Thermo-vibrational analyses of skin tissue subjected to laser heating source in thermal therapy

Mina Ghanbari,Ghader Rezazadeh

doi:10.1038/s41598-021-02006-7

Abstract

Laser-induced thermal therapy, due to its applications in various clinical treatments, has become an efficient alternative, especially for skin ablation. In this work, the two-dimensional thermomechanical response of skin tissue subjected to different types of thermal loading is investigated. Considering the thermoelastic coupling term, the two-dimensional differential equation of heat conduction in the skin tissue based on the Cattaneo–Vernotte heat conduction law is presented. The two-dimensional differential equation of the tissue displacement coupled with the two-dimensional hyperbolic heat conduction equation in the tissue is solved simultaneously to analyze the thermal and mechanical response of the skin tissue. The existence of mixed complicated boundary conditions makes the problem so complex and intricate. The Galerkin-based reduced-order model has been utilized to solve the two-sided coupled differential equations of vibration and heat transfer in the tissue with accompanying complicated boundary conditions. The effect of various types of heating sources such as thermal shock, single and repetitive pulses, repeating sequence stairs, ramp-type, and harmonic-type heating, on the thermomechanical response of the tissue is investigated. The temperature distribution in the tissue along depth and radial direction is also presented. The transient temperature and displacement response of tissue considering different relaxation times are studied, and the results are discussed in detail.

Highlights

Laser-induced thermal therapy, due to its applications in various clinical treatments, has become an efficient alternative, especially for skin ablation
Hyperthermia can be categorized into long-term low-temperature hyperthermia in which the tissue temperature rises to 40–41 °C for 6–72 h and moderate-temperature hyperthermia in which tissue experiences 42–45 °C for 15–60 min
As the energy is divided into fractions, deep dermal penetration of the energy is achieved with minimal effect on the epidermis

Summary

Introduction

Laser-induced thermal therapy, due to its applications in various clinical treatments, has become an efficient alternative, especially for skin ablation. Temperature distribution and the process of heating transfer and in living tissues play an important role in the effectiveness of thermal therapy methods. Several bioheat equations have been reported for modeling heat transfer in living tissue.

Results

Conclusion