Comparison of Higher-Order Corneal Aberrations: Conventional Penetrating Keratoplasty vs. Femtosecond Laser Keratoplasty vs. DSEK

Abstract

Purpose: : To evaluate higher-order anterior corneal aberrations between three different keratoplasty techniques: conventional penetrating keratoplasty, femtosecond laser keratoplasty with a "zig-zag" pattern incision, and descemet stripping endothelial keratoplasty (DSEK).

Methods: : Anterior corneal higher-order aberrations of four eyes of four patients who had conventional penetrating keratoplasty, five eyes of five patients who had femtosecond laser keratoplasty with a "zig-zag" pattern incision, and four eyes of four patients who had DSEK were compared using Zernike polynomial values obtained from Pentacam corneal topography. Mean Zernike polynomial values for 3^rd to 8^th order aberrations from each keratoplasty technique was compared for statistical significance using student T test. Both conventional penetrating keratoplasty and femtosecond laser keratoplasty were performed with a 24-bite running suture technique.

Results: : In this small series to date, there was a statistically significant lower amount of coma when comparing the mean Zernike values of the femtosecond laser "zig-zag" incision pattern keratoplasty (2.2042) and DSEK (0.9608) to conventional penetrating keratoplasty (3.5254) six-months to two years postoperatively. There was no statistically significant difference when comparing spherical aberrations or other higher (4^th to 8^th order) aberrations of the anterior cornea between the three different keratoplasty techniques.

Conclusions: : Preliminary results suggest that when evaluating anterior corneal higher-order aberrations, the femtosecond laser keratoplasty "Zig-Zag" pattern keratoplasty and DSEK lead to decreased coma compared to conventional penetrating keratoplasty. Analysis of more cases is ongoing.

Keywords: refractive surgery: corneal topography • refractive surgery: optical quality • refractive surgery: comparative studies