Experimental Analysis and Computational Modeling of Agarose Phantoms for Photothermal Laser Ablation

Water-agarose phantom can approximate the thermal behavior of human soft tissue, and it is widely used in medicine to mimic the thermal response for various techniques. Specifically, photothermal therapy uses light energy to damage cancerous tissues. Gold nanoparticles can be injected into the tumor region to enhance the treatment efficacy. Accurate modeling of temperature distributions is essential for treatment safety and planning. This work aims to study the temperature distribution of an agarose phantom irradiated by a near-infrared (NIR) laser source by combining an experimental-modeling study. The experimental set-up consisted of an accurate temperature measurement conducted using Fiber Bragg Grating sensors. The computational model was implemented to replicate and better understand the involved phenomena. In particular, laser light propagation and agarose thermal response were reproduced via an optical diffusion model and Pennes' bioheat equation. A comparison between experimental and simulated outcomes demonstrated the reproducibility of the novel set-up and the predictivity of the fine-tuned model.