Microsurgical Management of a Marginal Sinus Dural Arteriovenous Fistula: 2-Dimensional Operative Video

Dural arteriovenous fistulas (DAVFs) are benign but may present with life-threatening hemorrhage or symptoms of venous hypertension (eg, progressive myelopathy).1-3 DAVFs follow well-described anatomic patterns.4 The marginal sinus is located between the layers of the dura, circumferentially around the foramen magnum. It communicates with the basal venous plexus of the clivus anteriorly and the occipital sinus posteriorly.5,6 Arterial supply to the dura in this region that fistulizes into the sinus arises from meningeal branches from the V3 or V4 segments.  A man in his early 70s presented with chronic neck pain and new onset of left arm and face paresthesias. He had brisk patellar reflexes bilaterally and a marginal sinus DAVF, with numerous dilated veins around the cisterna magna, causing dorsal cervicomedullary compression. Angiography confirmed the diagnosis of DAVF rather than arteriovenous malformation. Endovascular embolization was considered, but surgery was preferable because of poor transarterial access.  The patient underwent left far lateral craniotomy and C1 laminectomy with exposure of the condylar fossa. The dura was carefully elevated laterally, revealing a network of dilated tortuous veins, with multiple points of fistulous connection within the dura emanating in a large venous varix. Indocyanine green videoangiography showed the aberrant flow dynamics. The fistulous point was occluded with aneurysm clips on the venous side, then cauterized and interrupted. The patient was discharged within 3 d of surgery and had full resolution of symptoms at 6 wk. Angiography confirmed complete obliteration of the DAVF. The patient provided written informed consent for treatment. Used with permission from Barrow Neurological Institute, Phoenix, Arizona.