[Meningioma of the optic nerve sheath. Diagnostic problems despite use of modern imaging procedures].

In spite of modern optical examination techniques such as sonography, nuclear magnetic resonance tomography (NMR) and x-ray computer tomography up to now the meningioma of the optic nerve sheath still poses a problem in respect of differential diagnosis. This problem is illustrated by two case reports. In both patients a meningioma of the optic nerve sheath could be diagnosed only after various attempts using all the imaging techniques mentioned above. NMR in combination with Gadolinium injection gave most important information.