title: Ruptured aneurysm at the choroidal branch of the posterior inferior cerebellar artery: a case report and review of the literature.
abstract: BACKGROUND
  The authors present a rare case of a ruptured aneurysm at the choroidal branch of the posterior inferior cerebellar artery (PICA).
  
  
  METHODS
  A 77-year-old female was admitted to our institute because of sudden onset of severe headache and vomiting. Radiologic examination revealed intraventricular hemorrhage caused by rupture of the aneurysm at the choroidal branch of the PICA. The fusiform aneurysm was resected after ligation via a midline suboccipital approach.
  
  
  CONCLUSIONS
  The conclusions drawn from this experience and a review of the literature include the following: (1) the aneurysm at the branch of the PICA is frequently associated with anomalies of the vascular structure, particularly in hypoplasty of the contralateral PICA; (2) hemodynamic stress is speculated to be a causative factor of these lesions; (3) cases with hypoplasty of the contralateral PICA have the possibility of developing nonmycotic peripheral aneurysms at the branch of the PICA; (4) these aneurysms should be managed immediately because of the high risk of rebleeding.
authors.affiliation: Department of Neurosurgery, Nagasaki University School of Medicine, Nagasaki, Japan.
authors.forename: Nobutaka
authors.initials: N
authors.lastname: Horie
authors.forename: Nobuaki
authors.initials: N
authors.lastname: Takahashi
authors.forename: Shoji
authors.initials: S
authors.lastname: Furuichi
authors.forename: Katsuharu
authors.initials: K
authors.lastname: Mori
authors.forename: Masanari
authors.initials: M
authors.lastname: Onizuka
authors.forename: Keisuke
authors.initials: K
authors.lastname: Tsutsumi
authors.forename: Shobu
authors.initials: S
authors.lastname: Shibata
mesh_terms: D000368:Aged; D017542:Aneurysm, Ruptured / Q000175:diagnosis* / Q000601:surgery*; D002531:Cerebellum / Q000098:blood supply* / Q000000981:diagnostic imaging / Q000473:pathology; D002831:Choroid Plexus / Q000098:blood supply* / Q000000981:diagnostic imaging / Q000473:pathology; D005260:Female; D006801:Humans; D002532:Intracranial Aneurysm / Q000175:diagnosis* / Q000601:surgery*; D011859:Radiography