The effect of dynamic optical properties on the spatial distribution of light in laser therapy is studied via numerical simulations. Laser light transport is simulated with a Monte Carlo technique including anisotropic scattering and absorption. Thermal heat transport is calculated with a finite difference algorithm. Material properties are specified on a 2D mesh and can be arbitrary functions of space and time. Arrhenius rate equations are solved for tissue damage caused by elevated temperatures.
Optical properties are functions of tissue damage, as determined by previous measurements.
Results are presented for the time variation of the light distribution and damage within the tissue as the optical properties of the tissue are altered.