障碍的壁切应力在脑动脉瘤发展中的作用
Yuji Shimogonya1, Shunichi Fukuda2,
1Department of Mechanical Engineering, College of Engineering, Nihon University, Koriyama, Japan.
Journal of biomechanics
|October 6, 2024
概括
血流障碍,特别是高正常化横壁剪切应力 (NtransWSS),可能表明脑动脉瘤发展的风险. 这一发现是通过比较患者特定的动脉模型中的模拟血流在动脉瘤发生前后的情况而产生的.
科学领域:
- 生物医学工程 生物医学工程
- 心血管研究研究心血管研究
- 神经科学是一个神经科学.
背景情况:
- 大脑动脉瘤是脑血管疾病的重要原因之一.
- 以前的血液动力学研究没有确定动脉瘤发展的特定危险因素.
- 血液动力学研究中现有的对照组方法可能存在缺陷.
研究的目的:
- 为了确定与脑动脉瘤发育相关的特定血液动力学因素.
- 建立一种新的对照组方法,用于动脉瘤的血液动力学分析.
- 为了研究中脑动脉分叉与动脉瘤形成相关的血液动力学差异.
主要方法:
- 使用患者特定的计算流体动力学 (CFD) 模拟.
- 从中脑动脉几何形状进行了动脉瘤的人工切除.
- 脉动式血流模拟是在动脉瘤前的几何形状 (两侧和两侧侧) 上进行的.
- 进行了血液动力学指标的统计分析,包括正常化的横壁剪切应力 (NtransWSS).
主要成果:
- 统计学上显著的NtransWSS增加被观察到中脑动脉分叉 ipsilateral 动脉瘤部位相比,相反的侧面 (p = 0.01).
- 在其他测试的血液动力学指标中,在双边分叉之间没有发现显著差异.
- 新的对照组方法在突出显著的血液动力学变异方面表现出有效性.
结论:
- 由高的NtransWSS表示的多方向扰乱的壁切应力是脑动脉瘤发展的潜在血液动力学风险因素.
- 这项研究提供了一种精细的方法来调查血液动力学对动脉瘤形成的贡献.
- NtransWSS可以作为大脑动脉瘤风险的预测生物标志物.
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