Zernike

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Design of New Aspheric Ablation Profiles with
Modified Zernike Polynomials to Improve
Presbyopia and Night Vision Problems
using Advanced Surface Ablation (ASA80
/ASA-Lasek )
1 year- follow-up Preliminary Results of a
Multicenter Study
S. Lee 1,2 Dan Z. Reinstein 3, E. Schroeder 4
H. Lee 1 J.C. Kim 2 1 ASA80/ASA-Lasek- GM
Eyeclinics Seoul, Korea 2 ASA80/ASA-Lasek -
Refractive Center Chung Ang University Seoul,
Korea 3 London Vision Clinic, England 4 Carl
Zeiss Meditec, Jena, Germany
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• Study Design
• Prospective multi-center clinical trial (between
  01/2006 and 01/2008)
• Total of 43 eyes of 26 consecutive patients Age
  (mean) 34.37 6.18 years
• All eyes treated with Individual New Aspheric
  Customized Ablation Profiles (NAP) by adding a
  shotfile with a negative spherical aberration
  Z4(0) to shift the spherical aberration into the
  plus range
• Mean Spherical Equivalent (MRSE)
• Myopia - 6.32D 2.65 D (Myopia -0.75D to
  -14.75D
• Astigmatism -0.50D to -6.00D
• Hyperopia 2.49D 1.45 D (Hyperopia
  0.75D to 4.00D
• Astigmatism -0.50D to -6.00D)
• Add requirement (mean) 1.98D 0.41D ( Near
  Vision lt Nieden 4 )
• All eyes treated with the MEL-80 Spotscanning
  Excimer Laser (Carl Zeiss Meditec, Jena, Germany)

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• Advanced Surface Ablation (ASA80 / ASA-Lasek
  ) in all cases

• MEL80 Ablation Profiles
• TSA (Tissue Saving Ablation) Type
  Munnerlyn-profile with k-value compensation
• ASA (Aberration Smart Ablation) Type TSA plus
  aspheric component
• NAP New-individual-Aspheric-ablation-Profiles

ASA Z(4,0) ? Addition of negative spherical
aberration ?

• Statistical Analyses SPSS v.15.0
• All tests used were non-parametric, based on
  Kolmogorov- Smirnov-Test
• no parametric t-test for significance instead
  Wilcoxon, Mann-Whitney-U,
• Kruskal-Wallis-Test (plt 0.05)

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Clinical Results
Gain of 4.5 lines in Nieden (72)
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p lt.05
p lt.05
postop lt preop (p gt.05)
9 (plt.05)
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• Case Reports
• Myopic Patients
• Z(4,0) vs Pupil Diameter
• Depth of Focus
• Control of Refraction vs
• Pupil Diameter

ASA-Profile
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ASA Z(4,0)
Patient hyperopic (overcorrected) under bright
daylight and mesopic condition
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ASA Z(4,0)
Patient myopic (undercorrected) under bright
daylight and mesopic condition
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ASA Z(4,0)
positive

• Patient
• myopic under bright
• daylight and
• plano under mesopic
• condition

Ideal outcome!
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Design of Refraction vs Pupil Diameter
Bright Light Vision
Mesopic Vision
Bright Light Vision
Mesopic Vision
Myosis
Myosis
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Summary
Customized correction of spherical aberrations
improve contrast sensitivity, mesopic contrast
sensitivity and especially near vision and
reduces presbyopia in myopic, hyperopic and even
in high myopic and hyperopic cases
Conclusion
Perfect design of an ablation profile with a
negative spherical aberration for presbyopic eyes
should
increase depth of focus for far vision
set bright light refraction below plano (around
0.75 D)
avoid inducing night myopia, have mesopic
refraction around plano