Posters

Tolerance to astigmatism evaluated for different IOL designs

Poster Details

First Author: C. Canovas NETHERLANDS

Co Author(s):    A. Alarcon   R. Rosen   M. van der Mooren   H. Weeber   P. Piers        

Abstract Details

Purpose:

The purpose of this study is to evaluate the optical and visual performance of different intraocular lens (IOL) designs in the presence of astigmatism. The comparison included a diffractive IOL designed to extend the range of vision (ERV) as well as a diffractive bifocal (+4D add power) and an aspheric monofocal IOL.

Setting:

AMO Groningen, The Netherlands

Methods:

Through focus Modulation Transfer Function (MTF) and USAF pictures were measured for different pupil sizes on an optical bench by using trial lenses to simulate up to 1D of corneal astigmatism. Additionally, a set of 46 physiological model eyes that included higher order aberrations (Weeber, Featherstone & Piers et al JBO2010) were used to predict the clinical defocus curves for the three IOL models in the presence of different levels of astigmatism.

Results:

The level of astigmatism that provided a simulated distance visual acuity of 20/20 was comparable for the monofocal and ERV designs for 3mm (1.25D) and 4mm pupil (0.75D). For the multifocal design, this tolerance was reduced to less than 0.10D for the largest pupil. The range of vision above 20/20 of the monofocal and ERV designs was not affected by 0.50D of astigmatism, being 0.50D and 1.50D respectively. On the optical bench, astigmatism reduced the best focus MTF for all IOL models. For the ERV, MTF with 0.75D of cylinder was comparable to that of the multifocal IOL without astigmatism.

Conclusions:

This study assessed the tolerance to astigmatism of different IOL models. Computer simulations and optical bench testing showed that the distance and through focus performance of the ERV design is preserved in the presence of astigmatism and demonstrates the robustness of the ERV design in the presence of astigmatic errors.

Financial Disclosure:

One or more of the authors is employed by a forNONEprofit company with an interest in the subject of the presentation