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OCT has been widely used to detect glaucomatous structural damage in the parapapillary and macular region. OCT angiography (OCT-A) visualizes the capillary networks in different layers of the retina. Studies have shown that the vessel density as measure by OCT-A is decreased in glaucomatous eyes compared to healthy eyes. This opens the possibility that OCT-A can be used as a tool to diagnose glaucoma. Wan et al. compared the diagnostic performance for detection of glaucoma and the structure-function association between that inner macular vessel density and inner macular thickness. At 90% specificity, the sensitivity of mean inner macular thicknesses for detection of glaucoma was greater than that of mean inner macular vessel densities. In addition, the strength of the structure-function association was stronger for mean inner macular thickness than mean inner macular vessel density. Another noteworthy finding is that 102 and 19 participants were excluded due to poor quality OCT-A and OCT images, respectively. The result of this study contrasts with previous studies which showed a higher or similar diagnostic performance of the inner macular thickness compared with the inner macular vessel density for detection of glaucoma.1-3 The reason of the discrepancy is not clear. One possible source is the application of customized software in this study to standardize the macular area and the macular layers with exclusion of the fovea to compare the diagnostic performance between inner macular vessel density and inner macular thickness, while previous studies used the default setting to define the macular area and layers. Based on the current data and considering the higher frequency of poor quality image for OCT-A, it can be regarded that OCT-A does not have a distinct advantage over OCT for diagnosing glaucoma in its current version.