Sporadic hemiplegic migraine with normal imaging as the initial manifestation of CADASIL.

Background: Cerebral autosomal dominant arteriopathy with subcortical infarcts and leukoencephalopathy (CADASIL) can be present with negative family history and, especially in younger patients, with normal brain magnetic resonance. For this reason, those CADASIL patients that present only with migraine may be misdiagnosed. In the case of migraine with motor aura, sporadic hemiplegic migraine (SHM) is one of the possible misdiagnoses.

Case Results: We present a case of a patient who, in the first years of her disease, met the clinical criteria for SHM. A diagnosis of CADASIL was considered only when her sister presented with headache and an unknown leukoencephalopathy.

Conclusions: This case illustrates the need for a careful review of the clinical and family history during the follow-up of primary headaches.