Corneal Aberrations Before and After Photorefractive Keratectomy

Abstract

Purpose To determine whether - and which - higher-order corneal aberrations, up to the sixth order, are induced by photorefractive keratectomy (PRK). Methods 197 eyes of 197 patients have been examined with a corneal aberrometer for a 3.5 and a 6.0 mm pupil simulation, both before and 1, 3, 6 months after myopic PRK treatment ranging from −15.25 D to -0.5 D (mean −5.31±2.95 D). The statistical evaluation was performed using a paired Student's T-test. Results After PRK there is a clear-cut increase in almost all the higher-order corneal aberrations for both a 3.5 and a 6.0 mm pupil simulation. These aberrations tend to normalize after 3 and 6 months mainly for a 3.5 mm simulation, whereas such normalization is not present for a 6.0 mm simulation. Conclusions PRK induces significant aberrations both for 3.5 and 6 mm pupils, 1 month after PRK, but a trend towards normalization is evident at the 6 month follow-up for the smaller pupil size.