Persistent leak after glaucoma aqueous shunt implantation.

Purpose

To present 4 cases of persistent leak attributed to subconjunctival fistula formation after glaucoma aqueous shunt implantation. Our preferred method for management is also described.

Methods

Retrospective noncomparative case series.

Results

Four cases of persistent leak after glaucoma aqueous shunt surgery are described. Three patients had an underlying diagnosis of iridocorneal endothelial syndrome and 1 patient had a diagnosis of chronic panuveitis. Three patients had prior trabeculectomy with adjunctive periocular application of antiproliferative agents (mitomycin C and/or 5-fluorouracil). One patient had aqueous shunt implantation as a primary glaucoma procedure. Implantation of the Molteno (1 patient), Ahmed (2 patients), and Baerveldt (1 patient) aqueous shunts was uneventful in all cases. Early onset of the leak, between postoperative months 1 and 2, was typical. The use of aqueous suppressants, bandage contact lens, conjunctival photocoagulation, sutures, tissue adhesives, conjunctival autografts, and scleral patch grafts were unsuccessful in the described cases. Resolution of the leak occurred after removal of the aqueous shunt and elimination of the causative subconjunctival fistula. Histologic support for fistulization was obtained in 3 cases. Severe complications including endophthalmitis (1 patient), hypotony (4 patients), suprachoroidal hemorrhage (2 patients), and corneal decompensation (3 patients) occurred because of the persistent leaks.

Conclusions

Persistent leak is a rare but important complication after glaucoma aqueous shunt implantation. Early consideration for the presence of a subconjunctival fistula, especially in patients with iridocorneal endothelial syndrome or chronic uveitis, can spare many ineffective efforts to repair the leak and prevent severe vision threatening complications.