A Case of Subarachnoid Hemorrhage Due to Intracranial Anterior Spinal Artery Aneurysm

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.

A Case of Coil Embolization for a Ruptured Anterior Spinal Artery Aneurysm Associated with Bilateral Vertebral Artery Occlusion

“…Aneurysms may occur and rupture because of hemodynamic stress, such as arteriovenous malformation and aortic stenosis, 1,2) following autoimmune diseases, connective tissue diseases, and mycosis, as well as because of fragility of the vessel wall. [3][4][5][6] To our knowledge, five authors reported ruptured ASA aneurysms associated with VA occlusion (Table 1). 1,3,5,7,8) The age range of these cases was 42-83 years; four were bilateral, and two had unilateral VA occlusion.…”

“…There is no consensus about the treatment of ASA aneurysms. 5) Some previous reports showed that craniotomy has good results for ruptured ASA caused by hemodynamic pathology. 5 , 9 , 10) However, Kawamura et al 7) reported a case, where pre-rupture spinal artery aneurysm caused by unilateral VA occlusion was treated conservatively and eventually disappeared.…”

“…To our knowledge, five authors reported ruptured ASA aneurysms associated with VA occlusion ( Table 1 ). 1 , 3 , 5 , 7 , 8) The age range of these cases was 42–83 years; four were bilateral, and two had unilateral VA occlusion. These findings suggest that VA occlusion may be involved in the formation of ASA aneurysms.…”

Subarachnoid Hemorrhage Related to a Ruptured Anterior Spinal Artery Aneurysm Associated with Bilateral Vertebral Artery Occlusion

“…4) In many ASA aneurysms, hemodynamic stress is involved in the pathogenesis in comparison with cerebral aneurysms. 9) ASA aneurysms related to congenital anomalies of the VA are markedly rare. Only one case report on an ASA aneurysm related to vertebral rete mirabile was published by Nagahata et al 5) They reported the hemodynamic development/rupture of aneurysms of the anterior spinal arteries functioning as collateral pathways for bilateral vertebral retes , and emphasized that ASA aneurysms should be suspected when VA abnormalities are observed in the presence of non-typical subarachnoid hemorrhage.…”

Intra-aneurysmal embolization for subarachnoid hemorrhage due to rupture of an aneurysm located at the anterior spinal artery and vertebral artery: illustrative case

“…Several cases of subarachnoid hemorrhage due to rupture of ASA aneurysms have been reported. 2,3,[5][6][7] ASA aneurysms are known to form within the spine and on the feeders of cerebral arteriovenous malformations. Intracranial cases are rare.…”