Optical-thermal simulation of human tonsillar tissue irradiation: clinical implications.

BACKGROUND AND OBJECTIVE: Mucosa intact laser tonsillar ablation is an alternative to conventional tonsillectomy. The efficacy of this procedure was demonstrated in canines, but establishing the safety of irradiating human tonsils is paramount. STUDY DESIGN/MATERIALS AND METHODS: An optical-thermal simulation of tonsillar tissue irradiation was previously developed, but the effect of varying parameters was not investigated. The tissue response to irradiation at 5-25 watts for 1 minute and 10 watts for 10 seconds to 162 seconds is simulated. RESULTS: At 15 watts and greater, the peak temperature is over 100 degrees C and the mucosal temperature is over 70 degrees C. At the depth of the tonsil, the temperature does not vary significantly. The peak temperature is at 1 mm. The radial temperature profile is not significantly altered by longer irradiation times. CONCLUSIONS: The optimal dosimetry parameters for irradiation of human tonsillar tissue at 805 nm with the MILTA technique is under 15 watts for approximately 1 minute.