title: The reliability of high resolution MRI in the measurement of early stage carotid wall thickening.
abstract: OBJECTIVE
  To study the repeatability of common carotid mean wall thickness (MWT) measured with high resolution MRI, in comparison with intima media thickness (IMT) assessed by ultrasound and to investigate the relative capabilities of these two modalities.
  
  
  METHODS
  Ten healthy volunteers and 10 subjects with carotid artery atherosclerosis were imaged with both high resolution MRI and US. Measurement of both MWT and IMT was performed by three blinded observers. Intra- and inter-observer repeatability was calculated and a Bland-Altman plot used to compare IMT and MWT. Circumferential variation in arterial wall thickness was also evaluated.
  
  
  RESULTS
  Intra- and inter-observer repeatability were comparable between IMT and MWT. The Bland-Altman plot showed a difference between IMT and MWT in controls with a trend towards equivalence in atherosclerotic patients. Analysis of circumferential variation in wall thickness by MRI identified greater focal thickening in patients compared with controls (p<0.001), which was not evident with ultrasound (p=0.98).
  
  
  CONCLUSIONS
  MRI and ultrasound have similar repeatability for the assessment of carotid wall thickness. There are differences between MWT and IMT, potentially due to the inclusion of the adventitia by MRI which, in addition to better detection of focal thickening, may provide a more complete estimation of early stage atherosclerosis.
authors: Department of Radiology, University of California, San Francisco, VA Medical Center, San Francisco, California 94121, USA, and Centre de Recherche en Nutrition Humaine Rhône-Alpes, Hôpital Edouard Herriot, Lyon, France. loic.boussel@gmail.com
authors: Loic
authors: L
authors: Boussel
authors: André
authors: A
authors: Serusclat
authors: Michael R
authors: MR
authors: Skilton
authors: Fabrice
authors: F
authors: Vincent
authors: Sophie
authors: S
authors: Bernard
authors: Philippe
authors: P
authors: Moulin
authors: David
authors: D
authors: Saloner
authors: Philippe Charles
authors: PC
authors: Douek
mesh_terms: D000328:Adult; D000368:Aged; D002340:Carotid Artery Diseases / Q000175:diagnosis* / Q000000981:diagnostic imaging / Q000473:pathology; D017536:Carotid Artery, Common / Q000000981:diagnostic imaging / Q000473:pathology; D016022:Case-Control Studies; D003238:Connective Tissue / Q000473:pathology; D018450:Disease Progression; D005260:Female; D006801:Humans; D018810:Magnetic Resonance Angiography; D008297:Male; D008875:Middle Aged; D015588:Observer Variation; D011237:Predictive Value of Tests; D015203:Reproducibility of Results; D017539:Tunica Intima / Q000000981:diagnostic imaging / Q000473:pathology; D017540:Tunica Media / Q000000981:diagnostic imaging / Q000473:pathology; D014463:Ultrasonography