Randomised fellow eye comparison of the effectiveness of dorzolamide and apraclonidine on intraocular pressure following phacoemulsification cataractsurgery

Purpose To compare the effectiveness of 2% dorzolamide and 0.5% apraclonidi ne on intraocular pressure (IOP) following phacoemulsification cataract sur gery. Methods This prospective, randomised study comprised 54 eyes of 27 consecut ive patients with age-related cataract scheduled for cataract surgery in bo th eyes. In each patient the eye with the higher degree of cataract was ran domly assigned to receive one drop of either dorzolamide or apraclonidine i mmediately after surgery. The fellow eye was operated on later and received the other treatment. Cataract surgery was performed with a superior 6.0 mm sutureless frown incision, phacoemulsification and implantation of a three -piece PMMA intraocular lens. The IOP was measured preoperatively as well a s 6 h and 20-24 h and 1 week post-operatively. Results The mean pre-operative IOP was not significantly different between the groups (dorzolamide group, 14.9 +/- 2.3 mmHg; apraclonidine group, 14.6 +/- 2.5 mmHg; p = 0.450). At 6 h post-operatively, the mean IOP was signif icantly lower in the dorzolamide than in the apraclonidine group (15.6 +/- 3.9 mmHg vs 18.0 +/- 4.0 mmHg; p < 0.001). An IOP increase of more than 5 m mHg at 6 h post-operatively occurred in 3 (12%) eyes in the dorzolamide gro up and in 9 (36%) eyes in the apraclonidine group (p = 0.034). At 20-24 h p ost-operatively and at 1 week post-operatively no difference was found betw een the groups. Conclusions 2% Dorzolamide is more effective than 0.5% apraclonidine in pre venting the early post-operative IOP increase following phacoemulsification cataract surgery.