Thermometry studies of radio-frequency induced hyperthermia on hydrogel based neck phantoms.

A cylindrical phantom, resembling average human neck, was prepared by using hydrogel sheets containing vinyl and polysaccharide. The phantom was used to obtain temperature distributions for 6 values of input power of radio frequency (RF) at 8MHz,by invasive thermometry technique, using thermistor probes. The inclusion of cervical vertebrae and calcium carbonate pieces (human bone representative) with a hollow tube (windpipe equivalent) in the phantom simulates the change in thermal distributions. This is similar to the alterations in heat disposition obtained in the real human neck, during RF induced heating, without extensive distortion of the uniform temperature distribution provided by the RF heating instrument. This paper compares the hydrogel neck phantom with other phantoms, that have been developed for studying thermal distributions and optimization of novel non invasive thermometry techniques in hyperthermic oncology.