Needling after trabeculectomy - does augmentation by anti-metabolites provide better outcomes and is Mitomycin C better than 5-Fluoruracil? A systematic review with network meta-analyses

Purpose Favourable outcome after glaucoma surgery depends on proper control of the inflammatory response. Failing filtration bleb and consequently increased intraocular pressure is an important cause of continuous visual field deterioration after uncomplicated glaucoma surgery. The present systematic review and meta-analysis aimed to compare the effects of employing either Mitomycin C (MMC), 5-Fluoruracil (5-FU) or no anti-metabolite in needling revision of trabeculectomies. Methods We performed a systematic literature search in PubMed, Cochrane and EMBASE to identify randomized and non-randomized trials published between year 2000 and March 2019 comparing the efficacy of needling filtering blebs when using no anti-fibrotic agent, MMC or 5-FU in patients with glaucoma. Efficacy was defined as intraocular pressure at 12 months or latest follow-up, rate of complications, rates of success and the number of re-needling cases. Comparisons were made using network meta-analyses. Results We identified one randomized trial and five retrospective trials. Twelve months after needling revision of trabeculectomy, no significant difference was observed when comparing the effect of the use of MMC with 5-FU or without any use of anti-metabolite on intraocular pressure, complication rates, qualified success, complete success or number of re-needling cases. Conclusion We found no significant difference in the efficacy of using either MMC, 5-FU or no anti-metabolite in needling revision of trabeculectomies. The number of studies meeting our inclusion criteria was limited. Considering the design of studies, only one was randomized leading to an overall low quality of evidence on the subject matter. Further research is warranted.