Objective: To compare the effectiveness of argon laser trabeculoplasty (ALT) and selective laser trabeculoplasty (SLT) in lowering intraocular pressure (IOP) in younger patients (age 60 or less).
Methods: This was a prospective randomized control trial. Forty-two young patients (age 29 to 60 y) had 1 eye randomized to ALT (n=22) or SLT (n=20). IOP was measured before laser and 1 hour, 1 day, 6 weeks, 3 months, every 3 months until 2 years, and then yearly postlaser. Chi-square analysis and Student t test were used to determine statistical significance.
Results: The mean IOP before treatment was 21.9 mm Hg for ALT and 19.1 mm Hg for SLT with no statistical difference between the groups (P>0.05). At 2 years, 86.4% of ALT and 75.0% of SLT eyes required no further surgical intervention (laser trabeculoplasty or trabeculectomy). During the same time period, there was a statistically significant IOP decrease of 11.1% after ALT (P=0.01) and 7.7% after SLT (P=0.01) with no statistical difference between the lasers (P>0.05).
Conclusions: In younger patients, both ALT and SLT have a significant ocular hypotensive effect 2 years after treatment, with no differences in outcome identified between the laser modalities.