Georgios Krokos1, Neil Thacker1, Ibrahim Djoukhadar1, David Morris1, Alan Jackson1, and Marie-Claude Asselin1
Variability
in the underlying assumptions and mathematical formulations of the commonly
used models for pharmacokinetic analysis of dynamic contrast-enhanced (DCE) MRI
data make model selection not straightforward[1]. The variable noise in DCE-MR images affects
the precision of parameters such that correcting the chi-square for the non-uniform
noise is required for model comparison[2]. After noise correction, the two-compartmental
exchange model fitted the data better, particularly in grade IV glioma,
compared to the extended Tofts and adiabatic approximation to the tissue
homogeneity models. Lengthening the acquisition duration not only provided more
precise parameter estimates but also reduced the mathematical correlations
between parameters.