analyzed (Hartmann-Shack aberrometer). Data were recorded
for 1 month. Results: Mean age of patients was 72.2 ± 6.9 years;
35% males and 65% females. The actual length, cord length,
and surface angle means for the primary incision in the first postoperative day and month were 1.50 ± 0.1, 1.47 ± 0.2 mm (P =
.5), 1.41 ± 0.1, 1.42 ± 0.2 mm (P = .8), and 27 ± 4°, 23 ± 5° (P =
.07), respectively. The length and surface angle for the secondary incision in the first postoperative day and month were 1.17
± 0.01, 1.04 ± 0.1 mm (P = .05) and 52 ± 3°, 42 ± 5° (P = .007).
The regional pachymetry for the primary and secondary incisions
were significantly increased in the first postoperative day (preop
670 ± 41, postop 844 ± 94 µm; P < .001 and 664 ± 89, 779 ± 59
µm; P = .003), which were significantly decreased after 1 month
(731 ± 87 µm; P = .02, 673 ± 78 µm; P = .008). The tHOAs
were increased at the first postoperative day (preop 0.65 ± 0.45;
postop 0.90 ± 0.39 µm; P = .16) and then decreased after 1
month (0.69 ± 0.22 µm; P = .10). The spherical aberrations were
increased at the first postoperative day (preop 0.10 ± 0.3; postop
0.20 ± 0.3 µm; P = .3) and then decreased after 1 month (0.18 ±
0.2 µm; P = .8). Conclusion: The FLRLS incision is stable with
favorable results of the triplanar configuration. In the first postoperative month, corneal HOA change is unremarkable, which
could be related to restoration of corneal thickness.
Differences in Corneal Thickness, Keratometric, and
Keratoconic Indices Between Scheimpflug Devices
Presenting Author: Jihan Akhtar MD
Coauthors: James B Randleman MD, Sumitra Khandelwal MD
Purpose: To compare differences in corneal thickness and keratoconic indices between standard (Pentacam) and high-resolution
(Pentacam HR, Oculus, Inc.) Scheimpflug devices in patients
being evaluated for corneal refractive surgery. Methods: In eyes
with suspicious topographic patterns, consecutive eyes were
evaluated by both standard and HR Scheimpflug immediately
sequentially by the same technician. Indices analyzed included
front keratometry, back keratometry, central corneal thickness
(CCT) measurements, Keratoindex of surface variance (ISV),
index of vertical asymmetry (IVA), keratoconus index (KI),
central keratoconus index (CKI), minimum radius of curvature
(MRC), index of height asymmetry (IHA), and index of height
decentration (IHD). Results: Ninety eyes from 45 patients were
evaluated. All CCT values measured consistently thicker with
the standard Pentacam (CCT Center: 514.9 microns vs. 528.5
microns, P = .09; thinnest CCT: 512.8 vs. 528.5, P = .12, CCT
apex: 512.8 vs. 525.5, P = .08). Though not quite statistically
significant, there was a consistent trend. There were significant
differences in keratoconus index (P = .03) and central keratoconus index (P = .03). There was poor correlation between back
axis flat (r = 0.13), back K astigmatism (r = 0.19), keratoconus
index (r = 0.49), central keratoconus index (r = 0.57), index of
height asymmetry (r = 0.56), index of height decentration (0.27),
and minimum radius of curvature (r = 0.05). Conclusion: There
are clinically relevant differences and poor correlation between
some important screening indices when comparing standard and
HR Pentacam Scheimpflug devices. These devices may not be
interchangeable for LASIK screening or for following patients
after LASIK.
Phakic IOLs: Intraocular Optical Quality Comparison
of Angle-Supported, Iris Fixated, and Posterior
Chamber Lenses
Presenting Author: Jorge L Alio MD PhD
Coauthors: Ketevan Pachkoria PhD, Pablo Peña Garcia MS
Purpose: To evaluate the internal aberrometric profiles of eyes
implanted with phakic IOLs (P-IOLs). Method: 105 eyes of
67 patients were included in this retrospective study. The optical aberrations were measured with the aberrometer Topcon’s
KR-1W device. Three groups were formed according to the site
of P-IOL implantation: angle-supported anterior chamber (AC),
iris-fixated, and posterior chamber. Results: Angle-supported
rigid AC P-IOLs, Baikoff (ZB5M) revealed significantly higher
values of trefoil at 4-mm and 6-mm aperture diameter and internal total high-order aberration (HOA), third, coma, and tetrafoil
at 6 mm compared to the rest of the group. Baikoff (ZB5M) and
Kelman Duet have shown significant changes of spherical aberration from a negative to a positive sign from 4 to 6 mm; this trend
was not observed for the rest of the P-IOLs. In the group of irisfixated P-IOLs, significant differences were achieved comparing
Artiflex (Abbot Medical Optic) (0.32 ± 0.13 µm) with Artisan
(Opthec BM) (0.49 µm ± 0.26) P-IOLs in third internal aberration at 6 mm (P = .03, Mann-Whitney U test). In the group of
posterior chamber P-IOLs, significant differences were found
E-Poster Abstracts
169
comparing ICL (Staar Surgical Co) (0.05 ± 0.02 µm) with PRL
(Medennium Inc.) (0.11 ± 0.07 µm) P-IOLs in coma aberration
at 4 mm (P = .03, Mann-Whitney U test). Conclusions: The Baikoff (ZB5M), Artisan (Opthec BM), and PRL (Medennium Inc.)
revealed a worse internal aberrometric profile than the rest of the
group. The study of intraocular optics is an excellent method to
identify the best P-IOLs in terms of intraocular optical behavior.
Outcomes of Laser Vision Correction in Myopes
With Postoperative Corneal Curvatures Less Than
37 D
Presenting Author: Jella A An MD
Coauthors: Eser Adiguzel PhD, Mark Cohen MD, Avi
Wallerstein MD
Purpose: To determine the efficacy, accuracy, safety, stability,
and satisfaction of laser vision correction (LVC) in myopes with
postop keratometry less than 37 D. Methods: Retrospective
chart review of myopes undergoing LVC with postop keratometry (K) of less than 37 D. Postop manifest refractive spherical
equivalent (MRSE), cylinder, uncorrected distance VA (UDVA),
corrected distance VA (CDVA), maximum K (Kmax), and minimum K (Kmin) were compared to preop. A standardized, subjective quality of vision questionnaire was administered 6 months
postoperatively. Repeated-measures ANOVA and Holms Sidak
post-hoc tests were used. Results: Eighty identified eyes had a
mean attempted MRSE correction of -8.31 ± 1.55 D (range:
-5.13 to -11.25 D). Preop Kmax was 43.2 ± 1.4 D (range: 41 to
46 D) and Kmin was 42.0 ± 1.5 D (range: 39 to 45 D), postop
Kmax of 36.2 ± 0.84 D (range: 33.6 to 36.9 D) and Kmin of 35.5
± 0.83 D (range: 33.0 to 36.8 D). Cumulative UDVA of 20/20,
20/25, 20/30, and 20/40 or better in 69, 85, 95, and 100% of
eyes, respectively, compared to preop cumulative CDVA of 78,
93, 99, and 100%, respectively. Fifty-nine percent, 74%, and
97% of eyes were within ±0.25, ±0.50, and ±1.00 D of target
postop refraction (R2 = 0.905). Only loss of Snellen lines of
CDVA was in 1 eye with 1-line loss. Postop MRSE was stable,
with no significant differences by 6 months, or later timepoints
(P = .11). 100% of respondents rated their quality of vision as
better than preop and their uncorrected quality of vision as 9.4 ±
0.8 (on a scale of 1-10) compared to preop corrected 8.3 ± 1.1.
Conclusion: LVC in moderate to high myopia with resultant
postop K values of less than 37 D has outcomes comparable to
those in the literature for eyes without flat Ks. Postop subjective
quality of vision was excellent. Predicted flat keratometry postop
should not be a preop criterion of exclusion for LVC.
170
E-Poster Abstracts
Clinical Evaluation of a Presbyopic LASIK Algorithm
in Post-LASIK Patients
Presenting Author: Robert Edward T Ang MD
Purpose: A prospective clinical investigation to evaluate the
safety and efficacy of a presbyopic LASIK algorithm for treating post-LASIK patients. Methods: In this single surgeon, single
centre study, post-LASIK patients were selected to undergo a
monolateral presbyopic (Supracor algorithm) LASIK treatment.
All presbyopic LASIK procedures were performed using the
Technolas 217P Excimer laser. Patients were monitored over a 6
month follow-period. Safety, efficacy, predictability, uncorrected
distance, intermediate and near visual acuity (UDVA, UIVA,
UNVA), best correct distance visual acuity (BSCVA) and a subjective patient questionnaire were measured. Target refraction
was -0.5D. Results: To-date, 11 patients have undergone the procedure. Mean patient age was 51.2 years. Pre-operatively, mean
refractive spherical equivalent (MRSE) was +0.16D. At 3 months
post-operatively, MRSE was -0.31D. Monocular UDVA of 0.8
increased from 81% to 100% of eyes. Monocular UIVA of 0.8
improved from 75% to 100% of eyes. Monocular UNVA of 0.8
improved from 9% to 100% of eyes. No patient lost more than
1 line of monocular BSCDVA. A patient questionnaire found all
patients found the procedure provided results according to their
expectations. Conclusion: Early outcomes indicate the presybopic LASIK algorithm is safe and effective in the treatment of
post-LASIK patients improving vision at all distances.
Perforation After Collagen Crosslinking in
Keratoconus
Presenting Author: Mayte Arino MD
Coauthors: Simon P Holland PhD, Martin J McCarthy PhD,
Gregory Moloney MD
Purpose: To evaluate risk factors and develop recommendations
to avoid complications. Study Design: Four charts were retrospectively reviewed. Methods: Medical history, preoperative
pachymetry and keratometry readings, and postoperative treatment were analyzed. Results: Three patients had thin corneas,
including 1 whose pachymetry was lower than 400 microns prior
to the de-epithelialization. Topical voltaren was used in 2 of the
patients. Three patients underwent penetrating keratoplasty.
Two patients gained vision. Conclusions: Collagen crosslinking
is a new therapeutic approach to prevent progression of keratoconus. It is not exempt of sight-threatening complications. Following the standards previously described is recommended.
Optimized Femto-LASIK Maintains Pre-existing
Spherical Aberration Independent of Refractive
Error
Presenting Author: John D Au MD
Coauthor: Ronald Krueger MD
Purpose: We wish to report the visual outcome and change in
spherical aberration in the first cohort of eyes treated with wavefront-optimized femto-LASIK using the WaveLight Allegretto
Wave EyeQ and FS200 lasers. Methods: A retrospective chart
review was performed on patients undergoing refractive correc-
tion using the Allegretto Wave Eye Q excimer laser and FS200
femtosecond lasers between 3/2011 and 3/2012. Optimized
Femto-LASIK was targeted for emmetropia in 74 eyes and subdivided into mild (< -3.0 D), moderate (-3.1 to -6.0 D), and high
myopia (> -6.0 D). Preop and > 3 postop measures of UCVA and
wavefront aberrometry were recorded and compared between
groups and in reference to previous wavefront-guided intraLASIK outcomes. Results: A 20/15 and 20/20 UCVA was achieved
in 24% and 82% of eyes with mild myopia (17 eyes), 35% and
97% with moderate myopia (34 eyes), and 17% and 80% with
high myopia (18 eyes), respectively. The mean change in spherical aberration at a 5.5-mm pupil was +0.03 μm (±0.02 μm, P =
.23) for low myopia, +0.002 μm (±0.009 μm, P = .98) for moderate myopia, and -0.001 μm (±0.02 μm, P = .66) for high myopia.
The mean change in coma was +0.03 μm (±0.02 μm, P = .32) in
low myopes, +0.002 (±0.02, P = .09) in moderate myopes and
-0.002 (±0.04, P = .01) in high myopes. Conclusions: Wavefrontoptimized femto-LASIK with the WaveLight Allegretto Wave
EyeQ and FS200 lasers achieves excellent postop UCVA outcomes in this initial surgical experience with this platform, and
with no significant induction of spherical aberration at all refractive errors. It maintains the natural aspheric shape of the cornea
by the placement of additional pulses in the midperiphery to
compensate for the cosign effect in the angle of incidence of laser
pulses.
Demographics and Ocular Characteristics of Patients
Undergoing Screening for Refractive Surgery
Presenting Author: Sharmini A Balakrishnan MD
Coauthors: David C Musch PhD MPH, Maria A Woodward
MD
Purpose: To compare preoperative demographic and refractive
characteristics of patients approved for laser refractive surgery
who do or do not elect to proceed with surgery. Methods: Retrospective chart review of 700 patients screened for refractive
surgery at the Kellogg Eye Center from 2009 to 2011. Patient
information collected included demographic data on age, gender, primary language, and ethnicity and ophthalmic data on
visual acuity, refractive error, keratometry values, and pupil size.
Exclusion criteria included insufficient chart documentation and
approval for nonlaser forms of refractive surgery. Chi-square
tests and analysis of variance were performed for statistical
analysis. Results: A higher percentage of myopic patients elected
surgery compared to hyperopic and astigmatic patients (P = .003
O.D., P = .005 O.S.). There was a statistically significant difference in mean spherical equivalent of patients proceeding with
or declining surgery (-3.40 ± 2.66 vs. -2.65 ± 3.03 O.D., -3.50 ±
2.60 vs. -2.66 ± 3.01 O.S., P < .05, respectively). There was no
statistical difference in surgery rate between mild to moderate
myopes and high myopes (P > .10). Patients who proceeded with
surgery were younger on average (37.1 ± 10.5 vs. 39.0 ± 11.3,
P = .05). Conclusions: Younger patients with myopia are more
likely to proceed with refractive surgery. Other demographic and
refractive characteristics did not play a substantial role in decision making for electing surgery.
E-Poster Abstracts
171
Stray Light Levels of Different IOL Designs and
Materials
Reduced Cylinder With Femtosecond Laser-Assisted
Cataract Surgery: A Contralateral Eye Study
Presenting Author: George Beiko FRCS
Presenting Author: Sophia Bourdou RN
Purpose: To determine stray light levels for IOLs with different
designs and materials. Methods: The stray light levels of IOLs
made from 3 different materials and 3 different designs were
compared. The IOLs were measured on an optical bench in an
eye model. These graphs were compared to a 20- and a 70-yearold human crystalline lens. Results: The stray light levels of all
monofocal lenses were below or comparable to the levels measured for a 20-year-old human crystalline lens. Hydrophobic
acrylic monofocal aspheric lenses have lower stray light levels
than monofocal spherical lenses. The stray light levels for monofocal lenses made from silicone were higher than values for lenses
from hydrophobic acrylics. Typical values for the stray light of
aspheric monofocal lenses at 2 degrees vary from 1.0 to 2.6,
while the stray light for a healthy 20-year-old crystalline lens is
3.42. Acrylic diffractive multifocal stray light levels are between
that of a 20-year-old and a 70-year-old healthy human crystalline lens. Conclusion: IOLs made from hydrophobic acrylics
have similar design-dependent stray light levels, with multifocal
IOLs having the highest stray light levels, followed by monofocal
spherical IOLs. Monofocal aspheric IOLs have the lowest stray
light levels. Silicone lenses have higher straylight levels than comparable hydrophobic acrylic lens designs. All lenses tested have
stray light levels lower than that of a 70-year-old healthy human
crystalline lens for a forward scatter measured between 0.6 and
2 degrees.
Coauthor: A John Kanellopoulos MD
Glistenings in Hydrophobic Acrylic IOLs: Are They
Visually Significant?
Presenting Author: Detlev R Breyer MD
Presenting Author: George Beiko FRCS
Purpose: To assess image quality in hydrophobic acrylic IOLs
with microvacuoles. Methods: Microvacuole formation was
induced using an in vitro process by immersion in saline. The
microvacuoles were analyzed using dark field photos and a
confocal microscope. Modulation transfer function (MTF) and
straylight scatter were measured on an optical bench. Results:
Confocal images will be presented. Microvacuoles had no effect
on MTF. All lenses without microvacuoles have straylight levels
lower than a 20-year-old healthy human lens; lenses with glistenings have straylight levels greater than a 20-year-old lens. Multifocal lenses with glistenings have straylight levels approaching
that for a 70-year-old human lens. Conclusion: Microvacuoles
in hydrophobic acrylic IOLs increase straylight levels and can
impact adversely on visual performance.
Purpose: To evaluate the short- and longer-term visual recovery
of eyes treated with femtosecond laser-assisted cataract surgery
(FACS) or blade incision. Methods: In a randomized eye assignment, 14 consecutive bilateral cataract cases had wither FACS
(Group A) or manual keratome (Group B). Both groups had 2.8mm incisions. All cases were evaluated prior to and following
their surgery using refraction, visual acuity, automated keratometry, endothelioscopy, corneal topography, Scheimflug tomography, and IOP. Mean follow-up time was 3 months (3-12) postsurgery. Results: Mean refractive astigmatism was more stable
in Group A, while it was more variable (decreasing over the very
short term) in the eyes of Group B. Keratometric astigmatism in
the same time period showed a similar effect, with mean cylinder
change at 3 months of 0.12 D in Group A and 0.48 D in Group
B (P < .0001), indicating that the refractive effect was related
to differences observable on the anterior cornea. Topographic
asymmetry was evident in eyes of Group B. Conclusions: FACS
may improve wound integrity following small-incision cataract
surgery. The evidence here suggests that postoperative stabilization of the refraction occurs sooner, providing advantage in
terms of patient and surgeon perception of the success of the
surgery.
First Clinical Experience With a New Trifocal IOL
Coauthors: Hakan Kaymak MD, Karsten Klabe MD, Franziska
Dillner PhD
Purpose: Presbyopia and refractive errors are successfully treated
with multifocal IOLs after cataract surgery. Drawbacks of these
bifocal IOLs are (1) there are only 2 effective foci (far and intermediate or near vision) and (2) possible photopic phenomenons
like halo and glare. We present our first clinical results. Methods:
This is a prospective study of 10 eyes where we implanted a trifocal, aspheric IOL binocularly to correct presbyopia after cataract
surgery. Subjective refraction and a defocus curve were done for
evaluation of visual acuity in different distances. A patient questionnaire was also conducted to assess halo and glare. Results:
Implantation of the trifocal IOL resulted in far and near vision
that was comparable to or better than conventional bifocal IOLs
and also improved intermediate visual acuity. Patients, astonishingly, mentioned less photopic phenomena. Conclusions:
Because of very good near, intermediate. and far vision this new
trifocal IOL became a routine procedure for our patients with
the desire to achieve spectacle-free vision. We also recommend
them to night drivers as well.
