title: Morphological and clinical risk factors for posterior communicating artery aneurysm rupture.
abstract: OBJECTIVE
  Recent studies have shown that posterior circulation aneurysms, specifically posterior communicating artery (PCoA) aneurysms, are more likely to rupture than other aneurysms. To date, few studies have investigated the factors contributing to PCoA aneurysm rupture. The authors aimed to identify morphological and clinical characteristics predisposing to PCoA aneurysm rupture.
  
  
  METHODS
  The authors retrospectively reviewed 134 consecutive patients with PCoA aneurysms managed at their facility between July 2003 and December 2012. The authors divided patients into groups of those with aneurysmal rupture (n = 39) and without aneurysmal rupture (n = 95) and compared morphological and clinical characteristics. Morphological characteristics were mainly evaluated by 3D CT angiography and included diameter of arteries (anterior cerebral artery, middle cerebral artery, and internal carotid artery), size of the aneurysm, dome-to-neck ratio, neck direction of the aneurysmal dome around the PCoA (medial, lateral, superior, inferior, and posterior), aneurysm bleb formation, whether the PCoA was fetal type, and the existence of other intracranial unruptured aneurysm(s).
  
  
  RESULTS
  Patients with ruptured PCoA aneurysms were significantly younger (a higher proportion were < 60 years of age) and a significantly higher proportion of patients with ruptured PCoA aneurysms showed a lateral direction of the aneurysmal dome around the PCoA, had bleb formation, and the aneurysm was > 7 mm in diameter and/or the dome-to-neck ratio was > 2.0. Multivariate logistic regression analysis showed age < 60 years (OR 4.3, p = 0.011), history of hypertension (OR 5.1, p = 0.008), lateral direction of the aneurysmal dome around the PCoA (OR 6.7, p = 0.0001), and bleb formation (OR 11, p < 0.0001) to be significantly associated with PCoA aneurysm rupture.
  
  
  CONCLUSIONS
  The present results demonstrated that lateral projection of a PCoA aneurysm may be related to rupture.
authors.affiliation: Departments of Neurosurgery.
authors.forename: Hidetoshi
authors.initials: H
authors.lastname: Matsukawa
authors.forename: Motoharu
authors.initials: M
authors.lastname: Fujii
authors.forename: Gensuke
authors.initials: G
authors.lastname: Akaike
authors.forename: Akihiro
authors.initials: A
authors.lastname: Uemura
authors.forename: Osamu
authors.initials: O
authors.lastname: Takahashi
authors.forename: Yasunari
authors.initials: Y
authors.lastname: Niimi
authors.forename: Masaki
authors.initials: M
authors.lastname: Shinoda
mesh_terms: D000368:Aged; D017542:Aneurysm, Ruptured / Q000000981:diagnostic imaging / Q000209:etiology*; D002533:Cerebral Angiography; D002941:Circle of Willis / Q000000981:diagnostic imaging*; D005260:Female; D006801:Humans; D002532:Intracranial Aneurysm / Q000000981:diagnostic imaging / Q000209:etiology*; D008297:Male; D008875:Middle Aged; D012189:Retrospective Studies; D012307:Risk Factors