Department of Biomedical Imaging and Radiological Science, China Medical University, Taichung, Taiwan.
Microvasc Res. 2011 Jan;81(1):68-72. doi: 10.1016/j.mvr.2010.10.006. Epub 2010 Nov 1.
Red blood cell (RBC) dynamics in capillaries is a useful diagnostic tool for many diseases. Previous study showed that optical flow estimation (OFE) is capable of accurately calculating RBC velocities using image registration technique. The computational fluid dynamics (CFD) method is explored in this study to calculate the RBC velocity in capillaries of finger nail-fold for six cases. The two-dimensional capillary images were reconstructed to three-dimensional, assuming circular cross sections. The no-slip boundary conditions were applied on the vessel walls. The initial velocity of the RBC going into each capillary was calculated by OFE. The velocities of multiple points along each capillary calculated by CFD, V(CFD), were compared with OFE calculations, V(OFE). The calculated RBC velocity was in the range of 56-685μm/s. The average difference (V(CFD) - V(OFE)) with one standard deviation is -2.66±18.61μm/s for all the 48 calculation points, and 0.03±0.12μm/s for all except one points (47 points), indicating that CFD can provide a reasonable accuracy in RBC velocity calculation in finger nail-fold capillaries.
红细胞（RBC）在毛细血管中的动力学是许多疾病的有用诊断工具。先前的研究表明，光流估计（OFE）能够使用图像配准技术准确计算 RBC 速度。本研究探索了计算流体动力学（CFD）方法，以计算指甲襞毛细血管中的 RBC 速度，共涉及六个案例。二维毛细血管图像被重建为三维图像，假设为圆形横截面。在血管壁上施加无滑移边界条件。通过 OFE 计算进入每个毛细血管的 RBC 的初始速度。通过 CFD 计算沿每个毛细血管的多个点的速度，V（CFD），并与 OFE 计算进行比较，V（OFE）。计算出的 RBC 速度在 56-685μm/s 范围内。所有 48 个计算点的平均差异（V（CFD）-V（OFE））为 18.61μm/s，除一个点（47 个点）外，所有点的平均差异为 0.03μm/s，表明 CFD 可以在指甲襞毛细血管中提供合理的 RBC 速度计算精度。
