title: Fenestration of the posteroinferior cerebellar artery: case report.
abstract: OBJECTIVE
  Fenestrations of cerebral arteries are rare, but very important to diagnose given their high association with saccular aneurysms. We present the first reported case of a fenestration of the posteroinferior cerebellar artery (PICA).
  
  
  METHODS
  A 62-year-old man who presented with a subarachnoid hemorrhage underwent repeated four-vessel cerebral angiography. An isolated right PICA abnormality consistent with a dissection or fenestration was revealed.
  
  
  METHODS
  The patient underwent surgical exploration of his PICA, which confirmed a PICA fenestration without an associated saccular aneurysm. The fenestration was wrapped with cotton.
  
  
  CONCLUSIONS
  Our case report illustrates the novel anatomic finding of a fenestration of the PICA. Knowledge of this entity would be helpful in the differential diagnosis of a posterior fossa subarachnoid hemorrhage.
authors.affiliation: Department of Neurological Surgery, School of Medicine, University of California San Francisco, USA.
authors.forename: P V
authors.initials: PV
authors.lastname: Theodosopoulos
authors.forename: M T
authors.initials: MT
authors.lastname: Lawton
mesh_terms: D002531:Cerebellum / Q000098:blood supply*; D002533:Cerebral Angiography; D002536:Cerebral Arteries / Q000002:abnormalities / Q000000981:diagnostic imaging / Q000601:surgery; D006801:Humans; D008297:Male; D008875:Middle Aged; D013345:Subarachnoid Hemorrhage / Q000150:complications; D013382:Subtraction Technique; D014057:Tomography, X-Ray Computed