To describe the complex nonlinear process of laser tissue interactions, a two-dimensional mathematical model considering the dynamic changes in the physical tissue properties was developed here. A modified Monte Carlo method was developed to simulate photon transport in the tissue with a non-uniform optical property field. The finite volume method was used to numerically solve the Pennes bioheat equation to calculate the temperature distribution,and the Arrhenius equation was used to predict the thermal damage extent. The numerical results show that the dynamic changes in the optical properties, thermal properties and blood perfusion rate significantly affect the damage volume accumulation history in tissue and should be included in numerical simulations of the LITT treatment.