Posters

Characteristics of astigmatism and posterior astigmatism of patients with a toric intraocular lens

Poster Details

First Author: J.Lee SOUTH KOREA

Co Author(s):    Y. Kwon              

Abstract Details

Purpose:

To evaluate the characteristics of astigmatism and posterior astigmatism in patients with a toric intraocular lens implantation.

Setting:

Kim's Eye Hospital, Seoul, Korea.

Methods:

126 eyes with a toric intraocular lens implantation by single surgeon were examined retrospectively between January 2013 and December 2013. Toric intraocular lens implantation was performed the patiens with corneal astigmatism more than 1.2D. Preoperative and postoperative manifest refraction were measured. Corneal astigmatism was evaluated by IOL master® (CarlZeiss, Jena, Germany), Sirius® (Costruzionestrumentioftalmici, Florence, Italy). Posterior corneal astigmatism measuremens are made by Sirius® (Costruzionestrumentioftalmici, Florence, Italy). Eyes were divided three groups depending on the anterior corneal steep meridian measured by the IOL master. (1) vertical group with corneal steep meridian at 60 to 120 degrees and (2) horizontal group with corneal steep meridian at 0 to 30 degrees or 150 to 180 degrees and (3) oblique group with other degrees corneal steep meridian. Two types of toric intraocular lens: AcrySof® IQ Toric IOLs (T3, T4, T5, T6, T7, T8), Toric-TECNIS® Aspheric IOLs (ZCT150, ZCT225, ZCT300, ZCT400) were implanted. Statiscal Analysis were performed using SPSS version 12.0. A probability of less than 5% (P <0.05) was considered statiscally significant

Results:

126 eyes of 96 patients were enrolled. The mean corneal astigmatism was 1.93D by IOL master and 1.89D by Sirius. With the Sirius that measure posterior corneal curvature, the mean posterior astigmatism was 0.42D. 85(67.5%) of patients were grouped in vertical goup and 36(28.1%) were in horizontal group and 5(4%) of patients were in oblique group. In correlation analysis of corneal astigmatism on anterior and posterior corneal surface, the magnitude of astigmatism on the anterior corneal surface and posterior corneal surface grouped according to the orientation of the steep meridian on the anterior cornea showed no correlation in each group. Compare the magnitude of corneal astigmatism of IOL master® and SIRIUS®, they showed significantly same value. The percentage of eyes with vertical, horizontal, and oblique steep meridian in each decade on anterior surface and posterior surface showed horizontal goup was increased with age but posterior astigmatism showed not definite change with age. After consideration of posterior astigmatism, the perfect success rate was increased but there was no significant change.

Conclusions:

There is no correlation of magnitude with anterior and posterior coneal astigmatism in all type of corneal astigmatism. Anterior corneal astigmatism tend to change to aganist the rule astigmatism with aging but there is no change of posterior astigmatism with aging. Consideration of posterior astigmatism could be helpful for the better success but no significant change of surgical success. FINANCIAL INTEREST: NONE