title: Long-term outcomes of Ahmed glaucoma valve implantation in refractory glaucomas.
abstract: OBJECTIVE
  To evaluate the long-term efficacy of intraocular pressure (IOP) reduction and complications of Ahmed glaucoma valve (AGV) implantation (New World Medical, Inc, Rancho Cucamonga, California, USA) in refractory glaucoma.
  
  
  METHODS
  Retrospective cohort study.
  
  
  METHODS
  Retrospective medical records from 64 patients (78 eyes) with refractory glaucoma who underwent AGV implantation with a minimum of three years of follow-up were reviewed. Data regarding age, gender, race, eye laterality, specific glaucoma diagnosis, best-corrected visual acuity (BCVA), number of medications, IOP, visual fields, surgical complications, and follow-up interval were collected from all visits and were analyzed. The primary outcome measure was cumulative probability of success defined as IOP of less than 21 mm Hg and of 5 mm Hg or more with a minimum of 15% reduction from baseline IOP, without additional glaucoma surgery or loss of light perception. Secondary outcomes included IOP and number of medications at three, six, 12, 24, 36, 48, and 60 months after surgery, surgical complications, and final BCVA.
  
  
  RESULTS
  The cumulative probability of success was 80% and 49% at one and five years, respectively. IOP was reduced from a mean of 30.4 +/- 10.7 mm Hg to 17.0 +/- 5.0 mm Hg at 12 months and 15.9 +/- 3.0 mm Hg at 60 months (P < .001). The number of medications decreased from 3.2 +/- 1.0 medications at baseline to 1.6 +/- 0.4 at 12 months and 2.1 +/- 0.2 at 60 months (P < .001). Prior glaucoma surgery and the silicone type of AGV were statistically significant risk factors for failure (P < .001).
  
  
  CONCLUSIONS
  Approximately 50% of single-plate AGV implantations in refractory glaucoma were considered successful after five years of follow-up. Prior glaucoma surgery was a statistically significant risk factor for failure.
authors.affiliation: Glaucoma Division, Jules Stein Eye Institute, David Geffen School of Medicine, University of California Los Angeles, Los Angeles, CA 90095, USA.
authors.forename: Carlos
authors.initials: C
authors.lastname: Souza
authors.forename: Duc H
authors.initials: DH
authors.lastname: Tran
authors.forename: Jane
authors.initials: J
authors.lastname: Loman
authors.forename: Simon K
authors.initials: SK
authors.lastname: Law
authors.forename: Anne L
authors.initials: AL
authors.lastname: Coleman
authors.forename: Joseph
authors.initials: J
authors.lastname: Caprioli
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000959:Antihypertensive Agents / Q000008:administration & dosage; D002648:Child; D005260:Female; D005500:Follow-Up Studies; D005901:Glaucoma / Q000503:physiopathology / Q000601:surgery*; D020327:Glaucoma Drainage Implants; D006801:Humans; D007429:Intraocular Pressure / Q000502:physiology; D007431:Intraoperative Complications; D008297:Male; D008875:Middle Aged; D011183:Postoperative Complications; D019919:Prosthesis Implantation; D012189:Retrospective Studies; D012307:Risk Factors; D014065:Tonometry, Ocular; D016896:Treatment Outcome; D014792:Visual Acuity; D014794:Visual Fields
chemical_list: D000959:Antihypertensive Agents