[Thermographic analysis of the brain temperature in rats following microwave irradiation]

A thermoviewer, a new model of JTG-500 (JEOL, Japan) was utilized for finding the effect of microwave heat energy absorption and its conductivity in the brains of rats and mice following microwave irradiation (MWR). The frozen head was cut in either the sagittal, frontal or horizontal plane. After the frozen brain returned to room temperature (27-28 degrees C), the parts were put together with scotch tape and place in the exposure chamber. The rat's brain was irradiated at 6 kW for 0.6 sec and the mouse's brain was irradiated at 6 kW for 0.12 sec. Within 2 min. after irradiation, one side of each head was removed from the body and set in front of the camera unit. Each frame of a thermal image with its temperature information was stored in a data memory and the image of the brain surface was displayed at a flickerfree TV rate under the most optimum display condition. The temperature resolution of the device was 0.05 degrees C. In the individual rat planes, the highest energy was efficiently centralized in the middle of each individual plane and was distributed to the periphery showing phased decreases in temperature. The temperature differences recorded in the rat's sagittal, frontal and horizontal sections were; 4.6 degrees C, 5.0 degrees C and 3.4 degrees C, respectively. Temperature differences in rat brains irradiated by MWR were known to be below 5.0 degrees C under these experimental conditions. In the mouse planes, the highest level of microwave energy was also centralized in the middle of each individual section.(ABSTRACT TRUNCATED AT 250 WORDS)