title: Carotid artery: elliptic centric contrast-enhanced MR angiography compared with conventional angiography.
abstract: OBJECTIVE
  To determine the accuracy of elliptic centric contrast material-enhanced magnetic resonance (MR) angiography by using conventional angiography as the reference standard.
  
  
  METHODS
  Fifty patients were examined prospectively with contrast-enhanced MR angiography and conventional angiography. The two examinations were performed within 1 week of each other. Two patients underwent conventional angiography of only one carotid artery, which yielded 98 arteries for comparison.
  
  
  RESULTS
  With conventional angiography as the reference standard and by using a 70% threshold for internal carotid arterial diameter stenosis, maximum intensity projection (MIP) images had a sensitivity of 93.3%, specificity of 85.1%, and accuracy of 87.6%, whereas reformatted transverse source images had a sensitivity of 83.3%, specificity of 97.0%, and accuracy of 92.8%. Interobserver variability for conventional angiograms was 0.97, for MIP images was 0.91, and for source images was 0.90. The contrast-enhanced MR angiographic technique had a sensitivity of 88.9% and specificity of 58.1% for the presence of irregularity and/or ulceration. All 50 examinations were triggered appropriately so that minimal or no venous signal intensity was depicted.
  
  
  CONCLUSIONS
  Contrast-enhanced elliptic centric three-dimensional MR angiography offers high-spatial-resolution, venous-suppressed images of the carotid arteries that appear to be adequate to replace conventional angiography in most patients examined prior to carotid endarterectomy.
authors.affiliation: Department of Diagnostic Radiology, Mayo Clinic and Foundation, 200 1st St SW, Rochester, MN 55905, USA. jhuston@mayo.edu
authors.forename: J
authors.initials: J
authors.lastname: Huston
authors.forename: S B
authors.initials: SB
authors.lastname: Fain
authors.forename: J T
authors.initials: JT
authors.lastname: Wald
authors.forename: P H
authors.initials: PH
authors.lastname: Luetmer
authors.forename: C H
authors.initials: CH
authors.lastname: Rydberg
authors.forename: D J
authors.initials: DJ
authors.lastname: Covarrubias
authors.forename: S J
authors.initials: SJ
authors.lastname: Riederer
authors.forename: M A
authors.initials: MA
authors.lastname: Bernstein
authors.forename: R D
authors.initials: RD
authors.lastname: Brown
authors.forename: F B
authors.initials: FB
authors.lastname: Meyer
authors.forename: T C
authors.initials: TC
authors.lastname: Bower
authors.forename: C D
authors.initials: CD
authors.lastname: Schleck
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D000792:Angiography; D016893:Carotid Stenosis / Q000000981:diagnostic imaging*; D003287:Contrast Media; D005260:Female; D006801:Humans; D018810:Magnetic Resonance Angiography / Q000379:methods*; D008297:Male; D008875:Middle Aged; D011237:Predictive Value of Tests; D011446:Prospective Studies; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity
chemical_list: D003287:Contrast Media