[A case of spontaneous cervical vertebral artery dissection resulting in Wallenberg's syndrome--diagnostic value of the cervical axial MRI].

Findings of the cervical axial MRI are discussed in a case of spontaneous cervical vertebral artery dissection resulting in Wallenberg's syndrome. A 42-year-old male was hospitalized because of sudden onset of severe occipital pain. Cerebral angiography performed on the day of admission revealed severe tapering stenosis of the right vertebral artery at the C-5 level of the vertebra. Angiography repeated 50 days later showed partial resolution of the narrowing. T-1 weighted axial MRI of the neck demonstrated significantly narrowing flow void of the right vertebral artery when compared with the contralateral side. A crescent-like high intensity area was also seen surrounding the lumen. These findings were consistent with hematoma within the dissected wall of the vertebral artery. MRI is considered useful in identifying such vascular lesions as cerebral artery dissection.