MALIGNANT MENINGIOMA OF THE OCULOMOTOR NERVE WITHOUT DURAL ATTACHMENT- CASE-REPORT AND REVIEW OF THE LITERATURE

Meningiomas, thought to arise from arachnoid cap cells, are usually at tached to the dura. Malignancy is present in approximately 1% of these tumors. The authors report the case of a patient with a malignant men ingioma arising from the oculomotor nerve with no dural attachment. Th e patient presented with a 7-month history of left-sided ptosis and di plopia. Magnetic resonance imaging demonstrated an extrinsic mass comp ressing the root of the oculomotor nerve at its exit from the midbrain . During surgery, a left-sided subtemporal approach revealed the tumor to be arising from the oculomotor nerve. Histological investigation s howed a malignant spindle cell lesion with an immunohistochemical prof ile that was consistent with malignant meningioma. To the authors' kno wledge, this is the first documented case of a malignant meningioma ar ising from the oculomotor nerve.