Optic nerve sheath meningioma. Definition of intraorbital, intracanalicular, and intracranial components with magnetic resonance imaging.

Magnetic resonance imaging with fat saturation after the administration of gadolinium-DTPA can detect and demarcate meningioma of the optic nerve sheath with a precision not attainable with any other current imaging technique. This article describes some of the clinical implications of this technique and illustrates the appearance of this tumor on magnetic resonance images.