title: Subarachnoid hemorrhage caused by ruptured posterior inferior cerebellar artery aneurysm arising from the extracranial portion of an anomalous vertebral artery.
abstract: A 42-year-old woman presented with subarachnoid hemorrhage caused by a ruptured posterior inferior cerebellar artery aneurysm arising from the extracranial portion of an anomalous vertebral artery. We speculated that the aneurysm formed by dissection of the media because of its shape and location. Therefore, the aneurysm was isolated by trapping and excised, with occipital artery to posterior inferior cerebellar artery bypass. Histological examination showed a typical true aneurysm without evidence of dissection. This case suggests that an aneurysm of an anomalous artery is caused by hemodynamic stress and is a true aneurysm, not a dissection.
authors: Abashiri Neurosurgical Rehabilitation Hospital, Hokkaido, Japan.
authors: Makoto
authors: M
authors: Katsuno
authors: Rokuya
authors: R
authors: Tanikawa
authors: Nakao
authors: N
authors: Ota
authors: Naoto
authors: N
authors: Izumi
authors: Masaaki
authors: M
authors: Hashimoto
mesh_terms: D000328:Adult; D017542:Aneurysm, Ruptured / Q000000981:diagnostic imaging / Q000473:pathology* / Q000601:surgery; D020785:Central Nervous System Vascular Malformations / Q000000981:diagnostic imaging / Q000473:pathology* / Q000601:surgery; D002548:Cerebral Revascularization / Q000379:methods; D005260:Female; D006801:Humans; D011859:Radiography; D013345:Subarachnoid Hemorrhage / Q000000981:diagnostic imaging / Q000473:pathology* / Q000601:surgery; D014711:Vertebral Artery / Q000002:abnormalities* / Q000000981:diagnostic imaging / Q000601:surgery; D020217:Vertebral Artery Dissection / Q000000981:diagnostic imaging / Q000473:pathology* / Q000601:surgery