IEEE Trans Biomed Eng. 2022 Jan;69(1):302-313. doi: 10.1109/TBME.2021.3092889. Epub 2021 Dec 23.
In cancer treatment, laser ablation is a promising technique used to induce localized thermal damage. Different variables influence the temperature distribution in the tissue and the resulting therapy efficacy; thus, the optimal therapy settings are required for obtaining the desired clinical outcome. In this work, thermomechanical modeling of contactless laser ablation was implemented to analyze the sensitivity of independent variables on the optimal treatment conditions. The Finite Element Method was utilized to solve the governing equations, i.e., the bioheat, mechanical deformation, and the Navier-Stokes equations. Validation of the model was performed by comparing experimental and simulated temperatures, which indicated high accuracy for estimating temperature. In particular, the results showed that the model can estimate temperature with a good correlation factor (R = 0.98) and low Mean Absolute Error (3.9 °C). A sensitivity analysis based on laser irradiation time, power, beam distribution, and the blood vessel depth on temperature distribution and fraction of necrotic tissue was performed. An optimization process was performed based on the most significant variables, i.e., laser irradiation time and power. This resulted in an indication of the optimal therapy settings for achieving maximum procedure efficiency i.e., the required fraction of necrotic tissue within the target volume, constituted by tumor and safety margins around it.
在癌症治疗中，激光烧蚀是一种有前途的技术，用于诱导局部热损伤。不同的变量会影响组织中的温度分布和治疗效果；因此，需要优化治疗参数以获得理想的临床结果。在这项工作中，采用热机械模型对非接触式激光烧蚀进行了模拟，以分析独立变量对最佳治疗条件的敏感性。利用有限元法求解控制方程，即生物传热、力学变形和纳维-斯托克斯方程。通过比较实验和模拟温度来验证模型的准确性，结果表明模型能够以良好的相关系数（R=0.98）和较低的平均绝对误差（3.9°C）来估计温度。基于激光照射时间、功率、光束分布以及血管深度对温度分布和坏死组织比例的影响，进行了敏感性分析。基于最显著的变量（即激光照射时间和功率）进行了优化处理。这为实现最大程序效率即目标体积内所需的坏死组织比例（由肿瘤及其周围安全边界组成）提供了最佳治疗参数的指示。
