Purpose: To compare outcomes of selective laser trabeculoplasty (SLT) with drug therapy for glaucoma patients in a prospective randomized clinical trial.
Patients and methods: Sixty-nine patients (127 eyes) with open-angle glaucoma or ocular hypertension were randomized to SLT or medical therapy. Target intraocular pressure (IOP) was determined using the Collaborative Initial Glaucoma Treatment Study formula. Patients were treated with SLT (100 applications 360 degrees) or medical therapy (prostaglandin analog). Six visits over 1 year followed initial treatment. If target IOP range was not attained with SLT, additional SLT was the next step, or in the medical arm additional medications were added.
Primary outcome: IOP; secondary: number of steps.
Results: Sixty-nine patients were treated. Data collection terminated with 54 patients reaching 9 to 12-months follow-up. Twenty-nine patients were in the SLT group, 25 patients in the medical group. Baseline mean IOP for all eyes was 24.5 mm Hg in the SLT group, 24.7 mm Hg in the medical group. Mean IOP (both eyes) at last follow-up was 18.2 mm Hg (6.3 mm Hg reduction) in the SLT arm, 17.7 mm Hg (7.0 mm Hg reduction) in the medical arm. By last follow-up, 11% of eyes received additional SLT, 27% required additional medication. There was not a statistically significant difference between the SLT and medication groups.
Conclusions: IOP reduction was similar in both arms after 9 to 12-months follow-up. More treatment steps were necessary to maintain target IOP in the medication group, although there was not a statistically significant difference between groups. These results support the option of SLT as a safe and effective initial therapy in open-angle glaucoma or ocular hypertension.