[Osteoid oteoma associated with intraosseous meningioma. A case report]

A very rare case of intraosseous meningioma accompanied with osteoma is reported. A 57-year-old male was admitted with left chronic subdural hematoma and an operation was immediately performed. At the time of admission skull X-ray film showed a high density area in the right frontoparietal region. Postoperative CT scanning showed no abnormality at standard window, widths and levels or at higher window, widths and levels. 99m Tc MPP scinti gram showed increased activity in the right frontoparietal region. Tomography of the skull indicated hyperostosis involving all layers. This skull tumor was diagnosed as osteoma. At the second operation the osteoma was removed. There seemed to be no changes in the bone and underlying dura. Histological examination indicated multiple microscopic meningotheliomatous meningioma with psammoma bodies in Haversian canals, leading to the conclusion that this was osteoid osteoma. It is suggested that this case be designated as type Lopez II and that it raises some interesting points regarding histogenesis and development of meningioma.