Avoiding neuromuscular stimulation in liver irreversible electroporation using radiofrequency electric fields

Phys Med Biol. 2018 Jan 31;63(3):035027. doi: 10.1088/1361-6560/aaa16f.


Electroporation-based treatments typically consist of the application of high-voltage dc pulses. As an undesired side effect, these dc pulses cause electrical stimulation of excitable tissues such as motor nerves. The present in vivo study explores the use of bursts of sinusoidal voltage in a frequency range from 50 kHz to 2 MHz, to induce irreversible electroporation (IRE) whilst avoiding neuromuscular stimulation. A series of 100 dc pulses or sinusoidal bursts, both with an individual duration of 100 µs, were delivered to rabbit liver through thin needles in a monopolar electrode configuration, and thoracic movements were recorded with an accelerometer. Tissue samples were harvested three hours after treatment and later post-processed to determine the dimensions of the IRE lesions. Thermal damage due to Joule heating was ruled out via computer simulations. Sinusoidal bursts with a frequency equal to or above 100 kHz did not cause thoracic movements and induced lesions equivalent to those obtained with conventional dc pulses when the applied voltage amplitude was sufficiently high. IRE efficacy dropped with increasing frequency. For 100 kHz bursts, it was estimated that the electric field threshold for IRE is about 1.4 kV cm-1 whereas that of dc pulses is about 0.5 kV cm-1.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Electric Stimulation / adverse effects*
  • Electroporation / methods*
  • Liver / pathology
  • Liver / radiation effects*
  • Models, Theoretical
  • Muscles / pathology
  • Muscles / radiation effects*
  • Nerve Fibers / pathology
  • Nerve Fibers / radiation effects*
  • Organs at Risk / radiation effects*
  • Rabbits