title: Computed tomography; the anatomic basis of the zone of diminished density surrounding meningiomas.
abstract: Computed tomography of meningiomas often demonstrates a zone of diminished density surrounding the actual tumor. This zone may be related to widening of the subarachnoid space, cerebral edema, tissue necrosis, or demyelination. A case is presented in which the anatomic basis of the zone of diminished density was shown on pneumoencephalography and at surgery to be an enlarged subarachnoid space.
mesh_terms: D001932:Brain Neoplasms / Q000000981:diagnostic imaging*; D002533:Cerebral Angiography; D003201:Computers; D005260:Female; D006801:Humans; D008579:Meningioma / Q000000981:diagnostic imaging*; D008875:Middle Aged; D011011:Pneumoencephalography; D013346:Subarachnoid Space / Q000000981:diagnostic imaging; D014056:Tomography, X-Ray