Saturation Coil for Localized Signal Suppression in MPI

The magnetic nanoparticles (MNPs) used as imaging tracers in magnetic particle imaging (MPI) accumulate in off-target organs such as liver or spleen. The signal from the high-concentration MNPs in these off-target organs may overpower the signals from the nearby low-concentration regions targeted during imaging. In this work, we propose using a saturation coil to suppress the localized high intensity MPI signal from the off-target accumulation organs. The results of the proof-of-concept imaging experiments show that, when the saturation coil is placed over the high-concentration region, it can selectively and completely suppress the signal from that region.