Abstract

Introduction: Irreversible electroporation (IRE) is a relatively new ablation method for the treatment of unresectable cancers. Although the main mechanism of IRE is electric permeabilization of cell membranes, the question is to what extent thermal effects of IRE contribute to tissue ablation.

Aim: This systematic review reviews the mathematical models used to numerically simulate the heat-generating effects of IRE, and uses the obtained data to assess the degree of mild-hyperthermic (temperatures between 40 °C and 50 °C) and thermally ablative (TA) effects (temperatures exceeding 50 °C) caused by IRE within the IRE-treated region (IRE-TR).

Methods: A systematic search was performed in medical and technical databases for original studies reporting on numerical simulations of IRE. Data on used equations, study design, tissue models, maximum temperature increase, and surface areas of IRE-TR, mild-hyperthermic, and ablative temperatures were extracted.

Results: Several identified models, including Laplace equation for calculation of electric field distribution, Pennes Bioheat Equation for heat transfer, and Arrhenius model for thermal damage, were applied on various electrode and tissue models. Median duration of combined mild-hyperthermic and TA effects is 20% of the treatment time. Based on the included studies, mild-hyperthermic temperatures occurred in 30% and temperatures ≥50 °C in 5% of the IRE-TR.

Conclusions: Simulation results in this review show that significant mild-hyperthermic effects occur in a large part of the IRE-TR, and direct thermal ablation in comparatively small regions. Future studies should aim to optimize clinical IRE protocols, maintaining a maximum irreversible permeabilized region with minimal TA effects.

摘要

简介：不可逆电穿孔（IRE）是治疗无法切除的癌症的一种相对较新的消融方法。尽管IRE的主要机制是细胞膜的电渗透，但问题是IRE的热效应在多大程度上有助于组织消融。

目的：本系统综述回顾了用于对IRE的热生成进行数值模拟的数学模型，并使用获得的数据评估了轻度高温（温度在40°C至50°C之间）和热剥蚀性（TA）的程度。 ）在IRE处理区域（IRE-TR）内由IRE引起的影响（温度超过50°C）。

方法：在医学和技术数据库中进行系统搜索，搜索关于IRE数值模拟的原始研究。提取有关使用的方程式，研究设计，组织模型，最大温度升高以及IRE-TR的表面积，温和的高温和烧蚀温度的数据。

结果：在各种电极和组织模型上应用了几种已确定的模型，包括用于计算电场分布的Laplace方程，用于传热的Pennes Bioheat方程和用于热损伤的Arrhenius模型。亚低温和TA联合作用的中位持续时间为治疗时间的20％。根据纳入的研究，在IRE-TR的5％中发生了30％的温度过高的温度，而在5％的IRE-TR中发生了≥50°C的温度。

结论：本次审查的模拟结果表明，IRE-TR的大部分出现了明显的轻度高热效应，并且在相对较小的区域中进行了直接热消融。未来的研究应旨在优化临床IRE方案，以最小的TA效应维持最大的不可逆通透区。