172
E-Poster Abstracts
Image Quality and Patient Comfort After Flapless
Femtosecond Laser Lenticule Extraction
Presenting Author: Detlev R Breyer MD
Coauthors: Hakan Kaymak MD, Karsten Klabe MD, Franziska
Dillner PhD
Purpose: It is possible to correct refractive errors with femtosecond laser-assisted small-incision lenticule extraction (SMILE)
without creating a flap. We report about our first results of the
new flapless technique to evaluate postoperative image quality
and patient comfort with a questionnaire. Fifty patients were
examined. Methods: We used the femtosecond laser VisuMax
(CZM) for lenticule preparation. Postoperative aberrometry was
documented with the Topcon KR-1W aberrometry. A crosssection of the anterior eye segment was done by the Visante OCT
(CZM). Patients had to complete a questionnaire. Results: Visual
acuity after the SMILE technique was retarted in comparison to
conventional femtoLASIK; nevertheless, patients reach a minimum of 0.0 logMAR 1 month postoperatively. Less dry eye and
pain was reported after the SMILE procedure in comparison to
LASIK. Conclusions: Due to good efficiancy and safety, SMILE
is the method of choice when treating patients with myopic
refractive errors. A bigger patient group has to be evaluated in
the near future to achieve statistically more significant results.
The Use of an Intraoperative Wavefront
Aberrometer During Cataract Surgery in Post-radial
Keratotomy Eyes
Presenting Author: Stephen F Brint MD
Eyes that have had previously undergone a radial keratotomy
(RK) are notoriously difficult to achieve an accurate IOL calculation on prior to cataract surgery. We sought to determine if the
use of an intraoperative wavefront aberrometer improved refractive outcomes when used to perform an aphakic IOL power
calculation.
Use of the Optical Quality Analyzing System to
Assess Crystalline Lens Opacities in Early Cataracts
Presenting Author: Florence Cabot MD
Coauthors: Alain Saad MD, Colm McAlinden PhD, Nour Maya
Haddad MD, Alic Grise-Dulac MD, Damien Gatinel MD
Purpose: To assess correlations between visual acuity, optical quality analyzing system OQAS (Optical Quality Analysis
scores, patient discomfort, and type and severity of age-related
cataract. Methods: Propective monocenter study including
patients referred for cataract evaluation. Patients having other
pathologies impairing ocular transparency were excluded. Participants completed a quality of vision questionnaire. Assessment
of lens opacification by the Lens Opacities Classification System
III (LOCS III) and maximal contrast BCVA were performed.
The OQAS measurements provided ocular modulation transfer
function (MTF) cut-off frequency and ocular scatter index (OSI).
Three groups of patients were analyzed: visual acuity groups,
cataract groups, and functional symptoms groups. Results: We
included 253 eyes of 135 patients. In patients with BCVA superior to 0.2 logMAR, we found correlations between OSI, MTF,
and visual acuity (r = 0.4, P < .0001). The OSI, the MTF, and the
visual acuity were correlated in every type of cataract considered.
In patients with a good visual acuity and moderate functional
symptoms, the OSI values were also correlated to the severity of
posterior subcapsular cataract (r = 0.4; P = .0006). Conclusions:
We found correlations between the OQAS measurements and
the visual acuity of patients in all types of cataract. Correlations
were found between the OSI values and the severity of posterior
subcapsular cataract. Patients presenting with incipient cataract
might complain of visual discomfort despite minor lens opacity
at slitlamp examination and/or minor loss of BCVA. The measurement of ocular scattering by the OQAS device might be a
useful tool in the preoperative evaluation of patients presenting
early cataract.
Spherical Aberration at Different Pupil Diameters
Before and After Aspheric IOL Implantation
Presenting Author: Fabrizio I Camesasca MD
Coauthors: Mario Romano MD, Massimo Vitali, Orthoptist
Purpose: To prospectively evaluate the total, corneal, and internal ocular spherical aberration (SA) before and after implantation of SN60WF, an IOL with an aspheric posterior surface and
a negative mean Z(4,0) of -0.20 µ, at different pupil diameters.
Methods: All eyes underwent complete ophthalmological examination and high-order aberrations (HOA) evaluation under
mesopic conditions with Nidek OPD aberrometer preoperatively
and 1 month after surgery. Wavefront aberrations were reconstructed using third through sixth order Zernike polynomial
decompositions for a 3-, 4-, and 5-mm pupil. Results: Sixty-three
eyes of 46 patients (mean age, 71.41 ± 9.85) underwent uneventful cataract surgery with topical anesthesia and insertion of an
Alcon SN60WF aspheric IOL through a 3.2-mm incision. Mean
IOL power was +20.38 ± 4.03 D (range: +29.50 D to +9.00D).
Mean follow-up period was 19.90 ± 9.40 days. Corneal SA
remained unchanged. Internal SA remained unchanged for a
3-mm pupil (from 0.04 ± 0.03 µ to 0.03 ± 0.02 µ), decreased
significantly for a 4-mm pupil (from 0.13 ± 0.16 µ to 0.08 ± 0.06
µ), and remained unchanged for a 5-mm pupil (from 0.28 ± 0.23
µ to 0.26 ± 0.24 µ). Postoperative UCVA was 0.73 ± 0.29, and
BSCVA was 0.92 ± 0.19 with -0.14 ± 1.19 sph, -0.62 ± 0.59 cyl
(-0.43 ± 1.17 SE). Conclusions: Insertion of this aspheric IOL
decreased internal SA for a 4-mm pupil, bringing its total value
toward normal, noncatararactous eye values. Smaller or larger
pupil measurements showed no decrease in internal SA.
E-Poster Abstracts
173
Refractive Multifocal IOL With Rotational
Asymmetry vs. an Apodized Diffractive Multifocal
IOL
lighting, the full diffractive multifocal IOL provides better NVA
and IVA than the apodized diffractive multifocal IOL.
Presenting Author: Pilar Casas de Llera PHD
Quantitative Ectasia Risk Assessent Based on Clinical
and Topographic Data
Coauthors: Ana Belen Plaza Puche MS, Jorge L Alio MD PhD,
Jaime Javaloy PhD, Maria Jose Ayala MD
E-poster #:RP101572
Purpose: To compare the visual outcomes with a rotational
asymmetric multifocal IOL (MIOL) and an apodized diffractive
MIOL. Methods: Seventy-five eyes were divided into 2 groups:
zonal Group A—39 eyes with the Lentis Mplus LS-312 IOL, and
Group B—35 eyes with the ReSTOR SN6AD3. Results: Uncorrected and distance-corrected near visual acuity were better in
Group B (P = .01). Intermediate acuity (defocus +1.0 and +1.5 D)
and contrast sensitivity were better in Group A (P = .04). Conclusions: The Lentis Mplus LS-312 IOL provided better results in
contrast sensitivity and intermediate vision, while the ReSTOR
SN6AD3 provided better near vision at a closer distance.
Refractive Multifocal IOL With an Inferior Segmental
Near Add vs. Diffractive Multifocal IOL
Presenting Author: Pilar Casas de Llera PhD
Jaime Javaloy PhD, Maria Jose Ayala MD
Purpose: To compare the visual outcomes with a multifocal IOL
with an inferior segmental near add or a diffractive multifocal
IOL. Methods: Eighty-three eyes were divided into 2 groups:
Group A—45 eyes with Lentis Mplus LS-312, and Group B—38
eyes with Acri.Lisa 366D IOL. Results: Better uncorrected
near VA and distance corrected near VA (P = .04) were found
in Group B. Better intermediate visual acuities were present in
Group A (P = .04). Better values were observed contrast sensitivity in Group A (P = .04). Conclusions: The Lentis Mplus LS-312
provided better intermediate vision and contrast sensitivity, and
the Acri.Lisa design provided better distance and near visual
outcomes.
The Effect of Lighting Conditions On Near and
Intermediate Visual Acuity With Two Diffractive
Multifocal IOLs
Presenting Author: Daniel H Chang MD
Purpose: Near visual acuity (NVA) and intermediate visual acuity (IVA) can be affected by lighting conditions as well as the diffractive multifocal IOL design. Methods: Prospective evaluation
of NVA and IVA in photopic and mesopic lighting conditions
was done on 49 eyes with either a full-diffractive multifocal
IOL or an apodized diffractive multifocal IOL. Results: For
near, photopic distance-corrected NVA was 20/23 for the fulldiffractive multifocal IOL and 20/31 for the apodized diffractive
multifocal IOL (P = .001); mesopic distance-corrected NVA
was 20/30 and 20/37 (P = .046) for the 2 IOLs, respectively. For
intermediate, photopic distance-corrected intermediate VA was
20/34 and 20/46 (P = .002) for the 2 IOLs; mesopic distance-corrected intermediate VA was 20/47 and 20/58 (P = .016) for the 2
IOLs. Conclusion: Mesopic lighting can decrease NVA and IVA
by approximately a line of vision. In both photopic and mesopic
Presenting Author: Rosane D Correa MD
Coauthors: Renato Ambrosio Jr MD, Jorge Siqueira MD, Isaac
Ramos MD, Fernando Correia MD, Marcella Salomao MD,
Bruno Valbon MD, Bernardo Lopes MD, Ana Laura Canedo
MD, Frederico Guerra MD, Rodrigo Santos MD
Purpose: To develop and test a quantitative score for assessing
ectasia risk based on clinical and topographic (front surface
curvature) parameters. Methods: Preoperative age, spherical
equivalent (SE), residual stromal bed (RSB), central corneal
thickness (CCT), subjective classification of corneal topography,
and an objective topometric indices from Pentacam HR (Oculus)
from 23 cases that developed ectasia after LASIK and from 266
cases that had documented stability with minimal follow-up of
1 year were compared. Classic ERSS (Ectasia Risk Score System)
was calculated. Fisher’s linear discriminant analysis (LDA) was
used for finding linear combinations of the analyzed parameters
that best separates the cases that developed ectasia and the ones
with stable LASIK outcomes. The areas under the ROC curve
(AUC) were calculated, and pairwise comparisons were accomplished (De Long’s method). Results: Classic ERSS had 47.82%
(11/23) and 18.05% (48/266) of false negatives and false positives, respectively. The LDA function-1 included clinical parameters (age, SE, CCT, and RSB) and the subjective topographic
score, achieving AUC of 0.952 (sensitivity = 91.3%, specificity
= 93.23%; 95% CI, 0.921-0.974). LDA function-2 considered
clinical parameters and the objective topometric index IHD
from Pentacam (index of height decentration), having AUC of
0.980 (sensitivity = 100%; specificity = 93.23%; 95% CI, 0.9570.993), which was significantly better than LDA function-1.
Conclusion: Linear combinations of quantitative clinical para
meters were significantly better than qualitative score system in
this series. Objective topometric parameters were superior than
subjective classification of corneal topography as a quantitative
metric to improve LDA. Validation studies are necessary.
174
E-Poster Abstracts
Keratocyte Density After Microkeratome LASIK vs.
Femtosecond Laser-Assisted LASIK
Presenting Author: Laura de Benito-Llopis MD
Coauthors: Pilar Cañadas DO, Miguel A Teus MD, Jose L
Hernandez-Verdejo DO
Purpose: To compare the keratocyte density after microkeratome
LASIK (MK-LASIK) and femtosecond-laser-assisted LASIK (FSLASIK). Methods: We performed a prospective study of myopic
patients who underwent MK-LASIK or FS-LASIK. We measured
keratocyte density 3 and 15 months and 3-5 years after the surgery using confocal microscopy. Results: We included 31 eyes in
LASIK (FS-LASIK) and 30 eyes in MK-LASIK. We detected an
initial increase in the keratocyte population of the whole cornea,
due to an increase in the stromal bed and mid and posterior
stromal layers, followed by a normalization of those deeper
layers, and a decrease of the cell density in the stromal flap and
stromal bed 15 months postoperatively. The average cell density
throughout the cornea was not decreased compared to controls.
Conclusion: We found a reorganization of keratocytes in the cornea up to 5 years after LASIK, with a decrease in the stromal flap
and bed, but maintaining normal average cell densities, and without significant differences between MK-LASIK and FS-LASIK.
The Impact of LASIK on Tear Film Osmolarity
Presenting Author: Robert A Eden MD
Coauthors: Robert L Schultze MD, Michael Cortese OD
Purpose: To determine the effect of LASIK on tear film osmolarity. Methods: We evaluated 50 eyes with preoperative myopia
between -1.00 D and -5.00 D that underwent LASIK surgery.
Tear film osmolarity was measured using the TearLab system
pre- and postoperatively at Days 30 and 90. Results: Mean tear
osmolarity for the preoperative group was 299.97 mOsms/L,
while postoperative readings were 299.27 and 296.20 mOsms/L
at 30 and 90 days postop, respectively. Analysis of variance and
Tukey test (alpha = 0.05) demonstrated no statistically significant difference between pre- and postoperative groups. Conclusion: Results suggest that tear film osmolarity does not change
significantly as a result of LASIK.
Rotationally Asymmetric Multifocal IOL: Optical
Plate vs. C-Loop Design With and Without Capsular
Tension Ring
Presenting Author: Amr M El Aswad MD
Jaime Javaloy PhD, Maria Jose Ayala MD, Alfreso Vega-Estrada
MD
Purpose: Visual performance with 2 different designs (optical
plate design vs. C-Loop design with and without capsular tension
ring (CTR) implantation of the rotational asymmetric multifocal IOL. Methods: 135 eyes were divided in 3 groups: Group A,
43 eyes implanted with the Lentis Mplus LS-312 without CTR;
Group B, 47 eyes implanted with the Lentis Mplus LS-312 in
combination with CTR; Group C, 45 eyes implanted with the
Lentis Mplus LS-313 without CTR. Results: Postoperatively, no
statistically significant differences in the uncorrected near visual
acuity (UNVA), corrected distance near visual acuity (CDNVA)
were found between groups (P = .09). A trend toward better contrast sensitivity outcome was observed in Group B in photopic
contrast sensitivity for the highest spatial frequencies (12 cycles/
degree [cpd], P = .06; 18 cpd, P = .05). In the defocus curve, significantly better visual acuities were present in eyes from Group
B for intermediate vision levels of defocus (P = .02). Significantly
higher amounts of postoperative intraocular total and high-order
aberrations were found in Group A (P = .02). Conclusions: The
Lentis Mplus is able to restore visual function after cataract
surgery. The Lentis Mplus LS-312 with CTR provides better
contrast sensitivity as well as intermediate vision, and the Lentis
Mplus LS-313 provides optical quality.
Combining Corneal Tomography and Biomechanical
Parameters for Detection of Very Mild Ectasia
Presenting Author: Fernando Faria Correia MD
Coauthors: Isaac Ramos MD, Bernardo Lopes MD, Rosane
Correa MD, Allan Luz MD, Renato Ambrosio Jr MD
E-poster #:RP 101686
Purpose: To combine tomographic and biomechanical parameters provided by Scheimpflug imaging for the diagnosis of
ectasia. Methods: One eye randomly selected from 119 patients
with normal corneas (Group N); 1 eye randomly selected from
59 patients with keratoconus (Group KC); and 19 eyes with normal topography from cases with diagnosis of keratoconus in the
contralateral eye (Group FFKC - forme fruste keratoconus) were
analyzed by Pentacam HR and Corvis ST (Oculus; Wetzlar, Germany). Topometric (front surface curvature), tomographic (front
and back elevation; comprehensive thickness), and biomechanical (deformation response) indices were analyzed. Fisher’s linear
discriminant analysis (LDA) was used for providing linear combinations of parameters that best separate normal from ectatic
corneas. The areas under the receiving operator characteristic
curves (AUC) were calculated and compared (pairwise comparisons with DeLong’s method). Results: The best LDA function
of tomographic and biomechanical parameters had AUC of 1.0
for N x FFKC (sensitivity = 100%; specificity = 99.2%) and 1.0
for N x KC (sensitivity = 100%; specificity = 100%). Pairwise
comparisons demonstrated that this parameter had better AUC
for N x FFKC than all individual tomographic and biomechanical indices (P < .05), with exception of BAD-D (P = .402; AUC
= 0.983, sensitivity = 94.7%; specificity = 96.6%). Conclusion:
Combination of corneal tomography and biomechanical data
significantly improves the ability for detecting ectasia, which has
a higher impact and relevance for detecting very mild cases.
Comparison of IOL Calculation Methods and
Intraoperative Wavefront in Eyes That Have
Undergone Refractive Surgery
Presenting Author: Ana P Fraga Santini Canto MD
Coauthors: Priyanka Chhadva BS, Anat Galor MD, Sonia Yoo
MD, Pravin K Vaddavalli MD, Florence Cabot MD, William W
Culbertson MD
Purpose: To compare methods of determining IOL power for
cataract surgery in eyes with a history of refractive surgery.
Methods: Retrospective study. Forty-six eyes of 33 patients
who had previous refractive surgery and underwent subsequent
cataract surgery. Suggested IOL power predicted by the ORange
wavefront aberrometer (WaveTec Vision Systems, Inc.), IOLMaster (Carl Zeiss Meditec; Dublin, Calif., USA), using average topographical central keratometry values (Avg K), and the
ASCRS website were compared. IOL power required for emmetropia was determined using stable post-cataract surgery manifest refraction and implanted IOL power. Results: Mean patient
age was 59 years. Fifteen percent of eyes had a history of myopic
PRK, 57% of myopic LASIK, 13% of hyperopic LASIK, and
22% of radial keratectomy (RK). In 37% of cases, the ORange
predicted IOL power within 0.50 D of emmetropia, compared
to 30% for IOLMaster, 26% for AvgK, and 17% for the
ASCRS website. In eyes with a history of myopic PRK or LASIK,
IOLMaster, ORange, and AvgK all trended toward hyperopia (range: 30%-61%). In post-RK eyes, ORange, AvgK, and
ASCRS website predicted within 0.50 D of emmetropia in 14%,
and the IOL Master in 43% of cases. Conclusion: Both overall
and in eyes status-post myopic LASIK and PRK treatments, the
ORange results most frequently predicted emmetropia. None of
the methods did well in predicting emmetropia in post-RK eyes.
Preoperative and Postoperative Size and Movements
of the Lens Capsular Bag: Ultrasound Biomicroscopy
Analysis
Presenting Author: Sonu Goel DNB MNAMS
Coauthors: Sonai Mukherjee MBBS, Nabita Barua DO
Purpose: To evaluate capsular bag size and accommodative
movement before and after cataract surgery using ultrasound
biomicroscopy (UBM) and anterior segment OCT (AS-OCT).
