2D Magnetic Resonance Electrical Property Tomography based on B1− field mapping

Magnetic Resonance Electrical Property Tomography (MREPT) is a method to visualize electrical conductivity and permittivity distributions in the object. Traditional MREPT relies on either the radio frequency (RF) transmit field (B+1) mapping, or using a transmit/receive RF coil, to compute tissue's electrical conductivity and permittivity. This paper introduces an alternative approach based on the reconstructed receive field (B-1) By solving a system of homogeneous equations consisting of the signal ratios from multi-channel receive coils, the receive field distribution with both magnitude and phase can be computed. Similar to (B+1) based MREPT method, the conductivity and permittivity in the imaging object can be calculated from the (B-1) field. We demonstrated the feasibility to image electrical property contrasts through computer simulated studies and phantom experiments. Although this study focuses on the 2D reconstruction, the presented method can be extended to full 3D. This method can be applied to regular MR imaging collected with multi-channel receive coils, and therefore, tissue anomaly based on electrical properties can potentially be revealed with a higher imaging quality, providing useful information for clinical diagnosis.