Ten-year Follow-up of Photorefractive Keratectomy for Myopia of Less Than −6 Diopters

Abstract

To evaluate the long-term outcomes of excimer laser myopic photorefractive keratectomy (PRK) for myopia of less than -6 diopters (D). Long-term (10-year) follow-up retrospective, interventional case series. The study included 225 eyes of 138 myopic patients with spherical equivalent (SE) between 0 and -6 D treated with myopic PRK at the Instituto Oftalmológico de Alicante, Alicante, Spain, using the VISX 20/20 excimer laser (Santa Clara, California, USA). The main outcome measures were refractive predictability and stability, mean corneal keratometry, topographical cylinder, safety, efficacy, stability of visual acuity, and postoperative complications. At 10 years, 169 (75%) of 225 eyes were within +/- 1.00 D and 207 (92%) were within +/- 2.00 D. Ninety-five (42%) eyes underwent retreatments because of overcorrection, regression, or both. The mean SE slightly decreased (myopic regression) with a mean magnitude of -0.10 +/- 1.08 D over 10 years (-0.01 +/- 0.11 D per year). Forty-one (58%) of 225 eyes demonstrated increase in best spectacle-corrected visual acuity after 10 years. Only one eye lost eight lines because of significant cataract, and two eyes lost vision (one lost seven lines and the other lost four lines) because of posterior segment-related complications. The mean corneal haze score gradually decreased from 0.22 +/- 0.39 at three months to 0.01 +/- 0.09 at 10 years. Photorefractive keratectomy for myopia of less than -6 D is a safe and effective procedure in the long-term.