Print Email Facebook Twitter Multiplicative contrast source inversion method in electrical properties tomography based on Jacobi matrix inversion Title Multiplicative contrast source inversion method in electrical properties tomography based on Jacobi matrix inversion Author Helfferich, Florens (TU Delft Electrical Engineering, Mathematics and Computer Science; TU Delft Signal Processing Systems) Contributor Remis, R.F. (mentor) Kooij, B.J. (graduation committee) Degree granting institution Delft University of Technology Programme Electrical Engineering | Signals and Systems Date 2024-04-05 Abstract The tissue electrical properties of conductivity and permittivity affect the interactions of electromagnetic fields in the body. These properties vary throughout the different tissues as the tissue structure and composition varies. In this thesis, medical imaging and diagnosis is used as primary example to motivate exploration of a novel regularization approach to an MRI-based electrical properties tomography (EPT) method. Total variation (TV) regularization has been shown to perform noise reduction in the iterative Contrast Source Inversion EPT (CSI-EPT) method. The Jacobi matrix inversion regularization, an alternative to the known conjugate gradient formulation, is elaborated and applied to an E-polarized MRI fields scenario such that this thesis presents the Jacobi step regularized CSI-EPT. The alternative regularization method outperforms the known regularization method in the reconstruction qualities of noise-suppression and edge-preservation in the simulated MRI experiments using a virtual body model. Further advancements are also described, such as multiple inner-iterations Jacobi regularization and an anatomical prior initialization of the contrast function. Important future research topics are the incorporation and evaluation of the Jacobi step regularization into more advanced CSI-EPT versions, which are the three-dimensional and transceive phase based algorithms to correct realistic MRI data. Subject ImagingMRIElectrical Property TomographyRegularizationcontrast source inversion To reference this document use: http://resolver.tudelft.nl/uuid:0f05d52f-3b1a-4bf5-b234-8f943b4192f6 Part of collection Student theses Document type master thesis Rights © 2024 Florens Helfferich Files PDF MSc_Thesis_Florens_Helfferich.pdf 7.39 MB Close viewer /islandora/object/uuid:0f05d52f-3b1a-4bf5-b234-8f943b4192f6/datastream/OBJ/view