Torcular dural AVF: Transvenous onyx embolisation with sinus reconstruction

Transvenous onyx (Microtherapeutics, Irvine, CA, USA) embolization with sinus reconstruction using a venous balloon is a novel technique to embolise dural arterial venous fistula while preserving the sinus. We elucidate the technical tips and tricks that were employed to treat this torcular dural AVF in an elderly male with visual disturbances secondary to papilledema. Right external carotid artery injection revealed a type 2c fistula along the torcula with feeders from the right parietal & petrosal branches of the middle meningeal artery and dural branches of the posterior auricular and the occipital artery. The right distal transverse and the sigmoid were occluded with retrograde flow into the superior sagittal sinus and the cortical veins. XPER CTA analysis revealed the fistula point to be along the wall of the torcula. Through right femoral artery access, a neuron max (Penumbra inc.USA) was placed in the right common carotid artery. An eclipse (Balt Extrusion, France) 6 × 12 mm single lumen balloon was placed in the proximal ECA to achieve flow reduction. Thereafter, through bilateral femoral venous approach, two neuron max 8 F (Penumbra inc.USA) were placed into the left jugular vein. A Copernic RC balloon 10×80 mm (Balt Extrusion, France) was placed from the left to the right transverse sinus. Further, two microcatheters, 1.5 F Marathon (Medtronic, Minneapolis, MI, USA) were navigated into the feeding arteries from the venous end. Microcatheter injections were taken with inflation of the venous balloon to determine the point at which sinus and cortical vein reflux is absent. Following that onyx 18 was injected under biplane fluoroscopy with an adequately inflated arterial and venous balloon. We could achieve retrograde permeation of the onyx into the fistula and the arterial feeders resulting in complete occlusion while preserving the sinus. Careful analysis of the angioarchitecture of the fistula and evaluating for delayed cerebral venous drainage is the key to determining the right strategy to achieve complete occlusion of the fistula.