Department of Biomedical Engineering and Mechanics, Virginia Tech-Wake Forest University, Blacksburg, VA, USA.
Department of Biomedical Engineering and Mechanics, Virginia Tech-Wake Forest University, Blacksburg, VA, USA.
Comput Biol Med. 2023 Jul;161:107019. doi: 10.1016/j.compbiomed.2023.107019. Epub 2023 May 16.
The nonthermal mechanism for irreversible electroporation has been paramount for treating tumors and cardiac tissue in anatomically sensitive areas, where there is concern about damage to nearby bowels, ducts, blood vessels, or nerves. However, Joule heating still occurs as a secondary effect of applying current through a resistive tissue and must be minimized to maintain the benefits of electroporation at high voltages. Numerous thermal mitigation protocols have been proposed to minimize temperature rise, but intraoperative temperature monitoring is still needed. We show that an accurate and robust temperature prediction AI model can be developed using estimated tissue properties (bulk and dynamic conductivity), known geometric properties (probe spacing), and easily measurable treatment parameters (applied voltage, current, and pulse number). We develop the 2-layer neural network on realistic 2D finite element model simulations with conditions encompassing most electroporation applications. Calculating feature contributions, we found that temperature prediction is mostly dependent on current and pulse number and show that the model remains accurate when incorrect tissue properties are intentionally used as input parameters. Lastly, we show that the model can predict temperature rise within ex vivo perfused porcine livers, with error <0.5 °C. This model, using easily acquired parameters, is shown to predict temperature rise in over 1000 unique test conditions with <1 °C error and no observable outliers. We believe the use of simple, readily available input parameters would allow this model to be incorporated in many already available electroporation systems for real-time temperature estimations.
不可逆电穿孔的非热机制对于治疗肿瘤和解剖学上敏感区域的心脏组织至关重要,因为人们担心电流通过电阻组织时会对附近的肠道、管道、血管或神经造成损伤。然而,焦耳加热仍然是通过电阻组织施加电流的次要效应,必须最小化,以保持高电压下电穿孔的益处。已经提出了许多热缓解协议来最大限度地降低温度升高,但仍需要进行术中温度监测。我们表明,可以使用估计的组织特性(体和动态电导率)、已知的几何特性(探头间距)以及易于测量的治疗参数(施加的电压、电流和脉冲数)来开发准确且稳健的温度预测 AI 模型。我们在具有涵盖大多数电穿孔应用条件的二维有限元模型模拟上开发了两层神经网络。通过计算特征贡献,我们发现温度预测主要取决于电流和脉冲数,并且当故意将不正确的组织特性用作输入参数时,该模型仍然准确。最后,我们表明该模型可以预测离体灌注猪肝中的温升,误差<0.5°C。该模型使用易于获取的参数,在超过 1000 种独特的测试条件下进行预测,误差<1°C,且没有观察到异常值。我们相信,使用简单、易于获得的输入参数可以使该模型集成到许多现有的电穿孔系统中,以进行实时温度估计。