Abstract
We report a very rare case of a ruptured intracranial anterior spinal artery (ASA) aneurysm. A 66-year-old man presented with gradually deteriorating occipitalgia and mild conscious disturbance. He had a history of hypercholesteremia and diabetes mellitus. There was no evidence of collagen disease or inflammation reaction in his physical examination and laboratory data. The first computed tomography (CT) scan revealed thick subarachnoid hemorrhage (SAH) in front of the brain stem with a little intraventricular clot. However, the cerebral angiography (CAG) showed no apparent aneurysm other than right vertebral artery (VA) occlusion with collateral circulation. Repeat cerebral angiography gradually disclosed the presence of an ASA aneurysm. Therefore, the ASA aneurysm was clipped through the right lateral suboccipital approach under trans-cranial motor evoked potential (MEP) monitoring on Day 61. The amplitude of MEP did not decrease during the operation. The patient did not neurologically deteriorate after surgery. It is previously reported that spinal artery aneurysm should be treated by direct or endovascular surgery because of the risk of rupture. However, recent reports showed that spinal artery aneurysm sometimes regressed spontaneously if it is not flow related. In this case, because of the right vertebral artery occlusion, the fenestrated ASA received hemodynamic stress by collateral circulation.
Ruptured aneurysm of the spinal artery requires precise diagnosis and meticulous handling depending on the individual pathogenesis.