Biomedical science, anterior segment diseases and advanced

Transcription

Biomedical science, anterior segment diseases and advanced
Biomedical science,
anterior segment diseases
and
advanced contact lenses
M i c h a e l W y s s & M i c h a e l Bärtschi
M.Sc.Optom. et M.Med.Educ., FAAO
kontaktlinsenstudio baertschi, Bern / Switzerland
Adjunct faculty New England College of Optometry, Boston/USA
Schedule
1st Day Saturday:
Modul 1
(5 lecture hours)
2nd Day Sunday :
Modul 2, A & B, 3
(5,5 lecture hours incl.
2 x 1,5 hours workshop)
3rd Day Monday :
Modul 3 & C, 4
(6 lecture hours incl.
1,5 hours workshop)
4th Day Tuesday:
Modul 4, 5, 6
(7,0 lecture hours)
5th Day Wednesday:
Modul 6, 7
(5,5 lecture hours)
incl. final discussion
5. Orthokeratology and Myopia
Control
•
Modern Orthokeratology lens design and history of OK
•
Orthokeratology theory and research, Myopia control
•
Patient selection and fitting
•
Results, complications and complication management
in OK
Duration 4 hours
6. Contact lenses for Infants and
Children's
•
List all ametropic conditions of babies, toddlers and children
•
Understand the different approach to serve babies and
toddlers
•
Differentiate the visual tests
•
Understand the specific visual needs of babies, toddlers
and children
•
Describe the fitting procedures of RGP lenses on children
•
Identify the need for multi focal RGP contact lenses
•
Get news ideas and perspectives
Duration 3 hours
A day in the eye hospital
University Eye Hospital Basel, Switzerland
A day in the eye hospital
Experience the extraordinary !
A day in the eye hospital
From babies to
old men
A day in the eye hospital
From beautiful
to ugly
A day in the eye hospital
Most of the time very vibrant !
Introduction
General statements of Optician, Optometrists and
Ophthalmologists (in Europe) :
- Children can‘t bear contact lenses !
- Children do loose their contact lenses constantly !
- On a growing eye you can’t fit a contact lens !
- As long as the child can’t pay for his lenses
himself, it is not allowed to wear contact lenses !
Target group 1
Approx. 20-40 % of the European School children are
ametropic.
Approx. 50 % of the European-Teenagers are ametropic.
100 % of all of them need a excellent optical and
social solution.
Source : MedLine/PubMed (Sweden, UK, Spain, USA)
About 1,44 Mio Children per year in Germany, Austria and Switzerland
Target groups
Astigmatism
Hypermetropia
Myopia
Anisometropia
Aphakia
Children and eye glasses
Children loves eye glasses ! (Hyperopia +8,0 dpt)
At least their parent believe and unfortunately some optometrists !
Children and eye glasses
Children loves contact lenses ! (Hyperopia +8,0 dpt)
This is what the children believes and their contact lens specialists !
Target group Aphakia
0,03 % of the new born do need cataract surgery during the
first five weeks of their live. (Intracapsular lens extraction)
0,01 % of the children do need Cataract surgery due to
systemic or traumatic reasons
100 % of all of them need a excellent optical
and social solution.
Source : MedLine/PubMed (Spain, Sweden, UK, USA)
About 29‘000 per year in US/Canada und Europe
Methods
Traditional optical aid :
- Eye glasses (SV, Bifocal, Multifocal)
- Contact lenses (SV)
- Contact lenses (SV) and reading glasses
- IOL and contact lenses or eye glasses
- Multifocal IOL (effective reading power/Add less than commercially
described)
- LASIK / LASEK ?
- Orthokeratologie ?
Methods
You have to see thru children's eyes to
fit contact lenses for children
Myopia (approx. -1,5 dpt)
Visual image
with myopia
Anisometropia (approx. -1,5 dpt)
Methods of investigation
Autorefraktometer
and –keratometer
(e.g. Retinamax)
Topography and Slit
lamp
Retinascope and
Ophthalmoscope
Methods of investigation
Dynamic close distance retinascopy (Mohindra)
Image is an Illustration : Correct would be monocular and in a dark room !
