Neodymium:yttrium-aluminum-garnet capsulotomy and intraocular pressure in pseudophakic patients with glaucoma.

OBJECTIVE: To determine the 1- and 3-hour changes in intraocular pressure after neodymium:yttrium-aluminum-garnet (Nd:YAG) capsulotomy in pseudophakic patients with glaucoma and to determine the effect of acetazolamide and apraclonidine on these changes.

DESIGN: Randomized controlled trial.

PARTICIPANTS: Pseudophakic patients with glaucoma requiring Nd:YAG posterior capsulotomy (n = 76).

INTERVENTION: Patients undergoing Nd:YAG posterior capsulotomy were randomly allocated to receive no therapy, oral acetazolamide (250 mg), or topical apraclonidine 1% within 1 hour before capsulotomy.

MAIN OUTCOME MEASURES: Intraocular pressures 1 and 3 hours after laser therapy were recorded.

RESULTS: Data were available for 76 eyes in 76 patients. Twenty-nine patients received no therapy; 24, oral acetazolamide; and 23, apraclonidine. One fifth (6/29) of patients with glaucoma developed a pressure rise of > or =5 mmHg if untreated, and 3% (1/29) developed a pressure rise of >10 mmHg. In comparison, no patients in the acetazolamide group developed a pressure rise of > or =5 mmHg (P = 0.02), and 1 of 24 in the apraclonidine group (P = 0.08) developed such a pressure rise, with none developing a pressure rise of >10 mmHg. When comparing all treated with nontreated, a reduction in the proportion with pressure rise was found (P = 0.01). All of the patients who developed a pressure rise of > or =5 mmHg did so within the first hour.

CONCLUSIONS: In the absence of therapy, clinically significant post-Nd:YAG pressure rises occur in one fifth of patients with glaucoma undergoing capsulotomy. Oral acetazolamide and topical apraclonidine reduce the frequency and magnitude of pressure rises and are of comparable effectiveness. In this study, all clinically important pressure rises developed within the first hour.