Irreversible Electroporation in Medicine

Abstract

This is a brief introduction to the emerging field of irreversible electroporation in medicine. Certain electrical fields when applied across a cell can have as a sole effect the permeabilization of the cell membrane, presumable through the formation of nanoscale defects in the cell membrane. Sometimes this process leads to cell death, primarily when the electrical fields cause permanent permeabilization of the membrane and the consequent loss of cell homeostasis, in a process known as irreversible electroporation. This is an unusual mode of cell death that is not understood yet. While the phenomenon of irreversible electroporation may have been known for centuries it has become only recently rigorously considered in medicine for various applications of tissue ablation. A brief historical perspective of irreversible electroporation is presented and recent studies in the field are discussed.

Magnetic induction of electroporation: Numerical analysis and technical limitations

“…The coil build with the calculated dimensions has an inductance close to 100 mH, as can be easily derived from (2). In order to drive a current of 5 kA at 4 MHz as proposed, a peak voltage of about 40 MV is needed.…”

“…The design goal is to perform reversible electroporation in the outer 2 mm layer: the epidermis and dermis [6]. In order to induce reversible electroporation we need to induce a minimum electric field of ⁄ [2].…”

“…During the application of an electrical pulse (approximately 400 mV [2]) across the cell membrane, charges accumulate due to migration of ions both inside and outside the cell medium. When a critical transmembrane voltage is reached, the lipids rapidly rearrange and their polar heads fold over, creating a hydrophilic interface between the inner and the outer medium.…”

“…This phenomenon is theoretically modeled as the formation of a conductive pore, which will allow the diffusion of hydrophilic macromolecules across the cell membrane. Finally, depending on the electrical pulse amplitude, exposure time, and critical defect size, the lipids may rearrange to its natural structure, resealing the lipid bilayer (reversible electroporation), or remain in the new structure, resulting in an irreversible electroporation (IRE) [2].…”

“…Since for IRE the cell membrane remains permeable, diffusion among the inner medium and the outer medium leads the cell to finally lose its homeostasis making it suitable for tissue ablation [2]. Conventional electroporators basically consist of two electrodes (separated a distance of few mm).…”