[Extracalvarial meningioma--report of a case (author's transl)].

A case of extracalvarial meningioma was reported. 75-year-old man was admitted to our department on November 11, 1974 because of a slowly growing tumor in the right frontoparietal area. The tumor was ovoid and 15x13 cm in size, protruding 5 cm above the skin level, and covered by the normal scalp. Neurological and electroencephalographic examination were negative. Spinal tap showed an opening pressure of 90 mm of water and clear CSF with 62 mg/dl of protein content. Plain roentgenogram and laminagram of the skull revealed both osteolytic and osteoblastic change in the outer and inner table of the skull just beneath the tumor. A right external carotid angiography disclosed a homogeneous extracalvarial tumor stain supplied by the superficial temporal artery and draining into the superficial temporal vein. A right carotid angiogram showed a 1 cm thick avacular area. The segmentally occluded superior sagittal sinus was displaced inward together with bridging collateral channels. Radiologically these picture corresponded to "intracranial non-globoid shape or avascular meningioma" discussed by Huckman et al. The tumor was well-circumscribed, encapsulated and loosely adherent to the periosteum and the skull except for a small portion through which the tumor was communicated with its intracranial part. Histological examination revealed that it was a typical endotheliomatous meningioma. This case should be allocated to the transitional or intermediate type between Lopez II and III type. In the schematical presentation (Fig. 6) we tried to readjust the rather confusing concept and classification of the extracalvarial meningioma.