Measurement of electric current density with magnetic resonance imaging

Results of a magnetic resonance imaging (MRI) study to image uniform and nonuniform electric current density are presented. Current density in a volume conductor, containing magnetic resonance active nuclei, can be imaged using MRI. A standard spin echo pulse sequence is used, simultaneously with a bipolar current pulse. The flux density, parallel to the main imaging field, generated by the current pulse is encoded in the phase of the complex MR image. The spatial distribution of magnetic flux density can therefore be extracted from the phase image. Current density is calculated from the magnetic flux density