Physical considerations in using thermal techniques for the delineation of radiation damage in skin

In irradiated skin, damage occurs not only to the skin but also to the vasculature transporting blood to and from the skin. Since heat is transported from the body core to the periphery of the body by the blood as well as by direct transmission, a decreased rate of heat transfer to the skin should occur in persons receiving a significant dose of radiation. The physical considerations of this change in the vasculature, with the skin at thermal equilibrium and non-equilibrium conditions, were explored and the hypothesis tested. A temperature mapping of the irradiated and non-irradiated skin of patients previously treated for carcinoma of the cervix was performed using a cholesterol ester liquid crystal device (Rhochrome^R). The results show that, in only one patient, was there sufficient damage to give a thermal difference between irradiated and non-irradiated skin at equilibrium conditions. In other patients, however, a thermal difference was seen following a thermal shock. An analysis of the physical considerations was discussed, along with the detailed results of the procedure.