Dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) and computed tomography (DCE-CT) provide independent measures of biomarkers related to @entity5 perfusion. We compared the reproducibilities and absolute values of DCE-MRI and DCE-CT biomarkers in the same @entity5 in an animal model, to investigate the physiologic validity of both approaches. DCE-MRI and DCE-CT were each performed sequentially on three consecutive days in each of twelve @entity35 bearing C6 @entity11 xenografts. DCE-MRI yielded endothelial transfer constant (K(trans)), extracellular, extravascular space volume fraction (v(e)), and contrast agent reflux rate constant (k(ep)); and DCE-CT, blood flow (BF), blood volume (BV), mean transit time ( @entity98 ), and permeability-surface area product (PS) using Tofts and deconvolution physiological models, with 6.6 and 0.4 seconds temporal resolutions, respectively. Variability in DCE-CT and DCE-MRI were evaluated by variance components analysis. Intra- @entity35 coefficients of variation for DCE-CT parameters BF, BV, @entity98 and PS were 25%, 22%, 18% and 23%; and for DCE-MRI parameters K(trans), k(ep) and v(e) were 23%, 16% and 20%, respectively. Mean (  SD) BF, BV, @entity98 and PS were: 44.6 (  13.7) ml min(-1) 100 g(-1), 5.7 (  1.5) ml 100 g(-1), 10.8 (  2.3) seconds, and 14.6 (  4.7) ml min(-1) 100 g(-1), respectively. Mean (  SD) K(trans), k(ep) and v(e) were: 0.21 (  0.05) min(-1), 0.68 (  0.14) min(-1), and 0.29 (  0.06), respectively. Permeability estimates from DCE-MRI (K(trans)) were 44% higher than from DCE-CT (PS), despite application of appropriate corrections. DCE-MRI and DCE-CT biomarkers of @entity5 perfusion have similar reproducibilities suggesting that they may have comparable utility, but their derived parameter values are not equivalent.

Reproducibility and comparison of DCE-MRI and DCE-CT perfusion parameters in a XXXX @entity5 model.

@entity5 :: ('MESH:D009369', 'Disease') :: ['tumor', 'tumors'] @entity11 :: ('MESH:D005910', 'Disease') :: ['glioma'] @entity98 :: ('CHEBI:53233', 'Chemical') :: ['MTT'] @entity35 :: ('10116', 'Species') :: ['rat', 'rats']
@entity35 :: (10116,Species) :: ['rat']
