Reducing displacement artifacts by warping system matrices in efficient joint multi-patch magnetic particle imaging

The reconstruction of multi-patch magnetic particle imaging data requires a compromise between image quality and calibration time. While optimal image quality is ensured by the joint reconstruction approach, a system matrix needs to be acquired for each patch. One can reuse system matrices by shifting them in space, which decreases the calibration effort but leads to distortions due to field imperfections. In this work, we introduce a method for reducing displacement artifacts in the efficient joint multi-patch reconstruction. Based on the magnetic fields we propose a mapping that warps the central system matrix to capture the spatial displacement of off-center system matrices. In this way, we can maintain the low calibration time while significantly improving the image quality.