Short-Term Results of Ahmed Glaucoma Valve Implantation in Refractory Glaucoma

Abstract

Objective: The aim of this study was to evaluate short-term outcomes of Ahmed glaucoma valve (AGV) (New World Medical Inc., Rancho Cucamonga, CA, USA) implantation in cases of refractory glaucoma. Methods: The records of 31 patients who underwent AGV implantation between January 2018 and March 2019 for refractory glaucoma were retrospectively evaluated. Patients with a visual acuity of at least light perception and postoperative follow-up records of at least 6 months were included in the study. Preoperative and postoperative best corrected visual acuity (BCVA), intraocular pressure (IOP), number of topical antiglaucoma medications used, and central corneal thickness (CCT) measurements were recorded, as well as any postoperative complications. Results: The surgical outcome was graded as complete success for an IOP of 5 to 22 mmHg without antiglaucomatous medication, qualified success for an IOP of 5 to 2 mmHg with antiglaucomatous medication, or failure for an IOP >22 mmHg despite medication. The sum of the complete success and qualified success groups was considered the total success rate. The mean length of follow-up was 12.94±4.98 months. The preoperative mean IOP level and number of topical antiglaucoma medications had decreased from 40.84±8.27 mmHg to 13.84±2.95 mmHg and 3.68±0.54 to 1.10±1.35, respectively, at the final postoperative examination. There were no significant differences between the preoperative and postoperative CCT and BCVA values (p>0.05). The most common (n=3) complication was encapsulated cyst formation in the AGV plate region. The complete, qualified, and total success rates were 45.2% (n=14), 54.8% (n=17) and 100% (n=31), respectively. Conclusion: Although the mean preoperative IOP level is typically quite high in refractory glaucoma cases, AGV implantation is an effective surgery for reducing IOP in the short term. Longer follow up will show the sustainable impact of AGV implantation on IOP.