the incidence, concurrent factors and clinical results of reoperation after corneal refractive surgeries

purpose: to determine the incidence, concurrent factors and clinical results of re-operation after corneal refractive surgeries. methods: in this retrospective descriptive study records of all patients undergoing corneal refractive surgeries including prk, lasik, and lasek between april 2005 and december 2006 were assessed. patients who had undergone re-operations entered the study; visual acuity with and without correction, and refraction before and after the operation were analyzed. results: out of 10,311 eyes of 5,257 patients, 63 eyes (0.6%) underwent one or more re-operations. the mean duration between the first and second operation was 116±20 days. mean±sd spherical equivalent refractive error before the first operation in re-operated eyes was -4.40±3.17 d (ranging from -14.25 to +5.88 d), -4.58±3.25 d (ranging from -14.25 to +5.18 d) in the lasik group, and -2.73 to±1.61 d (ranging from -5.13 to 0.8 d) in the prk group. mean±sd of spherical equivalent refractive error of these patients before re-operation was -1.13±1.97 d (ranging from -4.25 to +3 d). this mean value was -1.25±1.71 d (ranging from -4.25 to +3.00 d) and -0.45±1.7 d (ranging from -2.75 to +1.5 d) in the lasik and prk groups respectively. before re-operation, only 30% of re-operation candidates had visual acuity of 20/40 or better while all of them reached this level of visual acuity after re-operation. conclusion: laser corneal refractive re-operation can be a safe and efficient alternative for treatment of residual refractive errors after previous photorefractive surgery and the low prevalence and incidence of re-operation among iranian patients can be a sign of suitable nomograms used in patients of iranian descent.