mitomycin-c drops versus subconjunctival 5-fluorouracil for management of early bleb failure

purpose: to compare the efficacy and safety of topical mitomycin-c (mmc) drops versus subconjunctival 5-fluourouracil (5-fu) injections for management of early bleb failure after trabeculectomy or combined phacoemulsification and trabeculectomy with posterior chamber intraocular lens implantation (pt+pciol). methods: in a comparative study, 37 eyes of 37 patients with impending early bleb failure were randomly allocated to mmc 0.02% eye drops (19 eyes) or subconjunctival 5-fu injections (5mg each dose) (18 eyes) for 2 to 4 weeks or. main outcome measures included intraocular pressure (iop), and bleb morphology according to the indiana bleb appearance grading scale. other outcome measures included success rate, number of glaucoma medications, best corrected visual acuity (bcva) and complications. complete success was defined as 5 results: baseline characteristic including age, sex, type of glaucoma, and number of previous surgeries were comparable in the study groups. however, there were more instances of combined pt+pciol in the mmc group as compared to the 5fu group [11 (57.9%) eyes versus 3 (16.7%) eyes, p=0.01]. patients were followed for a mean period of 11.5±8.0 (median= 8.0) versus 10.9±5.4 (median= 11) months in the mmc and 5-fu groups respectively (p=0.58). mean preoperative iop was 20.6±8.8mmhg in the mmc group and 25.8±11.4 mmhg in the 5-fu group (p=0.12), which decreased to 13.2±6.1 and 10.6±4.8mmhg respectively after 12 months (p=0.15). there was no significant difference in bleb extent (p=0.30), height (p=0.157) and vascularity (p=0.26) between the study groups. at the end of the study, complete success was achieved in 13 eyes (68.4%) in the mmc group and 14 eyes (77.8%) in the 5-fu group (p=0.71); qualified success was achieved in 1 eye (5.3%) in the mmc group and no eyes in the 5-fu group. kaplan-meier analysis revealed that survival of success at 8 months (median follow-up) was 89.5% vs 86.5% in the mmc and 5fu groups, respectively. similarly,the number of glaucoma medications (p=0.71) and bcva (p=0.55) were comparable between the study groups. the most common complication related to mmc was punctate epithelial keratopathy observed in 6 eyes (31.5%). the most common complication of 5-fu injections was filamentary keratitis in 7 eyes (38.9%); complication rates were comparable between the study groups (p=0.14). conclusion: for  management of early bleb failure, postoperative application of topical mmc 0.02% drops is comparable to subconjunctival injection of 5fu in terms of efficacy and safety. topical mmc 0.02% drops are more convenient and can be initiated first; 5-fu injections can be reserved for eyes with insufficient response to topical mmc.