Efficacy of long scleral tunnel technique in preventing Ahmed glaucoma valve tube exposure through conjunctiva

Abstract

Purpose: To evaluate the efficacy of long scleral tunnel technique used in Ahmed glaucoma valve (AGV) implantation in preventing tube exposure through conjunctiva.

Materials and methods: Patients of adult age, who were unresponsive to maximum medical treatment and underwent AGV implantation, were divided into two groups and investigated retrospectively. Group 1 consisted of 40 eyes of 38 patients that underwent surgery by long scleral tunnel technique and Group 2 consisted of 38 eyes of 35 patients that underwent implantation by processed pericardium patch graft method.

Results: The mean age was 54.8 ± 14.6 years (range 26-68 years) and the mean follow-up duration was 46.7 ± 19.4 months (range 18-76 months) for the patients in Group 1, whereas the mean age was 58.6 ± 16.7 years (range 32-74 years) and mean follow-up period was 43.6 ± 15.7 months (range 20-72 months) for the patients in Group 2 (p > 0.05). In the course of follow-up, tube exposure was detected in one (2.5%) eye in Group 1 and in three (7.9%) eyes in Group 2 (p = 0.042).

Conclusion: Long scleral tunnel technique is beneficial in preventing conjunctival tube exposure in AGV implantation surgery.

Keywords: Ahmed glaucoma valve; glaucoma drainage device; pericardium patch graft; scleral tunnel; tube exposure.