A Monte Carlo model is described for modeling photo propagation in a scattering medium. The fraction of locally absorbed photons is proportional to the local rate of heat generation in laser-irradiated tissue and the associated distribution of light (fluence rate) is obtained by dividing the rate of heat generation by the local absorption coefficient. Examples of computed distributions of the rate of heat generation are presented for situations where light scattering in tissue is important. The method is applied to analyze treatment of Port Wine Stain and the selection of laser wave-lengths for cyclophotocoagulation.

Issue Section:
Technical Papers
Topics:
Biological tissues, Heat, Lasers, Absorption, Fluence (Radiation measurement), Light scattering, Modeling, Photons, Waves, Electromagnetic scattering, Radiation scattering, Scattering (Physics)
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