[Ruptured persistent primitive hypoglossal artery aneurysm: case report].

Persistent primitive hypoglossal artery is less common than persistent primitive trigeminal artery. About one hundred examples of such hypoglossal arteries have been demonstrated by angiography. The origin of persistent primitive hypoglossal artery is the cervical segment of the internal carotid artery, usually at the level of the first to second cervical vertebrae. The artery then enters, with varying degrees of tortuosity, the anterior condyloid (hypoglossal) canal and joints the basilar artery immediately above its lower end. When enlargement of this canal is identified, the presence of a persistent primitive hypoglossal artery should be strongly suspected. The homolateral vertebral artery is frequently hypoplasia. A 66-year-old man was brought to our hospital due to faintness. CT showed thick subarachnoid hemorrhage. Angiography showed that a persistent primitive hypoglossal artery aneurysm was present, but the posterior communicating artery was absent. Right vertebral angiography showed extravasation due to re-rupture of the aneurysm. An operation was performed at day 0 using the left transcondylar approach despite deterioration of SAH grading. Intraoperative re-rupturing occurred and the lower cranial nerves clustered around the aneurysm, so the aneurysm was partially clipped on the dome. The second angiography was carried out at day 10, and there was no vasospasm. Palsy of the lower cranial nerves appeared transiently. A ventricle-peritoneum shunt was required due to normal pressure hydrocephalus, but the patient was discharged with no neurological deficits.