[Hypoglossal canal dural arteriovenous fistulas treated with transvenous embolization:report of two cases and literature review].

Two cases of hypoglossal canal dural arteriovenous fistulas (HCDAVF) were reported. The clinical manifestation, radiological features, treatment and prognosis were reviewed. Both cases presented chemosis and pulsatile tinnitus. 3D-time-of-flight (TOF) magnetic resonance angiography (MRA) demonstrated abnormal high signal in hypoglossal canal. Cerebral digital subtraction angiography (DSA) showed that these HCDAVFs were supplied by multiple intracranial and extracranial arteries, and fistulas were located in hypoglossal canal. Fistulas were blocked by coils and Onyx-18 through transvenous approach, and the angiography after the embolism showed complete occlusion of fistula. No adverse events after treatment and no recurrence during the follow up were observed.