Hoskins P R, Fish P J, McDicken W N, Moran C
Department of Medical Physics & Medical Engineering, Royal Infirmary, Edinburgh, UK.
Med Biol Eng Comput. 1998 May;36(3):259-69. doi: 10.1007/BF02522469.
Many of the changes resulting from arterial disease can be measured, using Doppler ultrasound for measurement of blood velocity and B-scan imaging for measurement of tissue structure and composition. Wall thickness, the degree of arterial narrowing and plaque volume can be measured using B-scan imaging, and 3D ultrasound can be used to improve the accuracy of measurements of plaque volume and for improved visualisation of complex arterial geometries. Measurement of the dynamic properties of the arterial wall permits estimation of wall elasticity and plaque motion. From the Doppler signal, measurements of blood velocity are used to estimate the degree of arterial narrowing and volumetric flow, although measurement errors can be large. Wall shear stress can be estimated by measuring the velocity gradient at the vessel wall. The problems of inadequate spatial resolution and interference from overlying tissue are largely removed when intravascular systems are used, and these have superior capability in the assessment of arterial structure and tissue composition. However, measurement of quantities relating to blood flow is more difficult using the intravascular approach, as the indwelling cather disturbs the blood flow pattern, and currently, assessment of flow and vessel cross-section are not performed at the same site.
许多由动脉疾病引起的变化都可以测量，使用多普勒超声测量血流速度，使用B超成像测量组织结构和成分。可以使用B超成像测量血管壁厚度、动脉狭窄程度和斑块体积，三维超声可用于提高斑块体积测量的准确性，并改善对复杂动脉几何形状的可视化。测量动脉壁的动态特性可以估计壁弹性和斑块运动。根据多普勒信号，血流速度测量用于估计动脉狭窄程度和容积流量，尽管测量误差可能很大。壁面剪应力可以通过测量血管壁处的速度梯度来估计。当使用血管内系统时，空间分辨率不足和来自上层组织干扰的问题在很大程度上得以消除，并且这些系统在评估动脉结构和组织成分方面具有卓越的能力。然而，使用血管内方法测量与血流相关的量更加困难，因为留置导管会干扰血流模式，并且目前，流量和血管横截面的评估并非在同一部位进行。
