Numerical Fluid-Mechanical Analysis of Accuracy of Ultrasound Doppler Catheter Velocimetry for Measurement of Blood Flow Velocity

超声多普勒导管测速仪血流速度测量精度的数值流体力学分析

• 批准号: 01571241
• 负责人: KAGIYAMA Mitsuyasu
• 金额: $ 1.02万
• 依托单位: Kawasaki College of Allied Health Professions
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for General Scientific Research (C)
• 财政年份: 1989
• 资助国家: 日本
• 起止时间: 1989 至 1990
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-01571241/
• 关键词: Numerical fluid-mechanics; Ultrasound Doppler catheter; Simulation; 数値流体力学; 冠血管

In the previous model-tube experiment, we indicated that 20-MHz ultrsound Doppler catheter velocimetry provides a reliable measure for evaluation relative velocity changes, although it underestimates the blood velocity. To explain this result fluid mechanically, we analyzed the influence of the catheter insertion on the accuracy of Doppler catheter velocimetry by solving numerically the equations of motion for blood flow in a catheterized tube.[Method] A catheterized tube was modeled by a rigid cylindrical tube into which a cylindrical catheter is inserted coaxially. We assumed that fluid is incompressible and Newtonian, and that flow is axisymmetric in the tube. Velocity distribution of the steady flow in the tube was calculated by solving the vorticity and stream function equations transformed from two dimensional Navier-Stokes equations and continuity equation in a cylindrical coordinate system. Dufort and Frankel's method was used to solve the velocity equation, and Liepmann's method was used to solve the stream function iteratively.[Results] Calculations were carried out under the assumption that (1) the flow direction is away from the catheter tip, (2) the inner diameter of the vessel is 7mm, (3) the size of the catheter is 1mm and (4) the Reynolds number is 400. The velocity profile was M-shaped or blunt pattern across the vessel at 1-3 tubular diameter from the catheter tip. The center line velocity was depressed up to 8-10 tubular diameters distal to the catheter tip.[Concluding Remarks] The M-shaped or blunt flow pattern may be the major cause for greater under-estimation of away flow velocity than that of toward-flow velocity.

在之前的模型管实验中，我们表明 20 MHz 超声多普勒导管测速法为评估相对速度变化提供了可靠的测量方法，尽管它低估了血流速度。为了从流体力学上解释这一结果，我们通过数值求解插管内血流的运动方程，分析了导管插入对多普勒导管测速精度的影响。[方法]用刚性圆柱管对插管进行建模。圆柱形导管同轴地插入其中。我们假设流体是不可压缩的牛顿流体，并且流动在管中是轴对称的。通过在圆柱坐标系下求解二维纳维-斯托克斯方程和连续性方程转化的涡量和流函数方程，计算管内稳定流的速度分布。采用Dufort和Frankel法求解速度方程，采用Liepmann法迭代求解流函数。[结果]计算时假设(1)流向远离导管尖端，(2 ) 血管内径为 7mm，(3) 导管尺寸为 1mm，(4) 雷诺数为 400。速度分布呈 M 形或钝形距离导管尖端 1-3 管状直径的血管。中心线速度在导管尖端远端降低了 8-10 个管直径。 [结论] M 形或钝流型可能是远流速度比流流速度低估更大的主要原因。流速。

项目成果

Shinichiro Tadaoka: "Accuracy of 20ーMHz Doppler Catheter Coronary Artery Velocimetry for Measurement of Coronary Blood Flow Velocity" Catheterization and Cardiovascular Diagnosis. 19. 205-213 (1990)

Shinichiro Tadaoka：“20 MHz 多普勒冠状动脉测速仪测量冠状动脉血流速度的准确性”导管插入术和心血管诊断。19. 205-213 (1990)

忠岡 信一郎: "ドプラカテ-テルを用いた冠血流計測の問題点と臨床応用" 医用電子と生体工学. 27. 385-385 (1989)

Shinichiro Tadaoka：“使用多普勒导管测量冠状动脉血流的问题和临床应用”医疗电子和生物工程 27. 385-385 (1989)。

忠岡信一郎: "20MHzドプラカテ-テルを用いた冠血流計測の問題点と臨床応用" 医用電子と生体工学. 27,(特別号). 385 (1989)

Shinichiro Tadaoka：“使用 20MHz 多普勒导管测量冠状动脉血流的问题和临床应用”《医疗电子和生物工程》27，（特刊）385（1989）。

忠岡 信一郎: "ドプラカテ-テルを用いた冠血流計測の問題点と臨床応用" 医用電子と生体工学. 27. 385-385 (1989)

Shinichiro Tadaoka：“使用多普勒导管测量冠状动脉血流的问题和临床应用”医疗电子和生物工程 27. 385-385 (1989)。

Shinichiro Tadaoka: "Accuracy of 20-MHz Doppler Catheter Coronary Artery Velocimetry for Measurement of Coronary Blood Flow Velocity" Catheterization and Cardiovascular Diagnosis. 27. 205-213 (1990)

Shinichiro Tadaoka：“20 MHz 多普勒导管冠状动脉测速仪测量冠状动脉血流速度的准确性”导管插入术和心血管诊断。