UNASSIGNED: Separate femoral bifurcation models were built for oPIV and ePIV measurements of a non-stenosed (control) and a 75%-area stenosed common femoral artery. A flow loop was used to create triphasic pulsatile flow. In-plane velocity vectors were measured with oPIV and ePIV. Flow was simulated with CFD using boundary conditions from ePIV and additional duplex-ultrasound (DUS) measurements. Mean differences and 95%-limits of agreement (1.96*SD) of the velocity magnitudes in space and time were compared, and the similarity of vector complexity (VC) and time-averaged wall shear stress (TAWSS) was assessed.
UNASSIGNED: Similar flow features were observed between modalities with velocities up to 110 and 330 cm/s in the control and the stenosed model, respectively. Relative to oPIV, ePIV and CFD-ePIV showed negligible mean differences in velocity (<3 cm/s), with limits of agreement of ±25 cm/s (control) and ±34 cm/s (stenosed). CFD-DUS overestimated velocities with limits of agreements of 13±40 and 16.1±55 cm/s for the control and stenosed model, respectively. VC showed good agreement, whereas TAWSS showed similar trends but with higher values for ePIV, CFD-DUS, and CFD-ePIV compared to oPIV.
UNASSIGNED: EPIV and CFD-ePIV can accurately measure complex flow features in the femoral bifurcation and around a stenosis. CFD-DUS showed larger deviations in velocities making it a less robust technique for hemodynamical assessment. The applied ePIV and CFD techniques enable two- and three-dimensional assessment of local hemodynamics with high spatiotemporal resolution and thereby overcome key limitations of current clinical modalities making them an attractive and cost-effective alternative for hemodynamical assessment in clinical practice.
■建立单独的股分叉模型,用于非狭窄(对照)和75%面积狭窄的股总动脉的oPIV和ePIV测量。使用流动回路来产生三相脉动流。使用oPIV和ePIV测量面内速度矢量。使用来自ePIV的边界条件和额外的双超声(DUS)测量,用CFD模拟流动。比较了空间和时间上速度大小的平均差异和95%-一致性极限(1.96*SD),并评估了矢量复杂度(VC)和时间平均壁切应力(TAWSS)的相似性。
■在对照和狭窄模型中,在速度高达110和330cm/s的模态之间观察到类似的流动特征,分别。相对于oPIV,ePIV和CFD-ePIV显示出可忽略的平均速度差异(<3cm/s),符合范围为±25cm/s(对照)和±34cm/s(狭窄)。CFD-DUS高估了控制和狭窄模型的速度,协议限制为13±40和16.1±55cm/s,分别。VC表现出良好的一致性,而TAWSS显示出类似的趋势,但ePIV值较高,CFD-DUS,和CFD-ePIV与oPIV相比。
■EPIV和CFD-ePIV可以准确测量股骨分叉和狭窄周围的复杂血流特征。CFD-DUS显示出较大的速度偏差,使其成为血液动力学评估的较不可靠的技术。应用的ePIV和CFD技术能够以高时空分辨率对局部血液动力学进行二维和三维评估,从而克服了当前临床模式的关键限制,使其成为临床实践中血液动力学评估的有吸引力且具有成本效益的替代方法。