Analysis workflow illustrated for DCE-MRI data from a Dunning R3327-AT prostate tumor model. (A)
A representative array of signal versus time curves from a tumor region and
adjacent muscle tissue, depicted by the green box on a representative T1-weighed MR image
on the right, is shown. The color boxes indicate three differential temporal patterns in the tumor
(from left to right): blue—continuous slow uptake; green—faster uptake and some
washout; red—rapid contrast uptake and fast washout. On the basis of their temporal shape
[6], as well as their image location, these curves are most
likely associated with necrotic, hypoxic, and well-perfused tumors, respectively. (B) Left: First
four PCs, together with their fractional contribution to the data variability. Right: Spatial
distribution of the magnitude of the corresponding PC scores in the five image slices. (C) PCA
applied only to the DCE data from pixels within the tumor. Left: First four PCs. Right: Spatial
distribution of the magnitude of the corresponding PCs in a representative central tumor slice (note
that the PCA was carried out on the entire data set). (D) cNMF analysis of the data seeking three
solutions. Left: Basic signal versus time curves,
S(t). Right: Spatial distribution of the corresponding weights,
W, in the five tumor slices.