42-year-old
with pathologically proven grade 1 meningioma. Noncontrast axial CT (A) shows a
large, radiodense bifrontal mass. On transverse axial T2-weighted MRI (B), the
mass has homogeneous signal intensity and is surrounded by a thin
T2-hyperintense "CSF cleft" (C, arrows). On coronal CT with bone
windowing (D), there is faint hyperdensity along the midline floor of the
anterior cranial fossa (arrowhead), consistent with hyperostosis. Postcontrast
MRI in the coronal plane (E) demonstrates an intensely and homogeneously
enhancing meningioma with an area of hypoenhancement (thick arrow) that
corresponds to hyperostosis.
CSF:
cerebrospinal fluid; CT: computed tomography; MRI: magnetic resonance imaging.