Identification of current density distribution in electrically conducting subject with anisotropic conductivity distribution

• Published in: Physics in medicine & biology Vol. 50; no. 13; pp. 3183 - 3196
• Main Authors: Pyo, Hyun Chan, Kwon, Ohin, Seo, Jin Keun, Woo, Eung Je
• Format: Journal Article
• Language: English
• Published: England IOP Publishing 07.07.2005
• Subjects: Algorithms; Anisotropy; Computer Simulation; Electric Conductivity; Image Enhancement - methods; Image Interpretation, Computer-Assisted - methods; Information Storage and Retrieval - methods; Magnetic Resonance Imaging - methods; Models, Biological; Plethysmography, Impedance - methods; Scattering, Radiation
• ISSN: 0031-9155; 1361-6560
• DOI: 10.1088/0031-9155/50/13/015

Current density imaging (CDI) is able to visualize a three-dimensional current density distribution J inside an electrically conducting subject caused by an externally applied current. CDI may use a magnetic resonance imaging (MRI) scanner to measure the induced magnetic flux density B and compute J via the Ampere law [Formula: see text]. However, measuring all three components of B = (B(x), B(y), B(z)) has a technical difficulty due to the requirement of orthogonal rotations of the subject inside the MRI scanner. In this work, we propose a new method of reconstructing a current density image using only B(z) data so that we can avoid the subject rotation procedure. The method utilizes an auxiliary injection current to compensate the missing information of B(x) and B(y). The major advantage of the method is its applicability to a subject with an anisotropic conductivity distribution. Numerical experiments show the feasibility of the new technique.