title: Evaluation of carotid artery stenosis: contrast-enhanced magnetic resonance angiography compared with conventional digital subtraction angiography.
abstract: OBJECTIVE
  To compare retrospectively high-resolution contrast-enhanced magnetic resonance angiography with centric k-space filling and digital subtraction angiography in the assessment of degree of carotid artery stenosis.
  
  
  METHODS
  Two neuroradiologists independently evaluated 14 carotid arteries (in 7 patients), and the degree of carotid stenosis determined was compared to calculate interobserver reliability. Thirty-six carotid arteries (in 18 patients) were then assessed with both contrast-enhanced magnetic resonance angiography and digital subtraction angiography. The degree of stenosis was determined by consensus, and the findings of the 2 modalities were compared.
  
  
  RESULTS
  Close interobserver agreement was found with an intraclass correlation coefficient of 0.98 (95% confidence interval 0.95-0.99). Sensitivity of 86% and specificity of 91% were found for contrast-enhanced magnetic resonance angiography detection of surgically significant carotid stenosis compared with digital subtraction angiography. The Spearman rank correlation test also found a significant correlation (R(s) = 0.90, p < 0.001) in the comparison of the classifications of degree of carotid artery stenosis.
  
  
  CONCLUSIONS
  Contrast-enhanced magnetic resonance angiography shows excellent correlation with digital subtraction angiography for the evaluation of carotid artery disease and has the potential to replace it in the assessment of degree of carotid artery stenosis.
authors.affiliation: Department of Diagnostic Imaging, Ottawa Hospital, Civic Campus, 1053 Carling Ave., Ottawa ON K1Y 5E9. mgoyal@ottawahospital.on.ca
authors.forename: Mayank
authors.initials: M
authors.lastname: Goyal
authors.forename: Julie
authors.initials: J
authors.lastname: Nicol
authors.forename: Dheeraj
authors.initials: D
authors.lastname: Gandhi
mesh_terms: D015901:Angiography, Digital Subtraction; D016893:Carotid Stenosis / Q000145:classification / Q000175:diagnosis* / Q000000981:diagnostic imaging*; D016001:Confidence Intervals; D003287:Contrast Media; D003627:Data Interpretation, Statistical; D006801:Humans; D018810:Magnetic Resonance Angiography / Q000379:methods; D015588:Observer Variation; D012189:Retrospective Studies; D012680:Sensitivity and Specificity
chemical_list: D003287:Contrast Media