Comparison of Changes in Higher-order Aberrations between Conventional and Wavefront-guided LASEK

Abstract

Purpose: To evaluate the postoperative higher-order aberrations (HOAs) and factors affecting postoperative changes in HOAs in eyes that underwent wavefront-guided LASEK (laser-assisted subepithelial keratectomy), compared with the eyes that underwent conventional LASEK. Methods: We reviewed the medical records of 221 patients who had undergone LASEK or wavefront guided LASEK with VISX WaveScan and VISX Star S4 eximer laser by a single surgeon (427 total eye operations). We matched 29 eyes of the LASEK and the wavefront LASEK groups (58 eyes total) according to the guideline: preoperative refractive power differences must be within 1 diopter and preoperative root-mean-square (RMS) of total HOAs differences must be within 0.01 ?m. Preoperative wavefront aberrations and two-months postoperative wavefront aberrations and associated factors were compared and analyzed. Results: Postoperative total HOAs, comas, and spherical aberrations increased significantly from 0.36±0.10 ?m to 0.49±0.16 ?m (p=.001), 0.21±0.09 ?m to 0.31±0.14 ?m (p=.003), and 0.03±0.10 ?m to 0.10±0.20 ?m (p=.043), respectively, in the conventional LASEK group. In the wavefront LASEK group, postoperative HOAs, comas, and spherical aberrations significantly increased from 0.36±0.10 μm to 0.46±0.14 μm (p=.004), 0.18±0.10 ?m to 0.29±0.14 ?m (p=.002), and 0.09±0.14 ?m to 0.19±0.14 ?m (p=.006), respectively. There were no significant differences in HOAs between the two groups. A strong negative correlation between preoperative total HOAs and a multiple of increase in total HOAs postoperatively was found, with the negative correlation being stronger in the wavefront-guided LASEK group (Pearson’s correlation coefficient =-0.697, p