EDN1 and snowflake vitreoretinal degeneration: In the deep parietal white matter in an elderly cohort that included AD, VaD and cognitively normal cases, MAG:PLP1 showed a highly significant negative correlation with severity of SVD and a highly significant positive correlations with the concentration of the vasoconstrictor endothelin-1 (EDN1) and with the concentration of vascular endothelial growth factor (VEGF) [11, 12].