Medical control of intraocular pressure after cataract surgery

To compare the effectiveness of 2 medications commonly used to prevent intraocular pressure (IOP) elevation in the early period after cataract surgery.

Palo Alto Veterans Affairs Health Care System, Palo Alto, California, USA.

This prospective study comprised 202 eyes of patients scheduled for cataract extraction who agreed to participate. Patients were randomized to receive oral acetazolamide, 500 mg 1 hour preoperatively; oral acetazolamide, 500 mg immediately postoperatively; apraclonidine hydrochloride 1%, 2 drops 1 hour preoperatively; or artificial tears (control group). Intraocular pressure was measured preoperatively and 4 to 6 and 24 hours postoperatively.

Preoperative IOP was not significantly different among the 4 groups. At 4 to 6 hours postoperatively, only preoperative acetazolamide was significantly more effective than the control medication (P = .038); at 24 hours there were no significant differences among the 4 groups. Postoperative IOP elevation in excess of 35 mm Hg at 6 or 24 hours decreased significantly in the preoperative acetazolamide group (3/46 eyes) compared with the control group (14/54 eyes). There was no statistically significant difference in IOP elevation between eyes having extracapsular cataract extraction and those having phacoemulsification, independent of treatment group.

The results favor preoperative acetazolamide to control postcataract IOP elevation. The method of cataract removal did not affect postoperative IOP elevation.