Magnetic Resonance Angiography for Patients with Positional Vertigo.

Magnetic resonance angiography (MRA) can image the blood vessels without invasion. Using MRA, we studied the vascular morphology of the vertebral artery in patients with positional nystagmus and vertigo. Fifteen patients without vestibular disorder such as benign positional vertigo were examined. Six cases underwent conventional vertebral angiograpy, including digital subtraction angiography (DSA) for comparison with MRA.In all cases, we observed the vertebral artery from the bifurcation to the basilar artery with MRA. In 12 cases, abnormal findings of elongation, bending, narrowing or obstruction of the vertebral artery were found. In five cases, arterial compression and elongation increased in association with head rotation. A difference in the vessel diameter on each side was observed in 4 cases. Accordingly, some abnormal vessels were found in 14 of 15 cases in our study. This rate was very close to previous resolts obtained with conventional angiography.In two cases, MRA findings differed from conventional angiography due to peculiar artifacts of MRA. Therefore, MRA may be the first choice for the patients with vertigo, followed by conventional angiography, if necessary.