Subcortical vascular dementia.

Subcortical vascular dementia (SVD) is a small vessel disease with dementia that exhibits relatively uniform clinical and pathological features and constitutes approximately half of vascular dementia (VaD) cases. This subtype is further classified into Binswanger's disease and multiple lacunar infarctions. The former is characterized by diffuse white matter lesions, and the latter is characterized by lacunar infarctions. Both of these entities are related to hypertensive small vessel changes. Subcortical vascular dementia may exhibit slowly progressive vascular Parkinsonism and dementia but can be differentiated from Alzheimer's disease because it is associated with more extensive white matter lesions, less severe hippocampal atrophy and the absence of cerebral amyloid angiopathy (CAA), which may be indicated radiologically by lobar microbleeds, cortical subarachnoid hemorrhage (SAH) and cortical microinfarctions. Cerebral amyloid angiopathy may manifest as dementia and constitute the cortical type counterpart of SVD in small vessel disease with dementia. This paper provides an overview of the clinical features, pathogenesis and treatment for SVD, as well as its relationship to CAA and Alzheimer's disease.