Two Year Randomized Prospective Comparison of Ahmed Valve Versus Baerveldt Implant in Vitrectomized Eyes

Abstract

Précis: Ahmed Valve and Baerveldt shunt are efficacious options in vitrectomized eyes. Baerveldt implant achieves a lower mean intraocular pressure (IOP) at 2 years, with fewer medications and a higher percentage of medication-free patients.Purpose: To investigate and compare the efficacy and complications between Ahmed FP7 Glaucoma Valve (AGV) and Baerveldt 101-350 Glaucoma Implant (BGI) in vitrectomized eyes. Materials and Methods:In this single-center randomized clinical trial, 43 vitrectomized eyes (39 patients) underwent glaucoma drainage device implantation. Eyes were randomized to receive either an AGV (FP7) or a BGI (101-350) and were followed for 2 years. Surgical success was defined as an IOP measurement ≤ 18 mm Hg and ≥ 5 mm Hg with or without glaucoma medication at 2 or more sequential visits after 3 months. The primary outcome was the comparison of the success rate at 2 years, while mean IOP, mean number of medications, and number of complications were considered secondary outcomes.Results: Kaplan-Meier estimates of the 2-year success rates in IOP control after GDD implantation were similar between the 2 groups; AGV group 81.8% (95% CI: 67.2%-99.6%) and BGI group 85.7% (95% CI: 72.0%-100.0%), (log-rank test P value = 0.74). Patients in the BGI group had a statistically significant lower mean IOP compared with the AGV group in all follow-up visits at 2, 6, 12, and 24 months (11.62 vs. 17.45 mm Hg at the latter P value <0.001). The BGI group required a significantly lower number of medications for IOP control at the 2-year visit compared with the AGV group (0.76 ± 0.99 vs. 1.5 ± 1.06 P value = 0.02) but had a higher number of complications (62% vs. 41%, respectively).Conclusions: GDDs provide a viable solution for IOP control in vitrectomized eyes. Based on our prospective comparison, both Ahmed FP7 Glaucoma Valve and Baerveldt 101-350 Glaucoma Implant are efficacious options.

Factors Affecting the Results of Ahmed Glaucoma Valve Implantation in Diabetic Neovascular Glaucoma With or Without Previous Pars Plana Vitrectomy

“…Many published studies have reported the effectiveness and safety of AGVI in vitrectomized eyes with different indications for PPV (17)(18)(19)(20)(21). However, AGVI results may vary depending on etiology.…”