Repeatability and Reproducibility of Quantitative Assessment of the Retinal Microvasculature Using Optical Coherence Tomography Angiography Based on Optical Microangiography

Objective The aim of this study was to determine the repeatability and reproducibility of optical coherence tomography angiography (OCTA) based on optical microangiography (OMAG) measurements of macular vessels in normal eyes. Methods In this prospective cohort study, 40 eyes of 40 healthy volunteers underwent repeated OCTA (Cirrus HD-OCT 5000 angiography system, Carl Zeiss Meditec, Inc.) scans on two separate visit days. On each visit day, the eyes were scanned three times. The following parameters were used to quantitatively describe the OCTA images of the superficial vascular network:vessel area density (VAD), vessel skeleton density (VSD), vessel diameter index (VDI), vessel perimeter index (VPI), vessel complexity index (VCI), flux, and foveal avascular zone (FAZ). Coefficient of variation (CV) and intraclass correlation coefficient (ICC) were calculated for evaluating intravisit and intervisit repeatability, as well as interobserver reproducibility. Results The measurements showed high repeatability[CVs ≤ 4.2% (intravisit) and ≤ 4.6% (intervisit)] and interobserver reproducibility (ICCs ≥ 0.923) for all parameters. Conclusion This study demonstrated good repeatability and reproducibility of OCTA based on OMAG for the measurement of superficial vessel parameters in normal eyes.