Methods: Eyes having cataract surgery and monofocal IOL
implantation were studied using UBM. The following parameters
were measured preoperatively and 1, 2, and 12 months postoperatively: anterior chamber depth (ACD) (also by AS-OCT), capsular bag thickness, capsular bag diameter, ciliary ring diameter,
sulcus-to-sulcus (STS) diameter, ciliary process-capsular bag
distance, ciliary apex-capsular bag plane, and IOL tilting. The
preoperative and postoperative capsular bag volumes were calculated at 12 months. The results were compared with the changes
during accommodation. Results: The study comprised 33 eyes.
With the exception of the ciliary apex-capsular bag plane, which
appeared to be unmodified postoperatively, all measured parameters showed significant variation after IOL implantation. Only
the ACD did not change significantly during accommodation.
Conclusions: After cataract surgery, the capsular bag stretched
horizontally and with reduced vertical diameter as a result of
adaptation to the implanted IOL. The capsular bag-IOL complex
filled all available space, compressing the zonular fibers and
E-Poster Abstracts
175
almost abolishing the space between the ciliary apex and the capsular bag. There was anterior chamber deepening and a decrease
in the ciliary ring diameter and STS diameter. In the absence of
zonular fiber tension, the shape of the ciliary processes may be
modified.
Explore the Computer-Animated Model of
Accommodation and Demystify Your Understanding
of Accommodation
Presenting Author: Daniel B Goldberg MD
Purpose: To demonstrate the mechanisms of accommodation
using a computer-animated model of the structures of accommodation based on new understanding of the anatomy of the zonule integrated with current understanding of the mechanism of
accommodation. Methods: The 3-D computer-animated model
was produced in collaboration with an experienced medical animator utilizing Autodesk 3-D studio MAX, Adobe Photoshop,
and Adobe AfterEffects. An ultrasound biomicroscopy (UBM)
video of human accommodation was used to help build the
model, and new knowledge of accommodation science and the
anatomy of the vitreous zonule was integrated into the model.
Results: Utilizing “model-based reasoning,” the computeranimated model enables a new perspective and framework to
demonstrate and interpret the mechanism of accommodation.
This model incorporates extensive changes in our understanding
of the vitreous zonule and attachments to the posterior lens capsule at the Weiger ligament and the anterior hyaloid membrane.
The anterior hyaloid is more anatomically detailed than previously recognized. It is the support and movement of the anterior
hyaloid that results in the shape changes of the posterior capsule
during accommodation. This changes our understanding of
“vitreous support” as previously proposed. Conclusion: There is
a reciprocal action of the anterior zonules and the posterior zonules. During ciliary body contraction, the anterior zonules lose
tension while the posterior zonules stretch and exert force on the
posterior lens capsule, playing a role in shaping the posterior lens
thickness and curvature. During ciliary body relaxation, the posterior zonules lose tension as the lens flattens and is pulled back
by the increasing tension of the anterior zonules.
176
E-Poster Abstracts
Combined Small-Incision Lenticule Extraction
(SMILE) and Corneal Crosslinking in Keratoconus:
Preliminary Report
Presenting Author: Enrique O Graue Hernandez MD
Coauthors: Gabriela Pagano MD, Tito Ramírez-Luguín MD,
Alejandro Navas MD, Arturo J Ramirez-Miranda MD
E-poster #:RP101592
Purpose: To report the preliminary data on safety, stability, and
efficacy of this combined treatment. Methods: Inclusion criteria:
topographic diagnosis of keratoconus, corrected spectacle distance visual acuity (> 20/40) and residual total corneal thickness
after lenticule extraction > 400 microns. Patients were treated
with femtosecond small-incision lenticule extraction (SMILE,
Visumax 500 KHz, Carl Zeiss Meditec; Germany) immediately
followed with intrastromal collagen crosslinking (0.1% isotonic
riboflavin [Medio-cross; Colombia]) placed inside the pocket
for at least 10 minutes and irriadiated with UVA 7 mW/cm2
for 30 minutes (IROC; Switzerland). Follow-up was done at 1
day, 1 week, and 1, 3, and 6 months. Uncorrected distance VA
(UDVA), corrected distance VA (CDVA), subjective refraction,
corneal tomography (Vistante OMNI, Carl Zeiss; Germany)
and complete ophthalmic exam were recorded at each visit.
Results: Six eyes were treated. Mean follow-up was 7 weeks
(range: 1-9). Preop logMAR UDVA was 1.35 (range: 1.06-1.3),
postop logMAR was 0.27 (range: 0.56 to -0.12), preop logMAR
CDVA was 0.0 (range: -0.04 to 0.02 ), and postop logMAR
CDVA was 09 (range: 0.3 to -0.02). This difference was not
statistically signficant (P > .5). Mean preoperative spherical
equivalent was -4.93 D (range: -3.75 to -6.75). Preoperative and
postoperative differences in UDVA were statistically significant
(P < .05). No eyes lost more than 2 lines of CDVA. All patients
had transient intrastromal haze that resolved during the first 2-3
weeks. Conclusions: Sequential SMILE and intrastromal collagen
crosslinking appears to be a safe, effective, and stable refractive
procedure in the short term. Larger sample and longer follow-up
are required.
Potential Application of LipiFlow Thermal Pulsation
System for Preoperative Treatment of Dry Eye Signs
and Symptoms
Presenting Author: Jack Volker Greiner DO
Purpose: To explore the potential short- and long-term benefits
of LipiFlow Thermal Pulsation treatment in dry eye patients
with meibomian gland dysfunction (MGD) that may otherwise
not qualify for anterior segment surgical procedures. Methods:
Patients diagnosed with MGD and moderate to severe dry eye
that would preclude their qualification for anterior segment
surgery were recruited for a nonsignificant risk, prospective,
open-label clinical trial. Meibomian gland assessment (MGA)
and standard patient evaluation of eye dryness (SPEED) scores
in subjects (n = 12, 24 eyes) were determined at baseline, 1
month, and 2 and 3 years after treatment with a single 12-minute
LipiFlow Thermal Pulsation System (LTPS) procedure. Results:
MGA at baseline was 5.1 ± 4.0 vs. 1 month 11.5 ± 5.9 (P .05).
Significance was determined by repeated measures ANOVA with
post-hoc Bonferroni corrected post-hoc testing. Conclusion: A
single 12-minute LTPS treatment results in short-term (1 month)
and long-term (2-3 years) improvement in meibomian gland
function and dry eye symptoms. Thus this procedure may have
considerable potential as a preoperative treatment for MGD and
dry eye in patients who otherwise may be excluded from procedures such as refractive surgery or corneal transplantation. Furthermore, the remarkably long improvement in meibomian gland
function suggests that the benefits of a single LPTS may extend
well beyond the immediate postoperative period.
Ocular Higher-Order Aberration Changes After
Implantable Collamer Lens Implantation for High
Myopic Astigmatism
Presenting Author: Seyed Javad Hashemian MD
Purpose: To investigate the changes in higher-order aberrations (HOAs) induced by implantation of Implantable Collamer
Lenses (ICL and Toric ICL, Staar Surgical; Nidau, Switzerland)
in eyes with high myopia and high myopic astigmatism. Design:
Prospective, observational case series. Methods: We investigated
33 eyes of 18 consecutive patients, with spherical equivalent
errors of -6.00 to -21.09 D and cylindrical errors of -0.5 to -4.75
D, who underwent ICL and toric ICL implantation. Before and 5
days, 2 and 6 months after surgery, the UCVA, BSCVA, defocus,
and adverse events of the surgery were assessed. Ocular HOAs
also were evaluated by Hartmann-Shack aberrometry (Technolas PV; Rochester, New York, USA) before and 6 months after
surgery. Results: The UCVA and BCVA were 20/20 in 40% and
66.7% of eyes 6.0 months after surgery, respectively. Mean defocus refraction and astigmatism were reduced to -0.66 and 0.65
D 6.0 months postoperatively, from -12.79 and 2.18 at baseline,
respectively. For a 6-mm pupil, HOAs were not significantly
changed, merely from 0.417 ± 0.162 µ before surgery to 0.393 ±
0.119 µ after surgery (P = .45). No vision-threatening complications occurred during the observation period. Conclusions: In
the author’s experience, the ICL and toric ICL performed well in
correcting high myopic astigmatism without significant changes
in HOAs during a 6.0-month observation period, suggesting its
viability as a surgical option for the treatment of such eyes.
E-Poster Abstracts
177
Comparing and Evaluating the Anterior Chamber
Depth by Ultrasound Biomicroscopy, Orbscan II, and
Lenstar in High Myopic and Keratoconic Eyes
with an investigational APIOL demonstrated good visual acuity,
with stable and predictable refractive result.
Presenting Author: Seyed Javad Hashemian MD
Clinical Performance and Patient Satisfaction After
Implantation of New Multifocal IOL: Soleko Fil 611pv
Purpose: To compare and determine the accuracy measurements
of anterior chamber depth (ACD) in high myopic and keratoconic subjects by ultrasound biomicroscopy (UBM), Lenstar, and
scanning-slit topography (Orbscan II). Methods: The ACD was
measured by 3 methods—UBM, Lenstar, and Orbscan II—in 94
eyes of 48 high myopic patients and 46 eyes of 26 keratoconic
subjects. Repeatability, reproducibility, and intraclass correlation coefficients (ICC) of ACD measurements in UBM were
evaluated. Results: The mean ACD was 3.18 ± 0.27, 3.20 ± 0.27
and 3.14 ± 0.28 mm with UBM, Lenstar, and Orbscan II in the
high myopic group, respectively. The mean ACD was 3.12 ±
0.22, 3.13 ± 0.23, and 3.07 ± 0.23 mm with UBM, Lenstar, and
Orbscan II in the keratoconic group, respectively. The coefficient
of repeatability and reproducibility of ACD measurements with
UBM were < 5%. The ICCs were 0.95 with Lenstar and Orbscan
II in the high myopic group and 0.96 with Lenstar and 0.94 with
Orbscan II in the keratoconic group, respectively. Conclusions:
The ACD measurements were comparable among UBM, Lenstar, and Orbscan II. There was no significant difference in ACD
measurements among these 3 devices.
Four-Year Outcomes With an Investigational
Anterior Phakic IOL: Multicenter Canadian Clinical
Trial
Presenting Author: Simon P Holland MD
Coauthors: Thadeus Demong MD, Theodore Rabinovitch MD,
Michel Pop MD, Francis Roy MD
Purpose: To evaluate clinical outcomes 4 years after implantation of an anterior phakic intraocular lens (APIOL) bilaterally
for moderate to high myopia. Methods: In a prospective, multicenter, 5-year study conducted in Canada, 225 subjects (18 to 49
years old) with preoperative mean spherical equivalent (SE) of
-10.56 D at a range of -6.25 D to -16.88 D underwent implantation of an investigational APIOL. Study criteria excluded previous corneal or intraocular surgery, history of glaucoma, 2.0 D.
Assessments at the 4-year follow-up visit included SE, predictability of refraction, bilateral UCVA and BCVA, central and
peripheral endothelial cell density (ECD) analysis, and central
and peripheral ECD chronic change. Results: Mean SE was -0.32
D (n = 215) at 3 years and -0.35 D (n = 167) at 4 years postoperatively. Predictability of refraction within ±1.00 D was 96.7% (n
= 215) at 3 years and 94% (n = 157) at 4 years. Mean logMAR
bilateral UCVA was -0.01 ± 0.17 at 4 years (n = 167). Mean
logMAR bilateral BCVA was -0.13 ± 0.11 at 4 years (n = 167).
Mean central ECD and SD was 2836.0 ± 335.9 (n = 207) at 6
months, 2730.6 ± 321.4 (n = 215) at 3 years, and 2732.4 ± 337.6
(n = 156) at 4 years. Mean chronic annualized change in central
ECD at 4 years (6 months to 4 years) was -1.2% ± 2.4 (n = 146).
Mean peripheral ECD and SD was 2947.7 ± 339.2 (n = 204) at 6
months, 2800.3 ± 352.7 (n = 213) at 3 years, and 2796.5 ± 349.6
(n = 155) at 4 years. Mean chronic annualized percentage change
in peripheral ECD at 4 years (6 months to 4 years) was -1.6%
± 2.2 (n = 142). Conclusions: Four-year bilateral clinical result
Presenting Author: Claudio Iacobucci MD
Coauthors: Daniele DiClemente MD, Emiliana DiNardo OD,
Bernardo Billi MD
Purpose: To determine the results and the visual performance
following an implantation of a new multifocal refractive IOL
for cataract surgery, able to avoid postoperative visual problems
common with other traditional IOLs. Methods: 462 eyes were
enrolled in this retrospective study. Seventy-six patients were
implanted with bilateral new premium IOL, the Soleko Fil 611
pv, and analyzed for UCVA and BCVA for distance (fd), near
(fn), and intermediate vision. Vision was measured using ETDRS
charts, including high/low contrast visual acuity and glare/optical
aberrations. Results: Preliminary results at 1 year following surgery are presented. The patients were divided into 3 groups, A, B,
and C. Group A: 180 eyes; average age 69.63, SD ± 9.928; monocular UCVA fd 20/20: 75%. Group B: 224 eyes; average age
73.65, SD ± 8.219; mon. UCVA fd 20/25: 72.76%. Group C:
58 eyes; average age 78.25, SD ± 8.548; mon. UCVA fd 20/40:
70.68%. Group A: UCVA fn: J368, 33%. Group B: UCVA fn:
68.75%. Group C: UCVA fn: J4 62.06. Only 0.86% of eyes had
moderate glare optical aberrations. In a further 0.86% of eyes
there was a complication resulting from incorrect lens power
that required IOL explantation. 67.74% of A, B, and C groups,
altogether considered, never use presbyopic spectacles. Conclusions: Excellent results were obtained with Soleko Fil 611 pv, but
in all cases, this new IOL provided good results for distance and
significatively near vision without problems of traditional multifocal IOLs.
178
E-Poster Abstracts
High Myopia Outcomes With Latest-Generation
Excimer Laser
Presenting Author: Ananda Kalevar MD
Coauthors: Mounir Bashour MD, Eser Adiguzel PhD, Mark
Cohen MD, Avi Wallerstein MD
Purpose: To determine the accuracy, efficacy, safety, and stability of laser vision correction (LVC) in high myopia greater than
-10 D with a newer generation excimer laser. Methods: Prospective cohort study of contact lens-intolerant myopes with greater
than -10 D manifest refractive spherical equivalent (MRSE). All
eyes underwent aspheric PRK or LASIK targeting emmetropia,
with a 400-Hz excimer laser. All performed by a single surgeon.
Postop MRSE, cylinder, UDVA and CDVA were compared to
preop measurements. RM-ANOVA and Holms Sidak post hoc
tests were used. A subjective quality of vision questionnaire was
administered. Thirty-eight eyes (22 patients) were included in
the study, with preop average MRSE of -11.35 ± 1.08 D (range:
-10.13 to -14.63 D); 26 eyes had postop data of 6 months or
greater. Mean follow-up time was 12.5 ± 5.0 months. Results:
Cumulative UDVA of 20/20, 20/25, and 20/40 or better in 46%,
65%, and 92% of eyes, respectively, compared to preop cumulative CDVA of 63%, 87%, and 100%, respectively. Thirty-nine
percent, 50%, and 85% of eyes were within ±0.25, ±0.50, and
±1.00 D of emmetropia (R2 = 0.679). The only visual acuity
loss was 1 Snellen line loss of CDVA in 1 eye (20/20 to 20/25).
Postop MRSE was stable, with no significant differences between
MRSE at 1, 3, 6 months, or later timepoints. 100% of patients
were satisfied with their results at 6 months or more after surgery, with 31% very satisfied. The cohort of eyes with greater
than -10 D MRSE of myopia had better accuracy, efficacy,
safety, stability, and satisfaction profiles than those published in
high myopia with previous excimer laser technology. The safety
profile was equivalent to that in low to moderate myopia, with
excellent subjective satisfaction. Conclusion: Candidacy criteria
for LVC should include contact lens intolerant high myopes
between -10 to -14D.
Corneal Crosslinking and Long-term Hyperopic
LASIK Stability: Initial Clinical Findings in a
Contralateral Eye Study
Presenting Author: A J Kanellopoulos MD
Coauthors: Gregory Pamel MD, George Asimellis MD
E-poster #: RP 101515
Purpose: To evaluate the safety and efficacy of the application
of intrastromal corneal crosslinking (CXL) in a contralateral
eye study in routine hyperopic LASIK. Methods: Twentyseven consecutive hyperopic and hyperopic astigmatic bilateral
topography-guided LASIK patients were randomized to receive
5 minutes of 10 mW/cm2 CXL after in-the-flap administration
of a single drop of 0.1% sodium phosphate riboflavin solution.
All cases were treated with the Allegretto 400Hxz Eye-Q excimer
laser and femtosecond laser flap creation. Preoperative refractive
error, keratometric, topographic, and topometric measurements
were evaluated, with a mean follow-up of 23 months (22-35).
Results: Mean sphere was +3.25 D; Cyl: -1.75 D. The CXL cases
demonstrated a mean regression from treatment of +0.22 D;
the non-CXL cases: + 0.72 D—showing a very strong statistically significant difference even in the first 6 months, despite the
expected flattening effect of CXL. Conclusions: These prelimi-
nary data suggest that the combination of CXL in hyperopic
LASIK may offer a very significant synergy in efficacy, suggesting that in hyperopic LASIK long term regression may be more
related to an intrinsic biomechanical effect.
Can Overall Corneal Epithelial Thickness Become a
Very Early Ectasia Prognostic Factor?
Presenting Author: A J Kanellopoulos MD
Coauthors: Ioannis M Aslanides MD PhD, George Asimellis
PhD, Gregory Pamel MD
Purpose: To assess the safety and efficacy of overall corneal
epithelial thickness (OET) measurement as an early ectasia (EE)
prognosis tool. Methods: OET was taken with high-frequency
ultrasound biomicroscopy (HF-UBM), and normal (N), keratoconic (K), and K eyes treated with collagen crosslinking (KCXL)
were compared and a statistical study was conducted. Results:
Epithelial thickness varied substantially in the K group; however,
there was an overall thickening of the epithelium, particularly
over the pupil center on the order of +3 µm, while the mean
epithelial thickness on average was +1.1 µm in the N and KCXL
groups (P < .0005). Conclusion: HF-UBM indicates that on average, epithelium in the K group was thicker, possibly as a reaction
to ectasia. This may aid in the subclinical screening of eyes.
