Efficacy and safety of bent ab interno needle goniotomy: a systematic review and meta-analysis

To evaluate the effectiveness and safety of bent ab interno needle goniotomy (BANG) for glaucoma through systematic review and meta-analysis. BANG is a device-free trabecular meshwork-excisional, minimally invasive glaucoma surgery that may offer a lower-cost, more accessible alternative to device-based angle surgery, but its efficacy and safety profile have not been comprehensively consolidated.

MEDLINE, Embase, Cochrane CENTRAL, Scopus, and Web of Science were searched until December 14, 2025. Eligible studies included ≥10 eyes undergoing stand-alone or combined phaco-BANG. Two reviewers independently screened and extracted data; risk of bias was assessed using ROBINS-I v2/RoB-2 and certainty using GRADE. Random-effects inverse-variance meta-analyses pooled intra-ocular pressure (IOP) change at 6 and 12 months and anti-glaucoma medication (AGM) reduction at 6 months; hyphema incidence was pooled using proportional meta-analysis. Leave-one-out and subgroup analyses were performed.

Fourteen studies met inclusion criteria. Across 10 cohorts (248 eyes), IOP decreased by 4.74 mm Hg (95% CI: 2.13-7.35; I² = 96.2%) at 6 months following BANG-containing procedures (predominantly phaco-BANG). Likewise, across 6 cohorts (140 eyes), 12-month IOP reduction was 4.88 mm Hg (0.44-9.31; I² = 98.0%). Across 6 cohorts (161 eyes), AGM burden decreased by 1.30 medications (0.86-1.74; I² = 85.7%). Across 11 cohorts (261 eyes), pooled hyphema incidence was 0.33 (0.14-0.55; I² = 93.3%). Leave-one-out and design-restricted analyses reduced heterogeneity and attenuated effect sizes, suggesting more conservative estimates of efficacy. Certainty of evidence was low.

BANG-containing procedures are associated with modest IOP and medication reductions, with a substantial but typically transient hyphema risk. However, the predominantly phaco-BANG evidence base cannot isolate the independent or clinically meaningful contribution of BANG. Small samples, substantial heterogeneity, limited washout IOP reporting, and low-certainty evidence, support cautious interpretation.