Effect of bimatoprost on intraocular pressure after cataract surgery

Background: An increase in intraocular pressure (IOP) frequently occurs after otherwise uneventful phacoemulsification cataract surgery. This study was conducted to determine the efficacy of bimatoprost 0.03% drops given preoperatively in preventing IOP rise following phacoemulsification cataract surgery.Methods: In this prospective, randomized, double-masked, placebo-controlled study, 91 eyes of 85 patients scheduled to have clear corneal phacoemulsification cataract surgery were randomly divided into 2 groups. One hour before surgery, 1 group (48 eyes) received 1 drop of bimatoprost 0.03%, and the other group (43 eyes) received 1 drop of a balanced saline solution (placebo). A masked observer measured IOP preoperatively, and 3 and 24 hours postoperatively. Anterior chamber cellular reaction was measured on the first day after surgery. Preoperative and postoperative central corneal thickness (CCT) was assessed.Results: The mean IOP changes from baseline were not statistically different between the 2 groups at 3 hours (p = 0.618). At 24 hours, there was a statistically significant difference between the mean IOP changes of the groups (p = 0.001). The incidence of IOP elevation greater than 5 or 10 mm Hg at 24 hours was significantly higher in the control group (9 of 43 eyes) than the bimatoprost group (3 of 48 eyes) (p = 0.039). Anterior chamber reaction was not increased by bimatoprost. Mean CCT change was not different between the groups at 24 hours (p = 0.615).Interpretation: When compared with placebo, prophylactic use of 1 drop of bimatoprost before phacoemulsification cataract surgery failed to produce a significantly different effect on IOP levels from placebo at 3 hours postoperatively, but it caused a significant IOP reduction at 24 hours.