Effect of topical prostaglandin analog use on outcome following selective laser trabeculoplasty

The aim of this study was to determine the effect of prostaglandin analog use on postoperative intraocular pressure (IOP) and treatment success following selective laser trabeculoplasty (SLT).

Records from 113 eyes with open angle glaucoma who underwent SLT were reviewed retrospectively. Eyes were categorized as to whether they were receiving a topical prostaglandin analog (n = 78) or other classes of glaucoma medications (n = 35) before and following SLT. IOP was measured before (baseline) and at 1 h, 1 day, 1 week, and 1 month following SLT.

Baseline IOP (+/-standard error [SE]) did not differ between prostaglandin analog users (18.0 +/- 0.48 mmHg) and nonusers (17.5 +/- 0.71 mmHg). One (1) month after SLT, average IOP decrease (+/-SE) was greater (P < 0.02) among prostaglandin analog users (3.4 +/- 0.4 mmHg), compared to nonusers (1.6 +/- 0.5 mmHg). Also at 1 month, average percent IOP decrease (+/- SE) was greater (P < 0.015) among prostaglandin analog users (16.5 +/- 2.0%), compared to nonusers (7.9 +/- 2.7%). At 1 h, 1 day, and 1 week after SLT, there were no differences in average IOP decrease or percent IOP decrease between prostaglandin analog users and nonusers. The percentage of eyes with a 20% or greater decrease in IOP was greater (P < 0.015) among prostaglandin analog users (44.9%), compared to nonusers (22.9%), 1 month after SLT. Also, 48.7% of prostaglandin analog users had an IOP decrease of 3 mmHg or greater, compared to 31.4% of nonusers, 1 month after SLT (P < 0.05). Retreatment rate among prostaglandin analog users (11.5%) was less (P < 0.005) than nonusers (34.3%).

Prostaglandin analog use during the perioperative period prior to and 1 month after SLT is associated with greater average IOP decrease and percent IOP decrease 1 month postoperatively, compared to eyes not receiving these agents. Prostaglandin analog use is also associated with a greater likelihood of treatment success and a lesser likelihood of requiring retreatment 1 month postoperatively.