Surgical treatment of Type I spinal dural arteriovenous fistulas

Abstract

Object: Type I spinal dural arteriovenous fistulas (SDAVFs) are low-flow vascular shunts fed by radicular arteries in patients who most often present with myelopathy. Although some fistulas are amenable to endovascular embolization, nearly all can be treated with direct microsurgical obliteration.

Methods: The authors reviewed their experience in treating 214 craniospinal arteriovenous malformations and/or fistulas over the last 8 years. Of these, 19 were spinal (9%), of which 15 (79%) were Type I SDAVFs. The authors reviewed the patients' epidemiological characteristics, presenting symptoms, and SDAVF angioarchitecture in all cases. They subsequently analyzed surgical obliteration rates and outcomes of all 11 patients who underwent fistula microsurgical obliteration.

Results: In all patients who underwent microsurgical treatment, complete angiographic obliteration of the fistula was achieved. At follow-up, 10 (91%) of 11 patients exhibited improvement, 1 patient (9%) was the same, and no patients were worse. Specifically, 8 (73%) of 11 patients had improvement in strength and sensation, 5 (71%) of 7 had improvement of bowel/bladder function, and 3 (60%) of 5 had improvement of preoperative paresthesias. There were no wound infections, CSF leaks, or permanent neurological deficits.

Conclusions: Microsurgical treatment of SDAVF provides direct access to the fistula point, allowing for high obliteration rates with excellent long-term improvement of preoperative deficits and limited periprocedural complications.