Rescue of failing or failed trabeculectomy blebs with slit-lamp needling and adjunctive mitomycin C in Indian eyes

PURPOSE: The aim of this study is to investigate the efficacy and safety of needling-revision augmented with a high dose of mitomycin C (MMC) in failing or failed blebs after trabeculectomy in Indian eyes. METHODS: Prospective, noncomparative, interventional study. All patients (>18 years) who had raised intraocular pressure (IOP) following trabeculectomy (>6 weeks and <2 years), who had a flat bleb, bleb encapsulation, and/or required antiglaucoma medication (AGM) for IOP control were eligible for inclusion. MMC was injected subconjunctivally at least ½ hour before the needling procedure was carried out at the slit lamp in the outpatient's clinic. RESULTS: Thirty-nine eyes of 38 patients were included. The median follow-up was 20 months and time interval between trabeculectomy and needle revision was 113 days. Initially, in all cases, aqueous flow was re-established with a raised bleb; 7 eyes required repeat needling. IOP decreased from median 24 mmHg (Q1 21, Q3 27, interquartile range [IQR] 6, range 18–35) preneedling to median 14 mmHg (Q1 10, Q3 16, IQR 6, range 6–18) postneedling at last follow-up (P < 0.0001, 95% confidence interval [CI]: 8.2–13.0). The use of AGM reduced from median 1 (Q1 0, Q3 3, IQR 3, range 0–4) preneedling to median 0 postneedling (P < 0.0001, 95% CI: 1–2). Complete success was seen in 28 eyes (71.8%, 95% CI: 71.1%–96.4%); another 5 eyes (12.8%) were controlled with AGM (qualified success) with overall success of 84.6%. Most complications were transient in nature with resolution within 1 week. One patient developed hypotony, and another developed a late bleb leak. CONCLUSION: Needling revision augmented with high-dose MMC, at the slit lamp, effectively rescues failing or failed filtration, and appears to be safe.