The Effect of 0.25% Apraclonidine in Preventing Intraocular Pressure Elevation After Nd:yag Laser Posterior Capsulotomy

Abstract

Purpose. The efficacy and adverse effects of 0.25% apraclonidine on intraocular pressure (IOP) after Nd: YAG laser posterior capsulotomy were investigated, and the results were compared with placebo, 0.50% timolol maleate and 1% apraclonidine. Methods. Eighty eyes were randomly assigned to four groups of 20 eyes. In a double-masked design, the groups were treated with placebo (group I), 0.50% timolol maleate (group 2), 1% apraclonidine (group 3), 0.25% apraclonidine (group 4) one hour before and five minutes after Nd:YAG laser posterior capsulotomy. IOP was measured by applanation tonometry I hour before (baseline IOP) and 1, 3, 24 hours after capsulotomy. Results. The average baseline IOP increased respectively 3.90 +/- 5.35, 5.95 +/- 5.32, 1.15 +/- 3.20 mmHg in the first group 1, 3 and 24 hours post-treatment. There were significant differences between baseline IOP and 1 and 3 hours but not at 24 hours (p=0.004, p=0.001, p=0.13). IOP increased 0.40 +/- 4.08, 0.75 +/- 5.33, 0.80 +/- 6.03 mmHg in the second group at the same times. The differences between the average baseline IOP and the 1, 3 and 24 h measurement were not significant (p=0.83, p=0.65, p=0.93). In the third group, IOP decreased 3.70 +/- 2.40, 3.30 +/- 2.47, 2.65 +/- 1.56 mmHg at the measurement times, with significant differences between the average baseline IOP and the 1, 3 and 24 hour measurements (p=0.001, p=0.0001, p=0.01). In the fourth group IOP increased 0.35 +/- 3.32 mmHg at 1 hour, but decreased 1.25 +/- 3.41, 0.90 +/- 2. 07 mmHg at 3 and 24 hours. The differences were not significant (p = 0.94, p = 0.16, p = 0.08). When the 0.25% and 1% apraclonidine groups were compared, there were significant differences between the average IOP at 1 hour in both groups but not at 3 and 24 hours (p=0.01, p = 0.17, p = 0.21). Similarly, there were no significant differences between the average IOP at the same times when the 0.25% apraclonidine group was compared with the timolol group (p = 0.30, p = 0.08, p = 0.16). Some systemic and local side effects were seen in the timolol and 1% apraclonidine groups, but none with 0.25% apraclonidine. Conclusions. It was concluded that 0.25% apraclonidine is effective in preventing the early elevation of IOP after Nd:YAG laser posterior capsulotomy and may offer an alternative to 0.50% timolol maleate and 1% apraclonidine.