Effective Myopia Control in Clinical Practice…2014 Disclosures

8/20/2014
Effective Myopia Control in
Clinical Practice…2014
Myopia Control in Children
“Is there anything that can be done to
control my child’s increasing myopia???
Disclosures
Patrick Caroline
FAAO
Consultant for
Contamac UK
Prevalence of Myopia and High Myopia
in 5,060 Chinese University Students in
Shanghai
Jing Sun, Jibo Zhou, Peiquan Zhao et.al.
Investigative Ophthalmology November 2012
•
•
•
•
Increased Prevalence of Myopia in the
US Between 1971-1972 and 1999 -2004
Susan Vitale PhD, Robert Sperduto MD, Frederick Ferris MD
Archives of Ophthalmology Vol. 127 No. 12 December 2009
Ages 12 -54
1971 1972
1971-1972
25.0%
Myopic
1999 2004
1999-2004
41.6%
Myopic
Eddie Chow
OD
Private Practice
Toronto Canada
-4 12 D
Mean spherical equivalent refraction -4.12
D.
95.5 % were myopic
19.5 % were highly myopic (> -6.00 D.)
Only 3.3 % were emmetropic
For Centuries Scientists and
Clinicians have Debated the
Question of Whether Myopia is:
• Genetic, (Nature)
- Ethnicity
- Family inheritance
• Environment, (Nurture)
- Molded by visual experience.
In 30 years a 17% increase in myopia
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European Descent
1. Orinda Longitudinal Study of Myopia
2. Sydney Myopia Study
Asian Descent
3. Singapore Study on Myopia
Our
Kid’s
Today
Possible Mechanisms
1. Less accommodative
demands in outdoor
environments.
Children who
spend more time
outdoors are
less likely to
become myopic.
Myopia or hyperopia can be induced in
chicks and reversed by manipulation of
the chromaticity of ambient light
WS Foulds, VA Barathi, CD Luu
Singapore Eye Research, IOVS January 2014
2. Pupil constriction in brighter
g resulting
g in greater
g
depth
light
of focus.
• Baby chicks were raised in red light (90% red and 10%
yellow/green) and in blue light (85% blue 15% green).
3. Direct light exposure may
releases retinal transmitters
Dopamine
Vitamin D
which may inhibit eye growth.
• Red light induced -2.83 D. +- 0.25 D.
• Blue light induced +4.55 D. +- 0.21 D.
Blue
Green and Red
• Exposure time was 12 hour on-off cycle for 28 days.
• The refractive changes were axial, confirmed by ultrasound
biometry.
• The induced myopia was reversed to hyperopia with blue light
exposure (+2.50 D.) and the hyperopia was reversed to myopia with
red light exposure (-1.23 D.)
Study Conclusions
The results suggest that the protective effects of
outdoor light against myopia in children are due to
exposure to the higher light levels in outdoor
environments approx 50,000 lux
This raises the possibility that substantial
th
therapeutic
ti b
benefits
fit could
ld potentially
t ti ll be
b achieved
hi
d by
b
manipulating indoor lighting levels that are usually
approx. 250 lux
John Ott 1909 – 2000 Landmark work in
the 1950’s with time lapsed photography
Father of Full Spectrum Lighting
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Myopia Control…
What is Meaningful Myopia Control?
The Search for the Holy Grail
A child at age 7 is diagnosed with -1.00 D. which
progresses -0.75 D. per year for 8 years.
• Bifocal Lenses
Relaxation of accommodation
• 0.75 D. Undercorrection
Relaxation of accommodation
• Rigid
Ri id Contact
C t t Lenses
L
Improving retinal imagery ???
• Pharmacologic Intervention
Target specific anatomic
structures of the eye
• Optical Intervention
Peripheral refractive error
Predicted Reduction of High Myopia for
Various Degreess of Myopia Control.
Noel A. Brennan OD PhD.
Contact Lens and Anterior Eye BCLA Abstracts 2012
High myopia > -5.00 D. is associated with increased risk
of: choroidal neovascularization, glaucoma, cataract and
retinal detachment.
Proportion of people who would avoid becoming high
myopes with varying degrees of successful myopia
control.
Reducing the rate of
myopia progression
33%
50%
Reduction in the
frequency of high myopia
73%
90%
The Optics of Myopia Control
If Myopia Progression
Is Slowed By
Final Myopia
Would Be
0%
-7.00 D.
50%
-3.62 D.
100%
-1.00 D.
Most eye care practitioner consider a 50%
reduction in myopia a “Myopia Control” effect
Walline 2012
Myopia Control…
The Search for the Holy Grail
• Bifocal Lenses
Relaxation of accommodation
• 0.75 D. Undercorrection
Relaxation of accommodation
• Rigid
Ri id Contact
C t t Lenses
L
Improving retinal imagery ???
• Pharmacologic Intervention
Target specific anatomic
structures of the eye
• Optical Intervention OK & MF SCL’s
Peripheral Optics
+18
-19
-7
+81
+50
What Regulates Eye Growth???