Methods of investigation
Preferential Looking Test (Babies from 2-3 months)
Methods of investigation
Preferential Looking Test
Visual evoked cortical potentials VECP
Methods of investigation
Teller Cards (A.Young 1997)
Babies from 2-3 months
Cardiff Cards (Infants of 1-3 years)
Methods of investigation
Lang-Stereo-Test (Infants of 1-3 years)
Glasmarbles or Sugar pearls (Infants of 1-3 years)
Methods of investigation
Lea Hyvärinen Test
Children from 3 years
Methods of investigation
Landolt rings und Snellen
signs from approx. 5 years
Numbers and letters from
approx. 6 - 8 years
Methods of investigation
Vision Contrast Test (VCT) und Functional Acuity Contrast Test (FACT)
(from approx. 6 - 8 jährig)
Methods of investigation
Ophthalmoscope as „Hand held magnifier with
illumination“ (up to 5x magnification)
Methods of investigation
Blue light LED Hand held magnifier with yellow filter
and 2,5 x Magnification
Methods of investigation
Blue light LED Hand held magnifier with yellow filter
and 2,5 x Magnification
Table of estimation
Age
CL radii
n.E.
1. Month
6.80 - 7.00 mm
0.0 – 0.3
6. Months
7.00 - 7.20 mm
0.0 – 0.3
1 Year
7.20 - 7.40 mm
0.3 – 0.4
2 Years
7.40 - 7.60 mm
0.3 – 0.4
3 Years
7.60 - 7.80 mm
0.3 – 0.4
5 Years
7.60 - 8.00 mm
0.4 – 0.5
8 Years
7.60 - 8.00 mm
0.4 – 0.6
TIP 1. Fit over all diameter OAD as large as
possible and as small as necessary.
2. Only use materials with high oxygen
permeability (Dk).
3. Fit periphery slightly tighter than for an adult.
(n.E. parallel or even – 0,1)
4. Choose large front optic zone according to
the juvenile pupil diameter. (> 7mm)
TIP Very often oval diameters e.g. 10.0 / 9.2 mm
Different colours for the right and the left contact lens.
e.g. Blue / Ice Blue
TIP Even Teenies do use make-up already excessive and wrong !
Aphakia with CL and Bi-focal glasses
Table of estimation (Aphakia)
Age
Power
CL radii
Add. reading
1. Month
+ 35 dpt
6.80 - 7.00 mm
+ 6.00 dpt
6. Months
+ 30 dpt
7.00 - 7.20 mm
+ 5.00 dpt
1 Year
+ 25 dpt
7.20 - 7.40 mm
+ 4.00 dpt
2 Years
+ 23 dpt
7.40 - 7.60 mm
+ 3.75 dpt
3 Years
+ 21 dpt
7.60 - 7.80 mm
+ 3.50 dpt
5 Years
+ 20 dpt
7.60 - 8.00 mm
+ 3.25 dpt
8 Years
+ 18.5 dpt
7.60 - 8.00 mm
+ 3.00 dpt Text
Table not valid in case of Microphthalmus or Megalocornea !
TIP 1. Fit over all diameter OAD as large as possible
and as small as necessary.
2. Only use materials with very high oxygen
permeability (Dk).
3. Fit periphery slightly tighter than for an adult.
(n.E. parallel or even – 0,1)
4. Choose large front optic zone according to the
juvenile pupil diameter. (> 7mm)
5. Only use light colours. (white or Ice Blue)
6. Add according the length of the arms !
TIP Jessica, 6 Jahre
Francesca 5 Jahre
TIP Jessica, 6 Jahre
Francesca
5 Jahre
Tri-focal
RGP on a eye
of a
2 years infant
Peri- (extra)limbal RGP on an eye
of a 14 years old teenager
Methode
Children are substantially limited due to the use of
sub-optimal optical aid:
- in their social environment
- in their Mobility
- in their personal development
Source : Roger L. Hyatt,MD : „Rehabilitation of children with Cataracts“ 1998
and Patient questionnaire (University Eye Hospital Basel Summer 2000)
Methode
Fitting of hyper permeable RGP single vision or multifocal contact lenses for the purpose of ametropia,
astigmatism and aphakia correction.
RGP contact lenses :
- Because of physiological reasons (Bo-XO, Optimum Extreme, Menicon Z)
- Because of the tremendous technical possibilities and quality
- Because optical or anatomical changes are easy to handle
- Because infants and children do tolerate RGP contact lenses well
(age depending approx. 80-99%)
Myopia
Single vision RGP
Aphakia with CL and Bi-focal glasses
Aphakia with CL and Bi-focal glasses
Multifocal RGP
Bi-, Multi- oder Trifocal
D
I
N
D
I
N
Retina
Simultaneous Systems are the preferred lenses for infants or children’s.
Multifocal RGP CL
RGP und Myopie Progression
Scientific studies are contradictory !
If any positive effect, only with RGP lenses and
only in the first year of use.
Is Ortho-Keratology the new „magic bullet“ ?
