Incidence and Management of Encapsulated Cysts Following Ahmed Glaucoma Valve Insertion

PURPOSE: Encapsulated cysts have been inconsistently reported to occur following Ahmed glaucoma valve implant insertion. We are unaware of previous reports reviewing their management. The objective of this study was to evaluate the occurrence and management of encapsulated cyst formation following Ahmed glaucoma valve implant insertion. PATIENTS AND METHODS: Consecutive glaucoma patients who underwent Ahmed glaucoma valve implant insertion were studied retrospectively. Inclusion criteria included a minimum of 12 months of follow-up. RESULTS: Fifty-seven patients met inclusion criteria for analysis. Following Ahmed glaucoma valve implant insertion, 13 patients (23%) developed an encapsulated cyst. After failing medical therapy and needling with 5-fluorouracil, 11 of these patients underwent surgical excision to control intraocular pressure. Eight of the eleven patients achieved adequate control of intraocular pressure with a mean follow-up time post excision of 330 +/- 120 days. CONCLUSION: Encapsulated cysts associated with elevated intraocular pressure were commonly seen after Ahmed glaucoma valve implant insertion. Failing medical therapy, surgical excision of the cyst is effective in lowering intraocular pressure.