Posters

Comparison of ray-tracing method (Okulix®) and SRK/T thin-lens formula in intraocular lens power calculation

Poster Details

First Author: I.Martinez-Soroa SPAIN

Co Author(s):    I. Recalde Beitia   L. Bascaran Oteyza   A. Chamoun Olea   L. Ansa Echegaray   J. Mendicute del Barrio        

Abstract Details

Purpose:

To compare the accuracy of the SRK/T thin-lens and ray-tracing (Okulix® software) methods in intraocular lens (IOL) power calculation in normal eyes.

Setting:

Donostia University Hospital, Ophthalmology department. San Sebastián, Spain.

Methods:

Eyes of normal cataract patients were retrospectively studied. Preoperatively, patients were analyzed axial length, keratometry and IOL power calculation with SRK/T formula by IOLMaster® software. Afterwards the corneal radii curvature and surface elevation dates were analyzed by Tomey® Scheimpflug tomography (TMS-5). Secondary, IOL power calculation was measured by ray-tracing Okulix® software. All patients had uneventful phacoemulsification and EnVista MX60 (Bausch&Lomb) IOL implantation by the same surgeon.

Results:

87 normal eyes of 46 patients were included. The mean preoperative refraction was +0,74 ± 2,22 D. Axial length was 23,02 ± 0,69 mm. The mean keratometry was 44,19 ± 1,26 D. One month after surgery, the mean postoperative refraction was +0,01 ± 0,33 D. The mean arithmetic prediction error was -0,22 ± 0,20 for Okulix® and -0,19 ± 0,18 for SRK/T formula (p: 0,0627). The median absolute prediction error was 0,22 for Okulix® and 0,3 for SRK/T (p: 0,0092). The relation between corneal anterior and posterior radii curvature was 1,19 ± 0,02.

Conclusions:

There was no statistically difference in mean arithmetic prediction error between ray tracing and SRK/T thin-lens formula in normal eyes, although in absolute values the ray tracing had better accuracy for IOL power calculation.

Financial Disclosure:

NONE