【摘要】 建立了光动力疗法(PDT)照射方式下578nm激光视网膜热损伤能量密度阈值计算的数值模型。模型由模拟激光能量在组织内分布规律的基于网格的Monte Carlo模拟方法、计算组织内温度分布的考虑组织热物性参数以及血液灌注率动态变化的Penens生物传热方程和计算组织热损伤程度的Arrhenius方程3部分组成。数值结果表明,视网膜热损伤能量密度阈值随黑色素含量、观测时间和光斑大小不同而不同:黑色素含量越高,热损伤能量密度阈值越小;观测时间越长,热损伤能量密度阈值越大;光斑直径越大,热损伤能量密度阈值越小。活体动物实验验证了数值结果的精确性。更多还原

【Abstract】 A numerical model of threshold energy density for retinal thermal damage(Dth) from 578 nm laser under the photodynamic therapy(PDT) exposing way was developed which uses the element-based Monte Carlo method to simulate the laser transport in the tissue,the Pennes bioheat transfer equation with variable thermal properties and variable blood perfusion rate to calculate the temperature distribution,and the Arrhenius equation to predict the thermal damage.The numerical results show that Dth decreases when melanin volumetric fraction and diameter of laser beam increase,while Dth increases when scheduled time increases.The accuracy of the numerical results is verified by animal experiments.更多还原