title: Wash-in kinetics for gadolinium-enhanced magnetic resonance imaging of carotid atheroma.
abstract: OBJECTIVE
  To determine the wash-in kinetics of intravenous gadolinium into the fibrous cap and lipid core of carotid atheroma, and identify the time following gadolinium administration that maximizes contrast between the cap and core.
  
  
  METHODS
  Seven subjects with carotid artery stenosis were studied. Magnetic resonance (MR) images of the atheroma were acquired using a single-inversion-recovery fast-spin-echo (IR FSE) sequence, which was serially repeated during the first 30 minutes following intravenous gadolinium administration. Postcontrast time was divided into three intervals: <10, 11-20, and >21 minutes. Adjusted signal intensity (SI), signal-to-noise ratio (SNR), and contrast-to-noise ratio (CNR) values for postcontrast images were compared to adjusted precontrast values.
  
  
  RESULTS
  The mean SNRs of the cap and core were significantly elevated in each postcontrast interval compared with mean precontrast values. The CNRs of the cap vs. the core increased by 19.8% (3.03 to 4.14, P = 0.03) in the first 10 minutes following gadolinium administration, and remained elevated over the next two intervals with a slight decrease in the final interval.
  
  
  CONCLUSIONS
  Increased signal and contrast between the cap and core can be achieved by imaging up to 30 minutes following gadolinium administration, with peak enhancement occurring in the first 10 minutes.
authors.affiliation: Russell H. Morgan Department of Radiology and Radiological Sciences, Baltimore, Maryland, USA. bwasser@jhmi.edu
authors.forename: Bruce A
authors.initials: BA
authors.lastname: Wasserman
authors.forename: Suzette G
authors.initials: SG
authors.lastname: Casal
authors.forename: Brad C
authors.initials: BC
authors.lastname: Astor
authors.forename: Anthony H
authors.initials: AH
authors.lastname: Aletras
authors.forename: Andrew E
authors.initials: AE
authors.lastname: Arai
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D001161:Arteriosclerosis / Q000175:diagnosis*; D016893:Carotid Stenosis / Q000175:diagnosis*; D003287:Contrast Media / Q000493:pharmacokinetics*; D005260:Female; D019786:Gadolinium DTPA / Q000493:pharmacokinetics*; D006801:Humans; D007089:Image Enhancement; D007091:Image Processing, Computer-Assisted; D018810:Magnetic Resonance Angiography / Q000379:methods*; D008297:Male; D008875:Middle Aged; D013997:Time Factors
chemical_list: D003287:Contrast Media; D019786:Gadolinium DTPA