Relationship between visual acuity and OCT angiography parameters in diabetic retinopathy eyes after treatment

Purpose To assess the relationship between visual acuity and OCT angiography parameters in diabetic retinopathy eyes after treatment, and to analyze the relative factors in PDR eyes. Methods A total of 89 eyes, including 42 eyes with non-PDR (NPDR), and 47 eyes after vitrectomy with PDR were included and underwent OCTA. All images were processed by Python or FIJI. Multivariable linear regression models were used to analyze the associations between postoperative BCVA and OCTA parameters in PDR patients. Results Postoperative OCTA parameters including deep capillary plexus (DCP) parafoveal and perifoveal vessel density (VD), DCP parafoveal and perifoveal vessel length density (VLD), DCP fractal dimension (FD), choriocapillaris plexus (CCP) VD, CCP VLD, were significantly lower in the PDR group than in the NPDR group. In the superficial capillary plexus (SCP), we found a negative correlation between the postoperative BCVA and VD (parafovea: β coefficient = -0.351, p = 0.023; perifovea: β coefficient = -0.338, p = 0.036). Perifoveal VLD (β coefficient = -0.343, p = 0.031) and FD (β coefficient = -0.375, p = 0.016) of the SCP were also negatively correlated with postoperative BCVA. Regarding the DCP, perifoveal VD (β coefficient = -0.396, p = 0.008), perifoveal VLD (β coefficient = -0.334, p = 0.025), vessel tortuosity (VT) (β coefficient = -0.369, p = 0.015) were negatively correlated with postoperative BCVA. In CCP, VLD (β coefficient = -0.373, p = 0.023) and number of flow voids (β coefficient = -0.334, p = 0.036) exhibited a negative association with postoperative BCVA. Conclusions Postoperative BCVA of PDR patients was related to OCTA parameters of the SCP (parafoveal and perifoveal VD, perifoveal VLD and FD), DCP (perifoveal VD, VLD, and VT) and CCP (VLD and number of flow voids).