Abstract
Purpose:
To evaluate the optical performance of different possibilities of implants in a high hyperopic eye
Methods:
IOL models were designed and optimized in an optical design software (Radiant Zemax® v13.0. LLC, Redmond, WA) using a modified Liou and Brennan eye model. Four different IOL powers were created: 20, 30, 40 and 60D lens. All the lenses were aspheric and optimized to have spherical aberration equal to zero. A different modified Liou and Brennan eye model with dimensions comparable to a nanophthalmic eye was used for testing 5 different implant options. Option 1: a single 60D IOL. Option 2: two 30D lenses. Option 3: a 20D IOL (anteriorly) and a 40D lens (posteriorly). Option 4: a 40D lens (anteriorly) and a 20D IOL (posteriorly). Option 5: three 20D lenses. A 3 and 5mm pupils were used. The total root mean square (RMS) of the wavefront error and spherical aberration were recorded for analysis. The area under modulation transfer function (MTF) curve was calculated and normalized by the diffraction limit.
Results:
MTF analysis shows that the single aspheric high-power IOL had the closest curve to the diffraction limit of the eye. For the 5mm pupil, the area under the MTF curve normalized by the diffraction limit was 0.4619 for the single IOL and 0.2867 ± 0.0256 (p=0.001) for the piggyback models. Total wavefront RMS error was 0.3202µm for the 60D lens and 0.0694 ± 0.0512µm (p=0.001) for the multiple implants and the spherical aberration was 0.1809µm versus 0.3207 ± 0.0284µm respectively (p=0.002).
Conclusions:
The computer simulation showed that one single high-power aspheric IOL had a better optical performance than piggybacking lower-power aspheric IOLs. MTF analysis revealed that a single high-power lens provides higher contrast sensitivity when compared to the piggyback options.
Keywords: 567 intraocular lens •
626 aberrations •
630 optical properties