title: Risk Factors for the Rupture of Middle Cerebral Artery Bifurcation Aneurysms Using CT Angiography.
abstract: OBJECTIVE
  To investigate the clinical and morphological characteristics associated with risk factors for the rupture of bifurcation-type middle cerebral artery aneurysms (MCAAs).
  
  
  METHODS
  A total of 169 consecutive patients with 177 bifurcation-type MCAAs were reviewed from August 2011 to January 2016. Based on the clinical and morphologic characteristics findings, the risk factors of aneurysm rupture were assessed using statistical methods.
  
  
  RESULTS
  Age, cerebral atherosclerosis, no hypertension, hypertension grade 2 and coronary artery disease (CAD) were negatively correlated with aneurysm rupture. The mean diameter (MD) of the parent and two daughter arteries was negatively correlated with rupture. Aneurysms with irregularity, depth, width, maximum size, aspect ratio, depth-to-width ratio, bottleneck factor, and size ratio were positively correlated with rupture. The multivariate logistic regression model revealed that irregular shape (odds ratio (OR) 2.697) and aspect ratio (OR 3.723) were significantly and positively correlated with rupture, while cerebral atherosclerosis (OR 0.033), CAD (OR 0.080), and MD (OR 0.201) were negatively correlated with rupture. Receiver operating characteristic analysis revealed that the threshold value of the aspect ratio and MD were 0.96 and 2.43 mm, respectively.
  
  
  CONCLUSIONS
  Cerebral atherosclerosis and CAD are protective factors against rupture. Morphological characteristics such as an aneurysm with an irregular shape, a high aspect ratio (>0.96) and a small MD (<2.43 mm) are likely better predictors of rupture.
authors.affiliation: Department of Radiology, Xinqiao Hospital, Third Military Medical University, Chongqing, China.
authors.forename: Guang-Xian
authors.initials: GX
authors.lastname: Wang
authors.affiliation: Department of Radiology, Xinqiao Hospital, Third Military Medical University, Chongqing, China.
authors.forename: Jiao-Yan
authors.initials: JY
authors.lastname: Yu
authors.affiliation: Department of Radiology, Xinqiao Hospital, Third Military Medical University, Chongqing, China.
authors.forename: Li
authors.initials: L
authors.lastname: Wen
authors.affiliation: Department of Radiology, Xinqiao Hospital, Third Military Medical University, Chongqing, China.
authors.forename: Lei
authors.initials: L
authors.lastname: Zhang
authors.affiliation: Department of neurosurgery, Xinqiao Hospital, Third Military Medical University, Chongqing, China.
authors.forename: Ke-Jie
authors.initials: KJ
authors.lastname: Mou
authors.affiliation: Department of Radiology, Xinqiao Hospital, Third Military Medical University, Chongqing, China.
authors.forename: Dong
authors.initials: D
authors.lastname: Zhang
mesh_terms: D000328:Adult; D000367:Age Factors; D000368:Aged; D000369:Aged, 80 and over; D017542:Aneurysm, Ruptured / Q000000981:diagnostic imaging* / Q000209:etiology; D000072226:Computed Tomography Angiography; D005260:Female; D006801:Humans; D006973:Hypertension / Q000150:complications / Q000000981:diagnostic imaging; D002532:Intracranial Aneurysm / Q000000981:diagnostic imaging* / Q000209:etiology; D008297:Male; D008875:Middle Aged; D020768:Middle Cerebral Artery / Q000000981:diagnostic imaging*; D012307:Risk Factors