Accuracy improvement of wireless temperature technique by rotary scan for hyperthermia using ferromagnetic implant

Soft-heating method is one type of hyperthermia that necrotizes malignant tumors in cancer treatment by means of heat generated by a ferromagnetic material. The magnetic permeability of ferromagnetic particle decreases immediately when its temperature increases over the Curie point (43°C). Therefore, we can concurrently use the ferromagnetic particles as a thermal probe for wireless temperature measurement during hyperthermia treatment. A challenge remains when dealing with body movement artifact as the relative position between the detection coil and the material is fluctuated by breathing or beating of the heart. As a result, the accuracy of temperature detection decreases. In this report we suggest and verify the validity of the new inspection system for the body movement artifact removal by regularly circling a unit of the magnetic field supply coil and the detection coil around the upper surface of the tumor region.