Neurilemmoma of the oculomotor nerve presenting as an orbital mass: MR findings.

Neurilemmoma of the oculomotor nerve is rare and infrequently presents as an orbital mass. We report a neurilemmoma arising from the cavernous sinus with its major part extending into the orbit. The Antoni A part of the neurilemmoma showed intermediate signal intensity in both T1- and T2-weighted MR images and exhibited postcontrast enhancement. The Antoni B part revealed hypointensity on T1-weighted images, hyperintensity in T2-weighted images, and showed no contrast enhancement.