Long-Term Outcome of Ahmed Valve Implantation Combined with 23-Gauge Vitrectomy in Eyes with Neovascular Glaucoma

ABSTRACT

PURPOSE: To investigate the surgical outcome of Ahmed glaucoma valve implantation (AVI) combined with 23-gauge vitrectomy in eyes with medically uncontrolled neovascular glaucoma (NVG). METHODS: Thirty six eyes of 35 NVG patients who underwent AVI combined with 23-gauge vitrectomy and have been followed-up at least 6 months after surgery and were retrospectively reviewed. Surgical success was defined as the control of intraocular pressure (IOP) between 6 and 21 mm Hg, irrespective of the use of topical IOP lowering medications. Surgical failure was defined as the failure of IOP control or visual acuity aggravated to no light perception after the surgery. Overall success rate, median survival time, and clinical factors associated with survival time were investigated. RESULTS: The overall success rate was 63.2% after a mean of 34.0 ± 31.7 months postoperative follow-up. The success rate was 83.3% at postoperative 6 months, 72.7% at postoperative 12 months and 63.2% at postoperative 3 years. The underlying retinal diseases were proliferative diabetic retinopathy (PDR; n = 20, 55.5%), central retinal vein occlusion (CRVO; n = 12, 33.3%), ocular ischemic syndrome (n = 2, 5.6%), and other retinal vascular diseases (n = 2, 5.6%). The survival times were significantly shorter in eyes with CRVO (20.2 ± 30.5 months) compared to PDR (33.1 ± 30.8 months), and in phakic eyes (33.1 ± 30.8 months) compared to pseudophakic eyes (37.7 ± 35.4 months) (p < 0.05). In the multivariate analysis, preoperative phakic eyes were significantly associated with a shorter survival time (hazard ratio = 5.626, p = 0.030). CONCLUSIONS: Combined surgery of Ahmed glaucoma valve implantation and 23-gauge vitrectomy showed favorable outcome in the treatment of medically uncontrolled NVG. Preoperative lens status may affect the long-term success rate in such patients.