Recurrent silent strokes, with or without clinical strokes, often lead to cognitive decline and overt subcortical dementia. A case of CADASIL presenting as schizophreniform organic psychosis has been reported. Pathophysiology
The underlying pathology of CADASIL is progressive hypertrophy of the smooth muscle cells in blood vessels. Autosomal dominant mutations in the Notch 3 gene (on the long arm of chromosome 19) cause an abnormal accumulation of Notch 3 at the cytoplasmic membrane of vascular smooth muscle cells both in cerebral and extracerebral vessels, seen as granular osmiophilic deposits on electron microscopy. Leukoencephalopathy follows. Depending on the nature and position of each mutation, a consensus significant loss of betasheet structure of the Notch3 protein has been predicted using in silico analysis. Diagnosis
MRIs show hypointensities on T1-weighted images and hyperintensities on T2-weighted images, usually multiple confluent white matter lesions of various sizes, are characteristic. These lesions are concentrated around the basal ganglia, peri-ventricular white matter, and the pons, and are similar to those seen in Binswanger disease. These white matter lesions are also seen in asymptomatic individuals with the mutated gene. While MRI is not used to diagnose CADASIL, it can show the progression of white matter changes even decades before onset of symptoms.The definitive test is sequencing the whole Notch 3 gene, which can be done from a sample of blood. However, as this is quite expensive and CADASIL is a systemic arteriopathy, evidence of the mutation can be found in small and medium-size arteries. Therefore, skin biopsies are often used for the diagnosis.
Ruskin reported in his diaries having visual disturbances consistent with the disease, and it has also been suggested that it might have been a factor in causing him to describe James Whistlers Nocturne in Black and Gold – The Falling Rocket as "ask[ing] two hundred guineas for throwing a pot of paint in the publics face". This resulted in the famous libel trial that resulted in a jurys awarding Whistler one farthing damages.Recent research into the illness of philosopher Friedrich Nietzsche has suggested that his mental illness and death may have been caused by CADASIL rather than tertiary syphilis. Likewise, the early death of the composer Felix Mendelssohn, at age 37, from a stroke has been potentially linked to CADASIL. His sister, Fanny Mendelssohn, was similarly affected. And James Dewar, best known as vocalist for Robin Trower, died age 59 from complications of CADASIL.In the movie The Sea Inside, one of the characters is stated to have CADASIL. See also
Proteopathy
CARASIL (cerebral autosomal recessive arteriopathy with subcortical infarcts and leukoencephalopathy)

References
Further reading
Lesnik Oberstein SA, Boon EM, Terwindt GM (June 28, 2012). CADASIL. University of Washington, Seattle. PMID 20301673. NBK1500. In Adam MP, Everman DB, Mirzaa GM, Pagon RA, Wallace SE, Bean LJH, Gripp KW, Amemiya A (1993). Pagon RA, Bird TD, Dolan CR,  et al. (eds.). GeneReviews [Internet]. Seattle WA: University of Washington, Seattle. PMID 20301295. External links
A patient story at The New York Times