Fast reconstruction algorithm and experiments based on single current injection for three dimensional MREIT

Magnetic resonance electrical impedance tomography (MREIT) is an electrical conductivity tomography which combines magnetic resonance imaging (MRI) and conventional electrical impedance tomography (EIT) together. It can provide the exact geometric information and the internal magnetic flux density of the imaging object, improve the ill-posed condition in conventional EIT and obtain the electrical conductivity distribution images with high resolution. In order to achieve fast reconstruction for MREIT, based on forward and inverse problems, a method was proposed for electrical conductivity reconstruction with only one current injection. Due to single current injection and one component of magnetic flux density measurement, the scanning time can be reduced and the electromagnetic interference induced by the electrodes can also be decreased; the sensitivity algorithm is expanded to three dimensional space, with the sensitivity matrix obtained by semi-analytical method, thus the reconstruction time can be reduced; at last, simulation and phantom experiments were done to verify the proposed reconstruction algorithm. Both simulation results and phantom experiments indicate that, with single current injection, electrical conductivity can be reconstructed with high resolution and high imaging quality. With both scanning and reconstruction time reduced, MREIT is proved to be a promising approach in clinical application.