International Journal on Magnetic Particle Imaging IJMPI
Vol 9 No 1 Suppl 1 (2023): Int J Mag Part Imag

Proceedings Articles

Model-based Calibration and Image Reconstruction with Immobilized Nanoparticles

Main Article Content

Hannes Albers  (University of Bremen), Florian Thieben  (University Medical Center Hamburg-Eppendorf), Marija Boberg  (University Medical Center Hamburg-Eppendorf), Konrad Scheffler  (University Medical Center Hamburg-Eppendorf), Tobias Knopp  (University Medical Center Hamburg-Eppendorf), Tobias Kluth  (University of Bremen)


The model-based reconstruction problem is still one of the key challenges in magnetic particle imaging (MPI) when using multi-dimensional Lissajous-type excitations. One aspect, which is often highlighted in the literature, is the magnetization behavior of the magnetic nanoparticles in fluids, which is typically modeled by a coupling of Brown and N\'{e}el rotation mechanisms. Another aspect, which is at least as important as the particle model itself but sometimes treated less prominently, is a very careful calibration of the model input, respectively the scanner parameters such as analog filter and applied magnetic fields. The careful consideration of both aspects is the essential requirement for a proper solution to the model-based problem. In the present work we combine calibrated scanner components with polydisperse particle models for immobilized nanoparticles to derive a model-based system function and an efficient calibration routine. It is experimentally validated on the Bruker preclinical MPI system using 2D Lissjous trajectories.

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