Numerical Simulation of Thermal Distribution in a Multi-Layer Biological Tissue (Epidermis–Dermis–Fat) Exposed to a Gaussian-Shaped Pulsed YAG Laser Using Pennes’ Bioheat Transfer Equation
Keywords:
Laser physics, medical laser, heat distribution, Nd:YAG laser, skin, Gaussian pulse, numerical simulation, Pennes equationAbstract
This paper presents the development of an advanced numerical model to study the thermal distribution in a multilayer biological tissue — consisting of the epidermis, dermis, and subcutaneous fat — when exposed to a Gaussian-shaped pulsed Nd:YAG laser in both time and space. The model is based on the formulation of the Pennes bio-heat transfer equation, taking into account the thermal and optical properties of each layer individually, including the absorption coefficient, thermal conductivity, density, and specific heat capacity.
The simulation was implemented using the finite difference method to simulate the temporal and spatial evolution of temperature within the tissue under short pulse durations (less than one second) with a non-uniform energy distribution. The results demonstrated dynamic thermal behavior consistent with the theoretical laser pulse distribution, and the outcomes were presented in colored graphical form to enable a deeper visual understanding of the heat propagation mechanism within the tissue.
This study opens new prospects for applying precise thermal simulations to enhance the effectiveness of medical laser treatments, providing predictive insight into the thermal effects on the skin and helping to minimize undesirable damage to adjacent tissues
References
H. H. Pennes, "Analysis of tissue and arterial blood temperatures in the resting human forearm," Journal of Applied Physiology, vol. 1, no. 2, pp. 93–122, 1948.
A. J. Welch and M. J. C. van Gemert, Optical-Thermal Response of Laser-Irradiated Tissue, 2nd ed., New York: Springer, 2011.
X. Xu, L. Zhu, and Z. Guo, "Numerical investigation on photothermal interaction between short-pulsed laser and tissues," International Journal of Heat and Mass Transfer, vol. 45, no. 15, pp. 3163–3172, 2002.
H. Y. Huang and D. Y. Tzou, "Evaluation of thermal damage in living biological tissues subjected to laser heating," Applied Thermal Engineering, vol. 21, no. 15, pp. 1441–1461, 2001.
L. Jia and J. Liu, "Modeling of temperature distribution in multilayer biological tissue irradiated by laser with a pulse duration," Journal of Biomedical Optics, vol. 21, no. 10, p. 105002, 2016.
M. S. Arif and T. Latif, "Numerical simulation of temperature distribution in multi-layer skin tissue induced by short-pulsed laser," Biomedical Engineering Letters, vol. 8, no. 4, pp. 417–425, 2018.
E. Majchrzak and B. Mochnacki, "Modelling of laser ablation process using the boundary element method," Computer Assisted Mechanics and Engineering Sciences, vol. 19, no. 1, pp. 15–23, 2012.
H. M. Al-Qahtani, "Laser–tissue interaction modeling and simulation using bioheat equation," Saudi Journal of Biological Sciences, vol. 27, no. 1, pp. 70–75, 2020.
M. A. Alwan and A. A. Hadi, "A Numerical Study of Laser Effect on Biological Tissues by Using Pennes Bio-Heat Equation," Iraqi Journal of Physics, vol. 20, no. 1, pp. 29–37, 2022.
