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The History of Bioelectromagnetism
Published in Shoogo Ueno, Tsukasa Shigemitsu, Bioelectromagnetism, 2022
Tsukasa Shigemitsu, Shoogo Ueno, Masamichi Kato
In 1974, Ulrich Zimmermann, professor at the University of Würzburg, Germany, concluded that membrane permeabilization occurs when the transmembrane potential reaches a threshold of 1 V (Zimmermann et al., 1974). The emphasis was that the result is relevant to irreversible electroporation parameters. The effects are not thermal. Zimmermann used reversible electroporation to produce fusion between cells after exposure to high electric field pulses (Zimmermann, 1982). In 1982, Neumann and his co-workers coined the term electroporation to describe the membrane breakdown induced by electric fields. They introduced first the use of reversible electroporation to insert genes into cells by pulsed electric fields (Neumann et al., 1982).
Microfluidic Electroporation and Applications
Published in Tuhin S. Santra, Microfluidics and Bio-MEMS, 2020
Koyel Dey, Srabani Kar, Pallavi Shinde, Loganathan Mohan, Saumendra Kumar Bajpai, Tuhin S. Santra
Chen et al. proposed a microwave-based biosensor that enables scrutinization of a single cell within its culture medium [83]. Later, by employing this device, Tamra et al. performed electroporation using microwave dielectric spectroscopy [110]. The microfluidic channel was placed on top of the coplanar waveguide circuit (Fig. 8.17b). The coplanar waveguide circuit consists of a capacitive gap at the center to trap a single cell. A mechanical trap was used to immobilize a single cell. After the cell was trapped, reversible SCEP was accomplished by using 8 pulses of 1 kV/cm with a pulse width of 100 μs and a frequency of 1 Hz with high cell viability (∼80%). For conducting irreversible electroporation the electric field was enhanced to 1.5 kV/cm.
Current Role of Focal Therapy for Prostate Cancer
Published in Ayman El-Baz, Gyan Pareek, Jasjit S. Suri, Prostate Cancer Imaging, 2018
H. Abraham Chiang, George E. Haleblian
The goal of this chapter is to review the technical aspects, oncologic outcomes, and functional outcomes with regard to various focal therapy modalities in the treatment of prostate cancer. The modalities reviewed include high-frequency focused ultrasound (HIFU), cryoablation, photodynamic therapy (PDT), laser interstitial thermotherapy (LITT), brachytherapy, irreversible electroporation (IRE), and radiofrequency ablation (RFA) (Table 6.1). Where applicable, the role of imaging guidance modalities will also be discussed. It is important to note that focal therapy for prostate cancer remains in various stages of clinical trials and is not currently standard of care for the management of prostate cancer.
Active esophageal cooling during radiofrequency ablation of the left atrium: data review and update
Published in Expert Review of Medical Devices, 2022
Julie Cooper, Christopher Joseph, Jason Zagrodzky, Christopher Woods, Mark Metzl, Robert W. Turer, Samuel A. McDonald, Erik Kulstad, James Daniels
Further research holds the potential to restore normal sinus rhythm more effectively and with greater safety than currently possible. Pulsed field energy to induce irreversible electroporation in cardiac tissue was first used in the 1980s but was superseded by radiofrequency ablation due to complications from early iterations of the technology (primarily barotrauma and microbubble formation). Newer approaches to utilizing pulsed field energy have recently been developed, with the anticipation that tissue selectivity might eliminate collateral damage during ablation of cardiac tissue. At present, there has been some progress in this area, with the caveat that demonstration of both safety and long-term efficacy has not been completed. A recent large survey of the first 1,758 cases treated with one of the first successfully commercialized systems for pulsed field ablation found significantly more complications than expected, prompting the authors to note that the high frequency of complications underscores the need for improvement.
Cryoablation as a first-line therapy for atrial fibrillation: current status and future prospects
Published in Expert Review of Medical Devices, 2022
Jason G. Andrade, Marc W. Deyell, Marc Dubuc, Laurent Macle
In addition, it is important to recognize the emerging role of pulsed field ablation. This non-thermal ablation energy modality affects tissue injury through the delivery of a sequence of high-amplitude, short-duration electrical pulses. Myocardial tissue is ablated through a mechanism known as irreversible electroporation, whereby exposure of tissue to a high-intensity electric field induces a charge across the lipid bilayer, resulting in the formation of cell membrane pores. This permeabilization allows to facilitate the entry of ions and macromolecules leading to apoptotic cellular death due to ATP-depletion and increased intracellular calcium concentration. Extremely high-intensity electric fields cause fragmentation of the phospholipid bilayer and cell necrosis. In contrast to radiofrequency and cryoenergy, lesion generation with pulsed field ablation is non-thermal, contact independent, and tissue selective (e.g. cells exposed to an electric field strength below the critical tissue-dependent electric field threshold will undergo reversible electroporation, whereby the pores close in time to reestablish homeostasis and regain viability). As such, it has been postulated that pulsed field ablation may offer an improved safety and efficacy profile relative to thermal ablation energies, positioning it as the preferred ablation energy for AF ablation procedures.
Technology of irreversible electroporation and review of its clinical data on liver cancers
Published in Expert Review of Medical Devices, 2018
Emil I. Cohen, David Field, George Emmett Lynskey, Alexander Y. Kim
Despite these gains, the percutaneous treatment of hepatic malignancies remains limited, especially for larger tumors or when the tumor lies in close proximity to a critical structure. The nonthermal nature of irreversible electroporation (IRE) allows ablation of tumors without significantly damaging adjacent structures. IRE has demonstrated promise in the treatment of pancreatic adenocarcinoma, the treatment of which often is complicated by the proximity of crucial structures. Similarly, IRE may be useful for the safe ablation of centrally located liver tumors, which often are in close apposition to vital structures. Despite several series demonstrating its safety and efficacy [2–11], however, IRE remains underutilized in the treatment of both primary and secondary liver cancers.