Electrical impedance tomography using induced and injected currents

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1992-01-01
A two-dimensional forward problem formulation is introduced for electrical impedance tomography (EIT) using induced currents. The forward problem is linearised around a certain resistivity distribution and the inverse problem is formulated as a solution of a linear system of equations. Sensitivity of boundary measurements to resistivity variations arc analysed for spatially uniform, linear and quadratic fields. The formulation, however, is suitable for studying the effects of a general magnetic field applied to induce the currents in the conductive object. A similar inverse problem formulation is also developed for EIT using injected currents. Simulation studies are performed by reconstructing images of a simulation distribution using both methods separately with generalised inversion. It is also shown that the derived formulations for the inverse problems of the two methods can be combined to solve a larger set of equations with a greater number of independent measurements.
CLINICAL PHYSICS AND PHYSIOLOGICAL MEASUREMENT

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Citation Formats
N. G. Gençer and M. Kuzuoğlu, “Electrical impedance tomography using induced and injected currents ,” CLINICAL PHYSICS AND PHYSIOLOGICAL MEASUREMENT, pp. 95–99, 1992, Accessed: 00, 2020. [Online]. Available: https://hdl.handle.net/11511/35058.