title: A comparative study of 43 patients with mirror-like intracranial aneurysms: risk factors, treatment, and prognosis.
abstract: OBJECTIVE
  Mirror-like intracranial aneurysms (MirAn) occur symmetrically at the corresponding intracranial arteries and are a subgroup of multiple intracranial aneurysms. The aim of this study was to analyze the risk factors, treatment, and prognosis of MirAn.
  
  
  METHODS
  We retrospectively analyzed 43 cases of MirAn diagnosed between January 2000 and December 2009. The control groups comprised patients with non-mirror-like multiple aneurysms (nMirAn) and single aneurysms (SingAn). Sex, age, localization of MirAn, hypertension, diabetes, smoking, and rupture were identified as potential risk factors for MirAn.
  
  
  RESULTS
  The male to female ratio of the MirAn patients was 1.0:5.1, which was significantly different from that of the nMirAn patients (1.0:1.9, P=0.037) and SingAn patients (1.0:1.3, P<0.001). There was no difference in age (P=0.8741), smoking (P=0.301), diabetes (P=0.267), or hypertension (P=0.874) between the MirAn and nMirAn patients. The aneurysms in 28 MirAn patients (65.1%) involved the internal carotid-posterior communicating arteries; in these patients, the rupture risk was significantly higher for larger aneurysms compared with smaller aneurysms (P<0.05).
  
  
  CONCLUSIONS
  More women suffered from MirAn than nMirAn or SingAn. The most common MirAn sites were the internal carotid-posterior communicating arteries. Our results suggest that MirAn was not associated with age, smoking, hypertension, or diabetes.
authors.affiliation: Neurosurgical Department, Beijing Tiantan Hospital affiliated to Capital Medical University, Beijing, People's Republic of China.
authors.forename: Rong
authors.initials: R
authors.lastname: Wang
authors.affiliation: Neurosurgical Department, Beijing Tiantan Hospital affiliated to Capital Medical University, Beijing, People's Republic of China.
authors.forename: Dong
authors.initials: D
authors.lastname: Zhang
authors.affiliation: Neurosurgical Department, Beijing Tiantan Hospital affiliated to Capital Medical University, Beijing, People's Republic of China.
authors.forename: Jizong
authors.initials: J
authors.lastname: Zhao
authors.affiliation: Neurosurgical Department, Beijing Tiantan Hospital affiliated to Capital Medical University, Beijing, People's Republic of China.
authors.forename: Shuo
authors.initials: S
authors.lastname: Wang
authors.affiliation: Neurosurgical Department, Beijing Tiantan Hospital affiliated to Capital Medical University, Beijing, People's Republic of China.
authors.forename: Yuanli
authors.initials: Y
authors.lastname: Zhao
authors.affiliation: Capital Medical University, Beijing, People's Republic of China.
authors.forename: Hongchuan
authors.initials: H
authors.lastname: Niu
keywords: clinical feature; mirror-like intracranial aneurysm; retrospective analysis; women’s health