This study is a randomized, double-masked (study participants and outcome assessors) trial. During the enrollment period, patients from Menelik Hospital who are planning to have trabeculectomy surgery and who meet the study enrollment criteria will be randomized to receive mitomycin C applied topically or by injection during the surgery.At Menelik Hospital mitomycin-C (MMC) is routinely applied to the eye prior to trabeculectomy by physicians via both sponge and injection routes. The primary outcome is the patient's response to the trabeculectomy procedure, as measured by cumulative complications after a 3-month follow-up period post-operation. Secondary outcome is the change in intraocular pressure after a 3 month follow-up period. The investigators will perform subgroup analyses by stratifying the population according to skin pigmentation to determine whether pigmentation is a predictor of treatment success.