Thermal processes under the action of laser radiation pulse on absorbing granules in heterogeneous biotissues

Abstract

Energy absorption, heat transfer and thermodenaturation, as well as thermomechanical processes and vapour generation, under the action of laser radiation pulse on pigmented spherical granules in heterogeneous laminated biotissues are investigated theoretically. A system of equations is formulated and, based on its numerical solution, consideration is given to the formation and dynamics of a vapour blanket originating during the radiation pulse interaction with an absorbing granule in a water-containing biotissue. The values of radiation pulse energy are calculated which give rise to granular and ophthalmoscopically visible thermodenaturation lesions on the retina and to vapour generation on granules in the pigmented epithelium. A comparison and agreement of numerical results with experimental data validate the models and techniques developed.