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ÉTUDE DE L’ADDITION PÉRIPHÉRIQUE OPTIMALE DANS UNE LENTILLE MULTIFOCALE POUR CONTRÔLE DE MYOPIE

Simon-Pier Falardeau, Guillaume Landry-Proulx

Langis Michaud, Rémy Marcotte Collard, Patrick Simard

École d’optométrie Université de Montréal

ORTHO‐K: MYOPIA CONTROL IS NOT MYOPIA CORRECTION

Dr Langis Michaud O.D. M.Sc. FAAO (Dipl) FSLS FBCLA FEAOO

Professor

Dr Daniel Brazeau O.D. FAAO

Clinical Instructor

École d’optométrie Université de Montréal

Dr Michaud: Honorarium or reserach fund received

Bausch & Lomb

Cooper Vision

VIT- NAturalEyes

Synergeyes

Co-owner USPTO 62/590,388 Medical device for axial length and myopia management

Dr Brazeau: Nothing to disclose

Disclosure

EPIDEMIC MYOPIA ? REALLY ?

?

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According to Oxford dictionary epidemic means A widespread occurrence of an infectious disease in a community at a particular time.

Most likely not applicable to myopia…. BUT…. It means also …

1.1 A sudden, widespread occurrence of an undesirable phenomenon

- This is myopia

Is myopia epidemic ?

X 2 prevalencein 20 years…

sudden if referred to

human hx scaleAsia

Europe North

America

RetinaldetachmentGlaucoma

At riskcataract sx

How Bad is the Myopia Epidemic?

Doing nothing is doing something

Holden BA, Fricke TR, Wilson DA, et al. Global Prevalence of Myopia and High Myopia and Temporal Trends from 2000 through 2050.

Ophthalmology. 2016 May;123(5):1036-42. doi: 10.1016/j.ophtha.2016.01.006. Epub 2016 Feb 11. Review.

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How would you define myopia ?

1. Simple refractive error easily correctable

2.A significant risk factor for legal blindness

3.A loss of emmetropization process

Understanding myopia

Emmetropization• The bulk of emmetropization occurs in early

childhood and is largely complete by age 6.

• Therefore, refractive errors that exist at this age can be considered failures of emmetropization.

• The commonest refractive error at age 6 is hyperopia with both anisometropia and myopia being far less common at this age.

• Therefore if you have a myopic spherical equivalent in a child 6 and under, you have a very high likelihood and predictability factor that the child will be myopic in the future.

IOVS/IMI WHITE PAPERS

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Where does myopia come from ?

GENETICS

MYOPIA 

EPIGENETICS

30% 70%

The real myopia-suspect

Less time spent outdoors (<60-90 min / day)

One or two myopic parents

Binocular vision disorders(Esophoria, Accom lag, High AC/A)

Jones et al 2007, Read et al 2014, Xiong et al 2017, Gwiazda et al 2005.

Near esophoria

Accommodative lag

Higher AC/A ratios

Greater variability in accommodative responses

Myopia = inaccurate BV behaviour

Bennett et al 1989, Bullimore et al 1992, Rosenfield et al 1994, Drobe et al 1995, Gwiazda et al 1995,Abbott et al 1998, Gwiazda et al 1999, Mutti et al 2000, Rosenfield et al 2002, Vera-Diaz et al 2002, Chen et al 2003, Wolffsohn et al 2003, Nakatsuka et al 2005, Allen et al 2006, Pandian et al 2006, Harb et al 2006, Mutti et al 2006, Ciuffreda et al 2008, Vasudevan et al 2008, Lin et al 2012

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WHY SHOULD WE BOTHER ?

Because there is no ‘safe’ level of myopia

MYOPIA - Increased risk

Glaucoma Cataract RetinalDetachment

MyopicMaculopathy

< -3.00 1.65 2.1 3.1 2.2

-3.00 to -6.00 2.46 3.1 9.0 9.7

> -6.00 3.5 5.5 21.5 40.6

What to expect ?

A child should become emmetropic between 6-8 years oldSooner: predictive of future myopia

After myopia onsetNatural progression: -0,50D /year ; AL: 0.2mm /year Increased in Asian, female, youger subjects

-1D @ 8 y.o. will become -5.00 @ 16 y.o.

