Endovascular treatment of vertebral arteriovenous fistulas in twenty-two patients.

Twenty-two cases of vertebral arteriovenous fistulas treated by embolization are reported. Although such fistulas are usually asymptomatic they may be occasionally responsible for tinnitus. Neurologic complications are exceptional. Spontaneous fistulas have been found predominantly in the C1-C2 region (9 of 13 cases), while post-traumatic fistulas were located in the C5-C6 region and were often iatrogenic in origin (7 of 9 cases). In 17 cases embolization caused definitive closure of the fistula, while the vertebral artery remained patent. In three patients it was also necessary to close the vertebral artery in order to occlude the fistula. In two instances, endovascular management failed to obliterate the fistula. At present, endovascular treatment is the simplest and one of the least aggressive therapeutic approaches to vertebral arteriovenous fistulas.