Calcification of the vertebral artery.

A series of 3,648 computed tomographic (CT) scans was reviewed to determine the incidence of intracranial vertebral artery calcification. Calcification was identified in one or both vertebral arteries in 3.4% and was more frequent in the higher age groups. Skull radiographs demonstrated vertebral artery calcification in only one of 48 patients in whom CT studies showed it. A high correlation was observed between vertebral artery calcification on CT and vertebral artery stenosis on cerebral angiography.