Electrical impedance tomography using the magnetic field generated by injected currents

Date

1996-11-03

Author

Birgul, O
Ider, YZ

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In 2D EIT imaging, the internal distribution of the injected currents generate a magnetic field in the imaging region which can be measured by magnetic resonance imaging techniques. This magnetic field is perpendicular to the imaging region on the imaging region and it can be used in reconstructing the conductivity distribution inside the imaging region. For this purpose, internal current distribution is found using the finite element method. The magnetic fields due to this current is found using Biot-Savart law. Sensitivity of magnetic field distribution to inner conductivity perturbations for different current injection profiles is studied. it is found that, to achieve a uniform spatial resolution, a current profile which generates uniform current inside the imaging region is to be applied. The condition number of the sensitivity matrix obtained for this case is found to be very low. Several images are obtained using simulation data.

Subject Keywords

Impedance, Tomography, Magnetic fields, Magnetic field measurement, Magnetic resonance imaging, Conductivity, Current measurement, Current measurement, Current distribution, Finite element methods

URI

https://hdl.handle.net/11511/65115

Conference Name

18th Annual International Conference of IEEE Engineering-in-Medicine-amd-Biology-Society

Collections

Department of Electrical and Electronics Engineering, Conference / Seminar

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Citation Formats

O. Birgul and Y. Ider, “Electrical impedance tomography using the magnetic field generated by injected currents,” Amsterdam, Netherlands, 1996, vol. 18, p. 784, Accessed: 00, 2020. [Online]. Available: https://hdl.handle.net/11511/65115.