TY - JOUR
A2 - Katscher, Ulrich
AU - Lee, Joonsung
AU - Song, Yizhuang
AU - Choi, Narae
AU - Cho, Sungmin
AU - Seo, Jin Keun
AU - Kim, Dong-Hyun
PY - 2013
DA - 2013/03/11
TI - Noninvasive Measurement of Conductivity Anisotropy at Larmor Frequency Using MRI
SP - 421619
VL - 2013
AB - Anisotropic electrical properties can be found in biological tissuessuch as muscles and nerves. Conductivity tensor is a simplified model toexpress the effective electrical anisotropic information and depends on the imagingresolution. The determination of the conductivity tensor should be based on Ohm's law. In other words, the measurement of partial information of currentdensity and the electric fields should be made. Since the direct measurements ofthe electric field and the current density are difficult, we use MRI to measure theirpartial information such as B1 map; it measures circulating current density andcirculating electric field. In this work, the ratio of the two circulating fields, termedcirculating admittivity, is proposed as measures of the conductivity anisotropy atLarmor frequency. Given eigenvectors of the conductivity tensor, quantitativemeasurement of the eigenvalues can be achieved from circulating admittivity forspecial tissue models. Without eigenvectors, qualitative information of anisotropystill can be acquired from circulating admittivity. The limitation of the circulatingadmittivity is that at least two components of the magnetic fields should bemeasured to capture anisotropic information.
SN - 1748-670X
UR - https://doi.org/10.1155/2013/421619
DO - 10.1155/2013/421619
JF - Computational and Mathematical Methods in Medicine
PB - Hindawi Publishing Corporation
KW -
ER -