IEEE Trans Med Imaging. 2021 Feb;40(2):758-764. doi: 10.1109/TMI.2020.3036468. Epub 2021 Feb 2.
Conventional color Doppler ultrasound imaging suffers from mutual frequency cancellation when applied to quantify axial blood flow velocities in the rodent brain where inverse flows exist within an ultrasound measurement voxel. Here, we report an improved color Doppler-based functional ultrasound imaging method (iCD-fUS) for axial blood flow velocity imaging of the rodent brain. By applying a directional filter and high frequency noise thresholding, iCD-fUS is able to accurately quantify blood flow velocities within the brain as validated with the ultrasound localization microscopy velocimetry method. We show that iCD-fUS is able to image and resolve the directional axial blood flow velocity throughout the entire coronal section of the brain at a temporal frame rate of up to 10 Hz with a spatial resolution of ~100 [Formula: see text]. We further applied iCD-fUS to image the axial blood flow velocity change in response to whisker stimulation in an awake mouse, showing its potential for studying brain activation. With these capabilities, iCD-fUS provides a powerful, quantitative tool for in vivo chronic research.
传统的彩色多普勒超声成像在应用于量化啮齿动物大脑中存在反向流的轴向血流速度时，会受到相互频率消除的影响。在这里，我们报告了一种改进的基于彩色多普勒的功能超声成像方法 (iCD-fUS)，用于啮齿动物大脑的轴向血流速度成像。通过应用方向滤波器和高频噪声阈值处理，iCD-fUS 能够准确地量化大脑内的血流速度，这已通过超声定位显微镜速度测量方法得到验证。我们表明，iCD-fUS 能够以高达 10 Hz 的时间帧率在整个大脑冠状切片上成像和分辨整个轴向血流速度，空间分辨率约为 100 [Formula: see text]。我们进一步将 iCD-fUS 应用于在清醒小鼠中成像响应胡须刺激的轴向血流速度变化，显示其用于研究大脑激活的潜力。凭借这些功能，iCD-fUS 为体内慢性研究提供了一种强大的定量工具。