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GOALS: WHAT ARE THE TARGETS

Odds ratio of visual impairment by age 60

Prevalence of visual impairment by age 75

24-26mm 1 (reference) 4%

26-28mm 2 x risk 25%

28-30mm 11 x risk 27%

30mm + 25 x risk 90%

Undercorrection : form deprivation

Near work

Lightning

Tablets /Ipads : chromatic aberrations

High order aberrations

RISK FACTORS FOR PROGRESSION

Earl Smith. Vision By Design 2018

Defining the right strategy

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Contact Lens Spectrum, Volume: 31 , Issue: March 2016, page(s): 36-42

Defining a Strategy for Myopia ControlA systematic approach can help practitioners more effectively implement myopia control into practice.By Langis Michaud, OD, MSC, FAAO (Dipl), FSLS, FBCLA; Patrick Simard, OD, MBA, MSC, FAAO; & Rémy Marcotte-Collard, ODAny eyecare practitioner who has not been living on another planet for the last few years should by now be aware that myopia is no longer considered a benign refractive error that can be compensated for with regular glasses or contact lenses. In reality, thanks to the tremendous legacy of the late Prof. Brien Holden, we are now aware that myopia has become epidemic and sight-threatening.

Contact Lens Spectrum, Volume: 32 , Issue: September 2017, page(s): 20-26

Working on the 3 pillars of myopia control

Basic Principles

BinocularVision

Environmentalconditions

Optical Blur

OPTICAL 1. Contact lenses as soon as possible 2. Prescribe spectacles (progressive / bifocals) if the child is not suitable

for contact lenses.3. Consider adding low dose atropine if optical correction (CL’s or

spectacles) does not provide sufficient myopia control

CONTROL OF THE BLUR 

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The Montreal approach

Myopia Control Strategy defined :

- age /willingness to wear lenses

- how aggressive should we be

- diopters (low vs high myopes)

- ocular parameters

- asphericity vs K

- pupil size

- risk of infections /compliance

- CUSTOMIZATION CUSTOMIZATION

Customizedorthokeratologydesign allowssmaller pupils to befitted

Adjunct therapy with

Atropine 0,025% since

LAMP Study update

Customized

orthokeratology provide

highest rate of control

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Need to customize lens designs for every patient Myopia correction is not myopia control

Key elements Lens diameter: larger for myopia control Larger + zone Lens covers 90-95% corneal diameter

Central zoneNo touch : 5-10 um Distance zone vs + zone: adjust for the pupil size A smaller treatment zone is habitually required

Spherical vs toric BC

OK for refractive correction vs myopiacontrol

Return zone Determines the hydraulic tension under the lens ; CENTRATIONHigher to generate more + power Toric peripheral curves Any astigmatism > 1.50 IF limbus to limbus If elevation difference between 2 principal meridians > 30 um.

Utility of a second reservoir Centration evaluation Increased pressure in the first reservoir

Landing zone A better « seal-off » helps to generate more + Higher angle (1 step) is required in most cases

OK for refractive vs myopia control

DRL lens

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Final Design of 3MOD: 7 curves

Value (mm) Value (microns)Width r0 2,7 TLT Apex 15Width r1 0,3 TLT End of OZ Flat VariableWidth r2 0,3 TLT End of r1 Flat 75Width r3 0,7 TLT End of r2 Flat 15Width r4 0,5 TLT End of r3 Flat 0Width r5 0,5 TLT End of r4 Flat 0Width r6 0,3 TLT End of r5 Flat 15

Peripheral Edge Flat 100

Flat e correction -0,05Steep e correction -0,05

SphericDesign

Toric Design

Example on a spherical cornea

Example on a spherical cornea

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SphericDesign

Toric Design

Example on a toric cornea (-2,00 D astigmatism)

Is this working ? 

