Comparison of results of initial trabeculectomy with mitomycin C after prior clear-corneal phacoemulsification to outcomes in phakic eyes

Abstract

Purpose: To compare intraocular pressure (IOP) reduction after trabeculectomy with mitomycin C (MMC) in eyes that had prior clear-corneal phacoemulsification to those in a control group of phakic eyes.

Methods: Thirty-nine pseudophakic eyes (38 patients) that underwent initial trabeculectomy with MMC after clear-corneal phacoemulsification between 1997 and 2009 at an academic center were matched on surgeon, age, race, and time of surgery to 39 phakic eyes (39 patients) that underwent the same intervention. Surgical success was defined as: (A) IOP ≤18 mm Hg and ≥20% reduction of IOP, (B) IOP ≤15 mm Hg and ≥25% reduction of IOP, and (C) IOP ≤12 mm Hg and ≥30% reduction of IOP, with or without glaucoma medication. The main outcome measures were success rates, IOP, and number of medications at 1 and 2 years.

Results: The median (range) follow-up time was 36 months (1 to 109 mo) and 38 months (1 to 99 mo) in the pseudophakic and phakic groups, respectively. Success rates were not different between the 2 groups (P=0.17, 0.14, and 0.09 for criteria A, B, and C, respectively). The mean (±SD) preoperative IOP was 21.4±5.9 and 18.6±5.5 mm Hg in the pseudophakic and phakic groups, respectively (P=0.034). IOP decreased by 9.3±5.6 mm Hg versus 5.7±6.9 mm Hg at first year (P=0.057) and by 11.0±7.4 mm Hg versus 5.5±5.5 mm Hg 2 years after surgery (P=0.008). The number of medications was similar at both follow-up intervals in the 2 groups (P=0.980 and 0.679).

Conclusions: Results of initial trabeculectomy with MMC in eyes with prior clear-corneal phacoemulsification are comparable with those in phakic eyes. Clear-corneal phacoemulsification does not seem to affect the success rate of subsequent trabeculectomy with MMC.