[A Case of Tentorial Dural Arteriovenous Fistula Treated with Transvenous Embolization Using NBCA]

We report a case of tentorial dural arteriovenous fistula(dAVF)treated with transarterial and transvenous embolization using n-butyl-2-cyanoacrylate(NBCA). A 70-year-old man presented with dysarthria and trunk ataxia. Computed tomography(CT)on admission revealed right cerebellar hemorrhage. Right external carotid angiography demonstrated a tentorial dAVF fed by the marginal tentorial artery, petrosquamous branch of the middle meningeal artery, ascending pharyngeal artery, and artery of foramen rotundum. Right internal carotid angiography demonstrated a shunt fed by the meningohypophyseal trunk. The draining vein was the right basal vein with a varix, which drained into the straight sinus. Thin-slice axial images on magnetic resonance angiography demonstrated a shunt point located on the right tentorial incisura. The lesion was diagnosed as Cognard type IV tentorial dAVF. It was initially treated with transarterial embolization using 25% NBCA, which was injected into the marginal tentorial artery and the petrosquamous branch of the middle meningeal artery. However, owing to partial persistence of the shunt after the procedure, transvenous embolization using NBCA was performed. A microcatheter was navigated through the straight sinus into the basal vein, and a balloon catheter was also navigated to the confluence of the straight sinus and the basal vein to interrupt blood flow and prevent the NBCA from flowing back to the sinus. 80% NBCA was injected into the draining vein near the shunt point. Angiography performed immediately after the procedure revealed complete occlusion of the shunt, and postoperative CT showed no evidence of hemorrhage. Transvenous embolization of tentorial dAVF can be an effective method if a microcatheter can be safely advanced close to the shunt point.