Multiple beam scattering effects in biological tissues exposed to laser radiation

A mathematical model is presented for the computation of intensity of radiation in biological tissues irradiated by laser. The time-independent transport radiative equation is solved in terms of a Neumann series. Each term of the series is associated with a different order of magnitude of the internal-scattering effect. The importance of these effects has been recognized during the irradiation by ion-argon and ND: YAG laser used as coagulting or cutting instruments in surgery applications. Agreement is found with the single-scattering picture.