Cerebral autosomal dominant arteriopathy with subcortical infarcts and leukoencephalopathy: an imaging mimic of multiple sclerosis. A report of two cases.

OBJECTIVE AND IMPORTANCE To describe the imaging findings of two cases of cerebral autosomal dominant arteriopathy with subcortical infarcts and leukoencephalopathy (CADASIL) mimicking multiple sclerosis. CLINICAL PRESENTATION AND INTERVENTION Two cases presenting with neurological signs and symptoms were referred for magnetic resonance imaging (MRI) evaluation of the brain. Case 1 was a 36-year-old female patient presenting with recurrent headaches and recent onset numbness in the fingers of the right hand. Neurological examination showed a mild sensory deficit in the right hand. Case 2 was a 31-year-old female patient presenting with attacks of right-sided numbness of the face and body. The neurological examination revealed a sensory loss in the face and brisk deep tendon reflexes. Routine MRI sequences showed two types of lesions in both cases: 'punctate' hyperintense lesions on T(2)-weighted images (T(2)WI)/fluid-attenuated inversion recovery (FLAIR) images, hypointense on T(1)-weighted images (T(1)WI) and 'diffuse' white matter lesions, hyperintense on T(2)WI/FLAIR sequences and isointense to hypointense on T(1)WI. All lesions showed no contrast enhancement. Both cases were previously clinically and radiologically diagnosed as multiple sclerosis. There was a strong family history consistent with recurrent infarctions in other family members of both patients. Both cases were later diagnosed as CADASIL by skin biopsy/genetic linkage studies and follow-up. CONCLUSION The cases showed that CADASIL causes stroke-like episodes in adults and can mimic multiple sclerosis on imaging. Clinical evaluation and MRI findings allow a differentiation of the two entities.