The Ex-PRESS glaucoma shunt versus trabeculectomy in open-angle glaucoma: a prospective randomized study

The purpose of this study was to establish the efficacy and safety of the Ex-PRESS (Optonol Ltd., Neve Ilan, Israel) mini glaucoma shunt in open-angle glaucoma. This was a prospective, randomized trial. Eyes from enrolled patients were randomly assigned to either Ex-PRESS implantation under a scleral flap, or trabeculectomy. The main outcome measures were: mean intraocular pressure (IOP), postoperative medication use, visual acuity, and incidence of complications. Complete success was defined as an IOP of > 4 mmHg and a parts per thousand currency sign18 mmHg without the use of antiglaucoma medications. A more stringent target of IOP > 4 mmHg and a parts per thousand currency sign15 mmHg was also noted. There were 78 patients (80 eyes) with primary open-angle, pseudoexfoliative, or pigmentary glaucoma enrolled in the study. A total of 84.6% of patients receiving Ex-PRESS and 60.0% of patients receiving trabeculectomy (P=0.0230) achieved complete success. The respective proportions of patients achieving an IOP > 4 mmHg and a parts per thousand currency sign15 mmHg were 76.9% and 50.0% (P=0.0193). At 1-year follow-up, complete success rates were 81.8% for Ex-PRESS and 47.5% for trabeculectomy (P=0.0020), and 71.7% and 37.5% (P=0.0070), respectively, for the more stringent target. There was a similar level of postoperative interventions and complications for each group. In open-angle glaucoma, the Ex-PRESS mini glaucoma shunt implanted under a superficial scleral flap produces significantly higher success rates, and a similar complication rate, compared with trabeculectomy. The Ex-PRESS is a safe and effective device for treating open-angle glaucoma.