Cryosurgical probe for large area cooling

Abstract

Cryosurgical probe is a device to destroy detrimental biological tissue by utilizing low temperature which is typically obtained from J-T (Joule-Thomson) expansion process. When a malignant tissue is developed in a small region of prostate, kidney, or lung cancer, the cryosurgical probe is better designed to have a focused cooling effect at its tip. On the other hand, it can be designed to possess a long cooling area when the cooling target forms into a long cylindrical shape like varicose vein. In this research, the cryostripping probe which can be potentially useful for varicose vein has been developed. The cryostripping probe is designed to have uniform cooling capacity over the probe length of 20 cm using multiple heat exchanger and multiple expansion parts. The developed cryostripping device is fabricated as the cylindrical shape with 6.3mm outside diameter and its cooling characteristic is experimentally investigated. The detailed ice ball pattern and growth rate are examined when the probe is operated with 50 bar nitrous oxide gas.