通过有限元建模模拟的跨 MEP 值电压和电流密度
Lanjun Guo1, Enock Boakye2, Rosalind J Sadleir2
1Department of Surgical Neurophysiology, University of California - San Francisco, San Francisco, CA, USA.
概括
链接四极 (LQP) 组装需要对跨肌运动唤起潜能 (tcMEPs) 的最低刺激值. 有限元模型显示,皮层几何学主要影响电流分布,而不是电极组装.
科学领域:
- 神经科学是一个神经科学.
- 生物医学工程 生物医学工程
- 神经外科 神经外科
背景情况:
- 在神经外科手术期间监测运动通路时,跨骨运动唤起潜能 (tcMEPs) 是至关重要的.
- 优化tcMEP刺激需要了解电极安装对电流输送和值的影响.
研究的目的:
- 为了比较tcMEP的刺激值和脑电流密度,使用连接四极 (LQP),M3-M4和C1-C2电极组装.
- 研究电极安装对运动皮层电流分布的影响.
主要方法:
- 研究了25名接受脑血管外科手术的患者,并进行了tcMEP监测.
- 在LQP,M3-M4和C1-C2组装中比较了tcMEP电压值.
- 有限元模型 (FEM) 在tcMEP值时模拟了手,手臂和腿部感兴趣区域 (ROI) 的电流密度.
主要成果:
- 对于手 (61.5V) 和脚 (95.2V) 刺激,LQP组装显示了最低的tcMEP电压值.
- M3-M4和C1-C2组装需要显著更高的门.
- FEM模拟表明,皮质几何形状,而不是电极安装,主要决定了运动皮质的局部电流密度分布.
结论:
- 对于tcMEP刺激,LQP组装是最有效的,需要更低的电压值.
- FEM模拟表明,在特定的皮质区域内固有的电流阻力,受几何学影响,在不同组装中确定tcMEP值方面发挥着关键作用.
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