Cryogenic Treatment of the Common Wart

Abstract

This study models the effect of applying subzero temperature liquids to the surface of a common wart. The goal was to determine which variables (i.e. conductivity of skin, temperature of liquid, duration of application) that affected the extent of wart death versus healthy skin damage and to maximize this ratio. The wart was analyzed as an axi-symmetric, isotropic solid that protrudes from the skin surface. GAMBIT was used to create the mesh of skin and wart, and FIDAP was used to conduct finite element analysis to model the freezing process. Our results showed that liquid nitrogen was the most effective agent for cryogenic treatment of warts. The application time that resulted in maximal wart death and minimal skin damage was nine seconds with liquid nitrogen. In addition, sensitivity analyses were performed to determine the impact of changes in parameters and properties. The bioheat term and changes in the heat transfer coefficient did not significantly affect the results. However, a thermal conductivity that varied with temperature produced significantly different results compared to a constant conductivity.