Effect of dorzolamide and latanoprost on intraocular pressure after small incision cataract surgery

PURPOSE: To evaluate the effect of dorzolamide 2% and latanoprost 0.005% on intraocular pressure (IOP) after small incision cataract surgery. SETTING: Department of Ophthalmology, University of Vienna, Vienna, Austria. METHODS: This prospective study comprised 102 eyes of 102 consecutive patients scheduled for small incision cataract surgery. The patients were assigned preoperatively to 1 of 3 groups of 34 each: dorzolamide, latanoprost, and control (no treatment). One drop of the assigned medication was instilled immediately after surgery. Intraocular pressure was measured preoperatively and 6 and 20 to 24 hours postoperatively. RESULTS: Six hours after surgery, the mean increase in IOP was 1.9 mm Hg +/- 3.9 (SD) in the dorzolamide group (P = .004 versus control), 2.2 +/- 3.0 mm Hg in the latanoprost group (P = .005 versus control), and 4.8 +/- 5.2 mm Hg in the control group. Twenty to 24 hours postoperatively, IOP decreased a mean of -0.9 +/- 3.5 mm Hg in the dorzolamide group (P = .012 versus control) and increased a mean of 0.3 +/- 3.6 mm Hg in the latanoprost group (P = 0.24 versus control) and 1.3 +/- 4.2 mm Hg in the control group. One eye in the dorzolamide group, 1 eye in the latanoprost group, and 4 eyes in the control group had an IOP of 30 mm Hg or higher 6 hours postoperatively. CONCLUSION: Six hours postoperatively, dorzolamide and latanoprost were effective in reducing the IOP increase after small incision cataract surgery; however, at 20 to 24 hours, only dorzolamide was effective. Neither drug prevented IOP spikes of 30 mm Hg or higher.