Two-Step Reconstruction with Spatially Adaptive Regularization for Increasing the Dynamic Range in MPI

Abstract

Magnetic particle imaging is capable of determining very small concentrations of particles if only a single concentration is present in the field-of-view. Meanwhile the determination of particles with widely differing concentrations is still challenging. In a recent work, we introduced a two-step reconstruction method that tackles this problem by isolating the signal of the lower concentrated tracer for a separate reconstruction. In this work, we adapt the two-step reconstruction method in order to apply a joint reconstruction to the entire signal of all particle concentrations. This is achieved by spatially adaptive Tikhonov regularization.