Intraindividual comparison of the effects of a fixed dorzolamide-timolol combination and latanoprost on intraocular pressure after small incision cataract surgery

Purpose: To compare the effect of a fixed dorzolamide-timolol combination with that of latanoprost on intraocular pressure (IOP) after small incision cataract surgery. Setting: Department of Ophthalmology, University of Vienna, Vienna, Austria. Methods: This prospective randomized study comprised 60 eyes of 30 patients scheduled for small incision cataract surgery in both eyes. The patients were randomly assigned to receive 1 drop of a fixed dorzolamide-timolol combination or latanoprost immediately after cataract surgery in the first eye. The second eye received the other antiglaucomatous agent. Cataract surgery was performed under sodium hyaluronate 1% with a temporal 3.5 mm sutureless posterior limbal incision, phacoemulsification, and implantation of a foldable intraocular lens. The IOP was measured preoperatively as well as 6 and 20 to 24 hours and 1 week postoperatively. Results: Six hours after surgery. the mean IOP decreased by -0.8 mm Hg +/- 3.2 (SD) (P = .184) in the dorzolamide-timolol group and increased by 3.6 mm Hg +/- 3.5 (P < .001) in the latanoprost group. Twenty to 24 hours after surgery, the mean IOP decreased by -2.8 +/- 2.4 mm Hg (P (.001) in the dorzolamide-timolol group and increased by 0.6 +/- 3.5 mm Hg (P = .353) in the latanoprost group. The differences between groups were significant at 6 hours (P < .001) and 20 to 24 hours (P < .001). Conclusions: The fixed dorzolamide-timolol combination was more effective than latanoprost in reducing IOP after small incision cataract surgery. Only the fixed dorzolamide-timolol combination prevented a postoperative IOP increase and occasional IOP spikes of 30 mm Hg or higher.