Projected Current from One Component of Magnetic Flux Density in MREIT

Abstract

Magnetic resonance current density imaging (MRCDI) provides a current density image by measuring the induced magnetic flux density within the subject using a magnet resonance imaging (MRI) scanner. Magnetic resonance electrical impedance tomography (MREIT) is to visualize the current density and/or conductivity distribution in the subject using measured one component of the magnetic flux density B _z of B. We consider a map T from current density vector field J to one component of magnetic flux density B _z .The map T provides an orthogonal decomposition J=J ^P +J ^N of the current J where J ^N belongs to the null space of the map T. We explicitly describe the projected current density J ^P from measured B _z . The projectedcurrent density J ^P providesa good approximation of the true current J in a real time. Numerical simulations show that J ^P from measured B _z is quite similar to the target J. Biological tissue phantom experiments compare J ^P with the reconstructed J via the reconstructe disotropic conductivity using the harmonic B _z algorithm.