A comparison of the intraocular pressure lowering effect of adjustable suture versus laser suture lysis for trabeculectomy.

PURPOSE: To compare the intraocular pressure lowering effect of adjustable sutures and laser suture lysis for trabeculectomy in eyes with primary open angle glaucoma. METHODS: Fifty patients with primary open angle glaucoma were studied. Eyes were assigned randomly to either trabeculectomy augmented with mitomycin C with adjustable sutures or with laser suture lysis. Patients were followed up for 12 months and success rate based on intraocular pressure was compared. Adjustable sutures were carried out as reported by Wells et al. RESULTS: Mean baseline intraocular pressure was 27.8±2.8 mm Hg in the adjustable suture group and 27.3±2.9 mm Hg in the laser suture lysis group (P=0.7). Mean postoperative intraocular pressure was 12.1±2.0 mm Hg at 3 months, 12.7±3.2 mm Hg at 6 months, and 12.9±3.4 mm Hg at 12 months in the adjustable suture group and 12.1±2.6 mm Hg at 3 months, 13.1±4.7 mm Hg at 6 months, and 13.4±3.5 mm Hg at 12 months in the laser suture lysis group. There was no significant difference in the mean intraocular pressure between the groups at any time point. At 12 months, 24 patients (96%) in the adjustable suture group and 23 patients (92%) in the laser suture lysis group achieved an intraocular pressure of ≥20 mm Hg without medication and a minimum of 30 percent reduction (P=0.7). Significant anterior chamber reduction was found in no patient (0%) in the adjustable suture group and 6 patients (24%) in the laser suture lysis group after loosening of the adjustable sutures or laser suture lysis. CONCLUSIONS: There was no significant difference in hypotensive efficacy between adjustable suture group and laser suture lysis group. The use of adjustable sutures may reduce the incidence of shallow anterior chamber and hypotony after postoperative intraocular pressure lowering procedures.