Tardy Y, Hayoz D, Mignot J P, Richard P, Brunner H R, Meister J J
Biomedical Engineering Laboratory, Swiss Federal Institute of Technology, Lausanne.
J Hypertens Suppl. 1992 Aug;10(6):S105-9.
Non-invasive measurements of arterial diameter and wall thickness are critical in characterizing the onset and development of vascular disease. A precise dynamic method was proposed and tested for this purpose.
A non-invasive method of measuring the variations in diameter and thickness of human arteries throughout the cardiac cycle was developed, using a high-precision ultrasonic echo-tracking system. An adaptive filtering technique was used to suppress artefacts caused by the layered tissue structure of the vessel wall.
Based on decorrelation of microstructure noise, this technique improved the detectability of the wall interfaces, which allowed a determination of thickness and diameter. The accuracy and reproducibility of the method were tested by measurements of plastic films with known thicknesses. The discrepancies between standard micrometer and pulse-echo measurement were consistently less than 5 microns for film thicknesses ranging from 220 to 800 microns. The difference between two successive measurements was less than 2 microns. The identity of the measured vascular interfaces was checked in two ways. First, experiments on fixed bovine carotid arteries showed that the identified echogenic interfaces corresponded to the actual anatomical structure, as obtained by acoustic microscopy. Second, the radial artery thickness and diameter were extrapolated to obtain the change in wall volume over one cardiac cycle. The volume was found to be nearly constant, indicating incompressibility.
This method will make it possible to obtain new information on atherogenesis and other vascular diseases.
动脉直径和壁厚度的无创测量对于表征血管疾病的发生和发展至关重要。为此提出并测试了一种精确的动态方法。
利用高精度超声回波跟踪系统，开发了一种在整个心动周期测量人体动脉直径和厚度变化的无创方法。采用自适应滤波技术抑制由血管壁分层组织结构引起的伪像。
基于微观结构噪声的去相关，该技术提高了壁界面的可检测性，从而能够确定厚度和直径。通过测量已知厚度的塑料薄膜对该方法的准确性和可重复性进行了测试。对于厚度在220至800微米范围内的薄膜，标准千分尺测量值与脉冲回波测量值之间的差异始终小于5微米。两次连续测量之间的差异小于2微米。通过两种方式检查所测量血管界面的一致性。第一，对固定的牛颈动脉进行实验表明，所识别的回声界面与通过声学显微镜获得的实际解剖结构相对应。第二，外推桡动脉的厚度和直径以获得一个心动周期内壁体积的变化。发现该体积几乎恒定，表明不可压缩。
该方法将有可能获得关于动脉粥样硬化形成和其他血管疾病的新信息。
