Leukoaraiosis is a radiological diagnosis referring to rarefaction of white matter and describes brain pathology characterized by diffuse, confluent white matter abnormalities, typically in the periventricular regions of the brain. Most associated with disease of the small vessels, leukoaraiosis is thought to reflect chronic low-level ischemia in combination with blood-brain barrier dysfunction. Additionally, it may be associated with blood vessel abnormalities, other ischemic events, edema, and cerebral amyloid angiopathy. The underlying pathology includes myelin pallor, enlargement of perivascular spaces, gliosis, axonal loss, and ischemic demyelination. Vascular risk factors, such as hypertension, heart disease, or diabetes, and increasing age are risk factors for developing leukoaraiosis. Leukoaraiosis is detectable by high-frequency CT and...