title: Reproducibility of coronary artery calcified plaque with cardiac 64-MDCT: the Multi-Ethnic Study of Atherosclerosis.
abstract: OBJECTIVE
  The Multi-Ethnic Study of Atherosclerosis is a longitudinal study evaluating determinants of future cardiac events and progression of atherosclerosis. Emerging data are showing that coronary artery calcification (CAC) is a robust independent predictor of future cardiac events and that measurement of progression depends on reproducibility of the measure. Reproducibility previously was reported on baseline scans obtained with both electron-beam tomography (EBT) and MDCT. The aim of this study was to compare the interscan variability for both Agatston and volume scores derived with newer (16- and 64-MDCT) scanners with that derived with older scanners in the Multi-Ethnic Study of Atherosclerosis.
  
  
  METHODS
  The participants in this study were 4,054 persons who underwent dual scanning with EBT (n = 1,716), 4-MDCT (n = 370), 16-MDCT (n = 1,245), or 64-MDCT (n = 723). Agreement on the presence or absence of CAC was assessed with logistic regression models adjusted for age, sex, body mass index, and scanner type. Among participants with CAC, the log-transformed interscan difference was regressed on log-transformed amount of CAC, age, sex, and body mass index.
  
  
  RESULTS
  The percentage agreement for the presence or absence of CAC was high and similar across scanner groups (EBT, 16-MDCT, and 64-MDCT). The greatest adjusted average absolute CAC differences between scans were found with the Aquilion 64 (24%; 95% CI, 20.9-27.6) and LightSpeed Pro 16 (19%; 95% CI, 17.4-21.0) scanners, both differences being significantly greater than with the EBT scanner (16%; 95% CI, 15.4-17.5) (p < 0.05). No differences were found between the EBT, Sensation 16, and Sensation 64 scanners. For volume score, the Aquilion 64 was the only scanner with significantly greater average absolute interscan differences than the EBT scanner (p < 0.001). Volume scoring resulted in lower rescan differences for all scanners.
  
  
  CONCLUSIONS
  For CAC scoring, interscan variability with newer-generation MDCT scanners was similar to but not superior to that with the EBT scanner.
authors.affiliation: Division of Cardiology, Los Angeles Biomedical Research Institute at Harbor-UCLA Medical Center, 1124 W Carson St., RB2, Torrance, CA 90502, USA. mbudoff@labiomed.org
authors.forename: Matthew Jay
authors.initials: MJ
authors.lastname: Budoff
authors.forename: Robyn L
authors.initials: RL
authors.lastname: McClelland
authors.forename: Hyoju
authors.initials: H
authors.lastname: Chung
authors.forename: Nathan D
authors.initials: ND
authors.lastname: Wong
authors.forename: J Jeffrey
authors.initials: JJ
authors.lastname: Carr
authors.forename: Michael
authors.initials: M
authors.lastname: McNitt-Gray
authors.forename: Roger S
authors.initials: RS
authors.lastname: Blumenthal
authors.forename: Robert C
authors.initials: RC
authors.lastname: Detrano
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D015992:Body Mass Index; D003324:Coronary Artery Disease / Q000000981:diagnostic imaging* / Q000453:epidemiology / Q000208:ethnology; D018450:Disease Progression; D005260:Female; D006801:Humans; D016015:Logistic Models; D008297:Male; D008875:Middle Aged; D011379:Prognosis; D011446:Prospective Studies; D011829:Radiation Dosage; D011857:Radiographic Image Interpretation, Computer-Assisted; D015203:Reproducibility of Results; D014057:Tomography, X-Ray Computed / Q000379:methods*; D014481:United States / Q000453:epidemiology