A method and apparatus for the manipulation and management process of cryogen such that it controls both the fluid body movement as well as internal currents within the cryogen. In one embodiment, a test structure for a semiconductor device includes a winding disposed in at least one conductive material layer of the semiconductor device. Using a detection circuit, a change in the sensed physiologic information, such as a change from reference physiologic information, can be used to identify a candidate previous treatment event.