Analysis of Multi-delay Arterial Spin Labeling Reveals Inaccuracies in Kidney Blood Flow Using a Single Compartment Perfusion Model

Motivation: single compartment ASL models are less tested in the kidney and are likely distinct from brain kinetic models due to key physiological differences. Goal(s): The goal of this study is to explore the accuracy of a single compartment, general ASL kinetic model in quantifying renal blood flow (RBF). Approach: Seven subjects received brain and kidney ASL scans at four different delay times. Quantitative RBF and cerebral blood flow (CBF) maps were compared using paired t-test. Results: RBF estimates were less stable and more dependent on delay times than CBF estimates. Cortical RBF and corticomedullary RBF ratio was lower at long delay times. Impact: This study highlights the limitations of directly applying brain kinetic models to the kidney and calls for revised models that better accommodate kidney physiology.