Title: Variations%20in%20refractive%20analysis%20with%20different%20diffractive%20multifocal%20intraocular%20lenses%20using%20different%20wavefront%20analyzers
1Variations in refractive analysis with different
diffractive multifocal intraocular lenses using
different wavefront analyzers
Mami Yoshino, Hiroko Bissen-Miyajima, Shinichi
Oki, Keiichiro Minami, Kunihiko Nakamura
Department of Ophthalmology Tokyo Dental College
Suidobashi Hospital, Tokyo, Japan Naoyuki
Maeda Department of Ophthalmology Osaka
University Medical School, Osaka, Japan
Yoshino, Bissen-Miyajima, Oki, Minami and
Nakamura No financial Interest Maeda Research
grant recipient from Topcon Corp.
2PURPOSE
It is still under discussion whether the
Hartman-Shack wavefront analyzer represents real
wavefront aberration of the multifocal
intraocular lens (MF-IOL) implanted eye. This
study evaluated the refractions of diffractive
MF-IOL implanted eyes using two wavefront
analyzers with manifest refraction.
3SUBJECTS
15 eyes of 8 patients who received diffractive
MF-IOL
MF-IOL ZM900 (AMO) SA60D3 (Alcon)
No. of eyes (patients) 9 (5) 6 (3)
Gender (MaleFemale) 14 03
Age (years) 66.05.3 59.714.7
Corneal astigmatisms 0.5 D 0.5 D
Time of evaluation 3-14 months post-op 3-14 months post-op
4METHODS
To verify if the wavefront analyzer results
represent real wavefront aberration, refraction
data were compared with those with manifest
Manifest Refraction
VS 0.9 (1.2 x 0.75D sph. cyl. -0.75 D)
Spherical refraction
Refraction by wavefront analyzer
Cylindrical refraction
- KR-9000PW (Topcon, Japan)
- WaveScan (AMO, US)
5 Wavefront Analyzer KR-9000PW WaveScan
Wavefront sensor Hartmann-Shack Hartmann-Shack
No of spots (7 mm pupil) 169 points 240 points
Wavelength at measure 840 nm 785 nm
Centering point Corneal apex Pupil center (scotopic)
Examination room Room light Dim light (5cd/m2 )
Pupil Dilated Scotopic
Refraction Spectacle plane Spectacle plane
6Hartmann-Shack spot images and evaluation
WaveScan
KR-9000PW
ZM900
SA60D3
ZM900
SA60D3
Spots were doubled
Spots were clearer in the center
Analysis difficult due to spot irregularity
Spots were doubled or not clear
Optical zone 4 mm 6 mm
Optical zone 5.940.75 mm
Evaluation was possible in all eyes tested
3 eyes failed for evaluation
7RESULTS
KR-9000PW
Manifest Wavefront Difference p value (Wilcoxon)
Sphere (D)
Total 0.270.52 0.520.49 0.250.30 plt0.05
ZM900 0.170.33 0.570.25 0.400.13 plt0.01
SA60D3 0.420.74 0.450.75 0.040.36 p0.917
Cylinder (D)
Total -0.620.43 -0.980.45 0.360.38 plt0.01
ZM900 -0.470.46 -0.700.31 0.220.32 p0.086
SA60D3 -0.830.30 -1.100.69 0.580.40 plt0.05
8RESULTS
WaveScan
Manifest Wavefront Difference P value (Wilcoxon)
Sphere (D)
Total 0.270.52 1.040.51 0.710.56 plt0.05
ZM900 0.170.33 1.070.50 0.880.41 plt0.05
SA60D3 0.420.53 0.980.53 0.340.62 p0.273
Cylinder (D)
Total 0.620.43 -0.940.60 0.320.41 plt0.01
ZM900 0.470.46 -0.690.37 0.160.29 plt0.05
SA60D3 0.830.30 -1.450.36 0.640.52 p0.144
9DISCUSSION
Reliability of refraction with Hartmann-Shack
analyzer
- The difference of spherical and cylindrical
refractions between manifest and wavefront were
within 0.5D. - Coincidence in refraction may support that
Hartmann-Shack analyzer measures distance
wavefront of diffractive MF-IOL properly.
10DISCUSSION
Differences between 2 wavefront analyzers
- Cyrindrical refraction was very close between
KR-9000PW and WaveScan. - With KR-9000PW, spherical refraction was closer
to manifest.
Differences between 2 multifocal IOLs
- Hartmann-Shack images were clearer and easier to
be analyzed in eyes with ZM900.
11CONCLUSION
- In this preliminary study, the difference between
the wavefront refraction and manifest refraction
can be influenced by the design of the
diffractive MF-IOL and the characteristics of the
wavefront analyzer. - These effects should be considered for not only
2nd order aberration, but also higher order
aberration in eyes with diffractive MF-IOLs.
12REFERENCES
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Postoperative wavefront analysis and contrast
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Apodized diffractive versus refractive multifocal
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