In this report, we proposed five metrics, VAD, VSD, VDI, VPI, and VCI, for the quantitative assessment of OCT angiograms. There are several important features in our analytical approach. First, the quantitative OCTA analysis using the five metrics is highly repeatable as the coefficients of variance are all smaller than 0.031, suggesting that the quantitative assessment at follow-up and when used for therapeutic monitoring should provide a high level of accuracy when using OCTA. We showcased repeatability using both a normal case and a BRVO case, with different FOV and scanning location. Second, the quantitative metrics are useful to provide clinicians and physicians with a rapid and comprehensive strategy for interpreting OCT angiograms. Unlike previous studies that only provided a single quantitative index such as VAD or skeleton density, our proposed quantitative analysis includes five indices, e.g., VAD, VSD, VDI, VPI, and VCI. Along with three quantitative maps, the vessel density map, the vessel diameter map, and the vessel complexity map, the information about vascular abnormalities could be visualized and extracted from OCTA images based on multiple perspectives. Vessel length, size, area, perimeter, and morphological complexity can be made all available in one step of image analysis, potentially helping clinicians understand OCTA images better. For example, in the case that we studied here, the five metrics showed its promise to distinguish BRVO from NPDR. Both of these two cases demonstrate VAD decrease. However, for BRVO, the decrease of VAD is dominated by skeleton decline; whereas for NPDR, both VDI and VSD are increased. Third, the quantitative metrics can provide additional information when presented alongside with the qualitative OCTA images.