Wavefront guided versus Wavefront Optimized Lasik A Contralateral Comparative Study

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Wavefront guided versus Wavefront Optimized Lasik
A Contralateral Comparative Study
Dr. Prema Padmanabhan Dr. Subam
Basuthkar Dr. Sitalakshmi Guruswamy Mr.
Roy Joseph Medical Research Foundation 18
College Road, Chennai, Tamil Nadu, INDIA The
authors have no financial interests in any of the
devices used in the study.

• Poster ID 296789

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• PURPOSE
• To compare the outcome of wavefront guided (WFG)
  with wavefront optimized (WFO) Lasik in fellow
  eyes of myopes.
• DEFINITION
• WFG Customized treatment based on individual
  wavefront data.
• WFO Treatment software designed with
  pre-programmed corrections.
• TYPE OF STUDY
• Prospective, non-randomized controlled.

Material Methods

• Outcome measures
• Refractive outcome
• Wavefront aberration profile
• Contrast sensitivity

N 54 eyes of 27 patients Mean age 24.7
3.7 (18-32) yrs Sex M 12 F
15 S.E - 4.36 1.22 D Eye with more HOA
WFG Lasik Fellow eye WFO Lasik Follow up
1 month
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Pre-op ocular parameters
p 0.608 p 0.673 p 0.033
WFG Lasik (n27) - 4.28 1.17 0.039 0.08 0.580
0.137 6.5
WFO Lasik (n27) - 4.45 1.25 0.016 0.27 0.506
0.109 6.5

• PARAMETER
• Mean S.E (D)
• Mean BSCVA (log MAR)
• Mean RMS of HOA (?)
• Optical zone of treatment
• (mm)

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Hansatome (B L) Flap dia 9.5mm Allegretto
Excimer Laser (flying spot) Beam dia
0.95mm. Allegretto Wave Analyser. Pupil dia
6.5mm FACT chart 1.5, 3, 6, 12, 18 cpd

• LASIK FLAP
• LASIK
• ABERROMETRY
• CONTRAST SENSITIVITY

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Results
96
93
Predictability
Refractive Outcome Predictability within
target refraction Efficacy UCVA Safety
Change in BCVA
p0.58
of eyes
7
4
0
0
0
0
0
0
0
0
0
0
lt-2
-1.01 to -2
-0.51 to -1
- 0.5
0.51 to 1.00
1.01 to 2
gt2
Postop SE (D)
80
Safety
74
Efficacy
70
p0.518
63
p0.316
60
50
of eyes
40
30
22
20
11
11
11
10
4
4
0
0
0
0
0
0
0
Lost gt2
Lost 2
Lost 1
Unchanged
Gain 1
Gain 2
Gain gt2
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Results Wavefront Profile Definitions
Y
Induced change Post op Pre op
Y
No change
Worsened
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Results Wavefront Profile - Induced aberrations
(Pupil diameter 6.5mm)
Induced aberrations (?m)
Zernike Terms (2nd 6th order)
Induced aberrations (?m)
Zernike Terms (3rd 4th order)
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Induced change Z 04 (spherical aberration)
based on pre-op-direction of aberration
Results
WFG
WFO p

Z 04 ve 0.11 0.14
0.20 0.10 0.01 n 13

Z 04 ve 0.27 0.20
0.27 0.17 0.93 n 14
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Induced change in aberrations
WFG
WFO
Perfect correction ns
ns Under correction
Z -13 ns Over
correction Z -33, Z 44
ns No change
ns ns Worsened
ns
Z 33, Z -13
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Simulated Retinal image quality
OS WFO Preop Postop
OD WFG Preop Postop
C1 C2 C3 C4 C5 C6 C7 C8 C9 C10 C11 C12 C13 C14
0.26 -0.41 0.02 6.72 -1.21 0.04 0.12 0.24 -0.02 0
-0.02 0.03 0.02 -0.05
-1.08 -0.22 0.56 1.28 -0.43 0.22 -0.37 0.03 -0.21
0.09 -0.06 0.25 0.05 -0.1
0.16 0.47 0.34 5.67 -0.93 -0.06 0.24 0.23 0.07 0.0
6 0.04 0.04 0.01 -0.04
-0.32 -0.11 0..14 0.75 0.18 0.04 0.01 -0.01 0.05 -
0.05 0.03 0.02 -0.06 -0.09
WFG Defocus 0
WFO Defocus 0
RMS-HOA
RMS-HOA
Pre-op 0.33
Pre-op 0.29
Post-op 0.58
Post-op 0.16
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Contrast sensitivity
Spatial Frequency in cycles per degree
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Conclusions

• Refractive outcomes of WFG WFO Lasik were
  comparable
• WFG Lasik induced less aberrations than WFO
• WFG induced significantly less Z04 in eyes with
  preop ve Z04
• WFG Lasik improved contrast sensitivity in
  spatial frequencies 3, 6, 12 cpd compared to
  pre-op log values, whereas WFO Lasik caused a
  drop in contrast sensitivity at all spatial
  frequencies.

Thank you