Bilateral comparison of conventional versus topographic-guided customized ablation for myopic LASIK with the NIDEK EC-5000

Abstract

Purpose: To compare visual acuity and higher order aberrations before and after myopic LASIK using conventional versus customized ablation.

Methods: This prospective, randomized study included 54 myopic eyes in 27 patients who underwent bilateral LASIK using the NIDEK EC-5000 excimer laser system (NIDEK Technologies, Gamagori, Japan). Customized aspheric treatment zone (CATz) treatment was used in one eye (CATz group) and conventional ablation (conventional group) was used in the fellow eye. Uncorrected visual acuity (UCVA) and higher order aberrations (root-mean-square [RMS] in 4-mm and 6-mm zones) of both groups were observed with the NIDEK OPD-Scan aberrometer before and 3 months after LASIK. Preoperative mean refractive error was similar for both eyes of each patient (P>.05).

Results: No statistically significant differences were noted in preoperative higher order aberrations (RMS in 4-mm and 6-mm zones) between groups (P>.05). No statistically significant difference was noted between pre- and postoperative higher order aberrations in the CATz group (P>.05). However, a highly statistically significant increase in higher order aberrations was observed after conventional ablation (P<.001). There was a statistically significant higher increase of higher order aberrations after LASIK in the conventional group than the CATz group (P<.05). Postoperative UCVA with both conventional and customized ablation was not significantly different (P>.05).

Conclusions: LASIK with conventional ablation and CATz ablation resulted in the same UCVA. The increase in higher order aberrations after CATz ablation was less than after conventional ablation.