A topical or oral carbonic anhydrase inhibitor to control ocular hypertension after cataract surgery

PURPOSE: To compare the effects of oral acetozolamide and topical 2% dorzolamide to prevent ocular hypertension after cataract surgery. METHODS: This prospective, randomized study comprised 62 consecutive patients who had extracapsular cataract extraction and posterior chamber intraocular lens implantation. Patients received either oral acetozolamide (Diazomide) 250 mg three times daily or topical dorzolamide 2% (Trusopt) three times daily, for three days. Intraocular pressures (IOP) were measured by Goldmann applanation tonometry preoperatively and 16, 40, 64 hours postoperatively. RESULTS: IOP in the dorzolamide group peaked at 16 hours and had returned to preoperative values by 40 hours. In the acetozolamide group mean IOP was significantly higher than preoperative values at 16, 40 and 64 hours (p<0.05). At all three postoperative measurement times, mean IOP was significantly higher in the acetozolamide group (p<0.05). CONCLUSIONS: Topical dorzolamide 2% offers better IOP control than oral acetozolamide to prevent ocular hypertension after cataract surgery.