LASER RADIATION PROPAGATION AND HEAT TRANSFER INTO CELLS AND TISSUES

In this paper we shall approach only the interaction of laser radiations with highly scattering and/or absorbing biological materials (i.e., opaque materials). The photon multiple scattering by cells and tissues is approached from the perspective of the general propagation theory (i.e., simple diffusion) of a particular physical magnitude, provoked by its conjugated gradient. In this way, one can obtain, in a particular case, the analytic expression of fluence rate for the isotropic tissues. The propagation theory is also conducting to the model of heat transfer (i.e., spatial-temporal evolution of the temperature) in the adjacent regions of target in which the laser absorbed energy was converted into heat.