Image Ortho-K : KL-Studio Bärtschi
Image Modula M : D. Wegmann, Galifa
Results1
89.6 % of all babies and children, new fit with RGP
single vision contact lenses in the last 8 years,
successfully wear their lenses daily. (n=96)
- 8 children had to be refitted with Silicone-Hydrogel lenses after failed
with the RGP fit.
- 2 fittings had to discontinue due to refusal and non-compliance.
- Most of the children wear their lenses on extended wear mode with
cleaning intervals of 1 – 6 weeks
- 2 x Conjunctivitis bulbi and 1 x Conjunctivitis tarsi, 0 x Keratitis
Infants and children with CL
Infants and children with CL
Infants and children with CL
Lukas, 2 ½ Jahre
Results 2
All(*) of the 15 congenital cataract babies, who underwent cataract surgery
between 1992 and 2002 were refitted with multi-focal RGP lenses
between February 2000 and summer 2005, developed subjective and
objective quicker, are smarter and are much more integrated in their
social environment than before with their single vision contact lenses
and bifocal eye glasses. (n = 15)
(Questionnaire University Eye Hospital Basel, Switzerland)
(*) 1 Child got an Intraocular lens due to non-compliance after 1 year.
„My child is finally as normal as any other child her school class !“
Diskussion1
Not only tolerate children RGP contact
lenses well, babies can be fitted as young
as a few weeks of life and cause in
general less ocular problems than most
adults.
Diskussion2
Are Silicone-Hydrogels applicable for children ?
Definitely YES, as well as spheric or toric lenses !
-
Disposable as well as traditional lenses possible.
-
Important: To assure lens care and exchange rhythm.
-
Steep BC most useful (Acuvue Oasys 8,4, Acuvue Advance 8,3 or
Night & Day 8,4, Air Optix Individual).
-
After swimming always clean the lenses !
-
More often transient ocular problems than with RGP lenses
-
The children usually just forget that they are wearing contact lenses.
Please mind the many technical possibilities.
Well established Silicone-Hydrogels
Night & Day
Pure Vision
Acuvue
Advance
Air Optix
Lotrafilcon A
Balafilcon A
Galyfilcon A
Lotrafilcon B
Senofilcon A
35 %
Ionic
110
47 %
Non-ionic
85
33 %
Non-ionic
138
38 %
Non-ionic
147
Plasma oxidation
glassy silicate
“islands”
No surface
coating
hydroclear
25nm plasma
coating-continuous
hydrophilic surface
No surface
coating
hydroclear
Base Curve
24 %
Non-ionic
175
25nm plasma
coatingcontinuous
hydrophilic
surface
8.4 / 8.6
8.6
8.3 / 8.7
8.6
8.4 / 8.8
Diameter
13.8
14.0
14.0
14.2
14.0
Power
-10 to + 6
-12 to +6
-12 to + 8
-10 to + 6
Center thickness
(- 3.00D)
0.08
0.09
0.07
0.08
0.07
Visibility tint
UV blocking
visibility tint
Visibility tint
UV blocking
visibility tint
Material
Water Content
Dk/t
Surface
Treatment
Other
April 2008 (MiB)
Acuvue Oasys
-12 to + 8
Well established Silicone-Hydrogels
Biofinity
PureVision Toric
Acuvue
Advance f Astig
Comfilcon A
Balafilcon A
Galyfilcon A
Sifilcon A
Hygel
Dk/t
48 %
Non-ionic
160
35 %
Ionic
110
47 %
Non-ionic
86
32 %
Non-ionic
117
54 %
Non-ionic
53
Surface
Treatment
No surface
coating
Plasma oxidation
glassy silicate
“islands”
No surface
coating
hydroclear
25nm plasma
coating-continuous
hydrophilic surface
No surface
coating, lathing
Base Curve
8.6
8.6
8.5
7.4 - 9.2
All
Diameter
14.0
All
- 12 to + 8
14.5
-12 to + 8
13.2 / 14.0 / 14.8
Power
14.0
-9 to +6
-0.75 bis -2.25 cyl
-0.75 bis -2.25 cyl
-20 to + 20
All
Center thickness
(- 3.00D)
0.08
0.10
0.07
0.07
0.10
Visibility tint
UV blocking
visibility tint
Visibility tint
UV blocking,
clear/visibility tint
Material
Water Content
Other
April 2008 (MiB)
Visibility tint
Air Optix Custom Hygel sph & toric
Children are able to communicate
Melanie, 8 years old
Aphakic girl 7 – years old
Aphakic girl 7 – years old
Conclusion
Keep your
perspective,
stay cool and
never give up !
We wish you great success with contact
lenses for our most valuable patients !

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