大脑的移动和压力是由于表面压力差异引起的吗? 一个计算建模研究研究
Eleonora Piersanti1,2, Marie E Rognes1, Vegard Vinje1,2
1Simula Research Laboratory, Oslo, Norway.
PloS one
|December 27, 2023
概括
仅仅是大脑表面的脉冲式压力梯度并不能驱动大脑脑膜内流体的流动. 脑膜中的间歇性液体流动主要是由血管网络驱动的,而不是表面压力差异.
科学领域:
- 生物物理学的生物物理.
- 神经科学是一个神经科学.
- 流体动力学 流体动力学
背景情况:
- 内压力 (ICP) 对于大脑的平衡至关重要,并与诸如异常性正常压力头 (iNPH) 这样的疾病有关.
- 一个小的,持久的脉动性穿式压力梯度已经观察到水脑病患者.
- 脉动性内压力的起源及其在流体动力学中的作用需要进一步研究.
研究的目的:
- 调查来自大脑表面的小压力梯度是否可以诱导脉动性内压力和位移.
- 以弹性或可弹性介质为模型,模拟大脑膜膜,以模拟压力动力学.
- 确定大脑脑膜内间歇性液体流动的主要驱动因素.
主要方法:
- 开发了一个基于物理的,高分辨率的脑外的计算模型.
- 模拟了帕伦基马作为线性弹性或弹性材料.
- 在iNPH受试者体内应用的脉动式压力梯度在心室和皮肤表面之间.
主要成果:
- 使用该模型计算了帕伦基马位移,体积变化,流体压力和流体流量.
- 由此产生的位移场是脉动的,并且与弹性和可弹性模型的现有文献一致.
- 在大脑表面边界施加的脉冲力不足以通过脑膜传播压力脉冲.
结论:
- 大脑表面的压力差异本身就不足以驱动大脑外围膜内的间歇性液体流动.
- 这项研究表明,大脑的血管网络,包括较小的血管,是推动间歇性流体流动的压力梯度的更重要的来源.
- 这一发现对理解诸如头等神经疾病中的流体动力学有意义.
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