Thermomechanical analysis of a triple layered skin structure in presence of nanoparticle embedding multi-level blood vessels

Concerning a target-specific malignant cell damage sparing healthy tissue, the advancements in laser and nanotechnology are one of the recent challenges in non-invasive cancer treatment processes. In addition, proper assessment of nociceptive pain induced in the ablation process by simulating the tissue thermomechanical response in a more realistic situation is a useful step prior to real clinical practice. In the present study a nanoparticle infused lesion in a 3-D triple-layered healthy skin structure embedding thermally significant multi-level small arteries and veins is chosen as the computational domain. Dual-phase-lag (DPL) and Pennes bioheat model coupled with equilibrium equations are solved using COMSOL Multiphysics (Bangalore, India) to compute the thermal and mechanical fields in the tissue. An in-vitro temperature measurement of laser irradiated agar-based tissue phantom is also performed to validate the predicted temperature. The aim is to develop a comparative analysis between Intravenous (IV) and Intratumoral (IT) infusion schemes of nanoparticles in terms of precise and uniform necrosis achieved along with stress, strain, and deformation induced in tissue during laser therapy. Numerical results show that the IT scheme offers a useful outcome in terms of precise tumor ablation with minimum thermally induced skin deformation in comparison to the IV scheme. Additionally, the DPL model predicts a more realistic temperature profile along with the induced tissue mechanical response in contrast to the Pennes bioheat model. Most importantly, the small veins have comparatively lower cooling effects than the small arteries in the composite skin structure. Nevertheless, the present study can improve the pre-operational computational modeling of the tissue damage and the nociceptive pain involved during laser therapy prior to clinical application.