School of Control Engineering, Northeastern University at Qinhuangdao, Qinhuangdao, China.
School of Computer Science and Engineering, Northeastern University, Shenyang, China.
J Biophotonics. 2020 Feb;13(2):e201960064. doi: 10.1002/jbio.201960064. Epub 2019 Nov 25.
Doppler optical coherence tomography (OCT) offers additional flow velocity information, which extends the application of OCT. Phase wrapping is the inherent problem that limits measureable range of Doppler OCT. We propose a phase unwrapping method which is suitable for correcting phase in Doppler OCT images. Points (pixels) in flow region are divided into groups according to the radial distance. Points in the same group are supposed to have close velocity. Phase unwrapping algorithm begins at the boundary layer group and is performed sequentially toward the center. Using the proposed criterion, points in a group are separated into two categories, signal points and noise points. Wrapping rounds are determined for signal points phase unwrapping. Mean value of the corrected signal points replaces the noise points for noise reduction. The method is validated with capillary tube flow phantom and in vivo blood flow.
多普勒光相干断层扫描（OCT）提供了额外的血流速度信息，扩展了 OCT 的应用。相位包裹是限制多普勒 OCT 可测量范围的固有问题。我们提出了一种适用于校正多普勒 OCT 图像相位的相位解缠方法。根据径向距离将流区中的点（像素）分为组。假定同一组中的点具有相近的速度。相位解缠算法从边界层组开始，并顺序向中心进行。使用提出的准则，将组中的点分为两类，信号点和噪声点。为信号点的相位解缠确定缠绕轮数。用校正后的信号点的平均值替换噪声点以进行降噪。该方法在毛细管流动体模和体内血流中得到了验证。
