标准化粘度作为脑动脉瘤计算流体动态模拟中的错误来源
Patrick Fillingham1, Neethi Belur1, Rebecca Sweem1
1Department of Neurological Surgery, University of Washington, Seattle, Washington, USA.
Medical physics
|December 27, 2023
概括
在脑动脉瘤计算流体动力学 (CFD) 中标准化血液粘度对结果产生重大影响. 使用患者特异性粘度对于CFD模拟中准确的血液动力学分析至关重要.
科学领域:
- 生物医学工程 生物医学工程
- 医疗成像医学成像
- 流体动力学 流体动力学
背景情况:
- 计算流体动力学 (CFD) 对脑动脉瘤研究至关重要,提供超越成像的血液动力学见解.
- 对CFD的临床应用受限于患者特定数据整合和体内验证方面的挑战.
- 这项研究检查了在CFD模拟脑动脉瘤中标准化血粘度与患者特异性血粘度的影响.
研究的目的:
- 通过使用标准化血液粘度值在脑动脉瘤CFD模拟中量化引入的平均误差.
- 突出结合患者特异性粘度的必要性,以便对脑动脉瘤进行准确的CFD调查.
主要方法:
- 针对41个脑动脉瘤进行了CFD模拟,具有患者特定的边界条件.
- 每个动脉瘤进行了两个模拟:一个是患者特异性粘度 (血红素衍生) 和一个是标准化粘度.
- 计算出血液动力学参数 (WSS,WSSG,OSI) 并使用对联t测试和布兰德-阿尔特曼分析分析差异.
主要成果:
- 在63.2% (WSS),41.5% (WSSG) 和48.7% (OSI) 的动脉瘤中观察到患者特异性和标准化粘度模拟之间的统计学上显著差异.
- 在高于标准粘度或低于标准粘度的组之间,没有发现WSS,WSSG或OSI百分比变化的显著差异.
- 粘度变化和血液动力学参数变化之间没有发现相关性,这表明没有可行的事后纠正.
结论:
- 在CFD模拟脑动脉瘤中标准化血液粘度会导致WSS,WSSG和OSI的实质性,不可预测的变化.
- 建议在所有CFD脑动脉瘤模拟中使用基于血红素的,针对患者的血粘度值.
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