Trabeculectomy with mitomycin C alone or coupled with intracamerular bevacizumab? A 2-year comparative study

Purpose: To compare outcomes of primary trabeculectomy using either mitomycin C (MMC) alone versus MMC augmented with intracamerular bevacizumab in patients with open-angle glaucoma. Methods: Retrospective, cohort, two-centre, comparative study. Patients' data were screened between October 2015 and March 2019, with inclusion requiring a minimum follow-up of 24 months. Primary outcome was intraocular pressure (IOP) lowering at 24 months, with surgical success defined with different maximum IOP targets (≤18, ≤16 and ≤14 mm Hg) and at least 30% reduction and higher than 5 mm Hg. Absolute success was achieved if no IOP-lowering medication was needed and a qualified success if otherwise. Safety outcomes were analysed. Results: A total of 110 eyes underwent trabeculectomy with MMC, 51 of these combined with intracamerular bevacizumab. Both strategies were effective in terms of IOP lowering (baseline vs 2 years postoperatively: 24.4 (8.0) mm Hg vs 12.1 (5.3) mm Hg in the MMC group; 25.1 (8.7) vs 10.8 (3.8) mm Hg in the MMC+bevacizumab group; p<0.001 in both comparisons). The MMC+bevacizumab group had a significant difference towards higher efficacy on absolute success rates at all targets (IOP≤14 or ≤16 or ≤18 mm Hg; p=0.010, p=0.039 and p=0.007, respectively). The large majority (93%) of the MMC+bevacizumab group was drop-free at 24 months, and 41% had IOP below 10 mm Hg. Complication rates were low and similar between groups, with no systemic adverse events. Conclusions: Intracamerular bevacizumab in MMC-augmented primary trabeculectomy increases the chances of obtaining low IOP outcomes. This strategy may be useful when planning for surgeries aiming at target pressures in the low teens. Trial registration number: ISRCTN93098069.