Evaluation of Corneal Power Changes After Myopic
Laser Refractive Surgery With A New Scheimpflug
Camera Device
Presenting Author: Michele Lanza MD
Coauthors: Michela Cennamo MD, Carlo Irregolare MD,
Filippo Ranni MD, Giovanni Coen MD
Purpose: To study the accuracy of Sirius tomography (CSO,
Inc.; Italy) in evaluating corneal power changes after myopic
phororefractive keratecotomy (PRK). Methods: 113 eyes of 68
patients underwent myopic PRK, with a refractive error measured as spherical equivalent ranging from -0.50 D to -10.25 D
(mean: -5.01 ± 2.48 D). A complete ophthalmic evaluation and a
Sirius scan were performed before surgery and at 3 and 6 months
follow-up, anterior corneal Sim’Ks at 3 mm and 5 mm have
been included in this study. Statistical analysis was run to check
the correlations between the changes in the subjective refraction
and the changes in keratometry with Pearson test and the differences between preoperative and postoperative data with Student
paired t test. Results: Three months after PRK, Sirius Sim’K at 3
mm and at 5 mm showed a very good correlation (R2 = 0.875
and R2 = 0.912, respectively) but a significant difference (P <
.001) with effective treatment (mean = -3.32 ± 1.93 D and -0.56
± 1.93 D, respectively). Six months after PRK, Sirius Sim’K at 3
mm and at 5 mm showed very good correlation (R2 = 0.892 and
R2 = 0.936, respectively) but a significant difference (P < .001)
with effective treatment (mean= -3.2 ± 1.77 D and -0.59 ± 1.17
D, respectively). Conclusions: According to our results, Sirius
tomography is not able to precisely provide corneal power value
after myopic refractive surgery.
E-Poster Abstracts
Evaluation of Speed and Amplitude of Corneal
Deformation in Naïve Eyes Utilizing Oculus Corvis
Presenting Author: Michele Lanza MD
179
Topography-Guided Photorefractive Keratectomy
Using Allegretto Laser With Simultaneous
Crosslinking for Keratoconus
Coauthors: Mich Cennamo MD, Gianluca Scarfato MD, Carrlo
Irregolare MD, Maddalena De Bernardo MD
Presenting Author: David Lin MD
Purpose: To evaluate efficacy and safety of simultaneous topography-guided photorefractive keratectomy (TG-PRK) with collagen crosslinking (CXL) for keratoconus (KC). Methods: 193
eyes with contact lens-intolerant KC underwent TG-PRK with
Allegretto Wavelight (AW) laser using a custom Topography
Neutralization Technique (TNT) with simultaneous CXL, performed according to the Dresden protocol. Degree of refractive
correction was based on residual stromal depth of 300 microns
with target correction of -1.0 D. UCVA, BCVA, keratometry
(K), efficacy, and safety were evaluated at 12 months. Results:
Fifty-eight eyes completed 12 months follow-up. Thirty-four of
95 eyes (59%) had UCVA of 20/40 or better. Thirty-three of 58
(57?) had BCVA improved, 16/58 (28?) had no change, 6/58
(10%) lost 2 lines of BCVA. Mean astigmatism decreased from
-2.76 D preoperatively to -1.39 D postoperatively. Mean postoperative refractive spherical equivalent (SE) regressed from -0.74
at 3 months to -1.01 at 12 months, with 11/58 (19%) having
hyperopic progression. One eye had SE of > 1 D. Complications
included one herpetic keratitis with four with delayed epithelial
healing. Conclusions: Simultaneous topographically guided PRK
with CXL offers promising early results and good efficacy and
safety for contact lens-intolerant KC using the AW laser. At 1
year follow-up, more than half of the eyes achieved UCVA of
20/40 or better, with improved BCVA in 28% and a minimal
complication rate.
Purpose: To study corneal biomechanical properties in healthy
subject eyes performed with Oculus Corvis and their correlation
with corneal morphological parameters. Methods: Sixty-nine
eyes of 69 healthy subjects underwent a complete ophthalmic
evaluation, Oculus Corvis (OC) analysis, and Scheimpflug
Camera (SC) scan. SPSS software has been used to check correlations among OC parameters as applanation time (AT), length
(AL), and velocity (AV); highest concavity velocity (HCV), time
(HCT), and deformation amplitude (HCDA); central corneal
thickness (CCT), and anterior corneal power (ACP) measured
with SC. Results: CCT showed a low correlation with AT (R2 =
0.33) and HCDA (R2 = 0.2) and a poor correlation with AL
(R2 = 0.0003), AV (R2 = 0.04), HCV (R2 = 0.067), HCT (R2 =
0.082). ACP showed a low correlation with AT (R2 = 0.35),
HCV (R2 = 0.23), and HCDA (R2 = 0.24) and a poor correlation with AL (R2 = 0.0022), AV (R2 = 0.12), and HCT (R2 =
0.023). Conclusions: According to our data, OC seems to provide an evaluation of corneal biomechanical properties independent of corneal morphological parameters and could be helpful
in clinical practice.
New Use of Smartphones to Aid Patients With
Postoperative Treatment Regimes and Long-term
Care
Presenting Author: Nicola M Lau MBBS
Coauthor: Julian D Stevens FRCS
Purpose: To demonstrate the effectiveness of a unique, innovative, and multifunctional mobile phone application developed
to improve eye medication compliance, patient education, and
quality of care. Methods: An innovative mobile phone software
application, CleverDrops, has been developed for smartphones,
tablet computers, and other mobile devices. This multipurpose,
user-friendly software is programmed to improve quality of care:
a built-in reminder for eye-drops set according to the surgeon’s
specified regime and tailored to the patient links to patient
educational videos and health information, available at the fingertips along with appointment reminders and alerts. A patient
satisfaction survey was carried out on patients who underwent
laser refractive eye surgery in a single-surgeon practice. Results:
The application software has reduced patient queries and helped
to improve drops compliance, medical education, and continuity of care. The app is able to track compliance with medication
regimes and so is very useful post-surgery and for glaucoma
and ocular oncology. Conclusion: The innovative mobile phone
software application CleverDrops is an effective, simple-to-use
tool in improving quality of care for patients undergoing refractive and cataract surgery and compliance in long-term treatment
regimens.
Coauthor: Simon Holland MD
180
E-Poster Abstracts
Noninvasive Vision Correction: Refractive Index
Changes in Cornea, Lens, and Hydrogels With a
High Rep Rate Femto Laser
Presenting Author: Scott M MacRae MD
Coauthors: Lisen Xu PhD, Daniel Salvage MS, Krystel Huxlin
PhD, Wayne H Knox PhD
Purpose: To investigate a new approach for correcting refractive
error by creating large refractive index (RI) changes in living corneas and hydrogel (IOL) materials. Methods: We contrasted the
magnitude of RI changes induced by 400-nm and 800-nm laser
pulses, 100 fs in duration and 80 MHz repetition rate, scanned
at 0.1 to 400 mm/s in living cat corneas, lens slices, and hydrogel
materials. Lines of RI change that were created were imaged
using differential interference contrast microscopy and OCT. In
living corneas, we assessed the corneas’ biological reaction to the
RI change by immunochemistry. Results: 400-nm femtosecond
laser pulses were the most effective at inducing RI change. In living cat corneas, RI increased by up to 0.04+0.004. In hydrogels,
RI could be increased by 0.05+ 0.005. Such RI change is sufficient to alter sphere or cylinder by 1-3 D. Tunnel assay revealed
lack of epithelial, stroma, and endothelial changes around the
lines of RI change. There was no increase in alpha smooth muscle actin, or fibronectin expression around the fs lines, which persisted for at least 12 weeks, suggesting no corneal wound healing
response post-lasering. OCT showed no significant changes in
thickness or curvature of the materials. Conclusion: We can alter
the refractive state of ocular tissues and IOL hydrogels by causing localized changes in refractive index with an ultrafast femtosecond laser treatment that does not induce significant damage
or alteration in shape.
Early Refraction and Visual Recovery Enhancement
in Post Myopic PRK Eyes Using Myopic Soft Contact
Lenses
Presenting Author: Scott M MacRae MD
Coauthors: Ryan Vida OD, Len Zheleznyak MS
Purpose: To analyze early refraction data in post-PRK eyes to
optimize visual recovery in post-myopic PRK eyes using myopic
soft contact lenses. Methods: We performed a randomized contralateral eye study (38 eyes) placing either a -1.25 myopic bandage soft contact lenses (SCL) and then a plano SCL in the contralateral eye of in bilateral PRK-treated patients. We compared
the preoperative and early postoperative refractions and visual
acuities at 1,7, and 14 days and 1 and 3 months postoperatively.
At the 1-week exam, visual acuity and manifest refractions were
performed prior to SCL removal, which was done at 1 week
postop. Results: Preoperatively, the mean refractive spherical
equivalent (SE), -4.7 D +- 2.1 for both groups and BCVA (both
groups 20/19) preoperatively were well matched. At 1 day and 1,
2, and 4 weeks postop, the mean SE was 0.0*, -0.3*, -0.5, -0.1 D
in the -1.25 myopic SCL vs. -1.1*, -1.0*, -0.5, and 0.2 D in the
plano SCL and eyes, respectively. Postop visual acuity was significantly better at 1 day 20/38 vs. 20/45* and 1 week 20/31 vs.
20/44* postoperatively in the -1.25 myopic SCL eyes compared
to the plano SCL eyes (*P < .05). The early postoperative myopia showed no significant correlation with level of preoperative
myopia (R2 < 0.10). Conclusions: Postop myopic PRK eyes were
typically slightly myopic at the 1 day and 1 week postop visit,
which may cause delayed visual recovery and reduced vision. We
noted that refraction and treatment with a myopic SCL speeds
distance vision recovery in the first 2 weeks.
Corneal Collagen Crosslinking in Patients With
Previous Unilateral or Bilateral Radial Keratotomy
Presenting Author: Parag A Majmudar MD
Coauthors: Roy S Rubinfeld MD, William B Trattler MD,
Marwa Adi MD, Aaleya Koresishi MD, Gabriela Perez MD
Purpose: To evaluate the safety and efficacy of epithelial-on corneal collagen crosslinking (CXL) in patients with preoperative
radial keratotomy (RK). Methods: Patients with either unilateral
or bilateral RK prior to receiving CXL were evaluated. Outcome
measures included UCVA and BSCVA and astigmatism at 3 and
6 months post-CXL treatment. Results: Four eyes of 4 patients
with previous unilateral RK and 8 eyes of 4 patients with previous bilateral RK met inclusion criteria and were evaluated. Fifty
percent of unilateral eyes were male, while 75% of bilateral
eyes were male. The average age of unilateral and bilateral eyes
was 57 and 55 years old, respectively. In patients with previous
unilateral RK, 33% of patients had a preop UCVA of 20/60 or
better; 33% of these patients had a UCVA of 20/60 or better at
3 months, and 67% of these patients had a UCVA of 20/60 or
better at 6 months. In patients with previous bilateral RK, 38%
of patients had a preop UCVA of 20/60 or better; 75% of these
patients had a UCVA of 20/60 or better at 3 months and at 6
months. In patients with previous unilateral RK, 50% of patients
had a BSCVA of 20/25 or better at preop, and 100% of patients
had a BSCVA of 20/25 or better at 6 months. In patients with
previous bilateral RK, 38% of patients had a BSCVA of 20/25
or better at preop and 75% of patients had a BSCVA of 20/25
or better at 6 months. Both groups of patients experienced an
overall average improvement (decrease) in manifest astigmatism.
Conclusion: Epi-on CXL appears to be safe and effective for eyes
with preop RK unilaterally or bilaterally.
Reliability of Central Pachymetry After Advanced
Surface Ablation Using Scanning-Slit Topography
and Specular Microscopy
Presenting Author: Miguel J Maldonado PhD
E-Poster Abstracts
ability of PCI for gauging AL is much poorer especially in eyes
above 27 mm. This measurement random error can produce IOL
power miscalculations resulting in spherical ametropia higher
than 0.75 D.
Coauthors: Alberto López-Miguel PhD, Loreto MartinezAlméida MS, Maria E Mateo BS, Maria B Coco-Martin PhD,
Maria E Correa-Pérez MD
Femtosecond Laser-Assisted LASIK to Correct
Medium to High Hyperopic Defects
Purpose: To assess the repeatability and the intersession and
interobserver reproducibility and agreement of central corneal thickness (CCT) measurements obtained by scanningslit topography (SST) and noncontact specular microscopy
(NCSM) after advanced surface ablation (ASA). Methods: To
analyze repeatability, one examiner measured 63 postmyopic
ASA eyes 5 times successively using both techniques randomly.
To calculate interobserver reproducibility, a second examiner
obtained another CCT measurement in a random fashion. To
study intersession reproducibility, the first operator obtained
CCT measurements from another 24 eyes during 2 sessions 1
week apart. Results: Intrasession repeatability: SST and NCSM
within-subject standard deviation (Sw) and intraclass correlation
coefficient (ICC) were 7.35 µm and 3.81 µm, and 0.97 and 0.99,
respectively. Interobserver reproducibility: SST measurement
variability showed correlation with CCT magnitude (rs = -0.38;
P = .002), whereas NCSM did not. NCSM Sw and ICC were
3.83 µm and 0.99, respectively. Intersession reproducibility: No
difference in CCT measurements was found for any technique;
Sw and ICC estimates for SST and NCSM were 12.2 µm and
8.37 µm, and 0.94 and 0.95, respectively. We found a tendency
for the difference (mean SST-NCSM = 13.39 µm) to increase in
thicker corneas (rs = 0.45, P = .001). Conclusion: Both noncontact pachymetry techniques provided highly repeatable and quite
reproducible CCT measurements in post-ASA patients having no
clinically significant corneal haze, except for SST interobserver
reproducibility, which decreased in thinner corneas. However,
neither technique was interchangeable. The estimates provided
should help clinicians differentiate real CCT change from noncontact pachymetry measurement variability after ASA.
Presenting Author: Luigi Mosca MD
Implantable Collamer Lens Decreases the
Dependability of Axial Length Measurements Using
Partial Coherence Interferometry
Presenting Author: Miguel J Maldonado PhD
Coauthors: Alberto López-Miguel PhD, Maria B Coco-Martin
PhD, Loreto Martinez-Alméida MS, Maria E Correa-Pérez MD,
Juan C Nieto MS
Purpose: To evaluate axial length (AL) using partial coherence
interferometry (PCI) in myopic eyes undergoing the phakic
implantable collamer lens (ICL). Methods: AL measurements
were performed in 39 eyes prior to the surgery and 2 months
later. Twenty-five nonsurgery controls having high myopia
were also gauged following the same scheme. Paired t test and
Bland and Altman analysis was performed. Results: Mean difference between both measuring sessions was 0.03 mm (P =
.18) and 0.005 mm (P = .95) in the ICL and control groups,
respectively. However, ICL patients with AL = 27 mm showed
greater absolute differences (P = .01). Additionally, the width
of limits of agreement was 0.66 mm and 0.16 mm for ICL and
control myopes, respectively. Conclusion: After ICL surgery, reli-
181
Coauthors: Alessandra Balestrazzi MD, Luca Iacobelli MD,
Luca Mosca MD, Laura Guccione MD, Maria Ilaria Giannico
MD, Benedetto Falsini MD, Emilio Balestrazzi MD
Purpose: To evaluate efficacy and safety of femtosecond laserassisted LASIK in congenital hyperopia. Methods: 132 eyes
of 77 patients (3 groups: A, B, C) underwent femtosecond
laser-assisted LASIK. In Group A (86 eyes of 49 patients; mean
age: 40.24 years ± 9.21 SD), the surgery was performed with a
60-kHz femtosecond laser and with a Technolas 217c excimer
laser for a mean refractive error in SE of +3.34D ± 1.24 SD
(range: +0.75 / +7.25), a mean UCVA of 0.58 ± 0.21 SD and
mean BSCVA of 0.98 ± 0.06 SD; the mean laser refractive treatment in SE was of +3.02 D ± 1.24 SD. In Group B (21 eyes of 13
patients, mean age: 29.00 years ± 12.69 SD), the operation was
performed with a 150-kHz femtosecond laser and with a Visx
S4 excimer laser, for a mean refractive error in SE of +3.48 D ±
1.55 SD (range: +0.50 / +6), mean UCVA of 0.42 ± 0.20 SD
and mean BSCVA of 0.99 ± 0.04 SD; the mean refractive laser
treatment in SE was of +3.43 D ± 1.66 SD. In Group C (25 eyes
of 15 patients; mean pupil diameter: 7.97 mm ± 0.23 SD; mean
refractive error in SE of +2.58 D ± 1.42 SD), an iLASIK with a
150-kHz femtosecond laser and a wavefront customized (WaveScan) excimer laser ablation with a Visx 4S excimer laser was
performed for a mean ablation in SE of +2.71 D ± 1.48 SD, a
mean UCVA of 0.50 ± 0.23 SD and a mean BSCVA of 0.94 ±
0.14 SD. Results: One year postop, in Group A the mean UCVA
was 0.96 ± 0.07 SD and the mean BSCVA was 0.98 ± 0.05 SD;
in Group B, the mean UCVA was 0.98 ± 0.04 SD and the mean
BSCVA was 0.99 ± 0.04 SD; and in Group C, the mean postoperative UCVA was 0.94 ± 0.08 SD. Conclusions: Femtosecond
laser-assisted hyperopic LASIK is safe and effective. 150-kHz
femtolaser allows us to reduce the amount of energy employed
and the related surgical time. Customized wavefront treatments
may be useful in case of larger pupil diameter.
182
E-Poster Abstracts
Pachymetric Parameters and Belin/Ambrosio
Posterior Corneal Elevation to Diagnose Sublinical
Keratoconus
Correlation Between Pentacam HR Belin/Ambrosio
Display Score and Ocular Response Analyzer
Keratoconus Match Score Index
Presenting Author: Orkun Muftuoglu MD
Presenting Author: Edwin W Nunnery BS
Coauthors: Orhan Ayar MD, Arsen Akinci MD, Kemal Ozulken
MD
Coauthor: James B Randleman MD
Purpose: To evaluate the Belin/Ambrosio Ectasia Screen and
other parameters in patients with unilateral keratoconus in one
eye and subclinical keratoconus in the fellow eye. Methods:
Fifty-eight eyes of 28 patients with unilateral keratoconus in one
eye and subclinical keratoconus in the fellow eye were included
in the study. Each eye was evaluated by Scheimpflug rotating
camera imaging (Pentacam; Wetzlar, Germany). The Belin/
Ambrosio Ectasia Screen, posterior elevation, posterior elevation
pattern, sagittal and tangential curvature patterns pachymetry,
and corneal power were analyzed and compared. Results: Six
of 31 patients (12.9%) with subclinical keratoconus had positive Belin/Ambrosio ectasia, and 6 of 28 patients (21.4%) had
positive significant back elevation. Twenty-six patients (83.9%)
with sublicinical keratoconus had positive tanngential curvature
pattern and 21 patients (67.7%) had positive sagittal curvature
pattern. Conclusion: Tangential curvature pattern has the highest
sensitivity, whereas the Belin/Ambrosio ectasia screen has a low
sensitivity to detect subclinical keratoconus.
