Patent ID: 7047059

Claim:
A method for noninvasive determination of magnetic susceptibility variation in a patient by measuring magnetic susceptibilities of selected tissue of the patient, the method comprising: providing an instrument which includes at least one magnetic sensor, an applied field coil and a current source connected to the applied field coil and means for processing sensed signals from the at least one magnetic sensor; positioning on the patient a flexible bag substantially filled with deformable material having a magnetic susceptibility substantially similar to that of body tissue, said bag being attached to a substantially rigid barrier, the barrier being spaced a predetermined distance from the patient by the material-filled bag, which predetermined distance remains substantially constant during a measuring sequence, the amount of deformable material in the flexible bag remaining constant during a measuring sequence, the instrument being moved with respect to the barrier during the measuring sequence; positioning the instrument external to the patient in proximity to the tissue of interest and adjacent the barrier; supplying the applied field coil with current thereby applying a magnetic field to the tissue of interest; sensing a response from the tissue of interest wit the instrument; and outputting data corresponding to the magnetic susceptibility variation in the tissue.