Dural Arteriovenous Fistula Involving an Isolated Sinus Treated Using Transarterial Onyx Embolization

and microvascular decompression (MVD) of the facial nerve for a hemifacial spasm.A computed tomography scan obtained at the time of her initial presentation showed curvilinear subcortical calcification and sulcus effacement, predominantly in the right temporal lobe (Fig. 1A).Susceptibility-weighted magnetic resonance imaging (SWI) then demonstrated multiple curvilinear flow voids along the cerebral surface, thus suggesting the presence of a vascular anomaly.Magnetic resonance angiography (MRA) performed to evaluate the possibility of a vascular lesion, revealed a DAVF of the isolated right transverse sinus as well as cortical venous reflux (Fig. 1B).Digital subtraction angiography (DSA) demonstrated a DAVF with an isolated right transverse sinus, supplied by the transosseous branches of the bilateral occipital artery, and the petrosquamous branch of the right middle meningeal artery as well as dural branches from the right vertebral artery.There was retrograde cortical venous reflux (CVR) via leptomeningeal veins from the temporal lobe (Fig. 2A, B).Due to our fear of the risk of hemorrhage or venous infarction associated with CVR, we decided to perform endovascular treatment of the DAVF.Intervention was performed with the patient under general anesthesia.An intravenous bolus of 4000 IU of heparin was administered following placement of a 6-French guiding sheath in the right femoral artery.