Long-standing vascular compression on the medulla as diagnosed by metrizamide CT cisternography

The authors report two cases which had long been considered degenerative disorders. In both cases, metrizamide CT cisternography revealed a lesion compressing the medulla, while angiography identified an aneurysm of the posterior inferior cerebellar artery and the elongated vertebral artery respectively. The report emphasizes the importance of metrizamide CT cisternography before a diagnosis of degenerative disorder of the brain stem is made. (author)