Analysis of thermal relaxation during laser irradiation of tissue

Thermal relaxation time (τr) is a commonly‐used parameter for estimating the time required for heat to conduct away from a directly‐heated tissue region. Previous studies have demonstrated that temperature superposition can occur during multiple‐pulse irradiation, even if the interpulse time is considerably longer than τr. The objectives of this study were (1) to analyze tissue thermal relaxation following laser‐induced heating, and (2) to calculate the time required for a laser‐induced temperature rise to decrease to near‐baseline values.

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