In the POAG group, the univariate regression analysis using the Pearson correlation coefficient showed that optic nerve head vessel density was significantly correlated with VF MD (r = 0.829, p<0.001), VF PSD (r = 0.47, p = 0.04), and RNFL thickness (r = 0.512, p = 0.04). Also superior papillary area vessel density was significantly correlated with superior RNFL thickness (r = 0.436, p = 0.02), inferior papillary area vessel density was significantly correlated with inferior RNFL thickness (r = 0.523, p = 0.04).