Based on the correlation analysis of retinal thickness, volume, VD, and PD in the patients with NDR, it can be seen that, in the stage of non-diabetic retinopathy, there is a certain correlation between the microvascular changes and the changes in retinal thickness and volume, and most of them occur in area M. A possible cause might be that in the pathogenesis of DR, endothelial dysfunction and increased leukocyte and ICAM-1 expression are involved in the destruction of the vascular network structure, leading to a series of morphological changes in the FAZ region [45–47]. The gene discussed is ICAM1; the disease is diabetic retinopathy.