Evaluation of spatio-temporal resolution of MPI scanners with a dynamic bolus phantom

Magnetic particle imaging (MPI) is a tomographic imaging method to determine the spatial distribution of magnetic nanoparticles (MNP) within a defined volume. To evaluate the spatio-temporal resolution of existing MPI scanners, we developed dynamic MPI measurement phantoms. These segmented flow phantoms consist of a bolus of ferrofluid tracer material, pumped through a tube system. Using a hydrophobic organic carrier oil, cylindrically shaped bolus of different diameter, length, MNP concentrations, and flow velocity can be emulated. Moving boluses were imaged by MPI and the correlation of spatial resolution und velocity of the bolus was investigated. For all bolus dimension and flow velocity combinations, a decreasing spatial resolution and increasing blurring with increasing bolus velocity and decreasing bolus volume was observed.   Int. J. Mag. Part. Imag. 6(2), Suppl. 1, 2020, Article ID: 2009011, DOI: 10.18416/IJMPI.2020.200901