The systems, methods and apparatus of the present invention comprise noninvasive methods of measuring temperature changes and rates of temperature change in selected body tissues and fluids as a result of absorption and/or dissipation of externally applied heat for the purpose of detecting and monitoring disease or dysfunction, and for preparing diagnostic images of the tissues and related areas from such measurements. Some embodiments of the present invention monitor temperatures of heated tissues directly while other embodiments may measure temperatures of tissues which are heated through flow of heated fluid therethrough.