Endotheliomatous meningioma with coalescing microcysts, presenting as an hypodense lesion with ring enhancement on computed tomography.

Computed tomography (CT) revealed a hypodense intracranial tumour that showed a slight ring enhancement and a peripheral tumour nodule. Although this suggested a cystic astrocytoma, angiography identified a meningeal tumour. Microscopical examination demonstrated a cystic endotheliomatous meningioma. Neuropathological and intraoperative findings suggested that the meningioma was an intermediate form between the microcystic and macrocystic types, illustrating the evaluation from the former to the latter.