title: Distal basilar perforator artery aneurysm: case report.
abstract: OBJECTIVE
  Distal basilar artery aneurysms represent 5 to 8% of intracranial aneurysms. It is crucial to preserve all of the basilar apex perforating vessels when dissecting in this region. This report is the first to describe a rostral basilar perforating artery that was the anatomic origin of a cerebral aneurysm.
  
  
  METHODS
  A 56-year-old woman presenting with subarachnoid hemorrhage underwent initial four-vessel cerebral angiography that did not demonstrate the source of her hemorrhage. A follow-up cerebral angio-gram 9 days later suggested a small aneurysm in the region of the left superior cerebellar artery.
  
  
  METHODS
  A left pterional craniotomy was performed. An aneurysm arising from the origin of a distal basilar perforating artery was identified and obliterated with a small vascular clip. Flow was preserved in the perforating vessel, and the patient had an excellent outcome.
  
  
  CONCLUSIONS
  The findings in the report illustrate the novel anatomic principle that a distal basilar perforating vessel can serve as the anatomic origin of a cerebral aneurysm. Knowledge of this entity would be helpful in avoiding complications at surgery, including perforator injury or aneurysmal rupture in such cases.
authors.affiliation: Department of Cerebrovascular Surgery, Massachusetts General Hospital, Harvard Medical School, Boston, USA.
authors.forename: Z
authors.initials: Z
authors.lastname: Ghogawala
authors.forename: J M
authors.initials: JM
authors.lastname: Shumacher
authors.forename: C S
authors.initials: CS
authors.lastname: Ogilvy
mesh_terms: D017542:Aneurysm, Ruptured / Q000000981:diagnostic imaging / Q000601:surgery*; D001488:Basilar Artery / Q000000981:diagnostic imaging / Q000601:surgery*; D002533:Cerebral Angiography; D003399:Craniotomy; D003937:Diagnosis, Differential; D005260:Female; D006801:Humans; D007091:Image Processing, Computer-Assisted; D002532:Intracranial Aneurysm / Q000000981:diagnostic imaging / Q000601:surgery*; D008875:Middle Aged; D013345:Subarachnoid Hemorrhage / Q000000981:diagnostic imaging / Q000601:surgery*; D014057:Tomography, X-Ray Computed