Ischemic stroke in young adults is rare (5%-10% of all ischemic strokes) and, in absence of other risk factors, may be associated with migraine. We describe the case of a 34-year-old woman, with a history of migraine without aura, who presented a sudden onset of headache with Horner's syndrome, and in whom neuroimaging showed evidence compatible with fibromuscular dysplasia (FMD) and arterial dissection of the extracranial internal carotid artery (ICA) and the carotid siphon. In our opinion, in young women with a long history of migraine, a careful study of the extracranial and intracranial arteries would be useful, although the cost/benefit ratio does not at present justify such a procedure. Our aim in the future is, therefore, to study a larger sample of migraine patients in order to find those patients who are most at risk of arterial dissection and who should, consequently, be carefully studied.