The Experience of Ahmed Glaucoma Valve Implantation in Patients with Intractable Glaucoma

Purpose: To report the clinical experience of intraocular pressure (IOP) lowering effect of Ahmed Glaucoma Valve implant on patients with intractable glaucoma. Methods: Twenty eyes (20 patients) with intractable glaucoma treated with the Ahmed Glaucoma Valve implants were enrolled in this study. The mean follow-up time was 12.2±0.8 months. The mean age was 54.2±1.8 years. Surgical success was defined as lop less than 22 mmHg and greater than 5 mmHg without additional glaucoma surgery. Postoperative use of antiglaucoma medications was not a criterion for success or failure. All patients received detail ophthalmic examination including slit lamp, IOP, and visual acuity with best correction in preoperative and postoperative periods. The difference in variables before and after Ahmed Glaucoma Valve implant surgery was compared by paired t-test. Results: The mean lop was reduced from 41.1±11.1 mmHg before surgery to 16.4±5.8 mmHg at the last follow-up after surgery (P＜0.001). The number of antiglaucoma medications was decreased from preoperative 2.7±1.2 to 0.3±0.2 after surgery (P＜0.01). The visual acuity was improved or within one Snellen line in 19 eyes (95%). Although complications occurred in 13 eyes, the majority of which did not affect surgical outcome. The success rate by our definition was 95%. Conclusion: The Ahmed Glaucoma Valve implant is effective in lowering IOP in patients with intractable glaucoma. Postoperative hypotony, as frequently encountered in other non-valve drainage implants, is not common with this implant. From our study, it revealed that the Ahmed Glaucoma Valve implant provides an alternative ways to control IOP in patients with intractable glaucoma in intermediate term follow-up.