Single stage transcranial exposure of large dural venous sinuses for surgically-assisted direct transvenous embolization of high-grade dural arteriovenous fistulas: technical note

High-grade dural arteriovenous fistulas (DAVFs) with retrograde cortical leptomeningeal drainage are formidable lesions because of their risk for intracranial hemorrhage. Treatment is aimed at occluding venous outflow to achieve obliteration of the fistula. In DAVFs that involve a large dural venous sinus (transverse sigmoid sinus or superior sagittal sinus), occluding venous outflow can be accomplished endovascularly with transvenous embolization. However, in some cases of DAVFs with reflux into cortical leptomeningeal veins, there may be venous restrictive disease downstream, such as occlusive thrombosis, which can prohibit endovascular access via the transfemoral or transjugular routes. In these instances, a transcranial approach can be performed to expose the large dural venous sinus distal to the site of occlusion for direct catheterization of the venous outflow for transvenous embolization. This combined surgical and endovascular strategy provides direct access to the venous outflow and bypasses the site of thrombotic obstruction. In this report, we describe our technique of single stage surgically-assisted transvenous embolization in three patients with high-grade DAVFs involving a large dural sinus. All patients achieved complete obliteration of their DAVFs without any venous related complications. Our technique of surgically-assisted direct transvenous embolization of high-grade DAVFs can be successfully performed as a single stage in the operating room with intraoperative angiography and stereotactic image guidance.