CADASIL (Cerebral Autosomal Dominant Arteriopathy with Subcortical Infarcts and Leukoencephalopathy) is a rare genetic disorder that affects the small blood vessels in the brain. It is caused by mutations in the Notch 3 gene. The age of onset, severity, specific symptoms, and disease progression vary greatly from one person to another, even among members of the same family. However, signs typically appear in people between the ages of 20 and 40 years, although some individuals may not show signs until later in life. Symptoms of CADASIL include migraines, multiple strokes progressing to dementia, decline in memory and thinking skills (cognitive deterioration), seizures, and vision problems. The disease progresses to subcortical dementia associated with pseudobulbar palsy and urinary incontinence. While there is no cure or effective treatment for CADASIL, supportive care, including practical help, emotional support, and counseling, is useful for affected people and their families. Migraines should be treated both symptomatically and with preventative methods, depending on the individual.