Equipotential projection based magnetic resonance electrical impedance tomography (mr-eit) for high resolution conductivity imaging

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2003

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Özdemir, Mahir Sinan

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In this study, a direct reconstruction algorithm for Magnetic Resonance Electrical Impedance Tomography (MR-EIT) is proposed and experimentally implemented for high resolution true conductivity imaging. In MR-EIT, elec trical impedance tomography (EIT) and magnetic resonance imaging (MRI) are combined together. Current density measurements are obtained making use of Magnetic Resonance Current Density Imaging (MR-CDI) techniques and peripheral potential measurements are determined using conventional EIT techniques. 0.15 Tesla METU MRI system is used for MR-EIT technique and opposite DC current injection method is adopted for MR-CDI technique. The fast, non-iterative image reconstruction algorithm used in reconstructing inte rior conductivity distribution is based on the fact that equip otential lines are perperdicular to current vectors. The suggested method is tested on both sim ulated and experimental data for conductor and insulator objects and results are presented. In the simulation results, error in the reconstructed conductiv ity is found to be between 12.4%-13.9% for background and 22.4%-32.9% for the object. The spatial resolution is space independent and is limited by twice, the MRI pixel size. It is shown that the proposed technique can be used to re construct conductivity images with high resolution and accurate conductivity.

Subject Keywords

Electrical impedance tomography, Electrical impedance tomography, Magnetic resonance imaging, Current density imaging

URI

https://hdl.handle.net/11511/13637

Collections

Graduate School of Natural and Applied Sciences, Thesis

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Citation Formats

M. S. Özdemir, “Equipotential projection based magnetic resonance electrical impedance tomography (mr-eit) for high resolution conductivity imaging ,” M.S. - Master of Science, Middle East Technical University, 2003.