Transcranial Exposure of Large Dural Venous Sinuses for Direct Transvenous Embolization of High-Grade Dural Arteriovenous Fistulas

Introduction: 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, occluding venous outflow can be accomplished endovascularly with transvenous embolization. In cases of DAVFs with reflux into cortical leptomeningeal veins, there is usually venous restrictive disease downstream that can prohibit endovascular access via the transfemoral or transjugular routes.

Methods: In this study, we describe our technique of surgically assisted transvenous embolization in three patients with high-grade DAVFs involving a large dural sinus with retrograde cortical leptomeningeal drainage.

Results: Surgically assisted transvenous embolization of the DAVF resulted in complete angiographic obliteration in all three patients on postembolization angiography. All had improvement of their preoperative symptoms, and there were no recurrences and no further clinical events after a mean follow-up of 37 months. There were no complications of venous hypertension or venous infarction.

Conclusion: Our technique is unique in that the craniectomy and embolization procedures are performed as a single stage in the operating room with intraoperative angiography and stereotactic image guidance. 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.