Publications by authors named "P Agnass"

Introduction: Irreversible electroporation (IRE) is an ablation modality that applies short, high-voltage electric pulses to unresectable cancers. Although considered a non-thermal technique, temperatures do increase during IRE. This temperature rise sensitizes tumor cells for electroporation as well as inducing partial direct thermal ablation.

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This paper presents three devices suitable for the preclinical application of hyperthermia via the simultaneous high-resolution imaging of intratumoral events. (Pre)clinical studies have confirmed that the tumor micro-environment is sensitive to the application of local mild hyperthermia. Therefore, heating is a promising adjuvant to aid the efficacy of radiotherapy or chemotherapy.

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Electric permeabilization of cell membranes is the main mechanism of irreversible electroporation (IRE), an ablation technique for treatment of unresectable cancers, but the pulses also induce a significant temperature increase in the treated volume. To investigate the therapeutically thermal contribution, a preclinical setup is required to apply IRE at desired temperatures while maintaining stable temperatures. This study's aim was to develop and test an electroporation device capable of maintaining a pre-specified stable and spatially homogeneous temperatures and electric field in a tumor cell suspension for several clinical-IRE-settings.

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Aims: First, the aim of the study was to determine whether irreversible electroporation (IRE) is associated with heat generation in the liver and pancreas at clinical (≤1,500 V/cm) and supraclinical (>1,500 V/cm) electroporation settings; second, to assess the risk of thermal tissue damage in and adjacent to the treated volume in highly perfused versus moderately perfused parts of both organs; third, to investigate the influence of perfusion and of the presence and the orientation of a metal stent on the maximal thermal elevation (ΔT) in the tissue during an IRE session at fixed IRE settings, and finally, to determine whether the maximum temperature elevation within the IRE-subjected organ during an IRE treatment (single or multiple sessions) is reflected in the organ's surface temperature.

Methods: The aims were investigated in 12 case studies conducted in five female Landrace pigs. Several IRE settings were applied for lateral (2), triangular (3), and rectangular (4) electrode configurations in the liver hilum, liver periphery, pancreas head, and pancreas tail.

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Irreversible electroporation (IRE) is a relatively new ablation method for the treatment of unresectable cancers. Although the main mechanism of IRE is electric permeabilization of cell membranes, the question is to what extent thermal effects of IRE contribute to tissue ablation. This systematic review reviews the mathematical models used to numerically simulate the heat-generating effects of IRE, and uses the obtained data to assess the degree of mild-hyperthermic (temperatures between 40 °C and 50 °C) and thermally ablative (TA) effects (temperatures exceeding 50 °C) caused by IRE within the IRE-treated region (IRE-TR).

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