Microwave Thermography. A Method of Detecting Subsurface Thermal Patterns.

摘要

This is a report of preliminary research into the feasibility of applying microwave radiometers to the detection of thermal patterns in the human body which are associated with pathological conditions. The technique may be thought of as the microwave analog of infrared thermography. Microwave thermography involves the measurement of the intensity at microwave frequencies of thermal radiation emitted by the body. However, since body tissue is partly transparent to microwave radiation, the measured temperature corresponds to radiation which originates from a subsurface tissue volume extending from the skin surface to a depth of several centimeters. The ability of microwave thermography to sense subsurface thermal patterns suggests many potential applications in clinical diagnosis, including early detection of breast cancer and cerebrovascular blockage. As with infrared thermography, a temperature 'map' may be constructed which may be examined for patterns indicative of abnormal local heating or cooling. In this report we discuss the principles of the microwave thermographic method, the instrumentation and experimental techniques, and research results based on the laboratory detection of thermal gradients in feline and human tissue. Planned clinical evaluations are also discussed. (Author)