Multiple primary intraosseous meningioma mimicking fibrous dysplasia: a case report.

Primary intraosseous meningioma (PIM) is a rare subtype of primary extradural meningiomas. These rare ectopic meningiomas have been usually reported in the frontotemporal regions of the calvarium, orbits, and anterior cranial fossa. We report a case with bilateral tumors located in frontoparietal regions of calvarium. Our initial diagnosis was fibrous dysplasia but the lesions were seen to expand under follow-up. One was resected and the histopathological diagnosis was PIM. This is the second reported case of multiple PIM.