title: Imaging of distal internal carotid artery by ultrasonography with a 3.5-MHz convex probe.
abstract: OBJECTIVE
  Conventionally, carotid ultrasonography has been performed with a 7.5-MHz linear probe to evaluate the extracranial internal carotid artery (ICA). However, usually only the carotid bulb or proximal portion of the ICA can be evaluated. We attempted to evaluate the distal extracranial ICA with a 3.5-MHz convex probe.
  
  
  METHODS
  The subjects were 17 consecutive patients with ICAs free of occlusive disease and 3 other patients with distal extracranial ICA stenosis. Using a 7.5-MHz linear probe and a 3.5-MHz convex probe, we performed long-axis B-mode imaging of the ICAs to evaluate the distance between the distal limit of visualized ICA and the bifurcation of the common carotid artery.
  
  
  RESULTS
  The distal limit of the ICA, visualized with a 7.5- or a 3.5-MHz probe, was 31+/-11 or 57+/-8 mm distal to the common carotid artery bifurcation, respectively. In the 3 patients with distal extracranial ICA stenosis, the lesion could be successfully diagnosed with only the 3.5-MHz probe.
  
  
  CONCLUSIONS
  This form of carotid imaging is feasible and may be potentially useful in the evaluation of carotid disease.
authors.affiliation: Division of Strokology, Department of Cardiovascular Medicine and Clinical Research, Osaka-Minami National Hospital, Kawachinagano City, Osaka, Japan.
authors.forename: Kenichi
authors.initials: K
authors.lastname: Todo
authors.forename: Manabu
authors.initials: M
authors.lastname: Watanabe
authors.forename: Ryuzo
authors.initials: R
authors.lastname: Fukunaga
authors.forename: Ken
authors.initials: K
authors.lastname: Araki
authors.forename: Shiro
authors.initials: S
authors.lastname: Yamamoto
authors.forename: Makiko
authors.initials: M
authors.lastname: Rai
authors.forename: Taku
authors.initials: T
authors.lastname: Hoshi
authors.forename: Masaru
authors.initials: M
authors.lastname: Nukata
authors.forename: Akihiko
authors.initials: A
authors.lastname: Taguchi
authors.forename: Naokazu
authors.initials: N
authors.lastname: Kinoshita
mesh_terms: D015901:Angiography, Digital Subtraction; D001783:Blood Flow Velocity; D002343:Carotid Artery, Internal / Q000000981:diagnostic imaging*; D016893:Carotid Stenosis / Q000175:diagnosis* / Q000000981:diagnostic imaging; D002533:Cerebral Angiography; D006801:Humans; D011237:Predictive Value of Tests; D012680:Sensitivity and Specificity; D014463:Ultrasonography / Q000295:instrumentation* / Q000379:methods