Torcular Dural Arteriovenous Fistula: A Retrospective Observational Study of Patient, Angiographic, and Treatment...

Torcular dural arteriovenous fistulas (dAVFs) are rare, often have an aggressive natural history, and present unique challenges because of complex vascular supply and involvement of bilateral venous sinuses. The study audits the authors' institutional experience treating patients with torcular dAVFs.

All patients with torcular dAVFs from January 2013 to July 2024 were included. Baseline patient and angioarchitecture characteristics were recorded, alongside treatment strategy. Functional outcome at last clinical follow-up was measured using modified Rankin Scale (mRS) score. Univariate and multivariable logistic regressions assessed association between patient characteristics and dichotomized mRS.

Seventeen patients (mean age 65 ± 17 years) were included; 53% were female. Most patients (88%) were symptomatic: 18% presented with hemorrhage, 47% with nonhemorrhagic global neurological deficit, and 24% with focal nonhemorrhagic neurological deficit. Most (14/17, 82%) had high-grade dAVFs (Borden II/III and Cognard IIb-IV). Endovascular embolization was used in 71%, whereas surgery was used in 12%. Angiographic cure was achieved in 63% of patients. Overall, 76% of patients had good functional outcomes (mRS 0-2). On univariate and multivariate analysis, both focal nonhemorrhagic neurological deficit ( P = .015) and baseline mRS ( P = .044) were associated with improved functional outcome.

Borden II/Cognard 2A/B lesions are best treated by transarterial or combined transarterial/transvenous embolization, whereas Borden III/Cognard III/IV lesions are best treated by transarterial embolization or surgical disconnection. Transvenous approaches are reserved for lesions where the fistulous point is accessible. Patients with good functional status at presentation or focal neurological deficits improved after treatment.