Results of the surgical treatment of perimedullary arteriovenous fistulas with special reference to embolization

Abstract

This retrospective study was performed to evaluate the results of surgical treatment and the use of preoperative embolization in managing perimedullary arteriovenous fistulas (AVFs). The authors studied 20 consecutive patients with perimedullary AVFs who underwent surgical treatment. Arteriovenous shunts were at the level of the cervical spine in five patients, the thoracic spine in 12, and the conus medullaris in three patients. Of the 20 AVFs, three were fed by the anterior spinal artery only, three by the posterior spinal artery, and 14 by both the anterior and posterior spinal arteries. Nine patients had varices that compressed the spinal cord. Eleven patients underwent surgery alone, and 9 patients underwent surgery combined with adjuvant preoperative embolization. Preoperative embolization remarkably reduced the blood flow through AVFs and facilitated subsequent surgical procedures. Postoperative angiography revealed complete disappearance of the AVF in 16 patients. However, small fistulas persisted in the other four patients whose large lesions were fed by the anterior spinal artery. Neurological status was improved in 11 patients, unchanged in eight, and worse in one patient postsurgery. Effective interruption of a spinal AV shunt was obtained by surgery in all cases, even when the anterior spinal artery was involved. For large and high-flow AVFs, embolization proved to be a useful adjunct to surgery.