MYOPIA, ASTIGMATISM, HYPEROPIA…MYOPIA, ASTIGMATISM, HYPEROPIA…

PERSONALIZED PERSONALIZED TREATMENTTREATMENT

Bernard Mathys, MDBernard Mathys, MDSecretary-general of the Belgian Society of Cataract

& Refractive Surgery

Refractive surgery in 2004Refractive surgery in 2004

• How can we do this?

• Better instruments, new lasers, well-trained surgeons, improvement of post-op treatments… and new algorithms?

Today we use mostly PRK (surface treatment) and Today we use mostly PRK (surface treatment) and Lasik to perform surgery and our desire is to Lasik to perform surgery and our desire is to improve our resultsimprove our results

Algorithm factorAlgorithm factor

Different steps are needed:

• Improve the treatment itself: -3 of X is not Improve the treatment itself: -3 of X is not necessarily -3 of Ynecessarily -3 of Y• Personalize treatment =>Improve quality of Personalize treatment =>Improve quality of visionvision• Possibility to help people with thin corneas, Possibility to help people with thin corneas, large pupils, high ametropialarge pupils, high ametropia

Carefull preop examinationCarefull preop examination

Technologically advanced Laser Technologically advanced Laser

Zyoptix: the name of the systemZyoptix: the name of the systemThe laser custom treatmentThe laser custom treatment

LasikLasik

The interventionThe intervention - - making the flapmaking the flap

LasikLasik

ClosingClosing the flap the flap

HOW DOES HOW DOES «PERSONALIZED «PERSONALIZED

TREATMENT»TREATMENT»WORK ?WORK ?

The ideaThe idea

The ideaThe idea

Wavefront analyseWavefront analyseReconstruction of wavefront by CCD-imageReconstruction of wavefront by CCD-image> Zernike coefficient> Zernike coefficient

CCD-Image

Hartmann-Shack WavefrontHartmann-Shack Wavefront MeasurementMeasurement

Perfect Eye

Aberrated Eye

Lenslet Array CCD

ArrayWave Aberration

Spot Array

Wave Aberration of a SurfaceWave Aberration of a Surface

The shape of the wavefront is depicted in Zernike The shape of the wavefront is depicted in Zernike coefficient, each shape describes a deformationcoefficient, each shape describes a deformation

trefoil coma coma trefoil

quadrafoil secondary spherical

2nd

3rd

4th

5th

radialorder

secondaryquadrafoil

pentafoil secondary secondarysecondarypentafoilsecondary

defocusastigmatism astigmatism

astigmatism astigmatism

trefoiltrefoil comacoma

Z20

Z 2-2 Z2

2

Z 3-1 Z3

1Z 3-3 Z3

3

Z40 Z4

2Z 4-2 Z4

4Z 4-4

Z51Z 5

-1 Z53Z 5

-3 Z55Z 5

-5

ConventionalRefraction

Higher OrderAberrations

Zernike ModesZernike Modes

Point Spread Function (PSF)Point Spread Function (PSF)Point Spread Function: is the representation of an Point Spread Function: is the representation of an optical system of a punctual and distant light optical system of a punctual and distant light source ( star in the sky)source ( star in the sky)

Airy Disc

Point Spread Function vs. Pupil SizePoint Spread Function vs. Pupil SizePerfect EyePerfect Eye

Point Spread Function vs. Pupil SizePoint Spread Function vs. Pupil SizeTypical EyeTypical Eye

Each eye has different patternsEach eye has different patternsof High Order Aberrations.of High Order Aberrations.

Wave Aberration

PointspreadFunction

Retinal Image

Perfect eye(diffraction limited) MRB GYY MAK

5.7 mm pupil

Encouraging resultsEncouraging results

Encouraging resultsPreop –6.5 D Encouraging resultsPreop –6.5 D ZyoptixZyoptix

Postop Plano 6M VA 13/10Postop Plano 6M VA 13/10

Zyoptix System – Clinical OutcomesZyoptix System – Clinical Outcomes

Quality of Vision after surgery % (n)

No improvement 0,3% (1)

Slight improvement 1,2% (4)

Moderate improvement 1,8% (6) Marked improvement 12,1% (41) Extreme improvement 84,7% (288)

Night visionNight vision

HaloesHaloes

Custom treatmentCustom treatment

NEW SCALE ?NEW SCALE ?

• Contrast & low-contrast sensitivity•Different lightning conditions•Color vision•Glare & haloes

• VA is a less sensitive measure of the correction VA is a less sensitive measure of the correction of high-order aberrationsof high-order aberrations• Increase the quality of the retinal imageIncrease the quality of the retinal image• We need to assess quality of vision in true-life We need to assess quality of vision in true-life conditions:conditions:

Custom treatment: the future ?Custom treatment: the future ?

• AberrometryAberrometry•TopographyTopography•Linked to the laser, to achieve personal Linked to the laser, to achieve personal treatmenttreatment•Must improve our actual results in all casesMust improve our actual results in all cases•Must be safeMust be safe•Not a higher complication rateNot a higher complication rate

20/20/20/2020/20/20/20

THANK YOU FOR THANK YOU FOR YOUR ATTENTIONYOUR ATTENTION

Bernard Mathys, MDBernard Mathys, MDSecretary-general of the Belgian Society of Cataract & Refractive Surgery