Posters

Light distribution in bifocal and trifocal diffractive intraocular lenses

Poster Details

First Author: C.Ortiz SPAIN

Co Author(s):    L. Belda-Salmerón   J. Esteve-Taboada   T. Ferrer-Blasco   R. Montés-Micó     

Abstract Details

Purpose:

Multifocal intraocular lenses (IOLs) have been designed as solution for reducing dependence on spectacles, however exist different designs of IOL depending on the multifocal technology used. The aim of this study is to compare the variation in light distribution to far and near foci for different bifocal and trifocal IOLs, as a function of pupil size.

Setting:

University of Granada and University of Valencia, Spain

Methods:

The study evaluated three different IOLs: the bifocal Acri.LISA 366D (Carl Zeiss Meditec) and two trifocal IOLs, the AT LISA tri 839MP (Carl Zeiss Meditec) and the FineVision IOL (PhysIOL). The AT LISA tri 839MP and Acri.LISA 366D IOLs have a diffractive design, whereas the FineVision IOL combines two distinct apodized bifocal diffractive structures resulting in three foci. The energy distribution for each focus (far, intermediate, and near) and for different pupil sizes was evaluated in vitro using the PMTF optical bench (Lambda-X Co) with an aberration-free model cornea.

Results:

The distribution of the light energy was asymmetric for far/intermediate/near focus at each pupil size studied. The introduction of an intermediate focus point implied a slight loss of the far focus energy, but comparable in the near focus with a bifocal IOL. In addition, we found that for both trifocal IOLs, the light energy available for far vision increased with aperture size, decreasing the light energy allocated to intermediate and near vision, respectively. On the other hand, the FineVision IOL showed the better results for distance vision in mesopic conditions, however the AT LISA tri 839MP showed better results in near vision for lager pupil diameters.

Conclusions:

The best results at the far focal point obtained with the FineVision IOL could be related to the apodized trifocal design. Implantation of trifocal multifocal IOLs with asymmetrical light distribution could be an alternative to spectacles providing good vision at far, intermediate and near distances. In addition, the surgeons could provide information to the patients about which IOL has the best performance according to illumination-conditions. FINANCIAL INTEREST: NONE