Neal Robert E, Garcia Paulo A, Robertson John L, Davalos Rafael V
Bioelectromechanical Systems Laboratory, Virginia Tech-Wake Forest School of Biomedical Engineering and Sciences, Virginia Tech, Blacksburg, VA 24060, USA.
Annu Int Conf IEEE Eng Med Biol Soc. 2011;2011:5581-4. doi: 10.1109/IEMBS.2011.6091350.
Cells exposed to short electric pulses experience a change in their transmembrane potential, which can lead to increased membrane permeability of the cell. When the energy of the pulses surpasses a threshold, the cell dies in a non-thermal manner known as irreversible electroporation (IRE). IRE has shown promise in the focal ablation of pathologic tissues. Its non-thermal mechanism spares sensitive structures and facilitates rapid lesion resolution. IRE effects depend on the electric field distribution, which can be predicted with numerical modeling. When the cells become permeabilized, the bulk tissue properties change, affecting this distribution. For IRE to become a reliable and successful treatment of diseased tissues, robust predictive treatment planning methods must be developed. It is vital to understand the changes in tissue properties undergoing the electric pulses to improve numerical models and predict treatment volumes. We report on the experimental characterization of these changes for kidney tissue. Tissue samples were pulsed between plate electrodes while intrapulse voltage and current data were measured to determine the conductivity of the tissue during the pulse. Conductivity was then established as a function of the electric field to which the tissue is exposed. This conductivity curve was used in a numerical model to demonstrate the impact of accounting for these changes when modeling electric field distributions to develop treatment plans.
暴露于短电脉冲的细胞会经历跨膜电位的变化，这可能导致细胞的膜通透性增加。当脉冲能量超过阈值时，细胞会以一种称为不可逆电穿孔（IRE）的非热方式死亡。IRE在病理性组织的局部消融中显示出前景。其非热机制可使敏感结构免受损伤，并有助于快速消除病变。IRE效应取决于电场分布，这可以通过数值建模来预测。当细胞通透性增加时，大块组织的特性会发生变化，从而影响这种分布。为了使IRE成为一种可靠且成功的疾病组织治疗方法，必须开发强大的预测性治疗计划方法。了解经历电脉冲的组织特性变化对于改进数值模型和预测治疗体积至关重要。我们报告了肾脏组织这些变化的实验特征。在平板电极之间对组织样本施加脉冲，同时测量脉冲内的电压和电流数据，以确定脉冲期间组织的电导率。然后将电导率确定为组织所暴露电场的函数。该电导率曲线用于数值模型，以证明在为制定治疗计划而对电场分布进行建模时考虑这些变化的影响。
