植入式肿瘤电场治疗胶质母细胞瘤的建模与仿真研究

Modeling and simulation study of implantable tumor electric field for glioblastoma

目的 研究植入式肿瘤电场治疗胶质母细胞瘤的可行性。方法 通过COMSOL有限元仿真,探索相位差、触点设置、电极数量和电压等参数对电场的分布的影响,逐步优化参数,探索电场覆盖范围的影响因素。结果 合理地设置相位差在相同电压下可以扩大电场覆盖的范围,并提出了一种双层环绕递增相差设置方法。以5根电极5 V电压为例,对比了不同数量的触点激活的电场分布范围,阐明了双层触点激活的优势及触点选择的方式。仿真了使1 V/cm的有效治疗电场覆盖不同大小残腔切除边缘所需的最少电极数量和最小整数电压,3根电极6 V的电压即可覆盖直径2 cm残腔的切除边缘,而直径5 cm的残腔需要5根电极和10 V的电压。针对直径3.5 cm的残腔探究了电极数量与电压的相互替代关系。结论 脑肿瘤切除术后通过植入式电极可以将中频交变电场聚焦在切除边缘附近,优化参数可以覆盖残腔表面,场强超过1 V/cm,表明植入式肿瘤电场治疗是一种潜在可行的治疗方案。该治疗方案的安全性、器械小型化和供能则仍需进一步的研究。

Objective To discuss the feasibility of implantable tumor treating fields for glioblastoma.Methods A set of finite element method electric field computer simulations were conducted using COMSOL,exploring the influence of parameters such as phase shift,contact setting,electrode quantities and voltage on the distribution of electric field.The influencing factors of the coverage range of electric field on resection cavity boundaries was revealed through optimizing the parameters step by step.Results Adequate setting of phase difference can increase the coverage range under the same voltage,and a double-layer surrounded incremental phase difference setting method was proposed.Taking 5 electrodes with 5 V voltage as an example,different numbers of contact activations were compared to elucidating the advantages of double-layer contact activation and the way of contact selection.The minimum number of electrodes required to make an effective therapeutic electric field of 1 V/cm to cover different sizes of resection cavities and the minimum integer voltage were simulated.3 electrodes with 6 V could cover the boundary of a 2 cm diameter resection cavity,whereas 5 electrodes and a voltage of 10 V were required for resection cavities with a diameter of 5 cm.The reciprocal substitution of the number of electrodes and voltage was explored for a 3.5 cm diameter resection cavity.Conclusions A mid-frequency alternating electric field can be focused near the resection margin by implantable electrodes after brain tumor resection.Optimization of parameters can extend coverage to the resection cavity surface,with field strengths exceeding 1 V/cm,indicating that implantable tumor electric field therapy is a potentially viable treatment option.However,further research is required to assess the safety and miniaturization of the instrumentation,as well as the power supply aspects of this therapeutic approach.