Parameter Fits Using Measured Population AIF vs. Literature AIF in DCE-MRI of Pancreatic Cancer Xenograft Model

Introduction. Dynamic contrast-enhanced MRI (DCE-MRI) has become an important tool in measuring tumour perfusion in animal models of cancer. Standard Kety model analysis of tumour perfusion [1] requires knowledge of the contrast agent concentration in the blood plasma, known as the arterial input function (AIF). Many DCE-MRI studies in mice use an assumed AIF taken from the literature (e.g. Lyng et al. [2], Checkley et al. [3]), even though the mouse strain and cancer model are different. In DCE-MRI of a murine xenograft model of pancreatic cancer, it is possible to extract AIF estimates by measuring concentration time courses in the abdominal aorta. We show here that Kety model parameter fits are improved when a population-averaged AIF is measured from the DCE data in the current study, as opposed to using an assumed AIF from the literature.