In vivo electrical impedance spectroscopy of irradiated muscle tissue

Electrical impedance spectroscopic measurements over the range 1 kHz-1 MHz have been made in vivo in rat muscle exposed to single radiation doses of 50, 70, 90, and 150 Gy. Two electrode impedance measurements were recorded across the semitendonosis and semimembranosis muscle masses in the hind legs of rats prior to irradiation, within 48 hours post-irradiation, and monthly thereafter. Initial results show a dose response of the impedance spectra. Short term radiation effects, including edemic swelling, also appear to be detectable with this technique. Correlation between radiation induced tissue changes and impedance changes is established at a qualitative level. Eventually this technique will be used in combination with electrical impedance tomography to image the entire region of interest