1. Emmetropization Studies
2. Form Deprivation Myopia
Studies
3 Lens Compensation
3.
Studies
4. Reduction Experiments
5. Local Retinal Mechanism
Studies
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What Regulates Eye Growth???
• In all species, (including
humans) the two eyes
typically grow in a highly
coordinated manner
towards the ideal optical
p
state, a process called
“Emmetropization”
Fundamental Across All Species
Rodents
Primates
Cats
Rabbits
Marsupials
Birds
Fish
• The process is regulated
by visual feedback.
Survival
of the
Species
Emmetropization in Infants
Earl Smith
Chronic Image Degradation Causes Myopia
Wiesel & Raviola 1977
Chronic Image Degradation Causes Myopia
Wiesel & Raviola 1977
Monocularly lid-sutured Monkey
Conditions that prevent the
formation of a clear retinal
image cause the eye to grow
abnormally long and become
myopic
myopic.
Monocularly lid-sutured Monkey
Form-Deprivation
Myopia
Earl Smith
The potential for a clear
retinal image is essential for
normal refractive
development.
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Form Deprivation Myopia
If an eye that has fromdeprivation myopia is
corrected with spectacle
lenses no recovery takes
place.
Conclusions, Smith et.al.
#1
A functioning fovea is not essential for
normal axial development.
However, if the eye is
allowed unrestricted
(uncorrected) vision, the
eye will recover through
a:
visual feedback
mechanism.
An Intact Fovea Is Not Essential for
Normal Axial Eye Growth
Conclusions Smith et.al.
#2
An intact periphery is essential for
normal axial development.
Smith et. al. Univ of Houston
Hemiretinal Form Deprivation: Evidence for
Local Control of Eye Growth and Refractive
Development in Infant Monkeys
Earl L. Smith et al.
Investigative Ophthalmology & Visual Sciences
Vol50 No. 11 November 2009
Peripheral retinal receptors take in visual
information and provide the signal for the eye
to grow (or to stop growing) in a
regionally selective fashion.
Study
Eye
Study
Eye
Control
Eye
Control
Eye
The vision-dependent mechanisms that regulate eye
growth are located IN THE EYE.
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Retinal Area and Neurons at the
Fovea vs 30 deg.
Peripheral Hyperopia
Thus, if there is spatial summation of signals from
the myopic center and the hyperopic periphery, the
peripheral signal will dominate the eye growth.
Myopia Control Studies with Ortho-K
Epithelium = 50 microns
Average +49%
Rule #1, the Optics of OK
Rule #1
The foval treatment zone in OK is
approximately 1.5 to 2.5 mm in diameter.
6.0 mm
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Post -4.75 LASIK
-4.75 D
-4.75 D.
5.0 mm Pupil
Post OK -5.00 D.
-5.00 D
5.0 mm Pupil
LASIK
5.0 mm Pupil
Rule #2, the Optics of OK
The amount of peripheral plus power at 5.0 mm,
is equal to the central minus power corrected.
-4.75 D..
Ortho-K
5.0 mm Pupil
-5.00 D.
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Rule #2
-2.75 D. Correction
5.0 mm Pupil
+2 50
+2.50.
2 75 D.
-2.75
5.0 mm Pupil
+3 00
+3.00
-5.75 D. Correction
+2 50
+2.50.
2 75 D.
-2.75
-8.75 D. Correction
+8.62
+6.00
6 00
-5.75 D..
+3 00
+3.00
-8.75 D. +8.75
+6.25
6 25
Pupil Size and Myopia Control How Hyperopic is the Peripheral
Retina at 30 Degrees ???
+1.00 D., +2.00 D., +3.00 D. or +4.00 D.
+6.00 D. @ 6.0 mm.
+3.00 D. @ 4.0 mm
-5.00 D.
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Do Peripheral Refraction and Aberration
Profiles Vary with the Type of Myopia?
The Journal of Optometry 2009
•
•
•
Ravi Bakaraju, Klaus Ehrmann, Eric Papas, Arthur Ho
Vision Cooperative Research Center, Sydney Australia
-2
2.00
00 D
D.
Average
difference
between the
foval refraction
and that
30 degrees away
was between
Traditional 5 Curve OK Lens Design N = 165
Aspheric 6 Curve OK Lens Design N = 129
Historical Control CLEERE Study 2007
Traditional 5 Curve Design
-4
4.00
00 D
D.
-6.00 D.
Chow 5 Year OK Axial Length Study
Aspheric 6 Curve OK Design
+1.00 D.
and
+1.50 D.
Five Year, CLEERE Study, Axial Length Data
Refractive Errors Age 9 to 14
Traditional 4-5 Curve Design
76 um
5um
Chow Study 5 Year Axial Length Data
Image
Shell
Traditional 5 Curve OK Lens Design N = 165
Five Year Axial Length C
Change From
Baseline (mm
m)
1.8
Myopic Asian Children
1.6
+1.00 D
1.4
Other Myopic Children
1.2
-1.00 D.
