Surgical Outcomes of a Second Ahmed Glaucoma Valve Implant for the Treatment of Refractory Glaucoma.

Abstract

To evaluate the surgical outcomes of a second AGV implant in Hispanic patients with refractory glaucoma. The medical records of patients who underwent a second AGV implant were reviewed retrospectively. Clinical outcome measures including intraocular pressure (IOP), visual acuity, and glaucoma medication use were collected from the preoperative visit and all follow-up visits up to 18 months after surgery. Failure was defined as one of the following: loss of light perception, sustained IOP >21 or <6 mm Hg, an IOP reduction of <20% from baseline, need for additional glaucoma surgery, including needling revision with subconjunctival adjuvant therapy, or valve extrusion. A total of 48 patients were included. In all cases, an S-2 model was implanted in the superonasal quadrant. Mean preoperative IOP was 24.3±7.9 mm Hg and was significantly reduced to 13.9±4.8 at 6 months (P<0.05), 15.4±7.2 at 12 months (P<0.05), and 12.9±2.0 at 18 months (P<0.05). Mean glaucoma medications were reduced from 2.8±1.1 preoperatively to 1.9±1.2 at 6 months (P<0.05), 2.4±1.2 at 12 months, and 2.2±1.1 at 18 months; however, the difference was no longer statistically significant after 6 months, and the success rate was 60% at the mean for survival time of 15 months (13.7 to 16.5). The findings of this study demonstrate that a second AGV can achieve a significant reduction in IOP for up to 18 months postoperatively.