Thermal tissue injury is an unintended consequence in current irreversible electroporation treatments due to the induction of Joule heating during the delivery of high voltage pulsed electric fields. In this study active temperature control measures including internal electrode cooling and dynamic energy delivery were investigated as a process for mitigating thermal injury during treatment. Ex vivo liver was used to examine the extent of thermal injury induced by 5000 V treatments with delivery rates up to five times faster than current clinical practice. Active internal cooling of the electrode resulted in a 36% decrease in peak temperature vs. non-cooled control treatments. A temperature based feedback algorithm (electro-thermal therapy) was demonstrated as capable of maintaining steady state tissue temperatures between 30 and 80 °C with and without internal electrode cooling. Thermal injury volumes of 2.6 cm3 were observed for protocols with 60 °C temperature set points and electrode cooling. This volume reduced to 1.5 and 0.1 cm3 for equivalent treatments with 50 °C and 40 °C set points. Finally, it was demonstrated that the addition of internal electrode cooling and active temperature control algorithms reduced ETT treatment times by 84% (from 343 to 54 s) vs. non-cooled temperature control strategies with equivalent thermal injury volumes.

中文翻译：

---

电热疗法算法和主动内部电极冷却可减少高频脉冲电场癌症疗法中的热损伤。

热组织损伤是当前不可逆电穿孔治疗中的意外后果，这是由于在输送高压脉冲电场期间会产生焦耳热。在这项研究中，包括内部电极冷却和动态能量传递在内的主动温度控制措施被研究作为减轻治疗过程中热损伤的过程。离体肝脏用于检查由 5000 V 治疗引起的热损伤程度，其递送速率比当前临床实践快五倍。与非冷却对照处理相比，电极的主动内部冷却导致峰值温度降低了 36%。基于温度的反馈算法（电热疗法）被证明能够在有和没有内部电极冷却的情况下将稳态组织温度维持在 30 到 80 °C 之间。对于具有 60 °C 温度设定点和电极冷却的协议，观察到 2.6 cm3 的热损伤体积。对于具有 50 °C 和 40 °C 设定点的等效处理，该体积减少到 1.5 和 0.1 cm3。最后，结果表明，与具有等效热损伤体积的非冷却温度控制策略相比，添加内部电极冷却和主动温度控制算法将 ETT 治疗时间减少了 84%（从 343 秒到 54 秒）。5 和 0.1 cm3 对于具有 50 °C 和 40 °C 设定点的等效处理。最后，结果表明，与具有等效热损伤体积的非冷却温度控制策略相比，添加内部电极冷却和主动温度控制算法将 ETT 治疗时间减少了 84%（从 343 秒到 54 秒）。5 和 0.1 cm3 对于具有 50 °C 和 40 °C 设定点的等效处理。最后，结果表明，与具有等效热损伤体积的非冷却温度控制策略相比，添加内部电极冷却和主动温度控制算法将 ETT 治疗时间减少了 84%（从 343 秒到 54 秒）。