Prophylactic Use of Brimonidine for Intraocular Pressure Elevation after Nd: YAG Laser Posterior Capsulotomy

Cha, S C; Bae, S B; Lim, H S

Abstract

The purpose of this study was to evaluate the incidence and magnitude of intraocular pressure [IOP] spike following Nd: YAG laser posterior capsulotomy [YAG capsulotomy] in after-cataract patients with versus without glaucoma and to determine the prophylactic effect of brimonidine on IOP elevation as well as the risk factors of IOP spike after YAG capsulotomy. This prospective randomized study comprised 25 primary open angle glaucoma patients and 25 nonglaucomatous control patients undergoing YAG capsulotomy in one eye. A single drop of brimonidine tartrate or artificial tear was randomly instilled 20 minutes before YAG capsulotomy in a total of 50 patients. IOP was measured preoperatively and 1, 2 and 24 hours postoperatively. The incidence of IOP elevation lesser than 5 mmHg was 32.0% in glaucoma patients and 24.0% in control patients [p=0.67]; 9.1% in brimonidine prophylaxis group and 42.9% in control group [p=0.01], while that of IOP elevation of 5 mmHg or more at 1 hour following YAG capsulotomy was 8.0% in glaucoma patients and 4.0% in control patients [p=0.79]; 0% in brimonidine prophylaxis group and 1.7% in control group [p=0.05]. Multivariate logistic regression analysis identified lack of brimonidine prophylaxis, as the only clinically significant risk factor for IOP spike following YAG capsulotomy. Glaucoma patients in good IOP control after previous glaucoma surgery are at no greater risk for IOP spike following YAG capsulotomy than nonglaucomatous pseudophakic patients.Pre-laser brimonidine prophylaxis was beneficial in minimizing IOP spike following YAG capsulotomy in both glaucomatous and nonglaucomatous patients.