Giant Intraosseous Meningioma Associated with Calvarial Hyperostosis and Subcutaneous Invasion: Case Reports and Literature Review.

Most meningiomas grow intracranially, and primary intraosseous meningioma is rarely reported. We present two rare surgical cases of giant intraosseous meningothelial meningioma. The first patient was a 35-year-old male with parietal skull deformity without neurological symptoms. Total resection was successful. The origin was the parasagittal intraosseous layer, and the superior sagittal sinus was partially opened. The second patient was a 20-year-old female with a slightly upward protrusion of the frontal skull without pain or neurological deficits. The lesion was totally resected, and the origin was the parasagittal intraosseous layer invading into the dura matter and subcutaneous layer. The clinical management of these cases presented a surgical challenge because of detachment and repair from venous sinuses. The current report provides surgical tips for such rare diseases and is a good reference for the future treatment of similar diseases.