Photorefractive keratectomy versus laser in situ keratomileusis for the treatment of spherical hyperopia

Objective. To compare photorefractive keratectomy (PRK) and laser in situ keratomileusis (LASIK) in treating spherical hyperopia using the VISX STAR S2 excimer laser. Intervention. Fifteen consecutive eyes of 15 patients underwent PRK, and 16 consecutive eyes of 16 patients underwent LASIK (follow-up: 12 months). Main Outcome Measures. Postoperative pain, uncorrected visual acuity (UCVA), deviation from intended correction, and loss of best spectacle-corrected visual acuity (BSCVA). Results. Mean preoperative spherical equivalent was + 2.18 diopter [D] for PRK and + 2.03D for LASIK. All PRK patients experienced significant postoperative pain that required systemic medication, whereas LASIK patients had minor and transient discomfort. Mean deviation from intended correction was -0.83D, + 0.01D, and + 0.18D at 1, 6, and 12 months after PRK, and + 0.22D, +0.30D, and + 0.40D at 1, 6, and 12 months after LASIK (P = 0.002 at 1 month). A higher proportion of LASIK eyes had a UCVA of 20/20 or better at all time points (P = 0.013 and 0.025 at 1 and 3 months, respectively). There was no statistically significant difference between both groups in BSCVA loss. Conclusions. LASIK and PRK are comparable in efficacy and safety. However, PRK was more painful, with an initial and temporary myopic over-correction that did not occur after LASIK. Stability was achieved between 3 and 6 months following PRK, and one month following LASIK.