title: Posterior auricular artery as an alternative donor vessel for extracranial-intracranial bypass surgery.
abstract: BACKGROUND
  Sometimes the superficial temporal artery (STA) is not available for an extracranial-intracranial (EC-IC) bypass procedure. An alternative vessel for an EC-IC bypass is the posterior auricular artery (PAA) if it extends to the temporoparietal area with a diameter large enough. We assessed the prevalence of an appropriate PAA as an alternative donor vessel and report three illustrative cases in which the PAA was used for EC-IC bypass surgery.
  
  
  METHODS
  A literature search was performed on the use of the PAA as a donor vessel for bypass surgery. Secondly, a prospective database of bypass surgeries was reviewed to calculate the prevalence of a PAA with a diameter of at least 1 mm in the parietotemporal area. Finally, three illustrative cases are reported that describe various indications for the revascularisation procedures with their clinical, surgical and imaging features.
  
  
  RESULTS
  Two articles have previously described the use of the PAA for bypass surgery and their results are summarised. The prevalence of a PAA that would be appropriate for an EC-IC bypass in patients with intracranial vascular pathology is 5.7%. The presented cases demonstrate that the PAA can be successfully used for EC-IC bypass surgery with good flow velocities and patency.
  
  
  CONCLUSIONS
  The PAA is a rarely described as an appropriate donor vessel for an EC-IC bypass. Its prevalence is 5.7% and it can successfully be used as an alternative donor vessel. The awareness among cerebrovascular surgeons about the presence of a PAA and knowledge about its anatomy may be valuable.
authors.affiliation: Department of Neurosurgery, University Hospital Zürich, Frauenklinikstrasse 10, 8091, Zürich, Switzerland, mrgermans@hotmail.com.
authors.forename: Menno R
authors.initials: MR
authors.lastname: Germans
authors.forename: Luca
authors.initials: L
authors.lastname: Regli
mesh_terms: D000328:Adult; D002342:Carotid Artery, External / Q000601:surgery*; D002343:Carotid Artery, Internal / Q000601:surgery*; D002548:Cerebral Revascularization / Q000379:methods*; D016208:Databases, Factual; D054644:Ear Auricle / Q000098:blood supply*; D005260:Female; D006801:Humans; D020244:Infarction, Middle Cerebral Artery / Q000601:surgery*; D008297:Male; D009072:Moyamoya Disease / Q000601:surgery*; D019635:Neurosurgical Procedures / Q000379:methods; D011446:Prospective Studies; D016896:Treatment Outcome