Relative Pachymetry and Asphericity After Myopic
Excimer Laser Refractive Surgery
Presenting Author: Orkun Muftuoglu MD
Coauthors: Arsen Akinci MD, Kemal Ozulken MD, Orhan Ayar
MD
Purpose: To evaluate the changes in relative pachymetry and
asphericity after myopic excimer laser refractive surgery. Methods: IntraLase femtosecond laser (AMO Inc.; Irvine, Calif., USA)
was used to create the flap in all eyes that underwent LASIK. All
eyes underwent LASIK with Zeiss MEL-80 excimer laser for the
correction of myopia or myopic astigmatism. Thirty-two eyes of
16 patients were included in the study. The minimum required
follow-up was 6 months after LASIK. Each eye was evaluated
by Scheimpflug camera imaging (Pentacam; Wetzlar, Germany).
Relative pachymetry and asphericity values were analyzed and
compared. Results: The mean relative pachymeter significantly
decreased from -0.8 ± 0.2 (0.1 to -0.9) µm before surgery and
-3.4 ± 1.1 µm after surgery. The mean asphericity with Q value
was significantly increased from -0.17 ± 0.11 preoperatively to
0.38 ± 0.39 postoperatively . There was a significant correlation
between the achieved correction and decrease in relative pachymeter and also between inrease in asphericity. Conclusion: The
relative pachymeter decreases and the asphericity increases after
myopic refractive excimer laser surgery.
Purpose: To evaluate the correlation between the Pentacam HR
Belin/Ambrosio Display Score (BAD), Ambrosio Relational
Thickness (ART max) and the Ocular Response Analyzer (ORA)
Keratoconus Match Score Index (KCM) in patients with suspicious Placido-based topographic patterns. Methods: Pentacam
HR and ORA were performed in consecutive patients with
suspicious Placido-based topographic patterns. The Pentacam
HR BAD and ART max and the ORA KCM were compared to
each other and correlations between tests were determined using
Pearson correlation coefficient (r) for statistical analysis. Results:
Sixty-four eyes from 32 patients were evaluated. There was good
inverse correlation between the BAD and ART scores (r = -0.73)
but poor correlation between BAD and ORA KCM (r = -0.33)
and ART max and KCM (r = 0.36). Among 14 eyes identified
as suspect by the BAD or ART max scores, 7 (50%) were also
identified as suspect by the KCM. Conversely, among 44 eyes
identified as suspect by the KCM, 7 eyes (16%) were also identified as suspect by the BAD or ART max. Conclusions: While
both values generated from the Pentacam HR showed good correlation with each other, the Pentacam HR and ORA indices did
not correlate with one another. This finding suggests that these
tests are not interchangeable and may not be reliably reproducible. The specific efficacy of one device over the other remains to
be determined.
Comparison of Epithelial-On Crosslinking for the
Treatment of Mild, Moderate, Severe, and Extremely
Steep Keratoconus
Presenting Author: Gabriela Perez BS
Coauthors: Kathryn Hatch MD, John H Talamo MD, Gregg J
Berdy MD, Ranjan P Malahotra MD, William B Trattler MD,
Eric A Liss MD
Purpose: To evaluate the efficacy of epithlial-on (epi-on) corneal
collagen crosslinking (CXL) in patients with varying grades
of ectatic corneal disease. Methods: Patients that received epion CXL were evaluated and classified into mild, moderate, or
severe keratoconus based on preop steep K values of less than
51 microns, 51 to 56 microns, 56 to 65 microns, and above 65
microns. Outcome measures included UCVA, BSCVA, astigmatism, Atlas topography measures, and Oculus Pentacam
measures. Results: 161 eyes met inclusion criteria; 57% of these
eyes were classified as mild, 20% as moderate, 18% as severe,
and 6% as extremely steep. Twenty-nine percent of severe eyes
and 44% of extremely steep eyes improved in UCVA by 1 or
more lines; 48% of mild eyes, 47% of moderate eyes, and 38%
of severe eyes improved in BSCVA by 1 or more lines. Severe and
extremely severe patients, on average, experienced a flattening
of Pentacam pachymetry apex. Mild and moderate eyes experienced an average decrease in astigmatism from preop. Severe
and extremely steep eyes experienced an average increase in
astigmatism from preop. Conclusions: Epi-on CXL is proven safe
and effective for patients classified as having mild, moderate, or
severe corneal ectatic diseases.
E-Poster Abstracts
Optical Quality in Myopic Patients Operated With
PRK and FemtoLASIK Assessed by Double-Pass
Aberrometry
Presenting Author: Eric Perez-Campagne MD
Coauthors: Hana Landooulsi MD, Damien Gatinel MD PhD
Purpose: To compare objectively the quality of vision assessed
by double-pass imaging in myopic patients operated with PRK
and FemtoLASIK. Methods: Prospective comparative study of
patients who underwent bilateral refractive surgery. 130 eyes of
65 patients were included. Thirty-eight patients underwent PRK,
and 27 underwent FemtoLASIK. The optical quality of each eye
was measured with the Optical Quality Analysis System preoperatively and at 1 and 3 months postoperatively using doublepass aberrometry. The objective scattering index (OSI), the
modulation-transfer function (MTF) cut-off frequency (c/deg),
and the Strehl ratio (SR) were compared at each visit. Results:
Preoperatively mean OSI was 0.54 ± 0.07 in the PRK group and
0.64 ± 0.08 in the FemtoLASIK group (P = .07). Mean MTF
cut-off frequency (c/deg) was 38.56 ± 3.38 in the PRK group and
37.44 ± 2.58 in the FemtoLASIK group (P = .59). One month
postoperatively, mean OSI was 0.73 ± 0.1 in the PRK group and
1.02 ± 0.16 in the FemtoLASIK group (P = .002). Mean MTF
cut-off-frequency (c/deg) was 34.44 ± 2.07 in the PRK group
and 33.32 ± 2.61 in the FemtoLASIK (P = .51). Three months
postoperatively, mean OSI was 0.57 ± 0.06 in the PRK group
and 0.95 ± 0.13 in the FemtoLASIK group (P < .0001). Mean
MTF cut-off frequency (c/deg) was 37.61 ± 2.0 in the PRK group
and 33.57 ± 2.5 in the FemtoLASIK group (P = .01). Mean SR
was significantly larger in the PRK group (0.221 ± 0.01) than in
the FemtoLASIK group (0.186 ± 0.01) (P = .00001). Conclusion:
In the early postoperative period the scatter increases similarly
while the contrast sensitivity decreases in both groups. In the late
postoperative period PRK provides a better optical quality: the
SR is significantly larger and the scatter and the contrast sensitivity remain practically unchanged.
LASIK Enhancement Decision Making Aided by
Sequential, Multioption Algorithm
Presenting Author: Gaurav Prakash MD
Coauthors: Athiya Agarwal MD, Anjum Mazhari MD
Purpose: To develop and evaluate an algorithm for decision
making between flap relift and surface ablation for LASIK
enhancement. Methods: Retrospective analysis of 20 eyes in
each group that underwent enhancement by surface ablation on
flap (SA) and flap relift (FL). The significant parameters were
used to create an algorithm, which was prospectively to decide
between SA and FL for 60 consecutive enhancement cases. The
main outcome measures were visual acuity, refractive error,
and wavefront values at 12 months post-enhancement. Results:
Retrospective analysis showed 5/11 factors to significantly differentiate between SA and RL. Of these, previous ablation,
post-LASIK residual bed thickness (RBT), and estimated postenhancement RBT were used for algorithm creation. Prospective
results showed no difference in the pre-LASIK, post-LASIK and
post-enhancement refractive error between the groups (Group
1, surface ablation, and Group 2, flap relift). For Group 1, the
regression equation between achieved and attempted correction improved from y = 0.71 x +2.2 (R2 = 0.1, P = .16) post-
183
LASIK to y = 1.02 x -0.26,R2 = 0.9, P < .001). For Group 2,
the change was from y = 0.81 x +1.27 (R2 = 0.3, P = .001) to y
= 1.007 x - 0.11 (R2 = 0.95, P < .001).The CDVA significantly
worsened from pre- to post-LASIK status in both groups. Postenhancement, final CDVA was comparable to pre-LASIK status
in Group 1 and significantly better than pre-LASIK status in
Group 2. Conclusions: Successful 1-year outcomes seen with
both groups suggest the usefulness of the algorithm and validates
the decision-making process utilized in the same.
A New, Pachymetry-Based Approach for Diagnostic
Cutoffs for Normal, Suspects, and Keratoconic
Cornea
Presenting Author: Gaurav Prakash MD
Coauthor: Athiya Agarwal MD
Purpose: To analyze association between keratometric and
pachymetric changes in the cornea, and whether it can be used
to create a pachymetric cutoff criteria secondary to keratometric criteria for keratoconus. Methods: In this cross-sectional
study, 1000 subjects presenting to a tertiary care cornea service
underwent Orbscan IIz (Bausch + Lomb) assessment. Results:
Regression analysis showed that simulated keratometry (SimK)
astigmatism was significantly predicted by the minimum corneal
thickness (MCT) and difference between central and minimum
corneal thickness (dCT), mean SimK by MCT and dCT. The
mean minimum corneal thicknesses were 542.5 ± 39.6 µm, 539.9
± 39.2 µm, 524.2 ± 49.5 µm, and 449.3 ± 73.7 µm for flatter
normal (< 44 D) , steeper normal (= 44 D), keratoconus suspect,
and keratoconus, respectively (P < .001). The mean dCTs were
12.2 ± 7.1 µm, 12.4 ± 7.4 µm, 14.4 ± 8.9 µm, and 23.2 ± 10.1
µm for flatter normal , steeper normal, keratoconus suspect, and
keratoconus, respectively (P < .001). Mean and 2 standard deviation cutoff were used to suggest that a cornea having MCT < 461
µm or dCT > 27 µm has only 2.5% chance of being normal and
not a keratoconus suspect or worse. Conclusions: Pachymetric
diagnostic cutoffs can be used as adjuncts to the existing topographic criteria to screen patients of keratoconus suspect and
keratoconus.
184
E-Poster Abstracts
Keratoconus Classification Modeling Using SlitScanning Videokeratography
Presenting Author: Mujtaba A Qazi MD
Coauthor: Jay S Pepose MD
Purpose: To assess the efficacy of specific metrics of slit-scanning
videokeratography to differentiate populations with a clinical
diagnosis of normal, suspect keratoconus, and keratectasia.
Methods: 617 metrics derived from slit-scanning videokeratography (Orbscan, Technolas Perfect Vision; Munchen, Germany),
including Orbscan curvature, elevation, thickness measures, and
previously published algorithms, were calculated for a retrospective data set. This data set (n = 604) included subgroups classified as diseased if they had slitlamp findings characteristic of
keratoconus in the study eye (KCN, n = 338) or fellow eye (KCF,
n = 74) only. Keratoconus suspects (KCS, n = 78) had irregular
videokeratopography, but no characteristic keratoconic slitlamp
findings in either eye. Normal eyes (NRM, n = 114) were sampled from refractive surgery patients with no evidence of ectasia
upon follow-up. For each measure, a nonparametric estimate of
the area under the receiver operator curve (AUC) was calculated,
from which a descriminant model for ectasia diagnosis was
developed. Results: Anterior curvature, anterior elevation, and
posterior elevation metrics had higher AUCs (=0.97) for detecting keratoconic disease (KCN), relative to pachymetry-derived
metrics such as corneal volume or spatial distribution (=0.92).
Combining metrics improved the ability of the algorithm to differentiate subgroups, including for KCF (AUC = 0.99). Conclusion: Evaluation of keratoconus and suspect corneas highlights
the importance of both anterior and posterior videokeratographic analysis in the preoperative assessment of keratorefractive surgery candidates.
Advanced Relational Thickness From Corneal
Tomography for Enhanced Ectasia Detection
Presenting Author: Isaac O Ramos MD
Coauthors: Bernardo Lopes MD, Fernando Faria-Correia MD,
Allan Luz MD, Rosane Correa MD, João Marcelo Lyra MD,
Aydano Machado PhD, Bruno Valbon MD, Marcella Salomão
MD, Renato Ambrosio Jr MD
Purpose: To test a new combination of pachymetric parameters
from corneal tomography to distinguish normal from ectatic
corneas. Methods: One eye randomly selected from 204 normal
patients (Group N), one eye randomly selected from 177 cases
of bilateral clinical keratoconus (Group KC), and 112 eyes with
normal front surface topography from cases with keratoconus in
the fellow eye (Group Forme Fruste of Keratoconus, FFKC) were
included. The Pentacam HR (Oculus; Germany) provided tomographic pachymetric parameters: thinnest point (TP), vertical dislocation from apex of the TP, pachymetric progression indexes
at maximal meridian (PPI Max), and the average of all meridians
(PPI Ave). Fisher linear discriminant analysis was used to optimize a linear combination of these parameters to provide best
possible separation between normal and ectatic corneas. Results:
The combined parameter, named “Advanced Ambrósio’s Relational Thickness” (Adv.ART), obtained 91.07% sensitivity and
92.65% specificity to distinguish N and FFKC (AUC = 0.963)
and 98.9% sensitivity and 99.5% specificity to separate N and
KC (AUC = 0.999). Considering normal and ectatic corneas (KC
+ FFKC), Adv.ART had 95.16% sensitivity, 94.61% specificity,
and AUC of 0.985. The AUC from Adv.ART was statistically
superior (P < .005) to AUC from each parameter individually.
Conclusion: Combination of pachymetric parameters effectively
distinguishes normal from ectatic corneas. Adv.ART provides a
virtually perfect separation of normal corneas from keratoconus,
and enhances the sensitivity for milder forms of ectasia, such as
in cases considered as forme fruste keratoconus.
Clinical Outcomes of Posterior Chamber
Implantable Collamer Lenses and Iris-Fixated Phakic
IOLs
Presenting Author: Jagadesh C Reddy MD
Coauthors: Pravin K Vaddavalli MD, Anil Raj KS MD
Purpose: To evaluate the visual outcomes, efficacy, and safety of
posterior chamber implantable collamer lenses (Visian) and irisfixated phakic IOLs (Verisyse). Methods: Retrospective analysis
of 41 eyes of 35 patients with iris-fixated phakic IOL implantation (Group 1) and 32 eyes of 23 patients with implantable collamer lens implantation (Group 2) for myopia. Results: Preoperative UCVA, BCVA, spherical equivalent (SE), and endothelial cell
density (ECD) were comparable between the 2 groups (P > .05).
Mean logMAR UCVA, BCVA, and SE in Group 1 and Group 2
at 1 month were 0.18 ± 0.14, 0.15 ± 0.15 (P = .17), 0.05 ± 0.07,
0.05 ± 0.07 (P = .78), and -0.19 ± 0.64, -0.33 ± 0.70 (P = .51)
and at 12 months were 0.14 ± 0.13, 0.22 ± 0.23 (P = .51), 0.07 ±
0.08, 0.07 ± 0.12 (P = .37), and -0.14 ± 0.57, -0.21 ± 0.26 (P =
.09), respectively. There was no statistically significant difference
in the ECD either at 1 month (P = .18) or at 12 months (P = .31)
between the 2 groups. Mean safety index was 0.22 ± 0.33, 0.22 ±
0.45 (P = .66), and efficacy index was 0.44 ± 0.52 and 0.90 ±
1.14 (P = .19) at 12 months for Group 1 and Group 2, respectively. Conclusion: Both iris-fixated phakic IOLs and posterior
chamber implantable collamer lenses are equally safe and effective for myopic patients.
Dual Scheimpflug Imaging Parameters in Post-LASIK
Ectasia, Keratoconus, and Normal Eyes
Presenting Author: Jagadesh C Reddy MD
Coauthors: Christopher J Rapuano MD, Kristin M
Hammersmith MD, Parveen K Nagra MD
Purpose: To determine the efficacy of dual Scheimpflug imaging in discriminating post-LASIK ectasia and keratoconus from
normal eyes. Methods: Retrospective evaluation of the para
meters provided by the Galilei dual Scheimpflug analyzer for
post-LASIK ectasia, keratoconus, and normal eyes. The MannWhitney test and receiver-operating-characteristic (ROC) curve
analysis were used to compare the mean values and to calculate
sensitivity, specificity, and accuracy of these parameters. Results:
Sixteen eyes of 10 patients with post-LASIK ectasia, 25 eyes of
20 patients with keratoconus, and 32 normal eyes of 16 patients
evaluated for routine refractive surgery were examined. Steep
anterior (area under the curve-AUC: 0.95) and posterior curvatures (AUC: 0.83) showed high predictive accuracy for keratoconus and post-LASIK ectasia, respectively. Cut-off values of 46 D
and -6.88 D had a sensitivity of 91% and 80% and a specificity
of 91% and 91%, respectively. Total corneal aberrations and
fourth-order RMS were highly specific for keratoconus and postLASIK ectasia, respectively. Conclusions: Anterior curvature
parameters for keratoconus, posterior curvature parameters for
post-LASIK ectasia, and corneal aberrations for both groups had
higher predictive accuracy.
Visual Outcomes, Contrast Sensitivity, and
Stereo Acuity After Corneal Presbyopic LASIK in
Emmetropic Patients
Presenting Author: Dan Z Reinstein MD
Coauthors: Glenn I Carp MBBCH, Timothy J Archer MA,
Marine Gobbe PhD
Purpose: To evaluate the visual outcomes, contrast sensitivity,
and stereo acuity of LASIK with an aspheric micromonovision
protocol in emmetropic patients with presbyopia. Methods: This
retrospective noncomparative case series included 298 eyes of
149 consecutive emmetropic patients with presbyopia treated
with LASIK-induced micro-monovision. The CRS-Master was
used to generate ablation profiles for the MEL80 and flap created by the VisuMax (Carl Zeiss Meditec). The target refraction
was plano for distance (dominant) eyes and between -1.00 and
-1.88 D for near eyes. Patients were followed for 1 year. Emmetropia was defined as SEQ = -0.88 D, sphere = +1.00 D, and cylinder = 1.25 D. Median age was 55 years (range: 44 to 65 years).
