Intracranial Dural Arteriovenous Fistula Can Mimic Sigmoid Sinus Wall Anomalies Induced Pulsatile Tinnitus: Caution Before Considering It's Venous.

Abstract

Objective: To highlight that dural arteriovenous fistula (DAVF) can exist in subjects with unilateral vascular pulsatile tinnitus (PT), positive internal jugular vein (IJV) compression tests, and radiologic evidence of sigmoid sinus wall anomalies (SSWA).

Methods: A retrospective analysis was conducted on 80 subjects with PT as the primary symptom and intracranial DAVF detected based on magnetic resonance angiography results. Among them, IJV and retroauricular compression tests and temporal bone computed tomography (CT) were performed. The moth-eaten sigmoid plate sign and DAVF-induced SSWA were defined, and their correlation with PT duration was studied.

Results: Significant differences were observed between ipsilateral IJV and retroauricular compression outcomes in DAVFs located at the transverse-sigmoid sinus (P < .001) and hypoglossal canal (P = .026). Among 71 subjects with CT data, the moth-eaten sign was found in 29 of 37 subjects (sensitivity 78.4%, 95% CI 0.63-0.89) with DAVFs at the transverse-sigmoid sinus. SSWA and jugular bulb (JB) anomalies were observed in 40.8% of subjects. PT duration significantly differed between subjects with SSWA and those without SSWA (P < .0026).

Conclusion: The presence of SSWA on CT and a positive IJV compression test should not be considered conclusive for diagnosing venous PT. The "moth-eaten sigmoid plate" sign on non-contrast CT and positive retroauricular compression are strong indicators of DAVF as the primary cause of PT.