Toric intraocular lens calculation with different devices

Session Details

Session Title: Pseudophakic IOLs: Toric & Multifocal

Session Date/Time: Tuesday 08/09/2015 | 08:00-10:30

Paper Time: 08:24

Venue: Room 11

First Author: : C.Azenha PORTUGAL

Co Author(s): :    N. Oliveira   M. Silva   A. Rosa   M. Quadrado   J. Murta        

Abstract Details

Purpose:

Perfect astigmatism correction with toric IOL implantation requires an accurate corneal astigmatism evaluation and a precise surgical procedure. The purpose of our study is to compare keratometric values obtained with different devices and assess the manifest refractive errors after toric intraocular lens implantation.

Setting:

Department of Ophthalmology, Centro Hospitalar e Universitário de Coimbra, Coimbra, Portugal. Faculty of Medicine, University of Coimbra, Coimbra, Portugal. Unidade de Oftalmologia de Coimbra, Coimbra, Portugal.

Methods:

Prospective study. Thirty-two eyes of 23 consecutive patients with topographic astigmatism higher than 1.5 D underwent toric IOL implantation for cataract surgery and astigmatism correction (AcrySof® IQ ReSTOR® Multifocal Toric IOL +3.0 D and AcrySof® IQ Toric IOL, Alcon). Keratometric values obtained with different devices: ALLEGRO BioGraph (Wavelight) biometer, IOLMaster V.5 (Carl Zeiss Meditec), Pentacam rotating Scheimpflug camera (Oculus) and Verion Image Guided System (Alcon) were analyzed. Individual and aggregate data analysis of the changes in refractive error due to surgery were performed using simple subtraction and vector analysis of astigmatism according to the Alpins method.

Results:

At 3-month post-op, manifest difference vector (DV), surgically induced astigmatism (SIA) and target induced astigmatism (TIA) mean vectors were 0.34x92.37º, 1.20x65.93º and 1.16x105.99º, respectively (D). The mean correction index was 0.95±0.18; 94.69±18.15% of the astigmatism was corrected, index of success of 0.19±0.21 and -0.15±0,5 magnitude of error. Corneal astigmatismal power and IOL cylindrical power chosen by the online calculator was significantly different between devices (p=0.015 and 0.19), but axis was not (p=0.698). Despite the trend to an increased accuracy of Pentacam, none of the devices showed a clear superiority in predicting the best IOL cylindrical power.

Conclusions:

On the basis of the clinical results of this study, toric IOL implantation was good in all refractive measures for cataract surgery and astigmatism correction throughout a 3-month observation period.

Financial Interest:

NONE