CT features of hyperostosing meningioma en plaque.

Hyperostosis of the sphenoid ridge or convexity of the skull associated with meningioma en plaque (MEP) is often confused with other hyperostosing conditions, such as fibrous dysplasia or osteoma. The authors present nine cases, six of them proven, of hyperostosing MEP with specific attention to the CT features. All nine cases had one or more CT features that were characteristic or suggestive of MEP. These included periosteal pattern of hyperostosis, inward bulging of the vault lesion, surface irregularity of the hyperostotic bone, and intracranial changes. The role of CT in evaluating MEP is compared with other neuroradiologic techniques. The results indicate that high-resolution CT is the neuroimaging method of choice in evaluating MEP.