Conductivity imaging of canine body using 3T magnetic resonance electrical impedance tomography (MREIT) system

Magnetic Resonance Electrical Impedance Tomography (MREIT) aims to produce cross-sectional images of conductivity distributions inside animal and human subjects. In this study, we validate its feasibility by performing conductivity imaging experiments of post-mortem canine bodies. After clipping the hair of a beagle, we attached four carbon–hydrogel electrodes and placed the dog inside our 3T MRI scanner. We injected the imaging current in the form of short pulses into the imaging area, the timing of which was synchronized with a chosen pulse sequence. By obtaining images of the induced magnetic flux density distributions inside the dog, we reconstructed conductivity images using the single-step harmonic BzBz algorithm based on the relationship between conductivity and magnetic flux density. Reconstructed conductivity images of heart, kidney, prostate, and other organs exhibited unique contrast information hardly observed in other imaging modalities. By providing cross-sectional conductivity images with a spatial resolution of a few millimeters, MREIT may deliver unique new diagnostic information in future clinical studies.