肺部自体移植中的血液动力学和壁剪线指标:比较流体结构相互作用和计算流体动力学方法
Amith Balasubramanya1, Lauranne Maes2, Filip Rega3
1IBiTech-BioMMedA, Ghent University, Ghent, Belgium.
Computers in biology and medicine
|May 18, 2024
概括
流体结构相互作用 (FSI) 建模与计算流体动力学 (CFD) 相比,准确地预测肺部自移植 (PA) 血动力学和壁剪压力 (WSS). 由于复杂的流动动力学,FSI对于理解PA增长和重塑至关重要.
科学领域:
- 生物医学工程 生物医学工程
- 心血管力学心血管力学
- 计算生物学 计算生物学
背景情况:
- 年轻患者的大动脉疾病往往需要肺自移植 (PA) 替换.
- 在血动力学力量的影响下,PA通过生长和重塑来适应其新环境.
- 在急性手术阶段了解这些力量对于预测PA结果至关重要.
研究的目的:
- 开发和验证流体结构相互作用 (FSI) 框架,用于分析PA上的血液动力学力.
- 为了比较FSI衍生的血液动力学和壁剪应力 (WSS) 度量与传统的计算流体动力学 (CFD) 模拟.
- 评估FSI适合用于模拟PA适应和改造的适合性.
主要方法:
- 开发了一种FSI框架,将高弹性动脉组织模型与使用CoCoNuT代码的流体模型合起来.
- 利用体内测量用于几何,材料特性和边界条件.
- 在羊模型中评估了血液动力学,时间平均WSS (TAWSS),振荡剪切指数 (OSI) 和拓剪切变化指数 (TSVI).
主要成果:
- FSI和CFD之间的高点对点相关性 (TAWSS的r>0.9,OSI的r>0.8),尽管PA量有显著的变化.
- 由于大PA变形,TSVI的相关性降低 (r < 0.7),表明FSI对几何变化的敏感性.
- 对于低TAWSS和高OSI/TSVI值,FSI和CFD之间的温和协议.
结论:
- FSI提供了一个强大的方法来模拟PA血动力学和WSS,与CFD密切匹配关键指标.
- FSI捕捉大变形的能力对于准确评估TSVI至关重要,TSVI是PA增长和重塑的潜在驱动力.
- 建议使用FSI建模来研究PA手术后适应的机理生物学机制.
关键词:
计算流体动力学的流体动力学.流体结构相互作用的相互作用血液动力学 血液动力学振荡式剪切指数的指数肺部自体移植 肺部自体移植时间平均的墙壁剪切应力.拓切割变化指数的拓切割变化指数墙壁剪切应力分歧的分歧更多相关视频
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