Comparison of Arterial Input Functions by Magnitude & Phase Signal Measurement in Dynamic Contrast Enhancement MRI Using a Dynamic Flow Phantom

Sangjune Laurence Lee¹, Warren Foltz¹, Brandon Driscoll¹, Ali Fatemi¹, Cynthia Menard¹, Catherine Coolens¹, Caroline Chung¹

Determining the arterial input function (AIF) is critical for the accuracy of kinetic modeling of DCE MRI measures. However, the magnitude signal derived AIF suffers from in-flow, slice profile, and T2* effects. Phase signal has been shown to be an alternative method of acquiring the AIF data. Here, we evaluate the accuracy of AIFs derived from the magnitude and phase signal in a dynamic flow phantom, providing a controlled, gold-standard framework. The phase-derived AIF approached actual peak Gd-DTPA concentrations within all imaging slices and at tested flow rates up to 7.5 mL/s, while the magnitude-derived AIF was grossly attenuated.