The application of gamma knife radiosurgery (GKRS) alone has been expanded for dural arteriovenous fistulas (DAVFs). However, a standardized protocol delineating the appropriate circumstances for GKRS alone in cases of DAVF has yet to be determined.

Among 31 DAVF patients treated according to the Chung-Ang University College of Medicine, Seoul, South Korea, treatment algorithm between February 2009 and November 2014, 20 patients underwent GKRS alone. DAVF patients treated with GKRS alone fell in two main subgroups: DAVF patients without cortical venous reflux (CVR) but with symptoms (n = 8) and DAVF patients with CVR but without a high bleeding risk (defined as CVR with aggressive symptoms including hemorrhage or non-hemorrhagic neurological deficit, n = 11). One DAVF patient with a high bleeding risk had GKRS alone because of difficult endovascular access. Mean radiation volume was 4.8 cc (range, 0.7-14.2 cc), and mean maximal dose was 33.5 Gy (range, 28-38 Gy).

At mean follow-up of 29.1 months (range, 8-69 months), radiological findings demonstrated complete cures in 18 patients (90 %) and subtotal cures in 2 patients (10 %). One patient had a transient complication, but no neurologic sign. All symptomatic patients showed complete resolution.

The treatment algorithm showed GKRS alone may serve as a primary treatment for patients with DAVFs regardless of location and presence of CVR, unless there is a high bleeding risk. However, a multicenter, prospective study is necessary to generalize our treatment algorithm ¹⁾.