Department of Mechanical Engineering, Pohang University of Science and Technology (POSTECH), 77, Cheongam-ro, Nam-gu, Pohang 37679, Republic of Korea.
Department of Mechanical Engineering, Pohang University of Science and Technology (POSTECH), 77, Cheongam-ro, Nam-gu, Pohang 37679, Republic of Korea.
Ultrasonics. 2020 May;104:106093. doi: 10.1016/j.ultras.2020.106093. Epub 2020 Feb 28.
Color Doppler (CD) ultrasound has been commonly employed in biomedical field to get hemodynamic information. However, reliable diagnostic evaluation and criteria for vascular diseases may not be provided due to technical limitations of CD, including single-directional measurement, aliasing, and limited imaging conditions. In this study, adaptive hybrid (AH) scheme is proposed to enhance measurement accuracy of conventional CD. It can improve the accuracy of velocity field measurement by replacing erroneous vectors in the measured CD results with the correct vectors obtained from a speckle image velocimetry (SIV) technique. The performance of the proposed AH technique was validated through in vitro experiments for various flow rates and insonation angle conditions, comparing conventional velocimetry techniques. The in vitro experiments demonstrated that the AH technique could measure flow velocity with better accuracy than the CD with bias errors of below 0.7 mm/s. The clinical applicability of the AH was also validated by measuring venous flows at human lower extremity, checking constant volumetric flow rates. Flow rates measured by the AH were maintained along the vein, while the CD and SIV results varied. As a result, the AH can provide improved measurement accuracy without installing a new supplementary equipment. It would be effectively utilized for analyzing flow dynamics and diagnosing valve-related disease.
彩色多普勒（CD）超声已广泛应用于生物医学领域，以获取血流动力学信息。然而，由于 CD 的技术限制，包括单向测量、混叠和有限的成像条件，可能无法提供可靠的诊断评估和血管疾病标准。在这项研究中，提出了自适应混合（AH）方案来增强传统 CD 的测量精度。它可以通过用从散斑图像测速（SIV）技术获得的正确矢量替换测量的 CD 结果中的错误矢量，从而提高速度场测量的准确性。通过与传统速度测量技术进行各种流速和入射角度条件的体外实验，验证了所提出的 AH 技术的性能。体外实验表明，与具有低于 0.7mm/s 的偏差误差的 CD 相比，AH 技术可以更准确地测量流速。还通过测量人体下肢的静脉血流来验证 AH 的临床适用性，检查恒定的体积流量。AH 测量的流速沿着静脉保持不变，而 CD 和 SIV 的结果则有所不同。因此，AH 可以在不安装新的补充设备的情况下提供改进的测量精度。它将有效地用于分析流动动力学和诊断与瓣膜相关的疾病。
