title: Comparison of standard trabeculectomy versus microtrabeculectomy as a surgical treatment for glaucoma: a randomized clinical trial.
abstract: BACKGROUND
  To determine the effect of scleral flap size on the medium-term intraocular pressure control and complication rates after augmented trabeculectomy.
  
  
  METHODS
  Prospective randomized clinical trial.
  
  
  METHODS
  Glaucoma patients undergoing primary trabeculectomy. Exclusion criteria included previous ocular surgery apart from cataract surgery, secondary glaucoma and age under 18.
  
  
  METHODS
  Patients were randomized to either standard trabeculectomy (4 × 4 mm scleral flap) or microtrabeculectomy (2 × 2 mm scleral flap), both with adjustable sutures and antimetabolites. Bleb needling was performed as required. Patients were evaluated at day 1, weeks 1, 3, 6 and months 3, 6, 12, 18 and 24 postoperatively.
  
  
  METHODS
  Vision, intraocular pressure, complications and failure (intraocular pressure ≥ 21 mmHg or not reduced by ≥20% from baseline, intraocular pressure ≤ 5 mmHg, repeat glaucoma surgery and no light perception vision).
  
  
  RESULTS
  Forty-one patients were recruited; 20 had standard trabeculectomy, and 21 had microtrabeculectomy. At 2 years, the mean intraocular pressure and cumulative probability of failure was 12.4 ± 4.6 mmHg and 0.28 for standard trabeculectomy, and 11.5 ± 3.6 mmHg and 0.27 for microtrabeculectomy (P = 0.50 and 0.89, respectively). One patient in each group required Baerveldt device implantation. Vision reduced ≥2 Snellen lines in 15% in the standard trabeculectomy group and 25% in the microtrabeculectomy group, mainly from cataract (P = 0.48).
  
  
  CONCLUSIONS
  Both trabeculectomy techniques achieved good intraocular pressure reduction and had similar complication rates. Scleral flap size had no significant effect on medium-term intraocular pressure control and complication profile.
authors.affiliation: Department of Ophthalmology, Wellington Hospital, Wellington, New Zealand.
authors.forename: Ghee Soon
authors.initials: GS
authors.lastname: Ang
authors.forename: Kenneth Cy
authors.initials: KC
authors.lastname: Chan
authors.forename: Ali
authors.initials: A
authors.lastname: Poostchi
authors.forename: Simon
authors.initials: S
authors.lastname: Nicholas
authors.forename: Wayne
authors.initials: W
authors.lastname: Birchall
authors.forename: Laura
authors.initials: L
authors.lastname: Wakely
authors.forename: Anthony P
authors.initials: AP
authors.lastname: Wells
mesh_terms: D000368:Aged; D005260:Female; D005901:Glaucoma / Q000503:physiopathology / Q000601:surgery*; D006801:Humans; D007429:Intraocular Pressure / Q000502:physiology; D008297:Male; D008866:Microsurgery / Q000379:methods*; D011183:Postoperative Complications; D011446:Prospective Studies; D012590:Sclera / Q000601:surgery; D013524:Surgical Flaps; D014130:Trabeculectomy / Q000379:methods*; D016896:Treatment Outcome; D014792:Visual Acuity / Q000502:physiology