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

Abstract

Purpose: The current study was performed to evaluate the efficacy and safety of late postoperative 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). Methods: 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. Results: 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 postoperative 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 non-randomised 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. Conclusions: 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.