This is a relatively new technology in development that is based on injecting current through surface electrodes into the human body. This current will induce a magnetic flux that relates to the conductivity of the tissue. MRI will then capture this magnetic flux. This technology shows a high resolution within a few millimetres. The SNR (signal to noise ratio) issue still has to be resolved.
I find this technology very interesting as an adjunct to EEG. During EEG the electrical activity of the brain is captured at the surface of the scalp. Differences in brain conductivity can alter the EEG recordings. MREIT can help refine EEG source localization by giving information on the brain conductivity by region. Also MREIT could be useful to help understand better the mechanisms behind EEG recordings.
An interesting paper on this topic is the following:
Minhas AS, et al. Experimental Performance Evaluation of Multi-Echo ICNE Pulse Sequence in Magnetic Resonance Electrical Impedance Tomography. Magnetic Resonance in Medicine (2011) 66: 957-865
Adolfo Cotter, MD