[The dura mater adjacent to the attachment of meningiomas: its enhanced MR imaging and histological findings].

The dura mater adjacent to the attachment of meningiomas was enhanced on MR imaging with intravenous Gd-DTPA infusion. It was examined histologically in four patients with intracranial globoid meningiomas. Histological examination revealed that there was no tumor cell invasion within the dura mater enhanced on MR imaging, except at the point of their attachment. A layer of tumor cells was occasionally observed on the surface of the dura mater, but this was limited to within 5 mm of the tumor margin. Our electronmicroscopic observation indicated that enhancement of the dura mater adjacent to the attachment of meningiomas was caused by increased vascular permeability of the dural vessels and extended extravascular space.