Surface ablation outcomes in high myopia with a 6th generation excimer laser: PRK vs TransPRK

Session Details

Session Title: Surface Photoablation

Session Date/Time: Sunday 06/09/2015 | 16:30-18:00

Paper Time: 17:24

Venue: Room 10

First Author: : R.Fernandez-Buenaga SPAIN

Co Author(s): :    J. Alio   L. Casanova-Blanquer   M. Garcia Corral   A. Vega-Estrada           

Abstract Details

Purpose:

To analyze the outcomes of surface ablation in high myopia with a sixth generation excimer laser. Also to study the accuracy of conventional PRK with manual epithelial debridement compared to TransPRK in which the epithelium is removed by the laser in a non stop procedure.

Setting:

Vissum Corporation Alicante, Spain

Methods:

Prospective study of consecutive high myopic cases undergoing surface ablation. From 2008 to 2012 the surgery performed in all the cases was conventional PRK whereas in 2012, we started performing TransPRK in all the high myopic eyes. The comparative analysis was performed as soon as we achieved more than 30 eyes in the TransPRK group. The main inclusion criteria were preoperative spherical equivalent of -5.75 or more negative and no other ocular surgeries. Mitomycin C was used in all the surgeries. The outcomes were analyzed using the 6 months follow up visit data.

Results:

97 eyes were included, PRK was performed in 65 eyes and TransPRK in 32 eyes. The mean preoperative sphere, cylinder and spherical equivalent (SE) were -6.07 (sd 0.87), -1.11 (sd 1.11) and -6.62 (sd 0.7) respectively. The mean efficacy index in the PRK group was 0.86 (sd 0.21) compared to 0.98 (sd 0.11) in the TransPRK eyes (p=0.01). The mean safety index in PRK was 0.99 (sd 0.06) while in TransPRK it was 1 (sd 0.07) (p=0.64). Final SE of ± 0.5 diopters was achieved in 97% of eyes in the TransPRK group compared to 80% in the PRK group.

Conclusions:

Surface ablation with a sixth generation laser and Mitomycin C use shows good refractive outcomes in high myopia treatment. However, TransPRK achieved statistically significant better outcomes than conventional PRK in terms of refractive predictability.

Financial Interest:

NONE