Optical-thermal simulation of tonsillar tissue irradiation

Background and Objective: Despite laser applications targetted toward tonsi llar tissue, there has been no characterization of underlying optical and t hermal events during laser irradiation of tonsillar tissue. Study Design/Materials and Methods: The optical properties of canine and hu man tonsils were determined at 805 nm (diode laser) and 1,064 nm (Nd:YAG la ser). An optical-thermal simulation was developed to predict the temperatur e rise in irradiated human tonsils. Results: The optical properties of human and canine tonsillar tissue are si milar at both wavelengths. The optical-thermal simulation was validated and predicts that at 10 W and 1 minute of irradiation, the heat will be contai ned within the human tonsil. The diode laser causes more superficial heatin g than the Nd:YAG laser. Conclusions: The safety of irradiating human tonsils was shown. The diode l aser is superior to the Nd:YAG laser because less heat affects collateral s tructures. The optical-thermal simulation detailed in this study can be use d to predict the temperature rise in tissues undergoing irradiation. Lasers Surg. Med. 28:313-319, 2001. (C) 2001 Wiley-Liss, Inc.