中文摘要：

为了综合传统不可逆电穿孔和ns脉冲的特点，充分发挥脉冲电场非热治疗肿瘤的优势，将高频ns脉冲串引入到消融肿瘤组织的应用中，并研究了此高频ns脉冲串在生物组织中产生的热效应。通过多参数有限元方法对施加1对针电极的肝脏和肿瘤组织的温度以及热损伤进行了仿真，施加的电压范围为1-4kV，脉冲宽度范围为50-500ns，重复频率介于100kHZ-1MHz之间，脉冲串长度为100μs，脉冲串的重复频率为1Hz。使用Pennes生物传热方程计算电热耦合下的温度，并根据Arrhenius公式计算热损伤。结果表明：肿瘤在单个脉冲串作用下在100μs时刻达到的最高温度为49．26℃；在1s时刻最高温度为40．4℃，经过1s时刻之后热损伤的累积程度只有0．0016，不会造成热损伤：通过参数拟合，可以得到任意参数下的组织温度以及热损伤。研究结果可为将来的实验研究提供参数选择的理论依据。

英文摘要：

In order to combine characteristics of traditional irreversible electroporation and nanosesond pulses, and to take full advantages of non thermal treatment of pulsed electric fields, the high-frequency nanosecond pulsed bursts was in- troduced for tumor ablation, and the thermal effects of it were studied. The temperature and thermal damage of the liver and tumor tissue, which have been punctured one pair of needle electrodes, were simulated by the multi-parameter finite element method. The pulse voltage used in this study ranges from 1 to 4 kV, the pulse width ranges from 50 to 500 ns, and the repetition frequency is between 100 kHz and 1 MHz. The total pulse length is 100 μs, and the pulse burst repetition frequency is 1 Hz. The temperature under the thermocouple coupling was calculated using the Permes biological heat transfer equation, and the thermal damage was calculate according to the Arrhenius formula. The research results indicated that the maximum temperature of the tumor reached at 100 μs was 49.26℃ under the single pulse train; the maximum temperature was 40.4℃ at 1 s, and the cumulative degree of thermal damage after 1 s was only 0.001 6, it will not cause thermal damage. By parameter fitting, the maximum and final temperatures under any parameter combinations can be obtained. These results can provide theoretical basis of pulse parameter selection for future experimental researches.