**6. Conclusion**

The present chapter discusses the modeling of the laser-irradiated biological tissue to understand its thermal behavior, which may help improve the efficacy of the laserbased photo-thermal therapy to destroy the cancerous cells with minimal damage to the surrounding healthy tissue. The light propagation through the biological tissue was mathematically modeled using the RTE. The RTE was solved using the DOM to determine the intensity distribution inside the biological tissue subjected to shortpulse laser irradiation. Once the intensity distribution was obtained, the divergence of radiative heat flux was calculated, which acts as the source term in the Fourier/non-Fourier model-based bio-heat transfer equation to determine the temperature distribution inside the laser-irradiated biological tissue. However, it is a multi-time scale problem because of the two different time scales used to solve the RTE and bio-heat transfer equation. So, the algorithm for solving this multi-time scale was presented. The non-Fourier model-based bio-heat transfer equation was numerically solved using the FVM to determine the temperature distribution. The numerical results were compared with the analytical results obtained using the FIT technique and found that the numerical solution predicted relatively lower temperature values than the analytical solution. A comparative study between the Fourier and non-Fourier (C-V and DPL) models was conducted and found that the temperature predicted using the DPL model lies between the C-V and Fourier models.
