Paravertebral arteriovenous fistula treated by endovascular coil embolization

A 41-year-old man, without underlying health problems or traumatic episodes, presented with a rare paravertebral arteriovenous fistula (AVF) causing radiculopathy manifesting as gradually progressive right grip weakness, and right thumb, index, and middle finger numbness. Digital subtraction angiography revealed a high flow, single hole paravertebral AVF fed by the right thyrocervical trunk that drained into the epidural venous plexus. The patient underwent endovascular embolization of the AVF via the transarterial approach. The fistula was completely occluded by coil embolization. Postembolization, clinical symptoms improved and 6-month follow-up angiography showed no recurrence of the fistula. Paravertebral AVF is a rare vascular malformation occurring outside the dura mater, fed by dural or epidural branches, and draining primarily into the epidural venous plexus. Paravertebral AVF is usually asymptomatic because of a "reflux-impending mechanism" within the dural sleeves that prevents retrograde drainage into the perimedullary veins. However, in the present case, mechanical compression of the radicular nerve due to a dilated epidural venous plexus resulted in neurological symptoms. We conclude that endovascular surgery is an effective treatment strategy for paravertebral AVF.