Zhou Junxiong, Li Yuntao, Tang Jianbo
Guangdong Provincial Key Laboratory of Advanced Biomaterials, Department of Biomedical Engineering, Southern University of Science and Technology, Shenzhen, Guangdong 518055, China.
Contributed equally.
Biomed Opt Express. 2022 Dec 21;14(1):477-488. doi: 10.1364/BOE.469891. eCollection 2023 Jan 1.
Optical coherence tomography angiography (OCTA) for blood vessel 3-D structure imaging suffers from blood vessel projection artifacts/tail artifacts when using a long decorrelation time (e.g., repeat B-scan acquisition in regular OCTA) or loss of micro vessel signal when using a short decorrelation time. In this work, we developed an adaptive first-order field autocorrelation function (g) analysis-based technique to suppress the projection artifacts under macro vessels while enhancing the dynamic signal of micro vessels. The proposed method is based on the differences of the decorrelation rate and the phase variations of g between the vessel voxels and the artifacts regions. A short or long decorrelation time was applied to obtain the dynamic index of the projection artifacts region or the blood vessel region, respectively. Compared to the slab subtraction-based post-image processing-based techniques, the proposed approach addresses this problem on a physical basis and shows the ability to suppress the projection artifacts while enhancing the detection of the micro vessels.
用于血管三维结构成像的光学相干断层扫描血管造影（OCTA），在使用较长去相关时间时（例如常规OCTA中的重复B扫描采集）会出现血管投影伪影/拖尾伪影，而在使用较短去相关时间时会出现微血管信号丢失的情况。在这项工作中，我们开发了一种基于自适应一阶场自相关函数（g）分析的技术，以抑制大血管下的投影伪影，同时增强微血管的动态信号。所提出的方法基于血管体素与伪影区域之间去相关率和g的相位变化的差异。分别应用短或长去相关时间来获取投影伪影区域或血管区域的动态指标。与基于平板减法的图像后处理技术相比，所提出的方法从物理角度解决了这个问题，并显示出在增强微血管检测的同时抑制投影伪影的能力。
