RESUMEN
PURPOSE: To study the epidemiology and mid-term results of the Ahmed glaucoma valve (AGV) in various etiologies of refractory glaucoma in a Lebanese center, and to assess complications and factors that influence the surgical success rate. METHODS: In this retrospective epidemiological study, we reviewed 108 eyes with refractory glaucoma that underwent an AGV implantation in a tertiary care center in Lebanon between January 2002 and August 2014. Findings including best-corrected visual acuity (BCVA), intra-ocular pressure (IOP), number of antiglaucoma medications, factors influencing the surgical outcome, success rate and complications were also reviewed. RESULTS: The mean duration of follow-up was 29.85±21.45 months [range, 3-60 months]. As in other Arab countries and compared to the rest of the world, the rate of neovascular glaucoma (NVG) was particularly high, occurring in 63 eyes (58.3%), and represented the primary cause of refractory glaucoma. Mean IOP was significantly reduced to 17.97±7.35mmHg at the last follow-up visit (P<0.05). Similarly, a significant decrease was noted in the number of antiglaucoma medications (P<0.05). The surgical success rate, defined as a postoperative IOP<21, was significantly higher (62.0%), in older patients, those with baseline BCVA≤2 LogMAR and those with a history of hypertension (P<0.01). Hyphema was the most noted complication. CONCLUSION: The AGV is a safe and effective procedure for lowering IOP in refractory glaucoma patients, with hyphema being the most frequent complication. Both the presence of hyperstension and initial BCVA≤2 LogMAR seem to increase the success rate of the procedure. NVG remains the most common etiology for implantation, probably due to uncontrolled diabetes in the Middle East and North Africa.