To evaluate the efficacy of customized OK lens design on a population of myopic patients 1st outcome: axial length elongation over time 2nd outcome: myopia progression over time To analyze induced corneal shape

variations based on differential tangential maps

Cohort of RGP Designer (3MOD)

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1. Treatment zone parameters were determinedbased on corneal curvatures, eccentricity andpupil

2. Total diameter and toricity of the alignmentcurve are designed to promote perfectcentration of the lens

3. The first reservoir volume is adjusted togenerate 75- 90 microns to enhance peripheralnet power

Objectives using our template

Control group: data from regular orthokeratology andsoft multifocals from non-customized patients seen inMTL were analyzed at 12 months (2012-2017)

Customized OK group: charts from newly fits (May 2017-December 2018) using RGP Designer software wereanalysed and compared to control

Exclusion criteria: previous optical myopia controlstrategy

Initial biometry was compare with 1 month post-treatment with Lenstar

Retrospective analysis

Characteristics of 3MOD Cohort

Number of charts available in RGP Designer software

500

Number of qualified charts 256

Starting year2017 622018 194

AverageStandard Deviation

Age at beginning (years) 11,7 ±2,4

60%

40%

Gender

Female Male

56%25%

1%18%

Ethnicity

Asians Caucasians Hispanics Others/Unknown

# Subjects %At least one Myopic Parent 139 54,3%

Less than 11 years old 95 38,9%

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Initial characteritics of 3MOD Cohort

96% with far exophoria: 86% with near exophoria

Mean Accommodative Lag at 40 cm: 0,73 ± 0,35 D

Mean AC/A ratio: 3,3 ± 1,8

Mean Photopic pupil size 5,65 ± 0,79 mm: Scotopic pupil size: 6,76 ± 0,59 mm

Ocular Parameters at Baseline OD OS

Axial Length (mm) 25,058 ±0,824 25,048 ±0,876Spherical Equivalent (D) -3,61 ±1,31 -3,61 ±1,38

Sim K Flat (D) 42,97 ±1,39 42,95 ±1,38Sim K Steep (D) 44,19 ±1,50 44,24 ±1,58Eccentricity Flat 0,63 ±0,10 0,63 ±0,11

Eccentricity Steep 0,47 ±0,16 0,47 ±0,15

Summary of RGP Designer Template attributes

RGP OD Average SD Minimun MaximunDefect to reduce (D) -3,20 ±0,96 -5,50 -0,50Compression Factor (D) 0,78 ±0,19 0,00 1,75Lens Power (D) 0,71 ±0,38 -2,25 2,25Total Diameter (mm) 10,65 ±0,18 10,0 11,40Toric back optic zone astigmatism (D)

-1,94 ±0,82 -1,00 -3,50

Back Optic Zone Eccentricity Value

1,00 ±1,41 0,00 2,00

Flat OD Averag

eSD

Minimun

Maximun

TLT Apex 12,5 ±24,7 -5 30TLT End of OZ

Flat 38,9 ±32,5 15,9 102,4

TLT End of r1 Flat 63,1 ±22,2 2 90TLT End of r2 Flat 13,3 ±5,2 0 60TLT End of r3 Flat 2,1 ±5,7 0 20TLT End of r4 Flat 14,5 ±5,0 0 45TLT End of r5 Flat 7,3 ±6,0 2 30TLT End of r6 Flat 14,6 ±3,1 2 25Peripheral Edge

96 6 ±12 7 50 130

65% Toric Design

12% Aspheric

BOZ

7% Toric BOZ

Comparative tangential topography analysisdone at 3 months

MARCOTTE-COLLARD, R., SIMARD, P. & MICHAUD, L. 2018. Analysis of Two Orthokeratology Lens Designs and Comparison of Their Optical Effects on the Cornea. Eye Contact Lens.

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3,84 3,18 2,953,81 3,11 3,000

0,51

1,52

2,53

3,54

4,5

4 curves design (n=64) 5 curves design (n=64) 6-8 curves design (n=452)Op

tica

l Z

one

mea

nd

iam

eter

(mm

)

Horizontal and Vertical Optical Zone mean with different orthokeratology design

Horizontal Optical Zone (mm) Vertical Optical Zone (mm)

ANOVA with Bonferroni Horizontal P Value Vertical P Value

6-8 curves vs 4 curves design 0,000 0,000

6-8 curves vs 5 curves design 0,027 0,054

4 curves vs 5 curves 0,000 0,000

6,1 5,67 4,736,94 6,13 5,696,81 5,8 4,647,02 6,64 6,560

2

4

6

8

10

12

4 curves design (n=64) 5 curves design (n=64) 6-8 curves design (n=452)Per

iph

era

l N

et P

ower

(Dio

pte

rs)

Quadrant Specific Peripheral Net Power (Diopter) with different orthokeratology design

Temporal Net Power (D) Superior Net Power (D)

Nasal Net Power (D) Inferior Net Power (D)

