[Subependymal tumor with metaplastic bone formation: a case report].

A 26-year-old woman was admitted to our hospital because of headache. CT scan and MRI showed a right subependymal nodule and a left ventricular tumor, neither of which had any enhancement nor were they stained in angiography. Although no skin abnormality was detected, the patient was suspected of tuberous sclerosis. The diagnosis was made because of the subependymal nodule on CT scan and MRI. On June 29, 1995, total removal of a left ventricular tumor was performed by a transcortical approach. Histological sections of this tumor consisted of astrocytic and meningothelial components, containing metaplastic bone formation. Histological diagnosis was dysplastic subependymal tumor. Postoperative course was uneventful. Regrowth of the tumor has not been observed as of now. This case was suspected to involve factors of tuberous sclerosis from a subependymal nodule. However, the ventricular tumor was not diagnosed as a subependymal giant cell astrocytoma.