基于真实解剖模型的肺肿瘤微波消融研究

Study on microwave ablation of lung tumor based on real anatomical model

目的:基于真实解剖模型研究肺肿瘤的微波消融(microwave ablation,MWA)结果,以更有效地规划微波天线的穿刺方向,实现个性化术前仿真。方法:首先,基于真实患者的肺部CT数据构建由肺组织、肿瘤和血管系统等组成的个性化MWA仿真模型。其次,通过对电磁场和生物传热场2个物理场进行耦合求解来仿真MWA效果,得到消融热凝固区的大小和肺组织的温度分布。最后,从电导率和血液灌注2个维度定量评估血管网络对消融结果的影响,并分析大血管与天线处于不同距离(大血管与天线尖端相距5和10 mm)和穿刺方向下(大血管相对于天线尖端平行和相交)的消融结果。结果:血管网络的存在使热凝固区体积减小0.5%~3.7%,且血液灌注使得消融温度大幅下降、热凝固区体积大幅减小。随着大血管与天线之间的距离增加,大血管所带来的降温效果逐渐减小。在相同的治疗参数下,大血管与天线处于平行方向形成的热凝固区明显大于相交方向形成的热凝固区。结论:基于真实CT数据的个性化MWA仿真分析可获得更接近实际情况的温度分布和损伤估算,从而为MWA精准治疗肺肿瘤以及协助医生确定微波天线的穿刺方向提供重要的参考和指导。

Objective To plan microwave antenna puncture direction effectively and realize personalized preoperative simulation by exploring microwave ablation(MWV)outcomes of lung cancer based on real anatomical model.Methods Firstly,a personalized MWA simulation model consisting of the lung tissue,tumor and vascular system was constructed based on the lung CT data of real patients.Secondly,the MWA effect was simulated by coupling 2 physical fields including an electromagnetic field and a biological heat transfer field,so as to determine the volume of the ablation thermocoagulation zone and the temperature distribution of the lung tissue.Finally,the effects of the vascularized network on the ablation results were quantitatively evaluated in terms of conductivity and blood perfusion,and the ablation results were analyzed with different distances between the large vessels and the antennae(5 and 10 mm from the antennae tips)and puncture angles(large vessels parallelling or intersecting with the antennae tips).Results The vascularized network reduced the volume of the thermocoagulation zone by 0.5%to 3.7%,and blood perfusion made the ablation temperature and the volume of the thermocoagulation zone decreased significantly.The cooling effect gradually diminished with the increase of the distance between the large vessels and the antenna.With the same treatment parameters,the thermocoagulation zone formed when the large vessels paralleled with the antenna was obviously larger than that when the vessles intersected with the antenna.Conclusion Personalized MWA simulation analysis based on real CT data contributes to clarifying the temperature distribution and damage estimation close to the actual situation,which provides guidance and reference for precise treatment of the lung tumor and determination of microwave antenna puncture direction.[Chinese Medical Equipment Journal,2024,45(9):27-34]