Cervical spinal arteriovenous fistulae: A case series and simplified classification

Introduction: Spinal arteriovenous fistulae at the cervical region rarely develop with specific findings on angioarchitecture and symptomatology that differ from that of the thoracic and lumbar spinal shunt. In this case series, angioarchitecture, treatment outcome, and management of lesions were presented by a simplified classification. Materials and methods: Seven patients (mean age, 69.0 years; 5 women and 2 men) who presented to our hospital and related facilities from November 2007 to July 2020 were included in this study. The onset was subarachnoid hemorrhage in 6 and progressive myelopathy in 1 patient. If the shunt remained due to embolization, direct surgery was performed. In analyzing the shunt angioarchitecture, superselective angiography was performed, including microballoon occlusion of the distal artery. Results: Among 6 patients with hemorrhagic onset, the shunt was present in 4 epidural, 2 dural, and 4 perimedullary locations. No radicular type was observed. Concurrent shunts were observed in 2 patients with dural and perimedullary and 2 with epidural and perimedullary lesions. Embolization was performed in 4 patients (2 epidural, 1 dural, and 1 perimedullary types), and shunt disappearance was obtained in 3 patients. Post-embolization infarction occurred in two patients. One patient with a shunt in the dura mater at the C4 level had no shunt in the endovascular therapy alone without any complications; one patient underwent a direct surgery after partial embolization; one patient gave up embolization due to poor access; one patient underwent Cyberknife because the shunt was anterior to the dura mater, and surgery was not indicated; and one patient was under observation due to difficulty of both embolization and direct surgery. Discussion and conclusion: Endovascular procedure for the cervical spinal AVF was considered when a shunt presentation was complicated, and embolization alone could be obtained into no shunt in a specific case. Microsurgery aimed to obliterate the use of shunts in neuroendoscopy with appropriate neurophysiological monitoring, to provide treatment. The choice of treatment reflects the location, lesion pathophysiology, and structurers that should be carefully considered. In this article, the current status of concepts of cervical spinal arteriovenous fistulae was reviewed.