Trabeculectomy with mitomycin C in pseudophakic patients with open-angle glaucoma: Outcomes and risk factors for failure

PURPOSE: To evaluate tonometric outcomes of trabeculectomy with mitomycin C in pseudophakic patients with open,angle glaucoma and associated risk factors for failure. DESIGN: Retrospective cohort study. METHODS: Seventy-three pseudophakic patients (89 eyes) with primary open-angle, normal-tension, exfoliative, or pigmentary glaucoma were recruited. Success rates were defined according to three criteria: (A) intraocular pressure (IOP) <= 18 mm Hg and IOP reduction >= 20%; (B) IOP <= 15 mm Hg and IOP reduction >= 25%; and (C) IOP <= 12 mm, Hg and IOP reduction >= 30%. IOP, visual acuity, complications, and additional interventions were documented after surgery. Cox's proportional hazard regression analysis was used to identify risk factors for failure. RESULTS: Mean IOP (+/-SD) decreased from a preoperative value of 18.8 +/- 6.6 mm Hg to 10.2 +/- 5.1 mm Hg at one year and to 10.0 +/- 4.2 at two years (P < .001 for both). Average number of preoperative medications decreased from 3.0 +/- 1.1 to 0.5 +/- 1.0 at one year and to 0.5 +/- 0.9 at two years (P < .001 for both). For criteria A, B, and C, success rates (+/-SE) were 87% +/- 4%, 83% +/- 5%, and 76% +/- 5% at 1 year and 67% +/- 4%, 58% +/- 8%, and 50% +/- 7 at two years. Laser suture lysis was performed in 30 eyes, and 11% of those required a second glaucoma procedure. CONCLUSION: Increasing age, use of a limbus-based conjunctival flap, and performance of laser suture lysis were factors that were associated with a smaller risk of failure. Present findings indicate that trabeculectomy with mitomycin C provides acceptable long,term success rates in pseudophakic patients, with a low incidence of complications.