title: Long-term evaluation of the use of Ahmed gonioimplants in dogs with primary glaucoma: nine cases (2000-2008).
abstract: OBJECTIVE
  To evaluate the outcome and describe the complications associated with use of an Ahmed gonioimplant in the treatment of glaucoma in dogs.
  
  
  METHODS
  Retrospective case series.
  
  
  METHODS
  9 client-owned sighted dogs (median age, 9 years) with primary glaucoma. Procedures-Medical records of dogs with primary glaucoma that underwent unilateral gonioimplant placement (in 2000 through 2008), during which a temporalis muscle fascia graft (n = 8) or porcine intestinal submucosa (1) was used to cover the implant tube as it exited the globe, were reviewed. All dogs were treated with mitomycin C in the conjunctival pocket intraoperatively and with tissue plasminogen activator immediately after surgery; 1% prednisolone acetate was applied to the implanted eye daily until failure of the implant. Medical intervention or additional surgery was performed when intraocular pressures (IOPs) were > 20 mm Hg or progressively increasing values were detected.
  
  
  RESULTS
  After gonioimplant placement, IOP was controlled for a variable period in all dogs. Subsequently, IOP exceeded 20 mm Hg in 7 dogs (median postoperative interval, 326 days). Median interval to vision loss despite interventional surgery was 518 days (range, 152 to 1,220 days). Surgical intervention was necessary in 4 dogs to maintain satisfactory IOP. Implant extrusion attributable to conjunctival dehiscence or necrosis occurred in 4 dogs. At 365 days after surgery, 8 dogs retained vision, and 5 dogs retained vision throughout follow-up.
  
  
  CONCLUSIONS
  In dogs with medically refractory primary glaucoma, placement of a gonioimplant appears to be effective in maintaining vision.
authors.affiliation: Department of Small Animal Clinical Sciences, University of Tennessee, Knoxville, TN 37996, USA.
authors.forename: Hans D
authors.initials: HD
authors.lastname: Westermeyer
authors.forename: Diane V H
authors.initials: DV
authors.lastname: Hendrix
authors.forename: Daniel A
authors.initials: DA
authors.lastname: Ward
mesh_terms: D000818:Animals; D004283:Dog Diseases / Q000601:surgery*; D004285:Dogs; D005901:Glaucoma / Q000601:surgery / Q000662:veterinary*; D020327:Glaucoma Drainage Implants / Q000662:veterinary*; D007429:Intraocular Pressure; D012189:Retrospective Studies; D013997:Time Factors