Long-term outcomes of glaucoma drainage devices for glaucoma post-vitreoretinal surgery with silicone oil insertion: a prospective evaluation

Abstract

Purpose: To evaluate long-term success of the Ahmed glaucoma valve (AGV) for refractory glaucoma after vitreoretinal surgery with silicone oil insertion.

Methods: Prospective non-comparative evaluation of patients who underwent AGV insertion for management of post-vitreoretinal surgery glaucoma, post-silicone oil removal. Intraocular pressure (IOP), visual acuity, and glaucomatous neuropathy status were evaluated preoperatively and at multiple follow-up visits postoperatively. Success, using Kaplan-Meier analysis, was determined at the 12-month follow-up visit and at the last follow-up. Factors associated with failure were analysed.

Results: Twenty-seven eyes of 27 patients with a mean age of 28.3 ± 15.2 years underwent a superior AGV implantation. The average follow-up after AGV implantation was 17.11 ± 8.36 months (range: 9-60 months). Kaplan-Meier survival analysis revealed a 62 % success at 12 months and 37 % at 5 years. A 48 % rate of complications was noted, 22 % of which were vision-threatening. Factors analysed, including patient age, interval between vitreoretinal surgery and silicone oil removal, interval between vitreoretinal surgery and AGV implantation, and phakic status, were not found to be associated with higher failure rates.

Conclusion: Long-term success of AGV implantation for glaucoma after vitreoretinal surgery with silicone oil insertion is better than that reported for trabeculectomy, though complication rates remain high.

Keywords: Ahmed glaucoma valve; Glaucoma; Refractory glaucoma; Silicone oil; Vitreoretinal surgery.