Can the Two-Compartment Model for DCE-MRI Fit Contrast Concentration Curves Accurately Over a Heterogeneous Region of Interest?

Xiaobing Fan¹, Aytekin Oto¹, Gregory S. Karczmar¹

The nonlinearity of two-compartment model (TCM) of dynamic contrast-enhanced MRI (DCE-MRI) was studied using computer simulations and an example of clinical prostate DCE-MRI. Even when each individual contrast media concentration v.s. time curve (C(t)) within a region of interest (ROI) satisfies the TCM, the averaged C(t) over the ROI may not satisfy the TCM. Our computer simulation results showed that the Ktrans derived from fitting the averaged C(t) was 20% to 30% smaller than average of all of the Ktrans values for each pixel in the ROI. This is substantial error, and the error for many individual patients will be even higher, leading to errors in diagnosis.