CO_2激光诱导生物组织光热效应的实验与理论研究

Theoretical and experimental research on photo-thermal effect of bio-tissues induced by CO_2 laser

结合温度实验和理论计算,进行了CO2激光与3种离体猪肉组织光热效应的比较研究。采用微型热电偶探针测量不同激光功率照射下组织的内部温度,采用二维有限元法(FEM)求解生物热传输方程,理论计算与实验条件相同。组织温度与激光照射时间和探针位置密切相关,根据所测温度曲线上升时间精确确定激光照射时间,根据实验和计算曲线的相似性确定探针轴向位置。结果显示,实验和理论计算的温度响应曲线形状基本一致,肝脏、肌肉和脂肪组织的峰值温度相对误差最小分别达到-0.69%、1.02%和-1.71%,温度曲线平均相对误差分别为1.67%、2.87%和5.77%,可在此基础上开展激光与组织光热效应的定量研究。

The photo-thermal effects of three kinds of porcine＇s in vitro tissues induced by COz laser compared and researched with temperature experiments and theoretical calculations. The miniature thermocouple probe is used to measure the tissue inner temperatures under different laser power irradiations. Theoretical calculations use the same experimental conditions and the two-dimensional finite element method to solve the bio-heat transfer equation. Tissue temperatures are closely related to the laser irradiation time and the probe location. The laser irradiation time is accurately determined according to the measured temperature curve rising time ,the probe axial positions were determined by the similarity between experimental and calculated curves. Results show that the experimental and theoretical temperature response curves are consistent. Liver,muscle and fat tissues＇ minimum peak temperature relative errors reach --0.69%,1.02% and --1.71%, and the temperature curve average relative errors are 1.87% ,2.87% and 5.77 % ,respectively. The quantitative research between laser and tissue photo-thermal effect can be conducted based on this method.