Lattice Boltzmann method based computations for gold nanorods mediated thermal ablation during plasmonic photothermal therapy

Use of lattice Boltzmann method (LBM) is gaining importance for solving thermal transport within biological tissue during thermal therapy such as plasmonic photothermal therapy (PPTT) due to its advantages like parallel computation, high scalability, ease of solving complex boundaries etc. over conventional numerical techniques. Commonly, during PPTT, near infrared (NIR) irradiation is used for a tumor embedded with nanoparticles having plasmon response in NIR wavelength range. Gold nanorods (GNRs), due to their biocompatibility and having plasmon response in NIR band, are widely considered nanoparticle during PPTT. LBM provides advantages of real time computing and faster computations. Herein, D3Q15 scheme of LBM is reported to solve thermal transport using Pennes' bioheat model and thermal ablation using Arrhenius equation within a 3D tumor-tissue domain during PPTT involving GNRs and on NIR irradiation. The absorption of incident irradiation by GNRs is calculated using Beer-Lambert's law. The temperature obtained by the proposed 3D algorithm of LBM is first validated with the finite element method. Then, the effects of GNRs concentration and irradiation intensity are computed which reveal that higher GNR concentrations leads to higher surface temperature while lower concentrations provide more uniform temperature profile within whole of the tumor. This study suggests that LBM is useful for pre-treatment planning of PPTT for faster computations.