title: Otago Glaucoma Surgery Outcome Study: long-term results of 841 trabeculectomies.
abstract: BACKGROUND
  To describe the long-term outcomes of trabeculectomies performed at Dunedin Hospital and followed in the Otago Glaucoma Surgery Outcome Study.
  
  
  METHODS
  Prospective non-comparative case series of 841 eyes of 607 patients who had first trabeculectomies for primary open- or closed-angle glaucoma at Dunedin Hospital between 1976 and 2005 and followed for a mean of 7.5 years (standard deviation 6.0).
  
  
  RESULTS
  The probability of a trabeculectomy controlling the intraocular pressure at 21 mmHg or less at 1, 10 and 20 years was 0.96 (95% confidence interval [CI] 0.95, 0.97), 0.86 (95% CI 0.83, 0.89) and 0.79 (95% CI 0.74, 0.83), respectively. Visual acuity was maintained or improved between preoperative assessment and final follow up in 68% of cases. The probability of not being blind following trabeculectomy at 1, 10 and 20 years was 0.98 (95% CI 0.96, 0.98), 0.83 (95% CI 0.80, 0.87) and 0.70 (95% CI 0.64, 0.76), respectively. The proportion of those with glaucomatous field loss increased during follow up from 16% (44/283) at 0-5 years to 50% (10/20) for those with 21 or more years of follow up. A repeat drainage procedure was required in 65 eyes (8%) (56 Molteno implant insertions and 9 repeat trabeculectomies).
  
  
  CONCLUSIONS
  Intraocular pressure was well controlled by trabeculectomy; however, a steady decline in intraocular pressure control, visual acuity and visual field occurred during follow up.
authors.affiliation: Section of Ophthalmology, Department of Medical and Surgical Sciences, Dunedin, New Zealand. tui.bevin@stonebow.otago.ac.nz
authors.forename: Tui H
authors.initials: TH
authors.lastname: Bevin
authors.forename: Anthony C B
authors.initials: AC
authors.lastname: Molteno
authors.forename: Peter
authors.initials: P
authors.lastname: Herbison
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D002387:Cataract Extraction; D005260:Female; D015812:Glaucoma, Angle-Closure / Q000601:surgery*; D005902:Glaucoma, Open-Angle / Q000601:surgery*; D006801:Humans; D007429:Intraocular Pressure; D008297:Male; D008875:Middle Aged; D015814:Ocular Hypotension; D011183:Postoperative Complications; D013997:Time Factors; D014130:Trabeculectomy; D016896:Treatment Outcome; D014792:Visual Acuity; D014794:Visual Fields