Mitomycin C Trabeculectomy for Refractory Glaucoma: A Comparison between 0.25 and 0.5mg/ml of Mitomycin C

ABSTRACT

To determine the optimum concentration of mitomycin C(MMC) in patients with refractory glaucoma undergoing trabeculectomy, we retrospectively examined 31 eyes of 22 patients with refractory glaucoma who underwent trabeculectomy with 0.25mg/ml MMC for 5 minutes. They were case matched with a group of 36 eyes of 28 patients who had undergone trabeculectomy with 0.5mg/ml MMC for 5 minutes by using age, gender, type of refractory glaucoma, preoperative intraocular pressure(IOP), and preoperative medications as variables. MMC was applied between the sclera and Tenon's capsule during trabeculectomy, and scleral flap was closed with tight releasable sutures. No statistically significant differences were found in mean IOP between the two groups at the one, three, six, and nine months postoperative periods. The mean follow-up was 9.3 months in the 0.25mg group and 9.8 months in the 0.5 mg group(p=0.70). At the last postoperative visit, 81%(25 eyes) in the 0.25mg group and 86%(31 eyes) in the 0.5mg group had an IOP less than 21mmHg with or without glaucoma medication(p=0.79). At the last postoperative visit, there were no statistically significant differences in mean IOP(17.2 +/- 8.6mmHg and 17.2 +/- 7.3mmHg, respectively, p=0.99), mean number of medications(0.6 +/- 0.9 and 0.5 +/- 0.7, respectively, p=0.77), and change in visual acuity(3 eyes and 6 eyes lost more than 2 lines of vision, respectively, p=0.75) between the two groups. The incidence of complications were similar between the two groups. Our data suggests similar efficacy and safety in trabeculectomy with 0.25 and 0.5mg/ml MMC for 5 minutes.