and contact lenses - Eyeness, Kontaktlinsenstudio

Presbyopia
and contact lenses
Michael Wyss
dipl. Augenoptiker FAAO
[email protected]
kontaktlinsenstudio baertschi, Bern, Switzerland
Modul 3
•
Contact Lenses for Presbyopia
– Monovision / Simultaneous / Alternating
– Rigid & Soft Aspheric Multifocals
– Rigid & Soft Concentric Multifocals
– Soft Diffractive Multifocals
– Rigid & Soft Segmented Bifocals
Duration 5 hours
Goals
• Specification of the presbyopic eye
• Understand and differentiate the various
correction principals for presbyopia
– Monovision / Aplanate and Diffractive Design
– Translating Design / Simultaneous Design
• Know the fitting pearls of every Method
• Identify fitting problems and know the
specific problem solving
Why this Topic?
• The population of South Africa (age over
49) will double in the next 20 years
• The potential for contact lenses in that
market segment is enormous
– Nearly half of the population would like to try
contacts if they would have the opportunity
(Germany 2007)
Demographics
Economy
• Net income is the highest used for the
correction of presbyopia
• Fitting contact lenses in this area isn’t
easy and emphasize you as a specialist in
health care
Economy
• The mature population is the most loyal to
your practice
• If you fix a mature Patients problem, often
the entire family will be send to “THE”
specialist
Todays Presbyopic are . . .
• Health-conscious and financially secure
• Physically and socially active
– Experienced contact lens wearers
• Interested in maintaining youthful
appearance
Blind-Date
• Get in contact with your patients, you have
to invest in those „relationships“
• A good patient history goes a long way
and needs a complete anamnese
Patients needs and wishes
• Listen very carefully and active
• Every single „little something“ or habit is
important
• Ask open questions
• Give your patient and yourself enough
time
Patients needs and wishes
Your expectations
• Living a realistic optimism
• Show all compromises of all forms of
vision correction
• To cover 80% of the patients needs, leads
in 100% success
Additional objective Findings
• Lid, position and consistent
• Pupil diameter
• Depth of the anterior chamber
• Tear layer - quality and quantity
Presbyopic Eye
•
•
•
•
•
•
•
Need less oxygen
Less corneal sensitivity
Increased positive spherical aberrations
May see poorly in low light
Increased light scatter (glare)
Smaller pupil size
Increased dry eye symptoms
Monovision
Monovision
• Figure out the dominant eye
– Different possible technics: “hole in a hand"
and the "plus blur tolerance”
• No forced choice method
– Let Patient point with a finger on a small
target
– The eye which stays aligned with the target is
the dominant one
Monovision Assessment
• Near target with a plus trial lens in front of
the non-dominant eye
• Target for distance with the same lens
situation
• If the vision’s not comfortable in one of
these situations, consider other options
Modifide Monovision
• Necessary if intermediate distance is
missing
• The dominant eye still need to be
corrected as good as possible for distance
• Adjust a bifocal solution in the nondominant eye
Aplanate / Diffractive Systems
Aplanate Systems
• Using aspheric optic designs, leading in
the correction of the optical aberrations,
achieve a better depth perception
• Useful up to max. Addition of + 1.5dpt
• Not centered or dehydrated contact lenses
will extremely decrease vision acuity
Diffractive Systems
Diffractive Systems
• Using diffractive optic designs for splitting
light into two or more diffractive orders to
different focal distances or ranges
– Useful up to max. Addition of +1.5dpt
– Not centered or dehydrated contact lenses
will extremely decrease vision acuity
Simultaneous Systems
Simultaneous bifo. Systems
• Concentric rings of distance and near
correction (bifocal)
Bifocal, Simultaneous NC
© by Bach Optik
Bifocal, Simultaneous DC
© by Bach Optik
Simultaneous multi. Systems
• Concentric progressive / degressive
correction changes from center to the
periphery (aspheric / multifocal designs)
Multifocal, Simultaneous DC
© by Bach Optik
Multifocal, Simultaneous NC
© by Bach Optik
Advantages of simultaneous CL
• Distance and intermediate vision tasks
• Requires near vision in other than 270°
• Deep lower lid position / small lid opening
• Big pupil diameter / flat anterior chamber
Disadvantages of simultan. CL
• Decreased contrast sensitivity, especially
with uncorrected astigmatism
• Dehydration of Soft-CL decrease contrast
sensitivity additionally
• All designs are more or less pupil size
related
Simultaneous, bifocal Design
• Higher Addition than +1.75dpt
• No intermediate vision demands
• Minimal night vision demands
Simultaneous, multifocal Design
• Hyperopia
• High night vision demand
• Low Addition up to +1.75dpt
• Low / moderate astigmatism
Simultaneous CL fitting pearls
• Golden Rule: Assess vision binocularly
– Correct even little Astigmatism
• Use individual diagnostic lenses or flippers
to over-refract.
