title: Nonbifurcating cervical carotid artery diagnosed by MR angiography.
abstract: OBJECTIVE
  A nonbifurcating cervical carotid artery is a branching anomaly in which the ECA has no proximal main trunk. We report its incidence and characteristic features on MRA.
  
  
  METHODS
  We retrospectively reviewed MRAs of 2866 patients obtained by using a standard noncontrast MRA protocol and two 1.5T MR imaging units and reviewed the English language literature to assess the occurrence and features of this nonbifurcating artery.
  
  
  RESULTS
  We diagnosed 6 cases, indicating an incidence of 0.21%, and found 11 cases reported in the literature. Analysis of all 17 cases demonstrated no laterality or sex predominance. The most prevalent pattern of branching order from proximal to distal was the F-L trunk, the distal trunk of the ECA, and the OA.
  
  
  CONCLUSIONS
  A nonbifurcating cervical carotid artery is rare but not as extremely rare as previously considered, and its correct diagnosis is necessary to avoid complications during interventional radiologic procedures or head and neck surgeries.
authors.affiliation: Department of Diagnostic Radiology, Saitama Medical University International Medical Center, Japan. auchino@saitama-med.ac.jp
authors.forename: A
authors.initials: A
authors.lastname: Uchino
authors.forename: N
authors.initials: N
authors.lastname: Saito
authors.forename: T
authors.initials: T
authors.lastname: Watadani
authors.forename: W
authors.initials: W
authors.lastname: Mizukoshi
authors.forename: R
authors.initials: R
authors.lastname: Nakajima
mesh_terms: D000368:Aged; D002339:Carotid Arteries / Q000002:abnormalities* / Q000473:pathology*; D005260:Female; D006801:Humans; D015994:Incidence; D007564:Japan / Q000453:epidemiology; D018810:Magnetic Resonance Angiography / Q000706:statistics & numerical data*; D008297:Male; D008875:Middle Aged; D015203:Reproducibility of Results; D018570:Risk Assessment; D012680:Sensitivity and Specificity