抄録
Lasers have been utilized extensively for therapeutics and diagnostics in mdicine, like laser-induced hyperthermia and non-invasive measurement of oxygenation state by near-infrared lasers. Temperature rises of laser-irradiated tissues need to be predicted for prevention of thermal injury, where precise temperature control is necessary or higher energy input is desirable. In order to provide the basic data for safety, this report presents the profiles of the absorbed and transmitted energy calculated by the Monte Carlo method, and by use of the resuls the temporal thermal behaviors of an irradiated body are analysed by solving the bioheat transfer equation. The body is assumed to be a sphere of 30mm diameter, having uniform thermophysical and optical properties of living tissues. The results show the effects of the scattering and absorption coefficients on the absorbed energy density and transmitted energy flux. The resultant temperature variations are found to be mainly dependent on the absorption coefficient and the heat transfer to the environment.
