Electrical breakdown in tissue electroporation.
Electroporation, the permeabilization of the cell membrane by brief, high electric fields, has become an important technology in medicine for diverse application ranging from gene transfection to tissue ablation. There is ample anecdotal evidence that the clinical application of electroporation is often associated with loud sounds and extremely high currents that exceed the devices design limit after which the devices cease to function. The goal of this paper is to elucidate and quantify the biophysical and biochemical basis for this phenomenon. Using an experimental design that includes clinical data, a tissue phantom, sound, optical, ultrasound and MRI measurements, we show that the phenomenon is caused by electrical breakdown across ionized electrolysis produced gases near the electrodes. The breakdown occurs primarily near the cathode. Electrical breakdown during electroporation is a biophysical phenomenon of substantial importance to the outcome of clinical applications. It was ignored, until now.
Inter Science, Reusblickstr 23, 6038 Gisikon, Luzern, Switzerland; Institut fuer Bildgebende Diagnostik, Strahlenbergerstrasse 110, 63067 Offenbach, Germany.
Enric
E
Guenther
Inter Science, Reusblickstr 23, 6038 Gisikon, Luzern, Switzerland; Institut fuer Bildgebende Diagnostik, Strahlenbergerstrasse 110, 63067 Offenbach, Germany. Electronic address: klein@bilddiagnostik.de.
Nina
N
Klein
Inter Science, Reusblickstr 23, 6038 Gisikon, Luzern, Switzerland.
Paul
P
Mikus
Inter Science, Reusblickstr 23, 6038 Gisikon, Luzern, Switzerland; Institut fuer Bildgebende Diagnostik, Strahlenbergerstrasse 110, 63067 Offenbach, Germany.
Michael K
MK
Stehling
Inter Science, Reusblickstr 23, 6038 Gisikon, Luzern, Switzerland; Department of Mechanical Engineering, University of California Berkeley, Berkeley, CA 94720, USA.
Boris
B
Rubinsky
D055011:Ablation Techniques / Q000379:methods; D000162:Acoustics / Q000295:instrumentation; D017097:Electric Impedance; D004566:Electrodes; D055724:Electrophysiological Phenomena; D018274:Electroporation / Q000295:instrumentation / Q000379:methods*; D006801:Humans; D008279:Magnetic Resonance Imaging; D008297:Male; D019047:Phantoms, Imaging; D011467:Prostate / Q000000981:diagnostic imaging / Q000502:physiology; D011471:Prostatic Neoplasms / Q000000981:diagnostic imaging / Q000601:surgery / Q000628:therapy*; D014463:Ultrasonography
Electrolysis; Electrolytic electroporation; Irreversible electroporation; Magnetic resonance imaging; NanoKnife; Tissue ablation