激光辐照生物组织傅里叶与非傅里叶热传导效应

Fourier and Non-Fourier Heat Conduction Effects in Biological Tissue under Laser Irradiation

对描述激光辐照生物组织光热响应的经典生物热传递模型和生物热波模型进行比较,分析两种模型的适用条件及影响因素。结果表明,当激光辐照时间接近或小于生物组织热释放时间时,基于生物热波模型的结果与经典生物热传导模型的结果差异明显,采用后者对热损伤进行评估引起的误差较大。对于生物热波模型,考察点所在深度越浅,非傅里叶导热特征越明显。比较两种生物热传导模型,第一层血液灌注率和吸收系数对辐射原点的瞬态温度分布均有影响,但不改变其热特征。

This letter compared the classical Pennes bioheat transfer model and the thermal wave model of bioheat transfer,which have often been used to describe the photothermal response on laser-tissue interaction. The conditions and influence factors of these two models were analyzed. The results show that when the laser-irradiated duration time is comparable to or shorter than the thermal release time in biological tissue,the results obtained by the thermal wave model and the classical Pennes bioheat transfer model are obviously different. The thermal damage assessment based on the latter model may cause more error. For the thermal wave model,the non-Fourier effect is more obvious in shallow area. The effects of blood perfusion rate and absorption coefficient of the first layer tissue on transient temperature and its characteristic at the irradiated origin were investigated.