title: Inter-study reproducibility of 3D volume selective fast spin echo sequence for quantifying carotid artery wall volume in asymptomatic subjects.
abstract: OBJECTIVE
  To determine, in asymptomatic subjects, the inter-study reproducibility of a three-dimensional (3D) volume selective fast spin echo (FSE) cardiovascular magnetic resonance sequence for the assessment of carotid artery wall volume as a measure of atheroma burden.
  
  
  METHODS
  Inter-study reproducibility was evaluated in 16 asymptomatic volunteers (10 male, 6 female). Both carotid arteries were scanned twice with a median inter-scan time of 5 days. The images were acquired 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 T1-weighted TWV for the first and second scans was 828 and 821 mm(3), respectively (mean difference 7 mm(3), p=0.45). The standard deviation (S.D.) of the differences between the measurements was 38 mm(3) yielding an inter-study coefficient of variation of 4.6%. The time for each study was approximately 30 min. For the longitudinal evaluation of carotid atheroma burden with pharmacological intervention versus placebo, 32 subjects would enable a difference of 38 mm(3) to be detected with a significance level of 5% with 80% power.
  
  
  CONCLUSIONS
  Volumetric analysis with carotid CMR in asymptomatic subjects using a 3D volume-selective FSE is time-efficient with good inter-study reproducibility, and is well suited for longitudinal studies of carotid atheroma with reasonable sample sizes.
authors.affiliation: Cardiovascular Magnetic Resonance Unit, Royal Brompton Hospital, Sydney Street, London SW3 6NP, UK.
authors.forename: A
authors.initials: A
authors.lastname: Varghese
authors.forename: L A
authors.initials: LA
authors.lastname: Crowe
authors.forename: R H
authors.initials: RH
authors.lastname: Mohiaddin
authors.forename: P D
authors.initials: PD
authors.lastname: Gatehouse
authors.forename: G Z
authors.initials: GZ
authors.lastname: Yang
authors.forename: D N
authors.initials: DN
authors.lastname: Firmin
authors.forename: D J
authors.initials: DJ
authors.lastname: Pennell
mesh_terms: D000328:Adult; D000368:Aged; D050197:Atherosclerosis / Q000175:diagnosis; D002340:Carotid Artery Diseases / Q000175:diagnosis; D017536:Carotid Artery, Common / Q000033:anatomy & histology*; D002343:Carotid Artery, Internal / Q000033:anatomy & histology*; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008279:Magnetic Resonance Imaging / Q000379:methods*; D008297:Male; D008875:Middle Aged; D012016:Reference Values; D015203:Reproducibility of Results; D012189:Retrospective Studies; D012307:Risk Factors