PROJECT TITLE :

Magnetic-Resonance-Based Electrical Properties Tomography: A Review

ABSTRACT:

Frequency-dependent electrical properties (EPs; conductivity and permittivity) of biological tissues give important diagnostic info (e.g., tumor characterization), and also play an necessary role in quantifying radiofrequency (RF) coil induced specific absorption rate (SAR), which could be a major safety concern in high- and ultrahigh-field magnetic resonance imaging (MRI) applications. Cross-sectional imaging of EPs has been pursued for many years. Recently introduced electrical properties tomography (EPT) approaches utilize the measurable RF magnetic field induced by the RF coil in an MRI system to quantitatively reconstruct the EP distribution in vivo and noninvasively with a spatial resolution of some millimeters or less. This paper reviews the EPT approach from its basic theory in electromagnetism to the state-of-the-art analysis outcomes. Emphasizing on the imaging reconstruction ways rather than experimentation techniques, we review the developed imaging algorithms, validation results in physical phantoms and biological tissues, in addition to their applications in in vivo tumor detection and subject-specific SAR prediction. Challenges for future research also are discussed.