Surgical treatment of strabismus secondary to glaucoma drainage device.

OBJECTIVE: To describe surgical strategies in a series of patients with diplopia following implantation of a glaucoma drainage device.
METHODS: Retrospective review of 9 consecutive patients who underwent strabismus surgery because of strabismus and diplopia after implantation of a glaucoma drainage device.
RESULTS: Seven patients with marked limitation to ocular rotations and incomitant strabismus underwent surgery on the eye with the implant. Two patients with mild limitation to ocular rotations of the involved eye underwent surgery on the contralateral eye. All patients had a large fibrous capsule surrounding the implant plate, adjacent muscles, and sclera. Intraocular pressure was not elevated postoperatively. Postoperative diplopia in the primary position was eliminated in 5 patients and markedly improved in 3 patients.
CONCLUSIONS: Strabismus following implantation of a glaucoma drainage device is an uncommon but serious complication. Restoration of ocular alignment is a complex undertaking requiring strabismus and glaucoma surgical expertise. Multiple surgical complications may occur. Surgical intervention may require complete removal of the fibrous capsule surrounding the implant and involved adjacent structures. Size reduction of the implant plate is helpful and did not interfere with postoperative intraocular pressure control in this study. Surgery on the contralateral eye is an option in patients with mild restriction.