Device selection and clinical outcomes of adjunctive techniques for ruptured intracranial aneurysms: Insights from...

Adjunctive techniques are frequently required in endovascular treatment (EVT) for ruptured intracranial aneurysms (RIAs) with complex morphology. However, comprehensive nationwide data on technique selection and its relationship with outcomes remain limited. We aimed to clarify anatomical and clinical factors associated with technique selection and to evaluate short-term outcomes using a large nationwide registry.

The Japanese Registry of Neuroendovascular Therapy (JR-NET) 4 included over 4,000 RIAs treated between 2015 and 2019. After exclusions, 3,600 patients treated with balloon-assisted coil embolization (BAC), double-microcatheter coil embolization (DMC), or stent-assisted coil embolization (SAC) were analyzed. Multinomial logistic regression identified factors associated with treatment selection, and multivariable logistic regression evaluated predictors of favorable outcome (modified Rankin Scale; mRS 0-2) and mortality at 30 days.

Wide-neck and large RIAs were associated with DMC and SAC, while bifurcation RIAs were more often treated with DMC. BAC remained the most frequently used technique. Thirty-day outcomes were primarily determined by World Federation of Neurosurgical Societies (WFNS) grade and aneurysm morphology, rather than treatment type. WFNS grade IV-V was linked to a markedly lower chance of favorable outcome (OR 0.10, 95% CI 0.07-0.14), whereas neither DMC nor SAC showed an independent effect compared with BAC.

In this nationwide registry, technique selection was chiefly determined by aneurysm morphology and location, while outcomes were influenced by patient severity and aneurysm complexity. These findings, from the largest nationwide registry of EVT for RIAs, provide real-world evidence to guide treatment planning.