CADASIL: MRI may be normal in the fourth decade of life - a case report.

Background Cerebral autosomal dominant arteriopathy with subcortical infarcts and leukoencephalopathy (CADASIL) manifests by migraine with aura, cerebral ischemic events, mood disturbances and dementia. Brain MRI lesions typically precede the symptoms from 10 to 15 years and previous evidence showed all CADASIL patients above 35 years old have an abnormal MRI, supporting the clinical diagnosis. Case results We present a 37-year-old female patient with migraine without aura, a family history of CADASIL, normal brain 3-Tesla MRI and normal skin biopsy, even though a pathogenic NOTCH3 gene mutation (allele 2, exon 11, c.1672 C\gtT, p.Arg558Cys) was detected. Conclusions When CADASIL is strongly suspected, a normal brain MRI, even in the fourth decade of life, does not rule out the diagnosis and should not discourage the genetic test.