Meningiomas and their Problems: A Neuropathologist’s Remarks

Abstract

Meningiomas are commonly thought to be derived from a meningothelial (5) matrix, i. e. from the cellular layer covering the arachnoidal membranes and their trabecula. The term of dural endothelioma has become obsolete, all the more so because most textbooks mention a subdural capillary space between the inner surface of the dura and the outer aspect of the pia-arachnoid, and deny the existence of a cellular layer on the inner surface of the dura. Electron-microscopic observations, however, indicate a ‘neurothelial’ cell layer between dura proper and pia-arachnoid (1). These cells appear to be very easily damaged by mechanical tear and autolytic changes. This cell layer can be identified on preparations from human leptomeningeal tissue removed during operation (7). Therefore, the question of histogenetic derivation of meningioma tissue should be re-evaluated.