Schrank E, Phillips D J, Moritz W E, Strandness D E
Department of Electrical Engineering, University of Washington, Seattle, 98195.
Ultrasound Med Biol. 1990;16(5):499-509. doi: 10.1016/0301-5629(90)90172-9.
A triangulation method has been applied to a duplex ultrasound scanner to quantify blood flow velocities in two dimensions. A position locating system (PLS) connected to the scanhead locates the sample volume (SV) in 3-D space to a precision of 1 mm. The PLS is used to obtain flow velocity data from two independent lines of sight in the human femoral artery. Data are gathered from anatomic sites of interest along one line of sight. Later the computer directs the SV to interrogate the same points in space from a second line of sight. Water tank studies using both constant velocity and pulsatile string targets were used to validate the method. Velocity magnitudes could be calculated to within 5% error for Doppler angles below 75 degrees for various string depths and speeds; the error in Doppler angle calculation was usually less than 3 degrees. Results from the superficial femoral artery show flow velocity vectors are nearly parallel to the vessel walls. Peak systolic velocity magnitudes range from 63-66 cm/s in three presumed normal individuals. Following the validation studies addressed in this paper, this triangulation approach is intended in future work to document the complex nonaxial character of blood flow that occurs normally at branch points and in regions of intraluminal disease.
一种三角测量方法已应用于双工超声扫描仪，以在二维空间中量化血流速度。连接到扫描头的位置定位系统（PLS）将样本容积（SV）在三维空间中定位到精确到1毫米的精度。PLS用于从人股动脉的两条独立视线中获取流速数据。沿着一条视线从感兴趣的解剖部位收集数据。随后，计算机引导SV从第二条视线询问空间中的同一点。使用恒速和脉动弦目标的水槽研究用于验证该方法。对于各种弦深度和速度，在多普勒角度低于75度时，速度大小的计算误差可控制在5%以内；多普勒角度计算的误差通常小于3度。股浅动脉的结果显示，血流速度矢量几乎与血管壁平行。在三个假定正常的个体中，收缩期峰值速度大小范围为63 - 66厘米/秒。在本文所述的验证研究之后，这种三角测量方法旨在用于未来的工作，以记录在分支点和管腔内疾病区域正常发生的复杂非轴向血流特征。
