Comparison of trabeculectomy and Ex-PRESS implantation in fellow eyes of the same patient: a prospective, randomised study

Purpose To compare intraocular pressure (IOP) over time after standard trabeculectomy vs Ex-PRESS implantation in patients with bilateral primary open-angle glaucoma (POAG). Design Prospective, randomised study. Patients and methods This study included adult patients with bilateral POAG necessitating surgery. Each patient underwent trabeculectomy in one eye and Ex-PRESS implantation under a scleral flap in the other eye according to randomised contralateral allocations. Efficacy was assessed by IOP values and success rates (IOP threshold and/or need for topical glaucoma medication) during 30 months. Statistical analysis included Generalised Estimate Equation and Cox Survival models, and paired t-tests. Results Thirty eyes of 15 patients were studied for a mean of 23.6 months (SD, +/- 6.9). At the last follow-up visit, mean pre-operative IOP decreased from 31.1 (+/- 14.2) to 16.2 (+/- 1.5) mmHg after trabeculectomy, and from 28.1 (+/- 9.0) to 15.7 (+/- 1.8) mmHg after Ex-PRESS implantation (P = 0.001). The mean number of anti-glaucoma medicines prescribed at the last follow-up decreased from 3.7 pre-operatively (both groups) to 0.9 after trabeculectomy vs 0.3 after Ex-PRESS implantation (P 0.001). Complete success rates (5<IOP<18 mm Hg without medications) were higher with Ex-PRESS compared with trabeculectomy (P = 0.0024). Postoperative complications were more frequent after trabeculectomy (33%) compared with Ex-PRESS (20%), with four trabeculectomy eyes (27%) needing postoperative interventions, compared with none with Ex-PRESS. Conclusions Trabeculectomy and Ex-PRESS implantation provided similar IOP control, but the Ex-PRESS group had a lower rate of complications, fewer postoperative interventions, and needed less glaucoma medications. Eye (2012) 26, 703-710; doi: 10.1038/eye.2012.13; published online 17 February 2012