Management of Ahmed glaucoma valve tube exposure after scleral patch graft shrinkage

BACKGROUND: Ahmed glaucoma valve (AGV) is an useful modality in the management of medically refractory glaucoma. Human donor scleral patch graft (SPG) can be employed to cover the external portion of the tube to prevent its exposure and associated sight-threatening complication. PURPOSE: To report the management of a case of AGV tube exposure due to SPG shrinkage in the right eye (RE) of a patient. SYNOPSIS: Under peribulbar anesthesia, the conjunctiva is undermined posteriorly, on either side of the exposed tube. The AGV tube is noted to lay firmly against the sclera without any excessive movement. The shrunk and displaced SPG is excised, and a larger, 6 × 8 mm, full-thickness, human donor SPG is placed on the episcleral bed, over the exposed segment of the tube, to ensure its adequate coverage. The SPG is sutured with four interrupted, 10-0 nylon sutures. The SPG is adequately covered with conjunctiva, by conjunctival mobilization and advancement to avoid excessive tension over the tube and closed with interrupted, 8-0 Vicryl suture. HIGHLIGHTS: SPG shrinkage and overlying conjunctival erosion can occur after AGV implantation. This can cause AGV tube exposure, which can be managed by donor SPG to cover the exposed tube. ONLINE VIDEO LINK: https://youtu.be/36Y0n22SxPU