Age-related changes of electrical conductivity in adults: preliminary results with MR-EPT

Motivation: Age-related study of electrical conductivity may be useful for personalized SAR modelling. Goal(s): To evaluate in-vivo conductivity changes in a preliminary study in adults (brain and liver), using MR Electrical Properties Tomography, at 3T. Approach: We used a UTE sequence to obtain RF-weighted images suitable for conductivity reconstruction. Data from 10 subjects were analyzed: in the brain, white matter and grey matter values were quantified; in the liver, fat volume fraction was also obtained for comparison. Results: In-vivo conductivities were close to literature values, except for white matter which was higher in vivo. A significant dependency with age was found in the liver. Impact: Knowledge of electrical properties of tissues is required for SAR modelling. Currently, values from ex-vivo/animal studies are used. In-vivo measurements by MR-EPT could bring valuable insights, in particular age-related changes, if existing, could be considered for MRI safety studies.