Onyx Embolization as a First Line Treatment for Intracranial Dural Arteriovenous Fistulas with Cortical Venous Reflux

Abstract

Our purpose was to present our experience regarding embolization of intracranial dural arteriovenous fistulas (DAVFs) with cortical venous reflux using Onyx, a non-adhesive liquid embolic agent. From January 2006 to December 2007, 16 patients (12 men and 4 women) with a mean age of 61 years (range 42 - 78) with an intracranial DAVF with cortical venous reflux underwent at least one transarterial embolization using Onyx. According to the Cognard classification, 2 lesions were grade V, 5 were grade IV, 6 were grade III, 2 were grade IIa+b, and 1 was grade IIb. The clinical presentation included 5 hemorrhagic deficits, 10 non-hemorrhagic manifestations, and 1 patient was asymptomatic. Twenty-four embolization sessions were performed in 16 patients with an average of 3 arterial feeders (range 1 - 9) embolized per DAVF. Immediately after embolization, complete occlusion was achieved in 9/16 (56%) patients after the first session. Further postembolization surgical treatment was performed in 3 patients. Partial reperfusion occurred in 1 patient at the time of mean follow-up of 3.7 months (range 0 - 12). Treatment has been completed for 11/16 patients with angiographic cure in 10/11 (91%). An infratentorial bleeding complication related to embolization occurred in one patient with temporary worsening of the patient's gait disturbance. At the time of mean clinical follow-up of 4.5 months (range 0 - 12), no procedure-related permanent morbidity was added to our cohort. According to our experience, embolization of intracranial DAVFs with cortical venous drainage using Onyx is feasible with promising results, indicating stability at the time of mid-term follow-up. In very complex DAVFs additional embolization material might be necessary, and in some cases surgery is warranted.