Vol.29 No.2 Original Article PDF

Comparison of outcomes of trabeculectomies using 0.4 mg/ml versus 0.2 mg/ml concentrations of mitomycin-C

Mario V. Aquino, MD, Ma. Margarita L. Lat-Luna, MD, John Vincent Policarpio D. Flores, MD, MSEp

This study compared the outcomes of trabeculectomies using 0.2 mg/ml and 0.4 mg/ml mitomycin-C (MMC) and determined the factors that can predict the postoperative intraocular pressure (IOP).

A prospective, randomized, comparative study was performed involving patients undergoing trabeculectomy who were randomly assigned to either 0.2 mg/ml MMC for 4 minutes or 0.4 mg/ml for 2 minutes. The IOP, bleb characteristics, and occurrence of complications were compared. Age and gender of the patients, preoperative IOP, MMC concentration, bleb characteristics, angle status, and age of the surger y were analyzed to determine if they are predictive factors of the postoperative IOP using univariate and multivariate analyses.

Seventy-four eyes of 68 patients underwent trabeculectomy: 36 eyes were treated with 0.2 mg/ml MMC for 4 minutes and 38 eyes with 0.4 mg/ml MMC for 2 minutes. There was no statistically significant difference in the mean preoperative IOP and postoperative IOP, as well as in the mean percent change in IOP (p = 0.87) between the 2 groups. Univariate and multivariate analyses showed the preoperative IOP (p = 0.02) and the type of filtering bleb (cystic p < 0.001; diffuse p = 0.045) as predictive factors of postoperative IOP. Kaplan-Meier survival curves showed no significant difference between the 2 groups at an average follow-up of 20 weeks.

There is no significant difference in the outcomes of trabeculectomies using 0.2 mg/ml and 0.4 mg/ml MMC. Preoperative IOP and bleb characteristics are factors predictive of successful filtration surgery.

Keywords: Trabeculectomy, Mitomycin-C, Intraocular pressure, Filtering bleb