Laser in situ keratomileusis after photorefractive keratectomy for myopic regression

PURPOSE: To assess the efficacy and safety of laser in situ keratomileusis (LASIK) for regression after excimer laser photorefractive keratectomy (PRK). SETTING: Eye Research Center, Istanbul University, Istanbul, Turkey. METHODS: Laser in situ keratomileusis to treat residual myopia ranging from 1.50 to 12.50 diopters (D) (mean 5.96 D +/- 3.06 [SD]) was performed in 45 eyes of 25 patients. Cylindrical corrections were done in 7 eyes (15.6%) and spherical ablations, in 38 (84.4%). The mean interval between primary PRK and LASIK retreatment was 18.50 +/- 8.12 months. The procedure was performed under a hinged corneal flap using the Chiron Automated Corneal Shaper and Chiron Keracor 116 excimer laser. RESULTS: Six months after LASIK retreatment, mean spherical equivalent refraction was -0.67 +/- 0.77 D. Thirty-six eyes (80%) were within +/- 1.00 D of emmetropia. Uncorrected visual acuity was 20/40 or more in 31 eyes (68.9%); 2 eyes (4%) lost 2 lines of best spectacle-corrected visual acuity. There was no statistically significant difference in corneal haze before and after LASIK. CONCLUSION: Laser in situ keratomileusis was safe and effective for treating residual myopia after excimer laser PRK.