Conductivity and current density image reconstruction in MREIT using harmonic Bz algorithm and recessed electrodes

This paper presents cross-sectional conductivity and current density images of an inhomogeneous saline phantom. Using a 0.3 Tesla MRI scanner with its main magnetic field in the z-direction, we measured the z-component of the induced magnetic flux density B_z, due to multiple injection currents. Four recessed electrodes are used to inject six different currents without producing artifacts near the boundary of the imaging subject. We used an image reconstruction algorithm calledΔ²B_z, algorithm to reconstruct images with a spatial resolution of 82×82 pixels (0.6×0.6 mm²/pixel). The accuracy of the reconstructed image was estimated as 13.8 to 21.5% in terms of the relative L²-error over all pixels.