title: Ruptured aneurysm of a posterior inferior cerebellar artery communicating artery. Case report and histological findings.
abstract: A hypertensive 60-year-old man presented with a rare aneurysm arising from the posterior inferior cerebellar artery (PICA) communicating artery, manifesting as subarachnoid hemorrhage with intraventricular hemorrhage. Angiography showed a small aneurysm arising from a fine and tortuous artery interconnecting the bilateral vermian branches of distal PICAs. The right PICA was absent and its vermian territory was supplied by the left PICA through this communicating artery. The right anterior inferior cerebellar artery was also connected to the vermian branch of the right PICA. At surgery, a reddish and apparent fusiform aneurysm was noted at the top of the arterial loop under the cerebellar vermis. Microsurgical trapping and removal of the aneurysm was performed without complication. Histological examination demonstrated typical findings of a true aneurysm. Only four previous cases of aneurysm of the communicating artery between the bilateral distal PICAs have been reported. In all five reported cases including ours, the PICA communicating artery contributed to the collateral blood supply of the contralateral vermian territory based on vascular anomalies. Hemodynamic stress and congenital vulnerability may have caused this aneurysm. Trapping is suitable to treat this precarious aneurysm if other collateral vessels supply the contralateral vermian territory.
authors.affiliation: Department of Neurosurgery, Kohnan Hospital, Sendai, Miyagi, Japan.
authors.forename: Shin-ichiro
authors.initials: S
authors.lastname: Sugiyama
authors.forename: Miki
authors.initials: M
authors.lastname: Fujimura
authors.forename: Takashi
authors.initials: T
authors.lastname: Inoue
authors.forename: Hiroaki
authors.initials: H
authors.lastname: Shimizu
authors.forename: Mika
authors.initials: M
authors.lastname: Watanabe
authors.forename: Teiji
authors.initials: T
authors.lastname: Tominaga
mesh_terms: D017542:Aneurysm, Ruptured / Q000000981:diagnostic imaging / Q000473:pathology* / Q000601:surgery; D001488:Basilar Artery / Q000002:abnormalities* / Q000000981:diagnostic imaging / Q000473:pathology*; D020785:Central Nervous System Vascular Malformations / Q000000981:diagnostic imaging / Q000473:pathology* / Q000601:surgery; D002531:Cerebellum / Q000098:blood supply*; D006801:Humans; D002532:Intracranial Aneurysm / Q000000981:diagnostic imaging / Q000473:pathology* / Q000601:surgery; D008297:Male; D008875:Middle Aged; D011859:Radiography; D013345:Subarachnoid Hemorrhage / Q000000981:diagnostic imaging / Q000473:pathology* / Q000601:surgery; D016896:Treatment Outcome; D014656:Vascular Surgical Procedures / Q000379:methods