基于射频消融治疗静脉曲张中温度对隐神经的热损伤仿真研究  

Simulation study of thermal injury to the saphenous nerve based on temperature in radiofrequency ablation for the treatment of varicose veins

作　　者：宋晓华 乔永琴 胡昊 南群[1,2] SONG Xiaohua;QIAO Yongqin;HU Hao;NAN Qun(College of Chemistry and Life Science,Beijing University of Technology,Beijing 100124;Beijing International Science and Technology Cooperation Base for Intelligent Physiological Measurement and Clinical Transformation,Beijing 100124;Peking University First Hospital,Beijing 100034)

机构地区：[1]北京工业大学化学与生命科学学院,北京100124 [2]智能化生理测量与临床转化北京市国际科研合作基地,北京100124 [3]北京大学第一医院,北京100034

出　　处：《北京生物医学工程》2024年第6期559-565,591,共8页Beijing Biomedical Engineering

基　　金：国家自然科学基金(31771021、11832003)资助。

摘　　要：目的 射频消融(radiofrequency ablation,RFA)治疗静脉曲张(varicose veins,VVs)术是通过在静脉腔内释放射频能量,以热效应损伤静脉内皮、从而闭合血管达到治疗目的。但由于隐神经与下肢静脉紧密伴行甚至缠绕,因此神经损伤是该术式最常见的并发症。为此,本文拟通过RFA治疗VVs的有限元计算和神经电生理建模相结合研究神经的损伤问题。方法 利用COMSOL多物理场软件建立静脉和神经三种不同相对位置的三维模型,采用电-热-流体耦合有限元方法计算组织周围的温度分布及神经的热损伤情况;利用MATLAB软件建立基于Hodgkin-Huxley神经电生理模型,进一步从神经元响应频率的角度验证温度升高对神经的影响。结果 血管周围的组织温度随着距离电极越远,温度逐渐降低。血管与神经伴行以及血管与神经相互缠绕的位置关系中,神经最高温度分别可达54.7℃、62.0℃。对于静脉位于两神经干之间的情况,在神经分叉处温度较高,可达到65.5℃。距离血管越近,温度分布越高。高于45℃后神经组织开始出现损伤,损伤区域以及损伤分数也随时间变化不断增大。神经在不同温度下受刺激产生动作电位时表现出不同的特性,在37~48℃之间,温度越高,神经元动作电位振动频率越高,振幅略有降低。温度超过48℃时神经元动作电位振动频率趋近于零。结论 神经位置的分布影响RFA治疗VVs的决策,RFA过程中的热量会对神经造成不可逆的损伤,48℃是治疗静脉曲张过程神经损伤的温度阈值。Objective Radiofrequency ablation(RFA) for the treatment of varicose veins(VVs) is a procedure in which radiofrequency energy is released into the vein lumen,damaging the endothelium of the vein with a thermal effect and closing the blood vessel to achieve the therapeutic goal.However,because the saphenous nerve is closely associated with or even entangled with the veins of the lower limbs,saphenous nerve injury is the most common complication of this procedure.Therefore,this paper intends to study the nerve damage by combining finite element calculations and neurophysiological modeling of RFA for VVs.Methods Three-dimensional models of veins and nerves at three different relative positions were established by using COMSOL multiphysics field software.The temperature distribution around the tissues and the thermal damage of the nerves were calculated by using the coupled electric-thermal-fluid finite element method.A Hodgkin-Huxley based neurophysiological model was developed with MATLAB software to further validate the effect of elevated temperature on nerves from the perspective of neuronal response frequency.Results The temperature of the tissue surrounding the blood vessels decreased progressively with distance from the electrodes.The maximum nerve temperatures in the positional relationships of vascular-nerve companion and vascular-nerve intertwining were up to 54.7 ℃ and 62 ℃,respectively.For cases where the vein was located between two nerve trunks,the temperature was higher at the bifurcation of the nerve and could reach 65.5 ℃.The temperature distribution increased with the proximity to blood vessels.Above 45 ℃ the nerve tissue began to show damage,and the area of damage as well as the fraction of damage increased with time.Nerves exhibited different properties when stimulated to generate action potentials at different temperatures.Between 37 ℃ and 48 ℃,the frequency of neuronal action potential vibration increased and the amplitude decreased slightly with increasing temperature.Neuronal actio

关 键 词：射频消融 静脉曲张 温度控制 Hodgkin-Huxley方程 神经元电生理 

分 类 号：R318[医药卫生—生物医学工程]