RF/microwaves in bio-medical applications

Paper presents the heating effects of microwaves in biomedical applications. Heat treatment is used in physiotherapy department to deal with pain, muscle spasm stiffness and chromic inflammation. The heat may be applied by conduction through the skin or diathermy may be used. One form of diathermy employs microwaves directed at the region to be treated from an antenna placed at a short distance (10 or 20 cm) from the skin. The waves will pass a few centimetres into the body before they are completely absorbed and realizing heats into the tissue. The used frequency is 2450 MHz at which penetration may be up to 30 mm. The size of the area to be treated can be determined by the antennae design and the distance from the body. A response rate of 60% from combining microwave hyperthermia and radiotherapy compared with 30% for radiotherapy alone has been seen earlier.