Editor—CADASIL (Cerebral Autosomal Dominant Arteriopathy with Subcortical Infarcts and Leucoencephalopathy) is a hereditary form of multi-infarct vascular dementia.1Clinical symptoms often present in middle adult life (30-50 years of age) and include recurrent subcortical ischaemic strokes, migraine with or without aura, major psychiatric symptoms, and dementia. Magnetic resonance imaging (MRI) shows high intensity signal lesions, often confluent, and areas of cystic degeneration of the subcortical white matter and basal ganglia. Pathological examination shows multiple, small, deep cerebral infarcts, leucoencephalopathy, and a non-atherosclerotic, non-amyloid angiopathy involving mainly the small, deep, perforating cerebral arterioles. Severe alterations of vascular smooth muscle cells are evident on ultrastructural analysis.

The term CADASIL was adopted after linkage of French families with these symptoms to chromosome 19,2 3 but families with many of the features of CADASIL had been described by Worster-Droughtet al 4 5 in the 1930s as familial presenile dementia with spastic paralysis, by Sourander and Walinder6 as hereditary multi-infarct dementia, and by Stevens et al 7 as chronic familial vascular encephalopathy. In 1996, the responsible gene was identified as NOTCH3,8 a member of the Notch …