[Vertebral arteriovenous fistula presenting with subarachnoid hemorrhage: a case report].

We report a rare case of a vertebral arteriovenous fistula presenting with subarachnoid hemorrhage (SAH). A 60-year-old man was admitted to our hospital with a sudden onset of headache and neck pain. A neurological examination showed no abnormalities. Computed tomography scans revealed SAH in the pontine cistern and cistern magna. Although the first cerebral angiogram failed to depict the cause of bleeding, the second angiogram on day 15 demonstrated an arteriovenous fistula in the left vertebral artery at C4-5, which was draining into the internal vertebral venous plexus and forming a venous pouch. The fistula was successfully obliterated by transarterial embolization using detachable platinum coils. In patients with SAH with predominance in the posterior fossa, attention should also be paid to spinal vascular lesions. Three-dimensional digital angiography and digital subtraction angiography allow a reliable visualization of such lesions.