title: Cerebral aneurysms associated with segmental dilative arteriopathy of the circle of Willis.
abstract: BACKGROUND
  Dilative arteriopathy is a form of dolichoectasia. It is sometimes observed in the posterior circulation, and it may be associated with various type of stroke. Herein, we report two unusual cases of saccular aneurysms associated with a segmental dilative arteriopathy located in the anterior circulation.
  
  
  METHODS
  The first case is a 39-year-old woman with irregular tortuosity and coiling of the left internal cerebral artery along with saccular aneurysms in this artery. The second case is a 45-year-old woman presenting with a ruptured saccular aneurysm in the coiling of the anterior cerebral artery. In both cases, the aneurysm was clipped successfully, and the patients recovered uneventfully with no neurological deficits.
  
  
  CONCLUSIONS
  Dilative arteriopathy of the circle of Willis is an unusual anomaly and is characterized by tortuous and elongated arteries, which are sometimes observed in patients with a congenital anomaly. This report describes two cases of saccular aneurysm associated with dilative arteriopathy of the circle of Willis with no medical history, which to the best of our knowledge has not previously been described.
authors.affiliation: Department of Neurosurgery, Sapporo Medical University, Sapporo, Japan.
authors.forename: Yoshifumi
authors.initials: Y
authors.lastname: Horita
authors.affiliation: Department of Neurosurgery, Sapporo Medical University, Sapporo, Japan.
authors.forename: Takeshi
authors.initials: T
authors.lastname: Mikami
authors.affiliation: Department of Neurosurgery, Hokkaido University, Graduate School of Medicine, Sapporo, Japan.
authors.forename: Kiyohiro
authors.initials: K
authors.lastname: Houkin
authors.affiliation: Department of Neurosurgery, Sapporo Medical University, Sapporo, Japan.
authors.forename: Nobuhiro
authors.initials: N
authors.lastname: Mikuni
keywords: Anterior cerebral artery; arteriopathy; dolichoectasia; subarachnoid hemorrhage