Postoperative application of mitomycin c improves the complete success rate of primary trabeculectomy: a prospective, randomized trial

Abstract

Background: The intraoperative application of mitomycin c for primary trabeculectomy is associated with potentially sight-threatening side-effects. This study was performed to evaluate the pressure-lowering effect of postoperative application of mitomycin c for primary trabeculectomy and to evaluate the complications of this new technique.

Materials and methods: A randomized, prospective clinical trial with 52 consecutive patients scheduled for glaucoma surgery in one large surgical center was performed. Patients underwent routine trabeculectomy. In group 1, mitomycin c (0.05 mg/ml) was applied topically to the filtering bleb for 5 min on the 3 days after surgery (postoperative application). In group 2, no mitomycin c was applied (controls). The IOP values, visual acuity, number of antiglaucomatous medications and complications were evaluated.

Results: Follow-up was evaluated up to 24 months for all patients. The mean intraocular pressure decreased from 31.1 to 15.4 mmHg in group 1 and from 24.8 to 15.6 mmHg in group 2 (P=0.79; t-test). The average number of medications decreased from 2.5 and 2.4 to 0.4 and 0.6 (P=0.53; t-test) in groups 1 and 2, respectively. No cases of hypotony maculopathy occurred. An individual decrease of more than 25% of the IOP was present in 84.6% in group 1 and in 53.8% in group 2 (P<0.017). Survival analysis for eyes with a complete surgical success revealed a better outcome of eyes in group 1 as compared to the eyes in group 2 (P<0.013; log-rank test).

Conclusions: To our knowledge, this is the first prospective, randomized clinical trial to evaluate the efficacy of postoperative mitomycin c application in primary trabeculectomy. The application of mitomycin significantly reduced the IOP while not increasing the rate of complications.