抄録
Cryosurgical system utilizing liquid nitrogen and argon gas as cryogens has been used for the treatment of malignant tumors. Those devices fail to cool the tissues to the low temperatures that completely destroy the bulky tumors. It is of course difficult for the low power cooling devices using Peltier effect, to destroy the large tumors. Therefore adjunctive treatment such as hyperthermia treatment is needed to intensify the tissue destruction. Actually, hyperthermia has been clinically used to destroy tumors, but it is unclear that the hyperthermia enhances the tissue injury in cryosurgery because there have been few studies of the combination use of hyperthermia and cryosurgery. The purposes of this study are to produce the cryosurgery-hyperthermia treatment system utilizing Peltier device and Stirling cooler and to evaluate the effects of hyperthermia treatment immediately after thawing in cryosurgery onto the living normal liver tissue of mouse. In the no-load running test of our system, the minimum temperature of the cryoprobe reached -74.0 degrees C in 30 minutes. The findings of the stained tissues suggested that the combination treatment of both was effective to destroy the tissue and the higher temperature applied immediately after freezing and thawing in cryosurgery might reinforce the tissue destruction.
