Angiographic spectrum of cervical and intracranial fibromuscular dysplasia.

Cephalocervical or intracranial fibromuscular dysplasia (FMD) can be identified by its characteristic angiographic appearance. Most of these lesions occur adjacent to the C1-2 interspace, characteristically sparing the origins and proximal segments of the major extracranial vessels. Approximately 65% of our patients had bilateral involvement of the cervical internal carotid arteries. Thirty percent were associated with one or more intracranial aneurysms. The vertebral arteries were involved in 10% of the cases. Twenty-four of 25 cases were associated with symptoms of either subarachnoid hemorrhage or focal cerebral ischemia.