Primary intraosseous meningioma: CT and MRI appearance

Abstract

Benign primary intraosseous meningioma presenting with osteolytic skull lesion and soft-tissue component is rare. CT and MR imaging of a patient with frontoparietal scalp swelling showed an osteolytic intracalvarial lesion with an extradural soft-tissue component. Following wide surgical resection, the histological examination revealed an intraosseous chordoid meningioma. The clinical and radiological findings of primary intraosseous meningioma are discussed and the relevant literature is reviewed.

Fig 1.

Plain skull radiograph shows a well-defined solitary lytic lesion in the right frontoparietal region.

Fig 2.

CT scan with bone window (A) demonstrates a right-sided frontoparietal intradiploic mass expanding the calvaria with cortical destruction. Postcontrast CT scan (B) shows prominent enhancement and intracranial extension of the lesion. Three-dimensional reformatted CT image (C) clearly demonstrates the osteolytic skull lesion.

Fig 3.

Sagittal T1-weighted (A) and coronal T2-weighted (B) MR images show the frontoparietal intracalvarial mass lesion that was hypointense on T1-(A) and hyperintense on T2-weighted (B) images. The lesion shows intense and homogeneous enhancement on postcontrast T1-weighted (C) image. MR images (A–C) reveal the intracranial extension and extradural location of the lesion.

Fig 4.

Photomicrograph of the tumor shows the chordoid meningioma with eosinophilic vacuolated tumor cells (large arrow) in a mucous-rich matrix (small arrow) (hematoxylin and eosin, original magnification ×200).