High resolution imaging of anisotropic conductivity with magnetic resonance electrical impedance tomography (mr-eit)

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2010

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Değirmenci, Evren

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Electrical conductivity of biological tissues is a distinctive property which differs among tissues. It also varies according to the physiological and pathological state of tissues. Furthermore, in order to solve the bioelectric field problems accurately, electrical conductivity information is essential. Magnetic Resonance Electrical Impedance Tomography (MREIT) technique is proposed to image this information with high spatial resolution. However, almost all MREIT algorithms proposed to date assumes isotropic conductivity in order to simplify the underlying mathematics. But it is known that most of the tissues in human body have anisotropic conductivity values. The aim of this study is to reconstruct anisotropic conductivity images with MREIT. In the study, five novel anisotropic conductivity reconstruction algorithms are developed and implemented. Proposed algorithms are grouped into two: current density based reconstruction algorithms (Type-I) and magnetic flux density based algorithms (Type-II). Performances of the algorithms are evaluated in several aspects and compared with each other. The technique is experimentally realized using 0.15T METU – EE MRI System and anisotropic conductivity images of test phantoms are reconstructed using all proposed algorithms.

Subject Keywords

Electrical engineering.

URI

http://etd.lib.metu.edu.tr/upload/3/12611982/index.pdf
https://hdl.handle.net/11511/19756

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Graduate School of Natural and Applied Sciences, Thesis

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Citation Formats

E. Değirmenci, “High resolution imaging of anisotropic conductivity with magnetic resonance electrical impedance tomography (mr-eit),” Ph.D. - Doctoral Program, Middle East Technical University, 2010.