Flow Diversion versus Coiling with or without Stenting for Unruptured Wide-Neck Intracranial Aneurysms: A Randomized Comparison

Clinical Snapshot

Key Findings

• P Value: P = 0.60

• Effect Size: FD: 18.6% vs Coiling: 23.3% failure rate

• Primary Outcome: Treatment failure at 12 months

• Nnt Or Sensitivity: No significant difference; NNT not applicable as no benefit demonstrated

• Confidence Interval: RR = 0.80 (95% CI: 0.35-1.83)

Clinical Application

Both treatments available in Australian comprehensive stroke centres with interventional neuroradiology services Results support current practice where coiling remains first-line for most unruptured aneurysms. Flow diverters available through TGA approval but not routinely PBS-funded, making cost-effectiveness considerations important Adults with unruptured wide-neck intracranial aneurysms 7-20mm diameter, particularly ophthalmic aneurysms <10mm

Abstract

BACKGROUND AND PURPOSE: There are few randomized trials comparing coiling (with or without stent placement) and flow diversion (FD) for the treatment of wide-neck unruptured intracranial aneurysms. MATERIALS AND METHODS: EVIDENCE was an investigator-led randomized (1:1) trial conducted in 7 French university hospitals. Patients with 7 to 20-mm intradural unruptured intracranial aneurysms with a 4- to 10-mm neck and a "dome/neck" ratio of ≥1 were randomly allocated to coiling with or without adjunctive stent placement or FD alone. The composite primary efficacy outcome was "treatment failure," defined as initial failure to treat the aneurysm; aneurysm rupture or retreatment during follow-up; death or dependency (mRS> 2); or an angiographic residual aneurysm adjudicated by an independent core laboratory at 12 months. The primary hypothesis (revised for slow accrual) was that FD would decrease treatment failures from 35% to 10%, requiring 90 patients. Primary analyses were intent to treat. RESULTS: Among the 91 enrolled patients, four (two in each group) withdrew consent; 87 patients were included in the analysis: 43 in the FD group and 44 in the control group. Most patients had <10 mm (57/87; 65.5%) asymptomatic ophthalmic aneurysms (75/87, 86.2%). A poor primary outcome, ascertainable in 86 patients, was reached in 8/43 patients with FD (18.6%; 95% CI, 9.7%-32.6%) compared with 10/43 coiling patients (23.3%; 95 CI, 13.1%-37.7%) (RR = 0.80; 95% CI, 0.35-1.83; P = .60). Serious adverse events were similar. CONCLUSIONS: For patients with mostly unruptured, wide-neck ophthalmic aneurysms of <10 mm, FD was not superior to coiling with or without stent placement.

References

1. 1.Boisseau, W., Combaz, X., Levrier, O., Smajda, S., Escalard, S., Piotin, M., Biondi, A., Charbonnier, G., Dargazanli, C., Derelle, A. L., Desal, H., Darsaut, T. E., Raymond, J., Gory, B., & Turjman, F. (2026). Flow diversion versus coiling with or without stenting for unruptured wide-neck intracranial aneurysms: A randomized comparison. AJNR American Journal of Neuroradiology. https://doi.org/10.1016/j.clineuro.2018.06.042