Jack T. Skinner1,2, Mary E. Loveless1,2, Todd E. Peterson2,3, Thomas E. Yankeelov2,3, Mark D. Does1,2
1Biomedical Engineering, Vanderbilt University, Nashville, TN, United States; 2Institute of Imaging Science, Vanderbilt University, Nashville, TN, United States; 3Radiology & Radiological Sciences, Vanderbilt University, Nashville, TN, United States
DCE-MRI characterizes tissue in terms of physical properties, such as the extracellular/extravascular volume fraction (ve), by indirectly measuring the kinetics of a contrast agent into and out of the interstitial space. The fitted model parameters, including ve, are potentially biased by confounding water dynamics, which are not accounted for in the model. In contrast to MRI, radiotracer imaging with SPECT is insensitive to water dynamics. Estimates of ve were obtained using DCE-MRI and dual-isotope SPECT imaging in a rat glioma model and the results showed a large and consistent overestimation by DCE-MRI.