Tissue ablation by irreversible electroporation

Abstract

The phenomenon of electroporation can be traced back to the eighteenth century when red spots on skin (Lichtenberg figures) were observed in the areas where electric fields were applied. Once the cause of this occurrence was understood and controlled, induction of electric fields was achieved; the use of pulsed electric fields was adopted in the areas of food and water sterilization to kill microbial organisms. Applications in biomedicine soon followed where electric fields began to play a role in the transport of and into biological material employing a technique known as reversible electroporation in which temporary cell membrane destabilization is achieved followed by complete recovery of membrane integrity. Irreversible electroporation (IRE) induces cell death presumably through a loss of homeostasis by using an energy regime substantially higher than that of reversible electroporation. When pulse parameters are carefully designed, IRE can be used to ablate large volumes of tissue in such a manner that it does not induce significant traditional thermal damage. This application of IRE for the treatment of disease has been widely investigated through in vitro studies, in vivo animal studies, and treating human patients through clinical trials. Its nonthermal mechanism to induce cell death makes it an attractive modality to safely treat unresectable tumors. When careful treatment planning is performed to account for tumor morphology, tissue heterogeneity, and parameters for pulse delivery, it has been shown to successfully treat cancerous tumors safely. Clinical use of IRE includes the treatment of liver, lung, pancreas, and prostate cancer among others. IRE has found tremendous promise for the treatment of pancreatic and prostatetumors. Further research and optimization of this technique point to an accelerated adoption for its clinical use to treat various types of cancer and other debilitating conditions.