Which one of the following tumors shows calcification on CT Scan?
High-Yield Explanation
Calcification on CT scan is a typical feature of meningioma. It is also seen in ependymoma, but is specific for meningioma. Meningioma is a malignancy arising from the meningeal layers. It typically present as an incidental, extra axial mass lesions or may present with specific signs and symptoms often in middle age females. It arise over the cerebral convexity, sphenoid wings, cavernous sinus, tuberculum and foramen magnum. Typical imaiging features of meningioma are: Calcification: 30% of meningiomas are fully calcified on CT. Calcification occur in forms such as psammomatous/sand like, focal, diffuse or rim type. Hyperostosis: Extra axial mass with skull hyperostosis is highly suggestive of meningioma. Dura tail sign: 60% of meningiomas manifest dura tail sign. A broad dural attachment of a tumor with an adjacent dural tail is highly suggestive of meningioma. Radial sunburst pattern: Globose, extra axial mass with radiating linear hypointense signal from the center to periphery in a sunburst pattern on angiography and persistent angiographic blush indicate highly vascular nature of meningioma. Ref: Meningiomas: Diagnosis, Treatment and Outcome By Joung H. Lee, Pages 67-8; Principles and Practice of Neuro-Oncology: A Multidisciplinary Approach By Minesh P. Mehta, Page 801; Principles and Practice of Pediatric Neurosurgery By A. Leland Albright, 2nd Edition, Page 607; Learning Neuroimaging: 100 Essential Cases By Francisco de Asis, Page 175