title: Interstudy reproducibility of three-dimensional volume-selective fast spin echo magnetic resonance for quantifying carotid artery wall volume.
abstract: OBJECTIVE
  To assess the interstudy reproducibility of a three-dimensional volume-selective, fast spin echo (FSE) magnetic resonance technique for the assessment of carotid artery wall volume, which is a marker for total carotid plaque volume.
  
  
  METHODS
  Interstudy reproducibility was evaluated in 10 subjects with evidence of carotid artery atherosclerotic disease on carotid Doppler ultrasonography. Subjects were scanned twice with an interscan time of one hour to four days. The carotid artery was imaged in cross-section, and the total carotid arterial wall volume (TWV) was calculated by subtraction of the total carotid lumen volume from the total outer carotid vessel volume.
  
  
  RESULTS
  The mean carotid TWV for the scans was 741 and 734 mm3, respectively, with no significant difference (mean difference 7 mm3; P = 0.5). The time for each study was approximately 20 minutes. The standard deviation of the differences between the measurements was 33 mm3, yielding an interstudy coefficient of variation of 4.4%. Sample size calculations showed that 16 patients would enable this difference in plaque volume over time to be detected with 80% power at a P value of 0.05.
  
  
  CONCLUSIONS
  Volumetric analysis with CMR of carotid artery plaques using a three-dimensional volume-selective FSE is efficient with good interstudy reproducibility, and is well suited for longitudinal studies of progression of carotid atheroma with reasonable sample sizes.
authors.affiliation: Cardiovascular Magnetic Resonance Unit, Royal Brompton Hospital, London, UK. A.Varghese@rbh.nthames.nhs.uk
authors.forename: Anitha
authors.initials: A
authors.lastname: Varghese
authors.forename: Lindsey A
authors.initials: LA
authors.lastname: Crowe
authors.forename: Raad H
authors.initials: RH
authors.lastname: Mohiaddin
authors.forename: Peter D
authors.initials: PD
authors.lastname: Gatehouse
authors.forename: Guang Zhong
authors.initials: GZ
authors.lastname: Yang
authors.forename: David M
authors.initials: DM
authors.lastname: Nott
authors.forename: James M
authors.initials: JM
authors.lastname: McCall
authors.forename: David N
authors.initials: DN
authors.lastname: Firmin
authors.forename: Dudley J
authors.initials: DJ
authors.lastname: Pennell
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D019412:Anatomy, Cross-Sectional; D001161:Arteriosclerosis / Q000175:diagnosis* / Q000000981:diagnostic imaging; D002339:Carotid Arteries / Q000000981:diagnostic imaging / Q000473:pathology*; D016893:Carotid Stenosis / Q000175:diagnosis* / Q000000981:diagnostic imaging; D005260:Female; D006801:Humans; D007089:Image Enhancement / Q000379:methods*; D007091:Image Processing, Computer-Assisted / Q000379:methods; D021621:Imaging, Three-Dimensional / Q000379:methods*; D008279:Magnetic Resonance Imaging / Q000379:methods*; D008297:Male; D015203:Reproducibility of Results; D013382:Subtraction Technique; D013997:Time Factors; D018608:Ultrasonography, Doppler