Randomized clinical trial of cryotherapy versus laser photocoagulation forretinopexy in conventional retinal detachment surgery

PURPOSE: To investigate whether the method of retinopexy influences the vis ual recovery rate and the breakdown of the blood-ocular barrier after conve ntional retinal detachment surgery. METHODS: Forty-eight patients (48 eyes) with primary rhegmatogenous retinal detachment entered into the study. All eyes were phakic, had an attached m acula, and were scheduled for conventional scleral buckling surgery. Patien ts were randomly assigned to have either laser or cryotherapy for retinopex y. All visual acuity and flare measurements were performed by a masked obse rver. The interventional procedure was cryopexy at the time of scleral buck ling surgery or postoperative (4 weeks) laser photocoagulation. Visual acui ty testing with ETDRS chart and aqueous flare measurement with laser flare photometry were performed by a masked observer at standard intervals: preop eratively and 1 day, 7 days, 4 weeks, and 10 weeks postoperatively. Analysi s of covariance by multiple linear regression was used for statistical eval uation. RESULTS: Postoperative flare values from patients receiving cryotherapy wer e significantly higher at each measurement point in time (P less than or eq ual to .001). The visual recovery was slower in the patients receiving cryo therapy (1 week, P = .003; 4 weeks, P = .03; 10 weeks, P = .081). CONCLUSION: Laser flare photometry proved sufficiently sensitive to quantif y an increase in aqueous flare after limited external retinal cryotherapy. Postoperative flare, as a measure of blood-ocular barrier breakdown, was si gnificantly higher and visual recovery slower in the cryotherapy group. Vis ual acuity after 10 weeks was not significantly different between both grou ps. (Am J Ophthalmol 2001;132:343-347. (C) 2001 by Elsevier Science Inc. Al l rights reserved.).