title: Carotid artery stenosis: accuracy of contrast-enhanced MR angiography for diagnosis.
abstract: OBJECTIVE
  To assess accuracy of contrast material-enhanced magnetic resonance (MR) angiography as compared with three-dimensional (3D) time-of-flight (TOF) MR angiography and reference digital subtraction angiography (DSA) in diagnosis of carotid artery stenosis.
  
  
  METHODS
  Enhanced and 3D TOF MR angiography and DSA were performed in 51 consecutive patients suspected of having carotid artery stenosis at duplex ultrasonography. Stenoses were measured by two independent observers blinded to clinical information and other test results. Pearson correlation coefficients were used, and kappa for interobserver variabilities was estimated. Sensitivity and specificity of enhanced and 3D TOF MR angiography were calculated and compared with those of DSA.
  
  
  RESULTS
  Pearson correlation coefficients were 0.94 (P <.01) for enhanced angiography versus DSA, 0.92 (P <.01) for 3D TOF angiography versus DSA, and 0.93 (P <.01) for enhanced versus 3D TOF angiography for observer 1 and 0.94 (P <.01), 0.95 (P <.01), and 0.94 (P <.01), respectively, for observer 2. kappa statistics were 0.81 for enhanced angiography, 0.79 for 3D TOF angiography, and 0.78 for DSA. Stenosis measurements of observer 1 at enhanced MR angiography, with inclusion of carotid arteries on the symptomatic side only, compared with those of DSA yielded a sensitivity of 90% (95% CI: 68%, 99%) and a specificity of 77% (95% CI: 55%, 92%). 3D TOF angiography yielded a sensitivity of 86% (95% CI: 67%, 97%) and a specificity of 73% (95% CI: 50%, 89%) compared with those of DSA. For observer 2, sensitivity and specificity for enhanced angiography were 91% (95% CI: 70%, 99%) and 76% (95% CI: 52%, 91%), respectively, and 90% (95% CI: 68%, 99%) and 77% (95% CI: 51%, 92%), respectively, for 3D TOF angiography.
  
  
  CONCLUSIONS
  Accuracy of enhanced MR angiography in diagnosis of severe stenosis is similar to that of 3D TOF MR angiography.
authors.affiliation: Julius Center for Health Sciences and Primary Care, University Medical Center Utrecht, Heidelberglaan 100, Rm E 01.132, 3508 GA Utrecht, The Netherlands.
authors.forename: Paul J
authors.initials: PJ
authors.lastname: Nederkoorn
authors.forename: Otto E H
authors.initials: OE
authors.lastname: Elgersma
authors.forename: Yolanda
authors.initials: Y
authors.lastname: van der Graaf
authors.forename: Bert C
authors.initials: BC
authors.lastname: Eikelboom
authors.forename: L Jaap
authors.initials: LJ
authors.lastname: Kappelle
authors.forename: Willem P T M
authors.initials: WP
authors.lastname: Mali
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D015901:Angiography, Digital Subtraction; D016893:Carotid Stenosis / Q000175:diagnosis*; D005260:Female; D006801:Humans; D018810:Magnetic Resonance Angiography / Q000379:methods*; D008297:Male; D008875:Middle Aged; D015588:Observer Variation; D012680:Sensitivity and Specificity