International Journal on Magnetic Particle Imaging IJMPI
Vol. 10 No. 1 Suppl 1 (2024): Int J Mag Part Imag

Proceedings Articles

Multicontrasting MPS by dual-tone nonlinearity probing

Main Article Content

Timur Bikulov (Forschungszentrum Jülich), Faranak Eivazi , Prof. Dr. Andreas Offenhäusser (Institute of Biological Information Processing, Forschungszentrum Jülich, 52425 Jülich, Germany), Prof. Dr. Hans-Joachim Krause  (Institute of Biological Information Processing, Forschungszentrum Jülich, 52425 Jülich, Germany)


Novel MPI-based modalities such as multi-contrast imaging or remote viscosity recording require independent measurement of at least two or more magnetic particle types simultaneously. Particle response models based on the Fokker-Plank equation allow independent reconstruction of core and hydrodynamic diameters. However, due to complexity and stochastic character, they remain a black box for explaining the origin of measured nonlinear distortions. A model is required to suggest which frequency lines to measure, which fields to apply for reconstruction of particle core size distribution, and to explicitly show limitations of setup and measurement scheme (e.g., the range of core diameters available for reconstruction). Assuming that the amplitude of the sample magnetic moment and its distortions are determined by the number of excited magnetic moments, and response phase is governed by amplitude-dependent relaxation mechanisms, we show how and under what conditions two-tone systems become the key to independent measurement of the response from particles of different diameters.

Article Details


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