Long-term results of non-valved Glaucoma drainage implant surgery and glaucoma drainage implant combined with trabeculectomy

PURPOSE: The purpose was to investigate the efficacy and complications of nonvalved glaucoma drainage implant (GDI) surgery and GDI combined with trabeculectomy. SUBJECTS AND METHODS: Serial Japanese patients who received GDI were retrospectively investigated. The survival rate of eyes was analyzed using the Kaplan-Meier method, defining death as: (1) Intraocular pressure (IOP) <6 mmHg, or ≥22 mmHg, and <20% reduction of preoperative IOP, (2) additional glaucoma surgery, (3) loss of light perception. Prognostic factors of age, sex, previous surgery, type of glaucoma, synechial closure, preoperative IOP, type of GDI (single-, double-plate Molteno, Baerveldt 350) and GDI combined with trabeculectomy were investigated employing proportional hazards analysis. RESULTS: One hundred and twenty-four eyes of 109 patients aged 53.3 ± 7.8 years old were analyzed. Types of GDI were single-plate (15.3%), double-plate Molteno (71.8%), and Baerveldt 350 (12.9%). The results of survival rate analysis were 86.1, 71.1, 71.1, and 64.6% for 1, 3, 5, and 10 years respectively. Thirty-four eyes (27.4%) died because of uncontrolled IOP (19.4%), loss of light perception (5.6%), and additional glaucoma surgery (2.4%). Single-plate Molteno was the only risk factor for failure. Persistent unphysiological hypotony (0.8%) and bullous keratopathy (5.6%) were observed. CONCLUSION: Nonvalved GDI surgery and GDI combined with trabeculectomy using nonabsorbable tube ligature proved to be an excellent device for any type of glaucoma in Japanese patients. Hypotony and corneal endothelial loss are the most serious complication in the long-term results of our patients.