Factors based on optical coherence tomography correlated with vision impairment in diabetic patients

The aim of this study is to evaluate the relationship between retinal structures and visual acuity in diabetic patients using optical coherence tomography (OCT) and OCT angiography (OCTA). This study was a retrospective observational study conducted at a single medical center in Japan. Evaluation of retinal images was analyzed using spectral domain OCT. Twelve factors including central retinal thickness, length of disorganization of retinal inner layer (DRIL), number of inner hyperreflective foci, number of outer hyperreflective foci, height of intraretinal fluid, height of subretinal fluid, length of external limiting membrane disruption, length of external ellipsoid zone (EZ) disruption, vessel density of superficial capillary plexus (SCP), foveal avascular zone (FAZ) area, and FAZ circularity were analyzed based on OCT/OCTA findings. Multivariate analysis was used to investigate the OCT-based factors that could be correlated with poor visual acuity in treatment-naïve diabetic eyes. A total of 183 eyes of 123 diabetic patients with type 2 diabetes (mean age 61.9 ± 12.3 years, 66 men and 57 women) and 62 eyes of 55 control subjects (mean age 64.4 ± 12.5 years, 15 men and 40 women) was enrolled in this study. Multiple regression analysis showed that OCT-based factors correlated with visual acuity were length of DRIL (β = 0.24, P < 0.01), length of EZ disruption (β = 0.35, P < 0.001), and FAZ circularity (β =  - 0.14, P < 0.05). The other factors showed no significant correlation. In conclusion, the length of DRIL, length of EZ disruption, and FAZ circularity measured by OCT were identified as related factors for visual impairment in treatment-naïve diabetic eyes.