Intraosseous meningioma with a dural defect.

A 56-year-old female presented with a rare intraosseous meningioma associated with an unusual dural defect caused by invasion of the tumor. The underlying dura mater is normal or thickened in most cases of intraosseous meningiomas. Most intraosseous meningiomas are benign histologically, but they should be extirpated before invasion into the subdural space occurs.