Study on temperature of liver and tumor under high frequency nanosecond pulsed field

Electroporation has many advantages in the tumor treatment. However, the presence of muscle tonic contraction had been found during pulsed electric field processing and clinically been verified. Therefore, researchers introduce the use of high-frequency nanosecond pulsed electric fields (nsPEF) for tissue electroporation, which can inhibit or eliminate muscle contraction. As biological tissues are conductive, an electrical current is flowing when pulse is delivered and resistive heating is also taking place. Because of the high field intensity of nanosecond pulse, it is necessary to study on the thermal effects among normal and abnormal tissues. This analysis is based on finite-element model of liver with tumor in which a pair of needle electrodes was applied. The pulse voltage is from 1kVto 4kV, the pulse width is ranging from 50ns to 500ns and the frequency is between 100k and 1MHz. Blood flows and metabolic heat generation are also been considered. Results show that different contributions to temperature of tissue when applied different parameters of pulses. By the simulation, we can get the upper limit of pulse parameters for high frequency nsPEF not causing large temperature rise.