Numerical Simulation of the Cryosurgery Process Basing on Arm Layered Model with Major Blood Vessels

Abstract

Basing on the tissue structure of the human arm in regional anatomy, a new threedimensional thermal model of the human arm with the major artery and veins was built. The arm model was divided into four layers due to the difference of physical parameters. Liquid nitrogen (76K) was chosen for the cold source. This paper described the specific heat and the coefficient of thermal conductivity as the linear function of temperature and set up the influence of dependent blood perfusion rate and metabolic heat generation on temperature and the major blood vessels flowing during the biological tissue heat transfer of the cryosurgical process. The finite element analysis method was used to study the thermal gradient field when cold sources are distributed in different coordinates and transient thermal field. This paper predicted the radius of ice sphere and phase boundaries during the freezing process in different location of the cryoprobes, and compared the results whether considering the dependence of temperature or not. The influence of the major blood vessels flowing for the arm tissue thermal gradient field was studied meanwhile.