Management of implant plate exposure of silicone Ahmed glaucoma valve: a review of six cases

To describe the management options for exposed silicone Ahmed glaucoma valve (AGV) implant. This was carried out as a retrospective chart review at a tertiary care eye hospital in Southern India. Medical records of six subjects managed for AGV exposure from 2006 to 2013 were reviewed. All six eyes had explantation of the AGV and 3 of them had reimplantation in a different quadrant at a later date and the other 3 eyes were managed medically. All eyes had well controlled IOP at the last follow-up. The possible predisposing factors for exposure were improper conjunctival coverage, higher number of pre shunt surgeries and diabetes mellitus. Reimplantation was a challenge with scarred conjunctiva and the techniques used were conjunctival advancement, conjunctival relaxing incisions and contralateral conjunctival autograft. None had re-exposure but one eye had conjunctival erosion close to the limbus and was managed with scleral patch graft and conjunctival advancement. Implant exposure is a serious vision threatening complication following glaucoma drainage device implantation. Explantation and timely repair can save these eyes from serious sequel. Reimplantation is a good option, however warrants close follow-up for complications like erosion or re-exposure.