Nonpenetrating glaucoma surgery augmented with MMC shows better tolerability, IOP-lowering than trabeculectomy with MMC

Can J Ophthalmol. 2009;44(1):76-82.

Nonpenetrating glaucoma surgery augmented with mitomycin C was better tolerated, with lower IOP, than trabeculectomy with MMC, but trabeculectomy had better results overall in reaching target IOP, a clinical trial found.

"[Nonpenetrating glaucoma surgery] augmented with MMC was associated with IOP-lowering efficacy comparable to that of [trabeculectomy] plus MMC," the study authors said. "However, significantly fewer patients achieved the target IOP with [nonpenetrating glaucoma surgery] augmented with MMC than with [trabeculectomy] plus MMC. [Nonpenetrating glaucoma surgery] augmented with MMC was better tolerated than [trabeculectomy] plus MMC."

Researchers conducted a systematic review and meta-analysis of eight clinical trials. Of those trials, four were a cohort design and four were randomized, examining 459 open-angle glaucoma eyes. Studies were selected from the Cochrane Library, MEDLINE and EMBASE databases, and meeting abstracts. The meta-analysis' measure of efficacy was weighted mean differences of the percentage of IOP reduction and relative risks.

Clinicians found that reduction in IOP in the nonpenetrating glaucoma surgery group was a nonsignificant percentage, with a weighted mean difference of –1.27% (95% confidence interval [CI] –5.61 to 3.07) at 1 year, –4.55% (–10.35 to 1.24) at 2 years, –0.82% (–8.8 to 7.17) at 3 years and –6.16% (–25.97 to 13.65) at 4 years.

A significantly lower incidence of shallow anterior chamber and cataract was also found in the nonpenetrating glaucoma surgery group.