title: Persistent leak after glaucoma aqueous shunt implantation.
abstract: OBJECTIVE
  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.
authors.affiliation: *Department of Ophthalmology, Hôpital Maisonneuve-Rosemont †Department of Ophthalmology, CHU Sainte-Justine, Université de Montréal, Montréal ‡Department of Ophthalmology, CHUS-Hotel-Dieu, Université de Sherbrooke, Sherbrooke, QC, Canada.
authors.forename: Marie-Claude
authors.initials: MC
authors.lastname: Robert
authors.forename: Patrick
authors.initials: P
authors.lastname: Hamel
authors.forename: Pierre
authors.initials: P
authors.lastname: Blondeau
authors.forename: Mark R
authors.initials: MR
authors.lastname: Lesk
mesh_terms: D000328:Adult; D001082:Aqueous Humor / Q000378:metabolism*; D002648:Child; D003229:Conjunctival Diseases / Q000209:etiology* / Q000378:metabolism / Q000601:surgery; D020878:Device Removal; D005260:Female; D005402:Fistula / Q000209:etiology* / Q000378:metabolism / Q000601:surgery; D005901:Glaucoma / Q000601:surgery*; D020327:Glaucoma Drainage Implants; D006801:Humans; D007429:Intraocular Pressure; D008297:Male; D008875:Middle Aged; D011183:Postoperative Complications; D019919:Prosthesis Implantation; D012189:Retrospective Studies; D055815:Young Adult