In vivo setup characterization for pulsed electromagnetic field exposure at 3 GHz

An in vivo setup for pulsed electric field exposure at 3 GHz is proposed and characterized in this work. The exposure system allows far field, whole-body exposure of six animals placed in Plexiglas cages with a circular antenna. Chronic exposures under 18 W incident average power (1–4 kW peak power) and acute exposures under 56 W incident average power (4.7 kW peak power) were considered. Numerical and experimental dosimetry of the setup allowed the accurate calculation of specific absorption rate (SAR) distributions under various exposure conditions. From rat model numerical simulations, the whole-body mean SAR values were 1.3 W kg⁻¹ under chronic exposures and 4.1 W kg⁻¹ under acute exposure. The brain-averaged SAR value was 1.8 W kg⁻¹ and 5.7 W kg⁻¹ under chronic and acute exposure, respectively. Under acute exposure conditions, a 10 g specific absorption of 1.8  ±  1.1 mJ · kg⁻¹ value was obtained. With temperature rises below 0.8 °C, as measured or simulated on a gel phantom under typical in vivo exposures, this exposure system provides adequate conditions for in vivo experimental investigations under non-thermal conditions. (paper)