Magnetic resonance conductivity tensor imaging (MRCTİ) at 3 tesla

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2014

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Sadighi, Mehdi

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Electrical conductivity of biological tissues changes with physiological and pathological state of tissue. Therefore, recognizing the changes of the conductivity distribution inside human body, provides unique information about the pathological conditions of internal organs which is not available from other imaging modalities. Magnetic Resonance Electrical Impedance Tomography (MREIT) is an imaging technique to reconstruct the isotropic conductivity distribution of the biological tissues. But most of the biological structures and tissues have anisotropic conductivity. Therefore, Magnetic Resonance Conductivity Tensor Imaging (MRCTI) is proposed to image the anisotropic conductivity distribution. Similar to MREIT technique, MRCTI reconstruction algorithms are grouped into B-based and J-based algorithms. The aim of this study is implementing the MRCTI J-based algorithms to reconstruct the experimental data obtained using a 3 Tesla Magnetic Resonance Imaging (MRI) system. An experimental phantom is designed and manufactured with special properties according to needs of the experiments and the resulted conductivity distributions are compared. Furthermore, a novel hybrid J-based reconstruction algorithm namely, the Anisotropic Hybrid Equipotential Projection (AHEPP) is proposed, and the related simulations and experimental results are given. In addition, performance of the four J-based MRCTI algorithms in reconstruction of the experimental data is evaluated using error measures.

Subject Keywords

Magnetic resonance imaging., Electrical impedance tomography., Tomography., Electric conductivity.

URI

http://etd.lib.metu.edu.tr/upload/12616851/index.pdf
https://hdl.handle.net/11511/23321

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Graduate School of Natural and Applied Sciences, Thesis

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Citation Formats

M. Sadighi, “Magnetic resonance conductivity tensor imaging (MRCTİ) at 3 tesla,” M.S. - Master of Science, Middle East Technical University, 2014.