Further Evaluation of Heating by Microwaves and by Infrared as Used Clinically

Although a number of basic studies of the heating effects of infrared energy and diathermy have been made, there still remains considerable confusion regarding the comparative effectiveness of various sources of heat on human tissue. Infrared energy for radiant heating has been used for many years. The infrared generators are safe, simple to use, and inexpensive and are known to provide effective heating of at least the more superficial tissues. During the last 25 years physicians have followed with interest the development of various types of generators of high-frequency electromagnetic energy (diathermy equipment) for heating tissues at relatively greater depths than can be effectively heated with infrared. Diathermy machines have been expensive, more difficult to use, and, if improperly used, fraught with some danger of burns and discomfort. Since it has been shown that the temperature in muscular tissue can be raised significantly with a 20 minute application of infrared