Incidence and associations of retreatment after LASIK.

PURPOSE To determine the incidence and risk factors for laser in situ keratomileusis (LASIK) retreatment and to present a novel retreatment technique. DESIGN Retrospective noncomparative consecutive case series. PARTICIPANTS Two thousand four hundred eighty-five eyes (1306 patients) underwent LASIK surgery for myopia, hyperopia, or astigmatism using either the Summit Apex Plus or the Alcon LADARVision excimer laser systems. Only retreatments for residual refractive error were included. MAIN OUTCOME MEASURES Prevalence and incidence of retreatments were determined. Potential risk factors for retreatment, including age, gender, and attempted correction, were assessed. Refractive error and a ratio of residual sphere to cylinder in retreated eyes were also analyzed. RESULTS Of the total cohort studied, 288 eyes of 233 patients underwent one retreatment, and 3 eyes of 3 patients required two retreatment procedures. The overall 1-year incidence of retreatment was 10.5%. The average length of time between initial treatment and enhancement was 7.3 +/- 6.4 months; 85% of retreatments took place within 1 year. Two hundred eighty-five of the 288 retreatments were accomplished using a manual flap lift approach; 3 eyes required a repeat microkeratome cut. Higher initial corrections and residual astigmatism were associated with a significantly higher rate of retreatment. Patients older than 40 years were at greater risk for retreatment. There was no gender difference. CONCLUSIONS Higher initial corrections, astigmatism, and older age are risk factors for LASIK retreatment. Most LASIK flaps can be lifted using the manual technique described up to 3 years after initial surgery.