Small-vessel disease related to subcortical dementia is one of the main subtypes of the vascular dementia (VaD) syndrome. The early cognitive features of subcortical vascular dementia (SVD) are characterized by a dysexecutive syndrome with slowed information processing, usually mild memory deficit and behavioral symptoms. SVD incorporates two entities "the lacunar state" and "Binswanger's disease". Cerebral amyloid angiopathy (CAA) falls into the category of small-vessel diseases and contributes to the SVD syndrome. Cerebral autosomal dominant arteriopathy with subcortical infarcts and leukoencephalopathy (CADASIL) is the most common form of hereditary small-vessel diseases leading to cognitive decline and dementia. Small-vessel diseases of the brain may also manifest in progressive visual impairment. Hereditary endotheliopathy with retinopathy, nephropathy and stroke (HERNS), cerebroretinal vasculopathy (CRV) and hereditary vascular retinopathy (HVR) were reported independently, but are different phenotypes in the same disease spectrum.