Introduction to Irreversible Electroporation--Principles and Techniques

Irreversible electroporation (IRE) is a novel nonthermal focal ablation technique that uses a series of brief but intense electric pulses delivered by paired electrodes into a targeted region of tissue, killing the cells by irreversibly disrupting cellular membrane integrity. Unlike other ablation methods, IRE has relatively little effect on connective tissues and nerves and has a low patient effect. The ability of IRE to achieve cell death immediately adjacent to large vessels without effect on the vessels themselves has raised the possibility of better treatment of advanced pancreatic cancer. Because of the low effect on the patient, IRE is well suited for use in conjunction with chemotherapeutic agents. The IRE effect is not uniform and is dependent on the intrinsic conductivity of the tissue, the number of pulses delivered, the current flow achieved, and the total time for the treatment. It is currently under investigation for a wide range of solid tumors and prostate cancer in humans and in animals in the breast, brain, and spinal cord. In clinical practice, IRE can be administered either percutaneously under imaging guidance or at open operation under direct vision. In animals there is some evidence of an immune response presumably due to exposure of the intracellular target material, resulting in a greater therapeutic effect. Unlike many other cancer treatments, IRE has been introduced for human clinical use at a very early stage of development of the technique and much of the basic understanding of how and when to use IRE is still under investigation.