Electrical impedance tomography using lorentz fields

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2012

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Zengin, Reyhan

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In this thesis, a novel approach is proposed to image the electrical conductivity properties of biological tissues. This technique is based on electrical current induction using ultrasound together with and applied static magnetic field. Acoustic vibrations are generated via piezoelectric transducers located on the surface of a biological body. To simulate the new technique multiphysics solution is required which couples pressure and electromagnetic equations. The feasibility of the proposed approach is investigated using analytical and numerical techniques. A linear phased array piezoelectric transducer and a single element transducer are used to form pressure distribution in human body/tissue. In the existence of a static magnetic field, the resultant (velocity) current density is sensed by a receiver coil encircling the tissue and used for reconstructing the conductivity distribution. To sense the resultant current density a novel coil configuration is proposed. Truncated Singular Value Decomposition (tSVD) Method is used as a reconstruction algorithm. Results show the potential of this approach as a new, practical and high resolution imaging modality for electrical conductivity imaging.

Subject Keywords

Diagnostic imaging., Electric conductivity., Diagnostic ultrasonic imaging., Imaging systems in medicine., Electrical impedance tomography.

URI

http://etd.lib.metu.edu.tr/upload/12619905/index.pdf
https://hdl.handle.net/11511/25583

Collections

Graduate School of Natural and Applied Sciences, Thesis

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Citation Formats

R. Zengin, “Electrical impedance tomography using lorentz fields,” Ph.D. - Doctoral Program, Middle East Technical University, 2012.