• Excellent lens centering needed
Simultaneous CL fitting pearls
• Chose the near optic zone smaller on the
dominant eye
– Small adjustments in optic zone diameters
lead in dramatic visual changes for your
patient
• Better contrast sensitivity achieved with
lower Addition on dominant eye
Simultaneous CL fitting pearls
• Soft-CL only available with very low DK’s
– except Purevision Multifocal™ and Contamac
Definitive™ Material
• In thick contacts (plus corrections),
contrast sensitivity can be decreased
– MMA/VP materials instead of GMA/HEMA
(Blank clarity)
Simultaneous CL fitting pearls
• Size of the optic zones
– 60% of pupil diameter = target
– Understand differences between near center
and distance center with the same size of
zone diameter
Simultaneous CL fitting pearls
2mm
2mm
Pupil
Pupil
40% distance
20% distance
Simultaneous CL fitting pearls
• Gas permeable contact lenses (GP)
– thin edge and big diameter (perilimbal /
miniscleral GP Designs)
– DK >100, makes Continuous Wear possible
(geriatric / pediatric solutions)
Translating Systems
Translating Systems
© by Bach Optik
Translating Systems
© by Bach Optik
Advantages of transl. Systems
• High contrast sensitivity demand
• High distance and near demand
• Moderate to high myopia and astigmatism
• Unrelated to pupil size and anterior
chamber depth
Disadvantages of translating CL
• Moderate vertical movement of CL
necessary
– And so, foreign-body sensation will be
increased
• Intermediate vision demands not included
Disadvantages of translating CL
• Near target only visible in down gaze
– As a consequence distance vision not
possible in down gaze
• Because of the amount of movement
needed, normally impossible for soft
contact lenses
Translating Design: fitting pearls
• Perfect fitted back surface (3+9 o’clock
staining) especially in cases with an
astigmatic cornea topography
• Don’t use a too big size of the vertical
diameter of CL
Advanced problem solving (GP)
• Rapid drop of CL after blink, achieved by
oval size of the CL in 90°
Advanced problem solving (GP)
• Highrider or slow translating of CL after
blinking
– Periphertoric backsurface Design
– Toric backsurface Design
Advanced problem solving (GP)
Advanced problem solving (GP)
• Off-center contact lens
Advanced problem solving (GP)
• Rotation of segment
– Off-set prism axis (not in 270°)
– Off-set segment axis
Advanced problem solving (GP)
Advanced problem solving (GP)
• Segment slides underneath the lower lid
– Truncation
Advanced problem solving (GP)
• Segment slides underneath the lower lid
– Shelf
Disposable contact lenses
• Near central, with degressive power
changes (Focus Progressiv™, Purevision
Multifocal™, etc)
Disposable contact lenses
• Distance central, multiple concentric rings
(Acuvue Bifokal™)
Disposable contact lenses
• Combination of distance and near central,
with degressive or progressive Design
(Proclear Multifokal™ System)
Disposable: Golden rule
• You need to know the advantages and
disadvantages of your used systems
• Play with the different available CLdesigns on the market
– DC / multifocal on dominant eye
– NC / bifocal on non-dominant eye
Disposable: Golden rule
• After all, still pay attention to the fitting
recommendations of the manufacturer
• As a reminder: DK mostly absolutely bad
(HEMA!)
– Exception Purevision Multifocal (Dk/t 120)
Disposable: Golden rule
• Excellent centering needed
• Assess vision binocularly, under normal
light condition, without phoropter
• Since 2008 Proclear Multifocal™ in
Astigmatic Design available
Questions drives you mad
• What System have the “Best” optics?
• Which Material is the most comfortable?
Translating Soft-CL (Triton™)
• Manufacturer Gelflex, Australia
Translating Soft-CL (Triton™)
• Horizontal Diameter 14.5 or 15.0
• Vertical Diameter 12.90 or 13.50
• Central radius with diameter 14.50:
flattest cornea radius plus 0.8mm
• All Parameters can be changed
individually
Translating Soft-CL (Triton™)
• Consistent, position, sensitivity and the
angle of the lower lid margin are important
• If the vision gets worse after putting the
Triton™ on the eye, the CL is to steep
fitted
• Pay attention on good translation in down
gaze
Translating Soft-CL (Triton™)
Transl. Soft (BYO Royal™)
• Translating Design from Procornea,
Netherlands
• Indication is given as by the Triton™, but
is distinguished by a more comfortable
Design in the area of the lower lid
Transl. Soft (BYO Royal™)
The Future is Now!
• Siliconhydrogel, individual contact lenses
in 3month or 6month replacement
schedule
– Defintive™ Material, Contamac
• Orthokeratology
– CRT Multifokal™ (Paragon)
– Nypon Mulftifokal™
The Future is Now!
• Translating-Simultaneous Design
– (Falco Kontaktlinsen BA, Switzerland)