Median follow-up was 12.8 months. Uncorrected stereo acuity
was measured in a subset of 25 patients. Results: Outcome measures after all treatments were as follows: Mean accuracy of SEQ
was +0.05 ± 0.39 D, with ±0.50 D in 91% of eyes and ±1.00 D
in 100%. Of distance eyes, 95% achieved uncorrected distance
VA of 20/20 and 100% achieved 20/32. Binocularly, 98% of
patients achieved 20/20 and 100% achieved 20/32. Binocular
uncorrected near VA was J2 in 96% of patients and J3 in 99%,
with a mean increase of 5 lines. Binocularly, 99% of patients
achieved 20/20 and could read J3. No eyes lost =2 lines corrected
distance VA. There was a mean increase of 0.05 logMAR units
in distance corrected near VA. There was a small increase in
mesopic contrast sensitivity at 3 cpd (P = .02) and no change at
E-Poster Abstracts
185
6, 12, or 18 cpd. Postop uncorrected stereo acuity was 100 arcsec in 75% and 200 arcsec in 92% of patients. Conclusion: This
aspheric micromonovision protocol was a well-tolerated and
effective procedure for treating emmetropic patients with presbyopia that did not compromise contrast sensitivity and maintained
functional stereo acuity.
Spectral Domain OCT Analysis of Corneal
Architecture and Epithelial Thickness Profile in
Corneal Collagen Crosslinking
Presenting Author: Karolinne M Rocha MD PhD
Coauthors: David Xu BS, Chen Yan BS, George Waring IV MD,
Bradley Randleman MD, R Doyle Stulting MD PhD, William
Dupps MD, PhD
Purpose: To assess corneal architecture and epithelial thickness
profile of keratoconic eyes after corneal collagen crosslinking
(CXL) using a spectral domain OCT. Methods: Prospective,
randomized clinical trial. Anterior segment OCT (Optovue
RTVue) was used to analyze the corneal morphology of 17 eyes
with keratoconus preoperatively and 1 and 3 months after CXL.
Patients were imaged using the corneal 8-mm cross-line and
6-mm pachymetry scans. A custom-written automated algorithm
was used to automatically segment images based on intensity and
gradient cues to produce 3-D thickness profile of the epithelialBowman transition and stromal layer. Averaged epithelial thickness measurements were made at the corneal apex and 1.5 mm
and 2 mm offset from the corneal apex. Results: Epithelial thickness in the keratoconus showed a standard deviation in the vertical and horizontal axis ranging from 3.25 to 22.55 µm and from
2.72 to 15.98 µm, respectively. Epithelium was significantly
thickened 1.5 to 2.5 mm below the corneal apex (P < .001).
Epithelial thickness at the corneal apex was a mean ± STD of
49 ± 13 µm preoperatively, 51 ± 5.0 µm 1 month, and 50 ± 7.7
µm 3 months postoperatively. Preoperative averaged epithelial
thickness measurements were statistically thinner at the corneal
apex and in the 1.5-mm and 2-mm offset locations compared to
1 month after CXL (P = .017, P = .001, P = .007, respectively).
At 3 months significant epithelial thickness were found at 2 mm
from the corneal apex. Conclusions: Analysis of the epithelial
thickness profile can be used as an adjunctive tool to estimate the
minimum corneal thickness after epithelial debridement and to
better understand corneal curvature changes after CXL.
186
E-Poster Abstracts
Quantification of Refractive Error After IOL
Implantation in Myopic Eyes and Deviation of the
Formulae
Corneal Collagen Crosslinking in Patients With a
Preop Diagnosis of Pellucid Marginal Degeneration
Presenting Author: Alvaro Rodríguez Ratón MD
Coauthors: Parag Majmudar MD, David A Wallace MD, Jay
Schwartz, MD, Sandy T Feldman MD, Dan Goodman MD
Coauthors: Javier Orbegozo Garate MD, Iñaki Basterra
Optician
Purpose: To analyze the refractive error after IOL implantation
in myopic patients and deduce the error that would have generated the use of different formulas. Methods: We retrospectively
analyzed the refractive outcome of 101 eyes of 69 myopic
patients operated by phacoemulsification and IOL implantation
between 2009 and 2011 at 2 different medical centers. All had
axial length greater than 27 mm. IOL power had been approximated prior to surgery by formulas obtained from non-contact
laser biometer IOLMaster (Zeiss). We calculated deviation from
emmetropia and the most accurate formula. Results: 69.3% of
the operated eyes had a residual refractive error within half diopter range, collecting 89.1% within the diopter of deviation. Average deviation from correct IOL power was +1.99 D for HofferQ,
+1.58 D for Holladay; +1.31 D for SRK-T, and +0.86 D for Haigis. The differences were greater among formulas in the negative
IOL group. Conclusion: To our knowledge, the Haigis formula
calculates the most accurate IOL power in the great myopic.
Constant customization should improve this accuracy.
Evaluation of Epithelial-On Corneal Collagen
Crosslinking in Young Patients
Presenting Author: Roy Scott Rubinfeld MD
Purpose: To evaluate the safety and efficacy of epithelial-on
(epi-on) corneal collagen crosslinking (CXL) in patients with a
preoperative diagnosis of pellucid marginal degeneration (PMD).
Methods: Patients with a preop diagnosis of PMD who underwent CXL met inclusion criteria and were evaluated. Outcome
measures included UCVA and BSCVA, manifest astigmatism,
Atlas topography measures, and Oculus Pentacam measures.
These measures were compared to preop values. Results: Seven
eyes of 4 patients met inclusion criteria. Fifty-seven percent
of eyes were male and 100% of eyes had a preop diagnosis of
PMD. Twenty-nine precent of eyes were reported to have never
worn contact lenses preop, and 14% of eyes were reported to
have worn soft contact lenses. Compared to preop UCVA, 20%
of eyes gained 1 or more lines and 40% of eyes experienced no
change. Compared to preop BSCVA, 29% of eyes gained 1 or
more lines and 71% of eyes experienced no change. Eyes experienced an average improvement (decrease) in manifest astigmatism of -1.12 D and an average decrease in Magellan mean
K of -0.65 D. Eyes experienced no average change in Pentacam
keratometry astigmatism or Pentacam pachymetry apex when
compared to preop values. Conclusion: Epi-on CXL appears to
be safe and effective for eyes with a preop diagnosis of pellucid
marginal degeneration.
Presenting Author: Roy Scott Rubinfeld MD
Coauthors: Marwa Adi MD, Erik Letko MD, Parag Majmudar
MD, Gaston Lacayo MD, Gabriela Perez BS, William Trattler
MD
Purpose: To evaluate the safety, efficacy, and outcomes of
epithelial-on corneal collagen crosslinking (CXL) in patients age
younger than 35 diagnosed with preoperative ectatic corneal
disease. Methods: Eyes of patients aged younger than 35 who
were treated with epithelial-on CXL were evaluated. Outcome
measures included UCVA, BSCVA, astigmatism measures, Pentacam data, and topography data. Results: Ninety-one eyes met
inclusion criteria; 70% of eyes were male and 82% of eyes had
a preoperative diagnosis of keratoconus. Average time of latest
follow-up was 7.12 months. Preoperatively, 82% of eyes were
20/400 or better uncorrected, and 68% of eyes had a BSCVA of
20/40 or better. Fifty-one percent and 44% of eyes had improvements in UCVA and BSCVA, respectively, 40% of eyes experienced no change in UCVA by the latest follow-up visit, and 43%
of eyes experienced no change in BSCVA by the latest follow
up visit. Postoperatively, 82% and 68% of eyes had a UCVA
of 20/400 or better and a BSCVA of 20/40 or better. Patients
experienced an average change of -0.75 D of topography steep
K and an average increase of 0.01 D in Magellan mean K at the
latest visit from preop. Patients experienced an average decrease
improvement in Pentacam keratometry astigmatism of -0.02 D
and in manifest astigmatism of -0.58 D. Conclusions: Epithelialon CXL is proven safe and effective for patients that are younger
than 35 and diagnosed with corneal ectatic disease.
Results and Complications of Femtosecond LaserAssisted Intrastromal Ring Implants Over 4-Year
Follow-up
Presenting Author: Mahipal S Sachdev MD
Coauthors: Charu Khurana MS, Ritika Sachdev MS, Ramendra
Bakshi MS, Hemlata Gupta MS
Purpose: To evaluate results and complications of intrastromal
ring implants in 65 eyes with keratoconus and post-LASIK
keratectasia over a span of 4 years. Methods: Sixty-five eyes of
47 patients underwent intrastromal ring implantation with a
femtosecond laser. UCVA and BCVA were measured at 1, 3, 6,
12, and 24 months postop. Refraction, corneal topography, and
anterior segment OCT were done preop and postop. Results:
The mean preop UCVA and BCVA were 0.1 and 0.4, and the
mean postop UCVA and BCVA were 0.4 and 0.7, respectively.
One case of anterior chamber perforation was seen on the first
postop day and the segments were explanted. One eye had a corneal melt after 3 months of surgery following a recurrent inflammatory reaction where the segment had to be removed. White
cell reaction was seen in 3 eyes which responded to short course
of steroids. Conclusion: Intrastromal ring segments are useful in
the management of patients with keratoconus and post-LASIK
ectasia where other laser procedures are contraindicated. However, complications can occur which need to be identified and
treated early, including explantation of segments in some cases.
Distribution of Keratoconus Match Index and
Keratoconus Match Probabilities in a Normal
Refractive Surgery Population
Presenting Author: Youjia Shen MD
Coauthors: Eser Adiguzel PhD, Mark Cohen MD, Avi
Wallerstein MD
Purpose: To determine the normal distribution of keratoconus
match index (KMI) and keratoconus match probabilities (KMP)
scores in a population of patients presenting for laser vision correction (LVC). Methods: All patients presenting for LVC had
ocular biomechanical properties measured by the Ocular Response
Analyzer (ORA). Virgin eyes with good waveform scores (> 6.5)
were examined with ORA software version 3.01, providing the
new KMI and KMP indices. These are derived from analysis of
waveforms from 5 clinical populations: normal, suspect keratoconus (KC), mild KC, moderate KC, and severe KC. Distribution
and ranges were determined for KMI and KMP indices. Results:
KMI and KMP scores for 18,179 eyes were analyzed. The average
KMI was 0.94 ± 0.26, range of -0.01 to 3.55. KMP distributions
were 99.9, 95.9, 82.6, 6.8, and 0.06% with characteristics matching normal, suspect, mild, moderate, and severe KC populations.
No waveform had more than 68, 65, 33, and 4% similarity to
the KC populations. 4.1% were 100% normal, while 13.3% had
only suspect KC characteristics that were 4% suspect KC or less
and had a minimum KMI of 1.181. Any waveforms with over 4%
suspect KC characteristics matched to other KC groups as well
and had KMI values less than 1.181. KMI was directly proportional to KMP in normal and indirectly proportionally to KMP in
suspect, mild, moderate, and severe KC (P < .001). Conclusion: A
small percentage of eyes presenting for LVC were found to match
to moderate and severe KC waveform characteristics. A large percentage of waveforms contain characteristics of suspect and mild
KC. It would be important to match these findings to topographies
in order to determine the clinical utility of KMI and KMP scores.
Surgical Efficiency of Femtosecond Laser Refractive
Lens Surgery vs. Conventional Phacoemulsification
Presenting Author: Felipe A Soria MD
Coauthors: Ahmed a Abdou PhD, Jorge L Alio MD PhD, Jamie
Javaloy PhD, Roberto Frenandez-Buenaga MD, Pablo Peña
Garcia MS
Purpose: To compare the incision quality, nuclear fragmentation
efficacy, and IOL centration between femtosecond laser refractive
lens surgery (FLRLS) and contralateral conventional phacoemulsification of the same patients. Method: In a randomized controlled contralateral comparative study of 25 patients with bilateral cataract, one eye was operated with FLRLS while the other
one with conventional phacoemulsification. Corneal higher-order
aberrations (HOAs) were analyzed for evaluation of the incision
types. A 2.2-mm incision was used for the phacoemulsification.
Operative average ultrasound power, total phacoemulsification
time (TPT), and effective phacoemulsification time (EPT) were
assessed for nuclear fragmentation. IOL centration evaluation
was done with internal HOA coma analysis. Data was recorded
for 1-month follow-up. Results: Mean age of patients was 70
± 9.3 years. No significant changes in the total corneal HOAs
between the 2 groups were found, but the mean corneal spherical
aberration of FLRLS was less than that of the conventional group
at the first postoperative day (0.18 ± 0.321 µm, 0.31 ± 0.08 µm;
E-Poster Abstracts
187
P = .2). Inraoperative means of ultrasound power, TPT and EPT
of the FLRLS were less than the conventional means (10.5 ±
7.5%, 11.1 ± 6.1%; P = .6) (30.7 ± 20.9, 39.1 ± 21.7 sec.; P = .1)
and (3.3 ± 2.8, 4.2 ± 4.4 sec.; P = .7). The internal 6-mm coma
of the FLRLS was also less than the conventional group after 1
month of surgery (0.39 ± .23, 0.46 ± .30; P = .5). Conclusion:
FLRLS provides good incision, efficient nuclear fragmentation,
and precise IOL centration and could be superior to conventional
phacoemulsification as it induces fewer changes in spherical and
coma aberration at 1 month follow-up. Larger data and longer
follow-up are recommended for more significant evaluation.
Study of Axial Length Before and After Myopic
LASIK With the IOLMaster
Presenting Author: Eugene Tay MBBS
Coauthors: Xiang Li PhD, Howard Gimbel MD, Geoffrey Kaye
MD
Purpose: To assess the relationship between theoretical ablation
depth and axial length change after LASIK. Methods: Ninetynine eyes were examined preoperatively and 1 and 3 months
after LASIK. Results: Mean (SD) spherical equivalent before
LASIK was -4.06 (1.91) D. Mean (SD) ablation depth was 83.13
(30.31) µm. Mean (SD) postoperative axial length of 25.11
(0.14) mm at 1 month was significantly shorter than mean (SD)
preoperative axial length of 25.20 (0.14) mm (P < .001) with
no subsequent change thereafter (P = .450). An increase in ablation depth of 1 µm led to a decrease in axial length of 0.00118
(0.00005) mm. Ablation depth correlated strongly with change
in axial length (adjusted R² = 0.9039). Conclusion: The IOLMaster showed a decrease in axial length after LASIK that correlated
well with theoretical ablation depth.
OCT-Guided Femtosecond Laser Corneal Surgery
Presenting Author: Minoru Tomita MD
Purpose: To evaluate the safety and efficacy of an Optical Coherence Tomography (OCT) guided femtosecond laser in corneal
surgery. Methods: Thirty-two eyes of 16 patients underwent
LASIK and 13 eyes of 13 patients underwent post-LASIK corneal inlay implantation. After applanating a suction ring on the
cornea, the corneal image was visualized using the built-in OCT
system. Using this preoperative image, the following were verified; 1) Bowmans layer for LASIK patients and 2) The location of
the previous LASIK flap relative to the new pocket to be created
for post-LASIK corneal inlay patients. After LASIK flap/corneal
pocket creation, the postoperative corneal image was visualized again. Results: 1) For LASIK patients, Bowmans layer was
visualized with the preoperative OCT image and a safe distance
between Bowmans layer and the flap interface was confirmed. 2)
For patients who underwent post-LASIK corneal inlay implantation, the original LASIK flap was visualized with the preoperative OCT image to confirm a safe distance between the original
flap and the pocket. Postoperative OCT images were the same
as predicted preoperatively for both patient groups. All flaps
and pockets were created safely and without any complications.
Conclusion: Using the added function of OCT, surgeons are able
to visualize and confirm safe surgical parameters prior to corneal
flap creation for LASIK and for corneal pocket making for post
LASIK patients. Using OCT, surgeons are able to increase the
safety and accuracy of corneal surgery.
188
E-Poster Abstracts
Intraoperative Power Selection and Axis Orientation
of Toric IOL Using a Real-Time Wavefront
Aberrometer
Crosslinking in Patients With Previous Intacs
Presenting Author: Dan B Tran MD
Coauthors: Charles J Kaiser MD, Gaston Lacayo MD, Carlos
Buznego MD, Eric Liss MD, Gabriela Perez BS
Purpose: To report the refractive outcomes of toric IOLs using
the aphakic measurements of an intraoperative wavefront aberrometer to aid in the power selection and axis placement of toric
IOLs with the real-time pseudophakic confirmation of the axis
orientation. Methods: Retrospective consecutive case series study
of 50 eyes with toric IOL implants guided by an intraoperative
wavefront aberrometer. The aphakic measurement was used
to help with the toric IOL power and cylinder selection. The
pseudophakic measurement was performed at the end of the
surgical procedure to confirm the proper orientation of the toric
IOL with additional intraoperative IOL rotations performed as
needed. The postop residual cylinder manifest refractions power
and axis at 1 month were reported. Results: The residual manifest cylinder measurement at 1 month was 0.52 ± 0.31 D using
the toric IOL power and cylinder selection suggested by the aberrometer with toric IOL orientation confirmation using the aberrometer pseudophakic measurement. Conclusions: Intraoperative wavefront aberrometer is an effective method of toric IOL
power and cylinder selection using the aphakic measurement
with a real-time confirmation of the proper toric IOL axis orientation. Intraoperative toric IOL rotation to optimize the IOL
orientation helps to improve the final refractive outcomes.
Crosslinking in Older Patients
Presenting Author: William B Trattler MD
Coauthors: Roy S Rubinfeld MD, Valerie Seligson OD, Neil F
Martin MD, Gabriela Perez BS, Eric Liss MS, Marwa Adi MD
Purpose: To evaluate the safety, efficacy, and outcomes of epithelial-on (epi-on) corneal collagen crosslinking (CXL) in patients
age 35 and older diagnosed with preoperative ectatic corneal
disease. Methods: Eyes of patients aged 35 and older that were
treated with epi-on CXL were evaluated. Outcome measures
included UCVA, BSCVA, astigmatism measures, Pentacam data,
and topography data. Results: 102 eyes met inclusion criteria.
Seventy percent of eyes were male and 69% of eyes had a preoperative diagnosis of keratoconus. Average time of latest followup was 6.2 months. Preoperatively, 60% of eyes were 20/400
or better uncorrected and 51% of eyes had a BSCVA of 20/40
or better; 39% and 40% of eyes had improvements in UCVA
and BSCVA, respectively. Fifty-five percent of eyes experienced
no change in UCVA by the latest follow-up visit; 45% of eyes
experienced no change in BSCVA by the latest follow-up visit.
Postoperatively, 72% and 62% of eyes had a UCVA of 20/400
or better and a BSCVA of 20/40 or better. Patients experienced
an average change of +0.6 D of topography steep K and an average decrease of 0.6 D in Magellan mean K at the latest visit from
preop. Patients experienced an average improvement in Pentacam keratometry astigmatism of -0.03 D and in manifest astigmatism of -0.58 D. Conclusions: Epithelial-on CXL is proven
safe and effective for patients who are age 35 and older and diagnosed with corneal ectatic disease.
