Patent ID: 6397095
Filing Date: 2002-05-28
Classification: G01R

Abstract:
A method of performing electrical impedance tomography of an object using magnetic resonance (MR), comprising the steps of:imaging a current density of said object by performing the steps of placing a series of electrodes around said object, placing said object in a magnetic field, applying a current through said electrodes, and applying an MR imaging sequence which is synchronized with the application of current through the electrodes, simultaneously measuring electric potentials of a surface of said object caused by the application of current through the electrodes and an MR imaging signal caused by the MR imaging sequence; processing the MR imaging signal to calculate an internal impedance of said object, said MR signal containing information about the current and the measured potential from which to determine said internal impedance; and determining a local impedance of the object by performing the steps of mapping the current density for a particular pair of electrodes, determining equi-potential lines using said measured electric potentials, said equi-potential lines representing an area with a constant potential and being substantially perpendicular to current density lines of said object in said magnetic field, and calculating a gradient of electrical potential from the equi-potentials.