1.0
.8
.6
+1.00 D.
.4
.2
.0
-1
-2
-3
-4
-5
Baseline Spherical Equivalent (D Rounded)
-6+
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Myopia Control 6 Curve Design
+5.00 D
-5.00 D.
+5.00 D.
106 um
10 um
Chow Study 5 Year Axial Length Data
Change From
Five Year Axial Length C
m)
Baseline (mm
1.6
1.4
Myopic Children Asian and Non-Asian Children
1.2
1.0
.8
Asian Emmetropic Children
.6
Non-Asian Emmertopic Children
.4
.2
.0
1
2
3
4
5
6
Baseline Spherical Equivalent (D Rounded)
Kakita et al 2011
1.8
Five Year Axial Length Ch
hange From Baseline
(mm)
Aspheric 6 Curve OK Lens Design N = 129
1.6
Lens Design and Myopia Control
1.4
1.2
1.0
.8
.6
.4
.2
.0
-1
-2
-3
-4
-5
-6+
Baseline Spherical Equivalent (D Rounded)
Blur Circle and Myopia Control
The size of the blur circle increases with the distance
of the image from the retina.
Lower the Myopia
Correction, Greater
Axial Eye Growth
Higher
g
the Myopia
y p
Correction, Less
Axial Eye Growth
Therefore, if there is spatial summation of signals from
the myopic center and the hyperopic periphery, the
peripheral signal will dominate the eye growth.
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Graded Competing Regional Myopic and
Hyperopic Defocus Produces Summated
Emmetropization Set Points in Chicks
Dennis Y. Tse and Chi-ho To IOVS 2011
Center for Myopia Research, School of Optometry, Hong Kong
Polytechnic University
Investigated
g
the axial
response of the eye
when a specific
proportion of the retina
was exposed to myopic
defocus while the
remainder was exposed
to (competing)
hyperopic defocus.
“As the proportion of retinal area receiving myopic
defocus increased…the degree of myopic eye
growth will be reduced”.
RESULTS:
Correction
-8.90 D
-2.40 D
+1.60 D
+5.90 D
+7 60 D
+7.60
+10.40 D
Ratio
0/100
25/75
33/67
40/60
50/50
100/0
VCD
+592
+230
-105
-253
447
-447
-515
Myopic Defocus
Hyperopic Defocus
Effects of Traditional Spectacle
Lenses on Peripheral Refraction
Tabernero et.al Vision Research (49.) 2009
Traditional
Spectacle
Lenses
If lenses were being developed to
INCREASE myopia progression...would we
ever prescribe those lenses?
Center Distance Multifocal Soft Lens Designs
Cooper Vision
Cooper Vision
Vistakon
Acuvue Oasys for Presbyopia
Design:
CD (Center Distance) DK 103
Base Curve:
8.4 mm
Powers:
+6.00 to -9.00 D
Diameter:
14.3 mm
Adds:
+0.75 to +2.50 in 0.50 D. steps
The design,
design incorporates 5 concentric rings with
alternating distance and near powers zones.
Pete
Kollbaum
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Center Distance Multifocal Soft Lens Designs
Cooper Vision
Cooper Vision
Vistakon
John Phillips OD PhD New Zealand
MiSight
Manufactured by Cooper Vision
Distributed in Hong Kong, China
Pete
Kollbaum
Walline 2011
Dual Focus Design
Cooper Vision Multifocal “D” Lens
•
•
•
•
Children 8-11 (-0.75 to -4.00 D.)
Historic controls (ACHIEVE Study)
Proclear Multifocal “D” lens +2.00 D. add
2 year results
49% myopia reduction
40% reduction in axial length
D NDN
Center Distance Multifocal Lens Design
Cooper Vision
Cooper Vision
Cooper Vision PROCLEAR MF XR
Vistakon
Design:
Base Curve:
Powers:
Diameter:
Adds:
CD (Center Distance) 6 pack
8.7 and 8.4 mm
+20.00 to -20.00 D
14.4 mm
+1.00 to +4.00 in 0.50 D. steps
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Distance Power -3.00 D. +3.00 Add
43.75
43.75
40.75
Patient History and Myopia Control
When??? Ages 7 to 12
• Age of the patient
– early (genetic) faster progression more sever
– late onset (acquired) slower progression less sever
• Amount of myopia example 7 y/o
– +1.00, Plano, -1.00
• Family
y history
y
– mom and dad
• Environment history
– Outdoor exposure per day
• Contact lenses
– Patient and parent physically & psychologically
• Practitioner
– Training and expertise with the various modalities
Today!!!
Myopia Control
Peripheral Defocus Theory
“Is there anything that can be done to
control my child’s increasing myopia???
Image
Shell
Image
Shell
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Myopia Control
The Future
14