Purpose: To evaluate the safety and efficacy of corneal collagen
crosslinking (CXL) in patients with previous Intacs. Methods:
Patients who were implanted with Intacs prior to CXL were
evaluated. Outcome measures were compared to preoperative
measures and included UCVA and BSCVA, astigmatism, Oculus
Pentacam measures, and Atlas topography measures. Results:
Four eyes of 2 patients met inclusion criteria. Both patients were
male with a diagnosis of keratoconus bilaterally. One patient
reported never wearing contact lenses, while the other patient
reported current hybrid contact lenses preop. One patient was
over the age of 35 and was considered an older adult. Average
follow-up time was 7.8 months. Seventy-five percent of eyes
gained 1 or more lines of UCVA from preop, and 100% of eyes
gained 1 or more lines of BSCVA from preop; 50% of eyes had a
UCVA of 20/100 or better preop and 75% of eyes had a UCVA
of 20/100 or better postop. Twenty-five percent of eyes had a
BSCVA of 20/30 or better preop and 50% of eyes had a BSCVA
of 20/30 or better postop. Both patients experienced an improvement (decrease) in astigmatism bilaterally from preop. The average change in manifest astigmatism was -1.57 D and the average
change in Pentacam astigmatism -0.4 D. Both patients experienced an average decrease in Magellan mean K (topography).
Conclusions: Epi-on CXL is proven safe and effective for patients
with previous Intacs.
Comparative Evaluation of PRK and LASIK for Vision
Enhancement After Implantation of Presbyopic IOL
Coauthors: Charles J Kaiser MD, Frank Spektor MD, Eric A Liss
MD, Remigio Flor MD
Purpose: The study was conducted to compare visual outcomes
in patients who received laser enhancement (PRK or LASIK)
following phacoemulsification with presbyopic IOL implants.
Methods: Eyes (n = 120) that received a presbyopic IOL unilaterally or bilaterally followed by a laser enhancement with PRK or
LASIK were included in this study. All enhancements between
April 2006 and May 2011 were included for analysis. Results:
120 eyes were evaluated; 109 eyes received PRK (average age =
67 years old) and 11 eyes received LASIK (average age = 62 years
old). Enhancements were performed at a minimum of 3 months
post-phacoemulsification. Nineteen percent of PRK patients and
27.3% of LASIK patients had uncorrected distance (UCDVA)
of 20/30 or better pre-enhancement; 82.9% of PRK patients
and 81% of LASIK patients had UCDVA of 20/30 or better
post-enhancement. Fifty-six of 109 eyes that underwent PRK
(51.4%) had =1 D of astigmatism preoperatively, compared to
14/94 eyes (14.9%) post-laser vision correction. Ten of 11 eyes
that underwent LASIK (90.9%) had =1 D of astigmatism preoperatively, compared to 1/11 eyes (9.1%) post-laser vision correction. Conclusion: This preliminary comparison of PRK and
LASIK for improving vision in patients who are post-presbyopic
IOL implantation suggests that both techniques can effectively
improve visual acuity.
Risk Factors for Retreatment After LASIK: ThreeYear Follow-up in a Hispanic Population
Presenting Author: Jorge E Valdez-Garcia MD
Purpose: To asses the correlation of some risk factors for LASIK
retreatment in a Hispanic population with a 3-year follow-up.
Methods: A retrospective analysis was performed on 482 LASIK
procedures of 241 patients at the Insituto de Oftalmología y
Ciencias Visuales Tec Salud (México). Inclusion criteria were age
over 18 years, a refraction with spherical component in the range
of -11.00 D to 6.50 D, a cylindrical component between 0.00
D and 6.50 D, and 36-month follow-up. Patients with ophthalmological pathologies were excluded. Retreatment was defined
as a second LASIK procedure due to residual refractive error.
Procedures were performed by the same surgeon with a Technolas-217 Excimer Workstation (Technolas Perfect Vision GmbH;
München, Germany), Hansatome Microkeratome (Bausch +
Lomb; Rochester, NY, USA). Statistical analysis was performed
with the SPSS software. Results: 68.5% of recruited patients had
myopia, 26.76% had hyperopia, and 4.97% had astigmatism.
Visual acuity after the primary procedure was equal to or better
than 20/40 in 81.1% of patients and 20/20 in 72.2%. Retreatment was performed in 33 eyes (6.85%). Of these, 15 (45.5%)
were myopic, 17 (51.5%) were hyperopic, and 1 (3%) required
astigmatic corrections. Our results showed an association
between undercorrection and increasing degrees of myopia (P =
.004 m). Hyperopia had an increased relative risk of 3.18 respective to myopia. Age over 40 years old was also significantly associated with undercorrection (P = .006). Conclusions: Although
we had a small proportion of retreated patients (6.85%), our
results suggest that in our population, age is the most important
factor associated with retreatment. Also our results suggested
a correlation with severe myopia. We were able to establish an
increased relative risk for hyperopia.
Internal High-Order Ocular Aberrations After
Implantation of a Toric IOL
Presenting Author: Paolo Vinciguerra MD
Coauthors: Mario Romano MD, Massimo Vitali Orthoptist
Purpose: To prospectively evaluate internal high-order ocular
aberrations (HOA) before and after implantation of an aspheric
toric IOL. Methods: All eyes underwent HOA evaluation with
Nidek OPD aberrometer preoperatively and 3 weeks after surgery for a 3-, 4-, and 5-mm pupil. Results: Twelve cataract eyes
of 7 patients underwent 2.2-mm incision surgery and insertion
of a Zeiss AT TORBI 709 M toric IOL, with mean power of
+16.33 ± 7.57 D and -2.75 ± 0.27 D cyl. Follow-up was 17.00 ±
14.21 days. Internal spherical aberration decreased or remained
unchanged. Internal trefoil decreased for all pupil diameters.
Internal coma decreased for 3- and 4-mm, and increased for
5-mm pupil. P was < .05. Postoperative UCVA was -0.05 ± 0.51
logMar. Conclusion: This aspheric toric IOL improved visual
acuity and seldom worsened HOA.
E-Poster Abstracts
189
Microdistortions in Bowman Layer of Femtosecond
Small-Incision Lenticule Extraction: A Fourier
Domain OCT Study
Presenting Author: Peijun Yao MD
Coauthors: Jing Zhao MD, Meiyan Li MD, Yang Shen MD,
Zixian Dong MD, Xingtao Zhou MD
Purpose: To investigate the microdistortions in the Bowman
layer after femtosecond laser small-incision lenticule extraction
(SMILE) and its risk factors and potential influences. Methods:
Fifty-two eyes of consecutive 29 SMILE patients were enrolled.
The surgeries were performed using VisuMax laser system
with a superior 4.2-mm incision. The microdistortions in Bowman layer were observed and counted in 4 meridians using a
Fourier-domain OCT at 1 day, 1 week, 1 month, and 3 months.
Another 38 eyes of 20 femtosecond-assisted LASIK patients were
observed at 1 day postoperatively as a control group. Results:
Microdistortions were detected using OCT but with no detectable striae in slitlamp microscopy in 46 eyes (88.5%) at 1 day
after SMILE. The same phenomenon was observed in 16 eyes
(42.1%) after LASIK. More microdistortions were detected after
SMILE than after LASIK (P = .006, student test), more in central
than in peripheral (P < .001, paired t test), more in inferior than
in superior (P < .001, paired t test). Multivariate linear regression
analysis showed correlations with surgery order (R = -0.66, P <
.001), lenticule thickness (R = 0.59, P < .001), and preoperative
cornea curvature (R = 0.302, P = .009). The microdistortions
decreased with the follow-up time (P = .12). After adjusting the
spherical equivalence of refraction, the postoperative visual acuity was correlated with the counting of microdistortions only at
1 month (R = -0.15, P < .001) within the follow-up. Conclusion:
There are OCT detectable microdistortions in the Bowman layer
after SMILE surgery. They may be related to preoperative corneal shape and lenticule thickness and may have impact on the
visual performance.
191
Financial Disclosure
The Academy’s Board of Trustees has determined that a financial relationship should not restrict expert scientific, clinical, or
nonclinical presentation or publication, provided that appropriate disclosure of such relationship is made. As an Accreditation
Council for Continuing Medical Education (ACCME) accredited
provider of CME, the Academy seeks to ensure balance, independence, objectivity, and scientific rigor in all individual or jointly
sponsored CME activities.
All contributors to Academy educational activities must disclose any and all financial relationships (defined below) to the
Academy annually. The ACCME requires the Academy to disclose the following to participants prior to the activity:
• any known financial relationships a meeting presenter,
author, contributor, or reviewer has reported with any
manufacturers of commercial products or providers of
commercial services within the past 12 months
• any meeting presenter, author, contributor, or reviewer
(hereafter referred to as “the Contributor”) who report
they have no known financial relationships to disclose
For purposes of this disclosure, a known financial relationship is defined as any financial gain or expectancy of financial
gain brought to the Contributor or the Contributor’s family,
business partners, or employer by:
• direct or indirect commission;
• ownership of stock in the producing company;
• stock options and/or warrants in the producing company,
even if they have not been exercised or they are not currently exercisable;
• financial support or funding from third parties, including
research support from government agencies (e.g., NIH),
device manufacturers, and/or pharmaceutical companies;
or
• involvement in any for-profit corporation where the Contributor or the Contributor’s family is a director or recipient of a grant from said entity, including consultant fees,
honoraria, and funded travel.
The term “family” as used above shall mean a spouse, domestic partner, parent, child or spouse of a child, or a brother, sister,
or spouse of a brother or sister, of the Contributor.
Category
CodeDescription
Consultant / Advisor
C
Consultant fee, paid advisory
boards or fees for attending a
meeting (for the past one year)
Employee
E
Employed by a commercial
entity
Lecture fees
L
Lecture fees (honoraria), travel
fees or reimbursements when
speaking at the invitation of a
commercial entity (for the past
one year)
Equity owner
O
Equity ownership/stock options
of publicly or privately traded
firms (excluding mutual funds)
with manufacturers of commercial ophthalmic products or
commercial ophthalmic services
Patents / Royalty
P
Patents and/or royalties that
might be viewed as creating a
potential conflict of interest
Grant support
S
Grant support for the past one
year (all sources) and all sources
used for this project if this form
is an update for a specific talk
or manuscript with no time
limitation
192
2012 Refractive Surgery Planning Group
Financial Disclosures
David R Hardten MD
Bausch + Lomb: C
Bio-Tissue, Inc.: C
Calhoun Vision Inc.: S
ESI, Inc.: C
Oculus, Inc.: L
TLC Vision: C
Topcon Medical Systems: S
AAO Staff
Brandi Garrigus
None
Ann L’Estrange
None
Melanie Rafaty
None
Michael C Knorz MD
Debra Rosencrance
Alcon Laboratories, Inc.:C,L
FourSight Labs LLC: C,O
LenSx, Inc.: C,O
Optical Express, Inc.: C
None
Amar Agarwal MD
Dr. Agarwal’s Pharma: O
SLACK, Incorporated: P
Staar Surgical: C
Thieme Medical Publishers: P
Daniel S Durrie MD
Abbott Medical Optics: C,L ,S
AccuFocus: C,L,O
Alcon Laboratories, Inc.: C,L,O,S
Avedro: L,O
NexisVision: C,L,O,S
Revital Vision: O
Wavetec: C,L,O,P
Ziemer: C.L
Sonia Yoo MD
Alcon Laoratories, Inc: C,L
Allergan, Inc: S
SLACK, Incorporated: C,L
Transcend: C
Beth Wilson
None
Faculty Financial Disclosures
Noel A Alpins MD FACS
None
Assort: P
Natalie A Afshari MD
Alcon Laboratories, Inc.: C,L
WaveLight AG: L
National Eye Institute: S
Research to Prevent Blindness: S
AcuFocus, Inc.: C,L
Allergan, Inc.: C,L
Amar Agarwal MD
Dr. Agarwal’s Pharma: O
Staar Surgical: C
Iqbal K Ahmed MD
Abbott Medical Optics: L
Alcon Laboratories, Inc.: C,L,S
Aquesys: C,S
Carl Zeiss Meditec: C,L,S
Clarity: C,S
Endo Optiks, Inc.: C
Glaukos Corp.: C,S
Iridex: C
Ivantis: C,L,S
Merck: C,L,S
Neomedix: L
New World Medical, Inc.: L
Pfizer, Inc.: C,L,S
Transcend Medical: C
Jorge L Alio MD PhD
AcuFocus, Inc.: S
Akkolens: C,S
Bausch + Lomb Surgical: C,S
Hanita Lenses: C
Mediphacos: C
Novagali: S
Nulens: C,O
Oculentis: C,S
Physiol: C
Presbia: C
Santen, Inc.: C
Schwind eye-tech-solutions: L,S
Springer Verlag: P
Tedec Meiji: C
Tekia, Inc.: P
Thea: S
Topcon: C
Vissum Corp.: E,O
Moria: P
Schwind eye-tech solutions: P
Gerd U Auffarth MD
Daniel H Chang MD
Abbott Medical Optics: C,S
Bausch + Lomb Surgical: S
Carl Zeiss Meditec: C,S
Rayner Intraocular Lenses, Ltd.: C,S
Schwind eye-tech-solutions: C
Technolas: L,S
Allergan, Inc.: L
Scott D Barnes MD
Staar Surgical: L
Peter James Barry MD
None
George Beiko MD
Michael W Belin MD
David F Chang MD
Allergan, Inc.: L
Calhoun Vision Inc.: O
Clarity: C,O
Eyemaginations Inc.: P
Glaukos Corp.: S
ICON bioscience: O
LensAR: C,O
One Focus Ventures: O
PowerVision, Inc.: O
Revital Vision: O
Transcend Medical: C,O
Oculus, Inc: C,L
John P Berdahl MD
Technolas Perfect Vision: L
Allergan, Inc.: L
Ista Pharmacuticals: C
Perry S Binder MD
AcuFocus, Inc.: C,L,O
Outcomes Analysis Software, Inc.: P
Stroma: C
Arturo S Chayet MD
Calhoun Vision, Inc.: C
Nidek, Inc.: C
Xiangjun Chen MD
None
Y Ralph Chu MD
Camille J R Budo MD
Allergan, Inc.: C,L
Glaukos Corp.: C
Ista Pharmacuticals: C,L
Lifeguard Health: C
Ocular Therapeutix: C
Ocusoft: C
Powervision: C
Revision Optics: C
Carl Zeiss Meditec: C,L
Ophtec, BV: C,L
Robert J Cionni MD
Tenley N Bower MD
None
Rosa Braga-Mele MD
Allergan: C,L
Morcher GmbH: P
WaveTec Vision: C
193
194
Joseph Colin MD
Burkhard Dick MD
Damien Gatinel MD
Addition Technology: C
Bausch + Lomb: C
Calhoun Vision Inc.: O
Morcher GmbH: P
Ocular Surgery News: C
Oculus, Inc.: P
AcuFocus, Inc.: L
Bausch + Lomb: L
Chibret International: L
Nidek, Inc.: C,L
Reichert Ophthalmic Instruments: L
Technolab: L
David A Goldman MD
AcuFocus, Inc.: C
Aquesys: C
CRST: C
Glaukos Corp.: C
Inspire Pharmaceuticals, Inc.: C,P
Lensx: C
Odyssey: C
Pfizer, Inc.: C
QLT Phototherapeutics, Inc.: C
TLC Laser Eye Centers: L,O
Truevision: C,O
Wavetec: C
Allergan, Inc.: C
Lumenis, Inc.: C
Paul J Dougherty MD
Schwind eye-tech-solutions: C
Ziemer Ophthalmics: C
Alan S Crandall MD
Allergan, Inc.: L
AqueSys: C
ASICO: C
eSinomed: C
Glaucoma Today: C
Glaukos Corp.: C
iScience: C
Ivantis, Inc.: C
Journal Cataract Refractive Surgery: C
Mastel Surgical: C
Ocular Surgery News: L
Omeros Corp.: C
Vimetrics: C
Hoya Surgical Optics: C
Optimedica: C,O,P
Elizabeth A Davis MD
Allergan, Inc.: L
Refractec: O
SARcode Bioscience: C
James A Davison MD
Steven J Dell MD
Allergan, Inc.: C
Bausch + Lomb Surgical: C,O,P
Optical Express: C
Tracey Technologies, Corp.: C,O
Uday Devgan MD
Accutome Inc.: L,P
Alcon Laboratories, Inc.: L,O
Haag-Streit: L
Hoya Surgical Optics: C,L
Ista Pharmacuticals: C,L,O
SLACK, Incorporated: L
Specialty Surgical: O
Storz Instruments from Bausch + Lomb:
C
Deepinder K Dhaliwal MD
None
Lenstec, Inc.: C,L,O
Nidek, Inc.: L
Revision Inc.: C
Staar Surgical: L
Gunther Grabner MD
AcuFocus, Inc.: L,S
Polytech: C
José L Güell MD PhD
Calhoun Vision, Inc.: O
Carl Zeiss Inc.: C
Ophtec, BV: C
Farhad Hafezi MD PhD
D Rex Hamilton MD
None
Reichert, Inc.: L
Ziemer: L
Daniel S Durrie MD
Sadeer B Hannush MD
Accelerated Vision: C,L,O
Alcon Laboratories, Inc.: C,L,O,S
Allergan: L
Avedro: L,O
NexisVision: C,L,O,S
Revital Vision: O
