Evaluation of the vertebrobasilar artery system by magnetic resonance angiography in the diagnosis of vertebrobasilar insufficiency.

To evaluate the advantages of magnetic resonance angiography (MRA) in assessing the vertebrobasilar artery system for diagnosing vertebrobasilar insufficiency (VBI), we compared the MRA results of middle-aged and older VBI cases with those of age-matched peripheral disorder cases. There were no significant differences in the rate of complications associated with atherosclerosis between VBI cases and peripheral disorder cases. The MRA results were quantitatively assessed by scores determined on the basis of the severity of stenosis in the vertebral arteries and basilar artery. The MRA score was defined as the total score of these three arteries. The severity of stenosis and the MRA score of VBI cases were significantly higher than those of peripheral cases. MRA can therefore be of value as a screening examination for estimating vertebrobasilar blood flow and can provide helpful information for diagnosing VBI.