Prospective Randomized Study Comparing Ex-PRESS to Trabeculectomy

Abstract

To compare the efficacy and safety of the Ex-PRESS glaucoma shunt with standard trabeculectomy. Consenting patients with medically uncontrolled open-angle glaucoma were prospectively randomized to trabeculectomy or Ex-PRESS shunt both with mitomycin-C. Exclusion criteria included previous ocular surgery with the exception of clear cornea phaco or 1 previous trabeculectomy, uveitis, and vitreous in the anterior chamber. Standardized data collection sheets were completed at baseline and postoperative day 1, weeks 1 and 2, and months 1, 2, 3, 6, and 12. Primary outcome was intraocular pressure (IOP). Complete success was defined as an IOP between 5 and 18 mm Hg and a 20% reduction from baseline without medication. A sample size calculation determined that 52 eyes were required to detect a 2.0 mm Hg IOP difference with a power of 80%. Sixty-four subjects were enrolled, 33 in the Ex-PRESS and 31 in the trabeculectomy group. IOP was not statistically significantly different between groups. Baseline and 1-year mean IOP was 22.0±6.8 versus 22.7±10.3 mm Hg (P=0.76) and 11.6±4.5 versus 11.3±4.5 mm Hg (P=0.81) in the trabeculectomy versus Ex-PRESS groups, respectively. Complete success was 57% versus 70% (P=0.28) in the trabeculectomy versus Ex-PRESS groups, respectively. There were no statistically significant differences in surgical time, number of glaucoma medications, visual acuity, central corneal thickness, endothelial cell counts, complications, interventions, or bleb morphology between the trabeculectomy and the Ex-PRESS groups. There was no statistically significant difference between the trabeculectomy and Ex-PRESS groups regarding IOP, success rates, complications, additional interventions, and bleb morphology.