Wavetec: C,L,O,P
Ziemer: C,L
None
Richard J Duffey MD
David R Hardten MD
Alaa M ElDanasoury MD
Bausch + Lomb: C
Bio-Tissue, Inc.: C
Calhoun Vision, Inc.: S
ESI, Inc.: C
Oculus, Inc.: L
TLC Vision: C
Topcon Medical Systems: S
Nidek, Inc.: C
Staar Surgical: C
Thomas M Harvey MD
William J Fishkind MD FACS
LensAR: C
Neil J Friedman MD
Allergan: L
Bausch + Lomb: L
DigiSight: C,O
OptiMedica: C,O
Oraya: C,O
Lenstec, Inc.: C
Merck & Co., Inc.: L
TLC Laser Eye Centers: O
Bausch + Lomb: C
Massachusetts Eye and Ear Infirmary: P
Peter S Hersh MD
Soosan Jacob FRCS
Ronald R Krueger MD
Addition Technology: S
Avedro, Inc.: C
Synergeyes, Inc.: S
None
Jesper Hjortdal MD
Alcon Laboratories, Inc.: CL
Clarity Medical: C
LensAR: O
Presbia, Inc.: C
Avedro: C
KeraMed, Inc.: L
WaveLight AG: L
Kenneth J Hoffer MD FACS
Haag-Streit : P
Oculus, Inc.: P
Ziemer: P
Choun-ki Joo MD
None
None
AcuFocus, Inc.: C
Carl Zeiss, Inc.: C
Oculus, Inc.: C
Wavetec: C
None
Simon P Holland MD
Allergan: L
Bausch + Lomb: L
Mike P Holzer MD
Bausch + Lomb: C
Rayner Intraocular Lenses, Ltd.: L,S
Technolas Perfect Vision GmbH: C,L,S
Abbott Medical Optics: C,L,O,P
Allergan, Inc.: C
Bausch + Lomb Surgical: C,L,O
Essex Woodlands Health Ventures: C,L
Glaukos Corp.: S
IOP, Inc.: C,L,S
Ivantis: C
Ocular Therapeutix: C,L,O,S
ReVision Optics: C
Sight Sciences: C,O
Visiogen, Inc.: C,L,S
Vista Research: C
Vistakon Johnson & Johnson
Visioncare, Inc.: C,P,S
Aylin Kiliç MD
None
Terry Kim MD
Bausch + Lomb: C,L
Ocular Systems, Inc.: C
Ocular Therapeutix: C,O
Powervision: C,O
SARcode Bioscience: C
Stephen D Klyce PhD
Acufocus: C
Clinical Research Consultants: C
LensAR: C
Nexis Vision: C
Nidek, Inc.: C
NTK Enterprises: C
Ocularis Pharma: C
Topcon Medical Systems: C
Michael C Knorz MD
FourSight Labs LLC: C,O
LenSx, Inc.: C,O
Optical Express, Inc.: C
Douglas D Koch MD
Carl Zeiss Meditec: P
Optovue, Inc.: C,L,O,P,S
NuLens: C
Optimedica: O
Ziemer: S
Thomas Kohnen MD PhD FEBO
Carl Zeiss Meditec: C,L
Bausch + Lomb Surgical: L,S
Hoya: L,S
Neoptics: S
Rayner Intraocular Lenses, Ltd.: C,L,S
Schwind eye-tech-solutions: C,L,S
David Huang MD PhD
AMO/Visx, Inc.: S
195
George D Kymionis MD PhD
None
Michael A Lawless MD
3D Vision Systems: C,O
AcuFocus, Inc.: C,O
Bausch + Lomb Surgical: C,P
BioSyntrx: C,O
Calhoun Vision, Inc.: C,O
Clarity Ophthalmics: C
Clear Sight: C,O
CoDa Therapeutics: C,O
Confluence Acquisition Partners I, Inc.:
O
Curveright, LLC: C
EBV Partners: C,O
EGG Basket Ventures: C,O
Encore: C,O
Evision: C,O
Eyemaginations: C,O
Foresight Venture Fund: C,O
Fziomed: C,O
Glaukos Corp.: C,O
Healthcare Transaction Services : O
Heaven Fund: O
High Performance Optics: C,O
Hoya Surgical Optics: C
Improve Your Vision: C,O
LensAR, Inc.: C,O
LenSX: C
Life Guard Health: C,O
Lumineyes, Inc.: C
Minnesota Eye Consultants: C,O
NuLens, Ltd.: C,O
Ocular Optics: C,O
Ocular Surgery News: C
Omega Eye Health: C,O
Omeros Corp.: C
Pixel Optics: C,O
Qwest: C,O,P
Refractec, Inc.: C,O
Revision Optics: O
SRxA: C
196
Parag A Majmudar MD
Allergan, Inc.: C
Ista Pharmacuticals: C,S
Mobius Therapeutics: C
Tear Science: C,S
Carl Zeiss Meditec: L,S
UK Network Medical: P
None
LenSx Lasers, Inc.: C
Alejandro Navas MD
None
None
Robert K Maloney MD
Marcelo V Netto MD
AcuFocus, Inc.: O
Calhoun Vision, Inc.: C,L,O
Presbia Corp.: C
Stroma Medical Corp.: O
Allergan: C
Allergan: C,L
Bausch + Lomb: C,L
Merck & Co., Inc.: C,L
Edward E Manche MD
Best Doctors, Inc.: C
Guidepoint: C
Ophthonix, Inc.: O
Seros Medical, LLC: O
Stephanie Jones Marioneaux MD
None
John Marshall PhD
Avedro: C,L,O
Ellex: L,O,P
Nexisvision: C,O
OPKO: C,P
Schwind eye-tech-solutions: L
Samuel Masket MD
Bausch + Lomb Surgical: L
Haag-Streit: C
Ocular Theraputix: C,O
PowerVision: C
Zeiss: L
Allergan, Inc.: C
Bausch + Lomb Pharma: C
Essilor: C
Focus Laboratories: C
Inspire Pharmaceuticals, Inc.: C
NexisVision: C
Ocularis Pharma: C
Optical Express: C
Pfizer, Inc.: C
Santen, Inc.: C
Zoltan Nagy MD
Louis D Skip Nichamin MD
3D Vision Systems: C,O
Allergan, Inc.: C
Eyeonics, Inc.: C,O
Foresight Biotherapeutics: C
Glaukos Corp.: C
Harvest Precision Components: O
iScience: C,O
LensAR: C,O
PowerVision: C,O
RevitalVision, LLC: C,O
SensoMotoric Instruments: C
WaveTec Vision System: C,O
Thomas A Oetting MD
None
Robert H Osher MD
Beaver-Visitec International, Inc.: C
Clarity: C
Haag-Streit: C
SMI: C
Video Journal Cataract & Refract Surg:
O
Ioannis G Pallikaris MD
Presby Corp.: C
Matteo Piovella MD
Aaren Scientific: L
Beaver-Visitec International, Inc.: C
Ocular Therapeutic: L
Soleko: L
Louis E Probst MD
TLC Vision: C
Arturo J Ramirez-Miranda MD
None
None
Dan Z Reinstein MD
Arcscan, Inc.; Morrison, Colorado: O,P
Olivier Richoz MD
None
Robert P Rivera MD
AcuFocus, Inc.: C
Endo Optiks, Inc.: L
Escalon Medical Corp: L
Staar Surgical: C,L,O
None
Diana F Rodriguez-Matilde MD
None
Emanuel S Rosen MD
Neoptics AG: C
Kenneth J Rosenthal MD FACS
Inspire Pharmaceuticals, Inc.: C
Johnson & Johnson Consumer &
Personal Products Worldwide: C
Microsurgical Technologies: C
Ophtec, BV: C,L,S
None
Allergan: C
Optical Express: C
Barry S Seibel MD
Bausch + Lomb: P
Calhoun Vision, Inc.: C,O
Neuroptics, Inc.: C
OptiMedica: C,O
Rhein Medical: P
Allergan: L
NuLens: C
Topcon Medical Systems: C
VisionCare Ophthalmic Technologies: C
Nidek, Inc.: C
Oculus, Inc.: C
Theo Seiler MD PhD
IROC, Inc.: O
WaveLight AG: C,L
Stephen G Slade MD FACS
AMO: C,L
ForeSight Labs: C
LenSx: C,O
RVO: C
Technolas: C
Michael E Snyder MD
Dr. Schmidt Intraocularlinsen: C
Haag Streit: L
Felipe A Soria MD
Gustavo E Tamayo MD
Abbott Medical Optics: C,L,O,P
Avedro: L
Cellular Bioengineering: C
Presbia Corp.: C
Vance Michael Thompson MD
Avedro: C
Bausch + Lomb: C
Euclid Systems: C
Forsight: C
Wavetec: C
None
Leopoldo Spadea MD
AcuFocus, Inc.: C
Zimmer: C
None
Jason E Stahl MD
None
Walter J Stark MD
VueCare Media: O
Roger F Steinert MD
Abbott Medical Optics: C,S
OptiMedica: C
ReVision Optics: C
Rhein Medical, Inc.: P
Pavel Stodulka MD PhD
Bausch + Lomb: L
TPV: L
Karl G Stonecipher MD
Alcon: C,L,S
Allergan: C,L,S
Bausch + Lomb: C,L
Endure Medical: L
LaserACE: C
Nexis: C,S
Nidek: C,L,S
Oasis Medical, Inc.: C,L
Refocus Group, Inc.: C,S
Staar Surgical: L
TLC Laser Eye Centers: E
Dan B Tran MD
ReVision Optics Inc.: C,O
WaveTec Vision Systems, Inc.: C,O
AcuFocus, Inc.: C
Optical Express: C
Staar Surgical: C
R Bruce Wallace MD
Allergan, Inc.: C
LensAR: C
George O Waring III MD FACS
A.R.C. Laser Corp.: C
Abbott Medical Optics: O
AcuFocus, Inc.: O
AskLasikDocs.com: O
Nidek, Inc.: C
Accelerated Vision: C
Focal Point, Asia: C
Gerson Lehrman Group: C
RevitalVision, LLC: C,L,O
Topcon Medical Systems: C,L
Steven E Wilson MD
Allergan, Inc.: C,L
Helen K Wu MD
Aton Pharmaceuticals: C
Bausch + Lomb: S
CXLUSA: C
EyeGate: C
Inspire Pharmaceuticals, Inc.: C,L,S
Ista Pharmacuticals: S
LensAR: C
QLT Phototherapeutics, Inc.: C,S
Rapid Pathogen Screenings: S
Tear Science: C
Iop, Inc.: L
Staar Surgical: L
Harvey S Uy MD
Roberto Zaldivar MD
LensAR: L
Staar Surgical: C
Tracey Technologies: C
Pravin Vaddavalli MD
Allergan: L
Jan A Venter MD
None
197
Sonia H Yoo MD
Allergan, Inc.: S
Genentech: S
Optimedica: C
SLACK, Incorporated: L
Transcend: C
198 Subspecialty
2012
Day | Refractive Surgery
198
Presenter Index
Abdou, Ahmed Abd El-Twab 78
Agarwal*, Amar 114
Ahmed*, Iqbal K 112
Alio*, Jorge L 56, 70
Alpins*, Noel A 94
Ang*, Robert Edward T 79
Auffarth*, Gerd U 141
Berdahl*, John P 157
Binder*, Perry S 48
Bower, Tenley N 56
Budo*, Camille J R 104
Carones*, Francesco 75, 77
Chang*, Daniel H 138
Chang*, David F 115
Chang*, John So-Min 19
Chayet*, Arturo S 123
Chen, Xiangjun 86
Cionni*, Robert J 134
Culbertson*, William W 133
Davis*, Elizabeth A 80
Devgan*, Uday 105
Dick*, Burkhard 74, 77
Donnenfeld*, Eric D 5, 142
Dougherty*, Paul J 95
Duffey, Richard J 128
Durrie*, Daniel S 58, 79
Gatinel*, Damien 10
Goldman*, David A 155
Grabner*, Gunther 88
Guell*, Jose L 81
Hafezi*, Farhad 126
Hannush, Sadeer B 103
Harvey*, Thomas M 158
Henderson*, Bonnie A 106
Hjortdal*, Jesper 21, 96
Holladay*, Jack T 135
Holland*, Simon P 56
Holzer*, Mike P 60
Hovanesian*, John A 99
Huang*, David 55
Ibrahim*, Osama I 9
Jackson*, W. Bruce 61
Joo, Choun-ki 57
Kanellopoulos*, A John 27
Katsanevaki, Vikentia 93
Khandelwal, Sumitra S 55
Kilic, Aylin 152
Kim*, Terry 108
Knorz*, Michael C 65, 79, 131
Koch*, Douglas D 94
Kohnen*, Thomas 91, 119
Krueger*, Ronald R 18
Lawless*, Michael A 129
Lindstrom*, Richard L 16
Majmudar*, Parag A 14
Males, John 24
Manche*, Edward E 97
Marioneaux, Stephanie Jones 52
Marshall*, John 47
Masket*, Samuel 117
McDonald*, Marguerite B 121
Mehta*, Jodhbir S 159
Nagy*, Zoltan 140
Navas, Alejandro 124
Netto*, Marcelo V 148
Nichamin*, Louis D Skip 98
Oetting, Thomas A 110
Osher*, Robert H 116
Pallikaris*, Ioannis G 92, 127
Probst*, Louis E 15
Ramirez-Miranda, Arturo J 96
Rapuano*, Christopher J 3
Reeves*, Sherman W 150
Reinstein*, Dan Z 7, 96
Richoz, Olivier 54
Rocha, Karolinne M 95
Rodriguez-Matilde, Diana F 95
Sachdev*, Mahipal S 54
Santhiago, Marcony R 121
Schallhorn*, Steven C 57, 78
Seibel*, Barry S 137
Seiler*, Theo 26
Slade*, Stephen G 146
Soria, Felipe A 57
Spadea, Leopoldo 23
Stark*, Walter J 100
Steinert*, Roger F 113
Stodulka*, Pavel 77
Stulting*, R Doyle 1
Tamayo*, Gustavo E 12
Tomita*, Minoru 67
Tran*, Dan B 78
Trattler*, William B 2
Uy*, Harvey S 78
Vaddavalli*, Pravin 17
Venter, Jan A 55, 79
Vinciguerra*, Paolo 44, 94
Vukich*, John Allan 66
Wallace*, R Bruce 107
Waring IV*, George O 147
Wilson*, Steven E 54
Yoo*, Sonia H 20
D E A D L I N E
:
A U G U S T
3 1 ,
2 0 1 3
Application for ISRS Membership
International Society of Refractive Surgery
Applications must be received by August 31, 2013 to qualify for the discount
for the Refractive Surgery Subspecialty Day Meeting.
A Partner of the American Academy of Ophthalmology
First Name
Medical Degree (i.e., MD, MBBS, etc.)
Family Name
Mailing / Postal Address
Home
Office
(Please check one)
City
State/Province
Postal Code
Country
Office Phone
Fax
Website
E-mail
Medical Training (Medical School)
Completion Date (Mo/Yr)
(Required)
(Required)
Ophthalmology Training (Name of School or Program)
(Required)
City
State/Country (if outside U.S.)
Beginning Date (Mo/Yr)
Completion Date (Mo/Yr)
(Required)
(Required)
AAO Member? (If so, please provide Academy ID #)
M E M B E R S H I P
L E V E L S
Applicants can pay their application fee to join this year, as well
as their membership dues for the following year.
U.S. and International Members
1 year $210 USD
P A Y M E N T
American Express
JCB
MasterCard
Visa
Discover
Check or Money Order Enclosed
For wire transfer information, please contact Member Services
2 years $405 USD
The tiered dues rates are based strictly on the completion dates
of your training (residency or fellowship).
Card Number
Exp Date
1st Year in Practice
1 year $145 USD
2 years $285 USD
2nd Year in Practice
1 year $145 USD
2 years $285 USD
3rd Year in Practice
1 year $165 USD
2 years $320 USD
Name on Card
Signature
Cardholder’s Address:
Associate Members
Non ophthalmologists (MD, DO, DVM, or PhD) working in
the field of ophthalmology or engaged in full-time
ophthalmology research are eligible to apply for this category.
1 year $210 USD
City
2 years $405 USD
Members in Training
No cost
(includes online Journal only)
(Application must be accompanied by a letter of verification from
Professor/Program Chair – begin and end dates must be included
in letter.)
Journal of Refractive Surgery Subscription (One Year) $95 USD
Total Amount Due:
$
USD
State/Province
Postal Code
Country
Please return your completed application to:
American Academy of Ophthalmology Member Services
Dept. 34048
P.O. Box 39000
San Francisco, CA 94139 USA
Tel:
+1.415.561.8581 or toll-free (U.S. Only) 866.561.8558 ext. 581
Fax:
+1.415.561.8575
E-mail: [email protected]
Do not write in this space, for accounting only:
Payment Received
Date
Lockbox Batch # (if applicable)
Amount
By
International Society of Refractive Surgery
A Partner of the American Academy of Ophthalmology
Join ISRS
www.isrs.org
Become a member of the International Society of Refractive Surgery (ISRS), a partner of the American
Academy of Ophthalmology. ISRS is the leading organization for refractive surgeons and keeps you
up to date on the latest clinical and research developments in refractive, cornea, cataract and lens-base d
surgery. Members are connected to the world’s leading refractive surgeons from over 80 countries
through its innovative meetings, publications and online educational tools.
Membership acceptance is subject to review and approval by the ISRS Executive Committee.
Benefits of Membership
• Subscription to the Journal of Refractive Surgery, the
official publication of ISRS. The Journal is a monthly forum
for original research, review and evaluation of refractive,
cataract, cornea and lens-based surgical procedures.
(Online subscription for Members in Training)
• Access to the online ISRS Multimedia Library providing
refractive, cataract and cornea videos, presentations and
conversations shared by leading surgeons from around the
world
• Complimentary online listing for your practice in Find a
Refractive Surgeon, a searchable online directory complete
with full contact information for practicing members
worldwide
• Access to the members only content on the ISRS website,
www.isrs.org, which includes the latest trends, news,
presentations and articles on refractive and cataract
surgery to further your knowledge and education
• Complimentary membership certificate
• Access to the ISRS Online Community, a place to exchange
clinical information, comment on the most recent advances
and theories in refractive surgery and receive advice from
colleagues worldwide
• Reduced registration fee for the 2013 Refractive Surgery
Subspecialty Day, the ISRS Annual Meeting. This
innovative meeting assembles international leaders in
refractive surgery, providing a forum for exchange of the
latest information in the field.
• Access to refractive and cataract information on the
Academy’s Ophthalmic News and Education (ONE®)
Network, an online resource that provides access to
clinically relevant content, news and tools from a variety
of trusted sources
• Monthly clinical e-newsletter, Refractive Surgery Outlook,
featuring expert opinion on the latest advances, highlights
from peer-reviewed clinical journals, a calendar of events
and ISRS information
• ISRS supports refractive surgery educational events
around the world through international meetings with
other ophthalmic societies by hosting a course or
symposium.
• Members of ISRS, who are not already members of the
American Academy of Ophthalmology, receive a $100
discount on the Academy’s application fee. For more
information and an application, go to the Academy
website at www.aao.org or contact Member Services at
[email protected].
How to Join
Please complete the application on the reverse side or join
online at www.isrs.org.
If you have any questions or would like additional
information on any of these programs and services, please
e-mail ISRS at [email protected] or call us at
+1.415.561.8581 or toll free (U.S. only) 866.561.8558 ext. 581.

Refractive Surgery Subspecialty Day Syllabus (PDF 6MB)

Transcription

Similar documents

972-258-6400 | TYLOCK.COM

HARTFORD`S FINEST

Part 1d

hartford`s finest - Proactive Resources

LASIK: Basic steps for great results ESCRS 2011

Abdominal Sacrocolpopexy with possible removal of ovaries

Laser Engraving - Source International

PE041 Tonsil and Adenoid Surgery

Heritage Surgery Center

May 12, 2013