Probability of Nd : YAC laser capsulotomy after cataract surgery in Olmsted County, Minnesota

PURPOSE: To estimate the cumulative probability of Nd:YAG laser posterior c apsulotomy after cataract extraction in a geographically defined population . METHODS: Rochester Epidemiology Project databases were used to identify ret rospectively all Nd:YAG laser posterior capsulotomies performed on Olmsted County, Minnesota, residents who had previously undergone cataract extracti on between 1988 and 1996, inclusive. Demographic data and potential risk fa ctors for laser, including age, sex, surgical technique, year of surgery, a nd intraocular lens material, were obtained by chart review or by retrieval from computer databases. The cumulative probability of Nd:YAG laser poster ior capsulotomy was calculated by Kaplan-Meier estimates, and risk factors were analyzed using the Cox proportional hazards model. RESULTS: A total of 925 Nd:YAG laser posterior capsulotomies were identifie d after 3541 cataract extractions in 2718 patients. The cumulative probabil ity of Nd:YAG laser posterior capsulotomy after cataract surgery was 6% (95 % confidence interval = 5% to 7%) at 1 year, increasing to 38% (35% to 40%) at 9 years. Young age at the time of surgery (P = .02), polymethylmethacry late intraocular lens material (P < .001), earlier year of surgery (P < .00 1), and extracapsular extraction (in comparison with phacoemulsification, P < .001) were found to increase significantly the risk of subsequent Nd:YAG laser posterior capsulotomy. Woman tended to have a greater probability of Nd:YAG laser posterior capsulotomy (P = .17), but this difference was not statistically significant. CONCLUSIONS: Nd:YAG laser posterior capsulotomy was common after cataract s urgery but infrequent during the first postoperative year. Prolonged follow -up is necessary in investigations of the effects of new cataract surgery t echnologies on the probability of capsulotomy, (Am J Ophthalmol 2001;131:16 1-166. (C) 2001 by Elsevier Science Inc. All rights reserved).