title: Five-Year Pooled Data Analysis of the Ahmed Baerveldt Comparison Study and the Ahmed Versus Baerveldt Study.
abstract: OBJECTIVE
  To determine the relative efficacy of the Ahmed-FP7 and Baerveldt BG101-350 implants.
  
  
  METHODS
  Pooled analysis of 2 multicenter, randomized clinical trials.
  
  
  METHODS
  A total of 514 patients aged 18 or older with uncontrolled glaucoma that had failed or were at high risk of failing trabeculectomy were randomized to receive an Ahmed implant (n = 267) or Baerveldt implant (n = 247). Cumulative failure rates (using an intraocular pressure [IOP] target of 6-18 mm Hg inclusive), de novo glaucoma surgery rates, mean IOP, mean glaucoma medication use, and visual acuity were compared.
  
  
  RESULTS
  Baseline characteristics were similar between groups. Mean preoperative IOP of the study population was 31.5 ± 11.3 mm Hg on an average of 3.3 ± 1.1 glaucoma medications. At 5 years, mean IOP was 15.8 ± 5.2 mm Hg in the Ahmed group and 13.2 ± 4.7 mm Hg in the Baerveldt group (P < .001). Mean glaucoma medication use was 1.9 ± 1.5 in the Ahmed group and 1.5 ± 1.4 in the Baerveldt group (P = .007). The cumulative failure rate at 5 years was 49% in the Ahmed group and 37% in the Baerveldt group (P = .007). High IOP was the most common reason for failure in both groups, and de novo glaucoma surgery was required in 16% of the Ahmed group and 8% of the Baerveldt group (P = .006). Failure owing to hypotony occurred in 0.4% of the Ahmed group and 4.5% of the Baerveldt group (P = .002). Visual outcomes were similar between groups (P = .90).
  
  
  CONCLUSIONS
  The Baerveldt group had a lower failure rate, lower rate of de novo glaucoma surgery, and lower mean IOP on fewer medications than the Ahmed group. Baerveldt implantation carried a higher risk of hypotony.
authors.affiliation: Department of Ophthalmology and Vision Sciences, University of Toronto Faculty of Medicine, Toronto, Canada.
authors.forename: Panos G
authors.initials: PG
authors.lastname: Christakis
authors.affiliation: Department of Epidemiology, University of North Carolina at Chapel Hill Gillings School of Global Public Health, Chapel Hill, North Carolina.
authors.forename: Dongyu
authors.initials: D
authors.lastname: Zhang
authors.affiliation: Department of Epidemiology, University of North Carolina at Chapel Hill Gillings School of Global Public Health, Chapel Hill, North Carolina; Department of Ophthalmology, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina. Electronic address: dbudenz@med.unc.edu.
authors.forename: Donald L
authors.initials: DL
authors.lastname: Budenz
authors.affiliation: NIHR Biomedical Research Centre for Ophthalmology, Moorfields Eye Hospital, London, United Kingdom.
authors.forename: Keith
authors.initials: K
authors.lastname: Barton
authors.affiliation: Department of Ophthalmology, Icahn School of Medicine at Mount Sinai, New York Eye and Ear Infirmary of Mount Sinai, New York, New York.
authors.forename: James C
authors.initials: JC
authors.lastname: Tsai
authors.affiliation: Department of Ophthalmology and Vision Sciences, University of Toronto Faculty of Medicine, Toronto, Canada.
authors.forename: Iqbal I K
authors.initials: IIK
authors.lastname: Ahmed
mesh_terms: D000368:Aged; D005260:Female; D005500:Follow-Up Studies; D005901:Glaucoma / Q000503:physiopathology / Q000601:surgery*; D020327:Glaucoma Drainage Implants; D006801:Humans; D007429:Intraocular Pressure / Q000502:physiology*; D008297:Male; D008875:Middle Aged; D011183:Postoperative Complications; D011474:Prosthesis Design; D019919:Prosthesis Implantation / Q000379:methods*; D014065:Tonometry, Ocular; D014130:Trabeculectomy / Q000379:methods*; D016896:Treatment Outcome; D014792:Visual Acuity