ANOVA withBonferroni

Temporal Net Power P Value Superior Net Power P

ValueNasal Net Power P Value

Inferior Net Power PValue

6-8 curves vs 4 curves 0,004 0,000 0,000 1,000

6-8 curves vs 5 curves 0,036 0,035 0,008 1,000

4 curves vs 5 curves 1,000 0,361 0,143 1,000

1,7 1,67 1,491,58 1,64 1,391,63 1,66 1,481,58 1,6 1,420

0,5

1

1,5

2

2,5

4 curves design (n=64) 5 curves design (n=64) 6-8 curves design (n=452)Wid

th o

f P

erip

her

al

Net

Pow

er (m

m)

Quadrant Specific Width (mm) of Peripheral Net Power with differentorthokeratology design

Width of Temporal Ring (mm) Width of Superior Ring (mm)

Width of Nasal Ring (mm) Width of Inferior Ring (mm)

ANOVA withBonferroni

Width of Temporal Ring P Value

Width of Superior Ring P Value

Width of Nasal Ring PValue

Width of Inferior Ring PValue

6-8 curves vs 4 curves 0,000 0,004 0,002 0,024

6-8 curves vs 5 curves 0,000 0,000 0,000 0,001

4 curves vs 5 curves 1 000 1 000 1 000 1 000

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y = 0,9812x + 0,4708R² = 0,9858

22,5

23

23,5

24

24,5

25

25,5

26

26,5

27

27,5

22,5 23 23,5 24 24,5 25 25,5 26 26,5 27 27,5

1 m

on

th A

xial

Le

ng

th

Initial Axial Length (mm)

Initial Axial Lenght compare to 1 month axial lenght post-treatment with Lenstar

Comparative Axial LengthN=190 Average (mm) Standard Deviation (mm)

Initial Axial Length (t=0) 25,092 ±0,8371 month Axial Length (t=1) 25,091 ±0,827

Difference:1 month-0 -0,002 ±0,100

12 months results: Myopia and Axial Length

Myopia OD Myopia OS Average (D) SD (D) Average (D) SD (D)

Customized OrthoK (3MOD) +0,47 ±0,66 +0,49 ±0,65Regular orthoK Montreal Experience -0,30 ±0,41 -0,33 ±0,41Soft Multifocal Montreal Experience -0,42 ±0,49 -0,45 ±0,51

ANOVA with Bonferroni p<0,000 p<0,000

Axial Length OD  Axial Length OS Average

(mm)SD (mm)

Average(mm)

SD (mm)

Customized OrthoK (3MOD) 0,008 ±0,226 0,029 ±0,250Regular orthoK Montreal Experience 0,122 ±0,208 0,118 ±0,258Soft Multifocal Montreal Experience 0,150 ±0,156 0,162 ±0,181

ANOVA with Bonferroni p=0,005 P=0,001

Below 10 years oldBetween 10-14

years oldOver 14 years old

Average (mm) SD (mm)Average

(mm)SD

(mm)Average

(mm)SD

(mm)Customized

OrthoK (3MOD)0,139 ±0,197 -0,030 ±0,233 -0,056 ±0,101

Regular OrthoKMontreal

Experience0,222 ±0,200 0,126 ±0,209 0,002 ±0,109

Soft Multifocal Montreal

Experience0,262 ±0,132 0,094 ±0,138 0,100 ±0,101

ANOVA with Bonferroni (3MOD

vs Regular)p=0,251 p<0,000 p=0,244

ANOVA with Bonferroni (3MOD p=0,075 p=0,025 p=0,000

Axial Length by age at the beginning of treatment

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Higher standard deviation of the topographical analysis data ofthe customized design is showing some control over the cornealshaping compare to regular orthokeratology

Customized OK designs based on pupil size lead to an increaseeffect on axial length progression over 12 months in overall datacompare to regular orthokeratology and soft multifocal contactlens

When starting before 10 years old, customized OK still beats the3 other methods, but kids are evolving more than older patientsHarder to control /Fast progressors

Discussion

Initial axial length measurement is not altered bycorneal molding

All methods of control provide a significantmanagement of myopia in term of public health andrisks of visuals impairment in adulhood butcustomized OK offer the best outcome

Further study on orthokeratology need to describethe cornea after treatment

Take home message - CONCLUSION