Posters

The effect of decentration and tilt in optical quality of a toric trifocal multifocal intraocular lens

Poster Details

First Author: E.Papadatou SPAIN

Co Author(s):    L. Belda-Salmerón   G. Zoulinakis   D. Madrid-Costa   T. Ferrer-Blasco   R. Montés-Micó  

Abstract Details

Purpose:

To evaluate the in vitro optical quality of a toric trifocal intraocular lens (MTIOL) by inducing different degrees of decentration and tilt using two different corneal models.

Setting:

University of Valencia, Spain.

Methods:

AT LISA tri toric 939MP (Zeiss) +3.75 diopters (D) IOL with 3 main foci was evaluated for various degrees of decentration and tilt, starting with the lens at a centered position without tilt. The PMTF optical bench (Lambda-X) was used to quantify the optical quality via the modulation transfer function (MTF) with an aberration - free model cornea and an aberration model cornea, for 3.0 mm and 4.5 mm pupil sizes respectively.

Results:

The results showed the highest MTF value with the aberration - free model cornea for 3.0 mm pupil when the lens was well - centered and without any degree of tilt. The gradually increasing decentration and tilt led to lower MTF values for both corneal models and both aperture diameters. The aberration - free model cornea led in all cases to better MTF values compared to the aberration model cornea. Respectively, the 3.0 pupil led to better MTF values compared to the 4.5 pupil for both corneal models.

Conclusions:

The results showed that decentration and tilt led to a gradual deterioration of the optical quality of the IOL, which was more evident at the 4.5 mm aperture diameter for the aberration model cornea. This underlines the necessity of accurate centration, without tilt on the lens when it is implanted in order to minimize the danger of negative postoperative effects in visual performance. Finally, the pupil size and the corneal aberrations are factors that have to be evaluated before the surgery. FINANCIAL INTEREST: NONE