Delayed post-operative use of 5-fluorouracil as an adjunct in medically uncontrolled open angle glaucoma

The current study was performed to evaluate the efficacy and safety of late post-operative use of subconjunctival 5-fluorouracil (5-FU) with ocular massage (OM) after trabeculectomy with or without intraoperative mitomycin C (MMC) in patients with medically uncontrolled primary open angle glaucoma (POAG).

Initial trabeculectomy was performed in 60 eyes of 60 consecutive patients with medically uncontrolled POAG. Thirty eyes (group 1) were randomly assigned to intraoperative MMC (0.2 mg/ml for 3 min) and 30 (group 2) were randomised to standard trabeculectomy. During the first 3 months post-operatively OM and subconjunctival injections of 5-FU (5 mg in 0.5 ml of balanced salt solution) were performed in both groups every time the clinical evaluation suggested imminent bleb failure. Suture lysis was not performed in any patient.

Follow-up ranged from 14 to 53 months (mean 30.17, SD 9.23) in trabeculectomy + MMC treated eyes and from 6 to 54 months (mean 27.37, SD 10.83) in trabeculectomy treated eyes. During the first 3 months of follow-up OM and subconjunctival injections of 5-FU were performed in 14 cases in group 1 and in 18 cases in group 2 (p = NS). A positive response to OM was obtained in 14 of 14 eyes and in 14 of 18 eyes in group 1 and in group 2, respectively (p = 0.042). The difference in post-operative mean IOP between the two groups was statistically significant at each time interval studied (p < 0.001). Success (complete or qualified) was achieved in 50 of 60 eyes (83.33%): 28 (93.3%) in the trabeculectomy + MMC treated group and 22 (73.3%) in the trabeculectomy treated group (p = 0.039). Among the complications seen, the incidence of bleb fibrosis was higher in group 2 (p = 0.0026). By means of post-operative treatment four nonrandomised subgroups were identified: intraoperative MMC + post-operative 5-FU, intraoperative MMC + no post-operative 5-FU, no intraoperative MMC + post-operative 5-FU, no intraoperative MMC + no post-operative 5-FU. The eyes treated with intraoperative MMC and post-operative 5-FU had a better long-term (48 months) cumulative probability of success (100%); treatment with intraoperative MMC or post-operative 5-FU alone was followed by a success rate of 87.1% and 72.2%, respectively. The cumulative probability of success after only trabeculectomy was 56% (p < 0.05). One case of hypotony maculopathy was found in the subgroup treated only with intraoperative MMC.

This study confirms the effectiveness and relative safety of delayed post-operative 5-FU treatment in patients with clinical evidence of bleb failure. Only when OM had caused a lowering of IOP were late subconjunctival injections of 5-FU followed by good control of IOP. The use of intraoperative MMC may ensure a greater IOP decrease after OM.