Accuracy of ray tracing intraocular lens power calculation using anterior segment optical coherence tomography

Poster Details

First Author: K.Minami JAPAN

Co Author(s):    Y. Kataoka   J. Matsunaga   S. Otani   N. Honbou   K. Miyata  

Abstract Details

Purpose:

To evaluate ray tracing intraocular lens (IOL) power calculation using anterior segment optical coherence topography (AS-OCT) for normal cataractous eyes.

Setting:

This prospective study comprised 102 eyes of 70 patients who had cataract surgeries and obtained the postoperative best corrected visual acuity of 0.15 logMAR or better. Before the surgery, Placido topography and AS-OCT were measured within the routine preoperative examination. Predicted postoperative refractions were calculated in 3 manners: the SRK/T formula using autorefraction data; ray tracing calculation OKULIX (Tomey) using Placido topography, TMS-5 (Tomey) data; OKULIX using AS-OCT, SS-1000(Tomey) data. Refraction errors from manifest refraction spherical equivalent at 1 month postoperatively were compared. Effects of corneal eccentricity and posterior corneal curvature were also examined.

Methods:

This prospective study comprised 102 eyes of 70 patients who had cataract surgeries and obtained the postoperative best corrected visual acuity of 0.15 logMAR or better. Before the surgery, Placido topography and AS-OCT were measured within the routine preoperative examination. Predicted postoperative refractions were calculated in three methods: the SRK/T formula using autokeratometry; ray-tracing calculation OKULIX (Tomey) using Placido topography (TMS-5, Tomey); OKULIX using AS-OCT (SS-1000, Tomey). Refraction errors from manifest refraction spherical equivalent at 1 month postoperatively were compared. Effects of corneal eccentricity and posterior corneal curvature were also examined.

Results:

Between three methods no significant difference was not found in refraction error (P=0.50). The SRK/T outcomes were effected by corneal eccentricity (P=0.002), whereas ray tracing calculations did not change. OKULIX using Placido topography was effected by posterior corneal curvature (P=0.0002), however, that was not observed in using AS-OCT.

Conclusions:

Ray tracing IOL power calculation using AS-OCT was accurate and effective with least influence of corneal eccentricity and posterior curvature. FINANCIAL DISCLOSURE?: No