[Neurinoma of the oculomotor nerve (author's transl)].

Three cases of histologically verified neurinomas of the oculomotor nerve are reported. The preoperative diagnosis in all three cases was not made; on the contrary all cases were diagnosed as sphenoid ridge meningiomas. The oculomotor neurinoma manifests itself in the beginning with a discrete progressive palsy of the oculomotor nerve leading in later stages to complete ophthalmoplegia. Proceeding the oculomotor nerve paresis or going parallel to it is a functional loss of the homolateral optic nerve sometimes progressing to amaurosis. Unilateral exophthalmos as well as frontal or orbital neuralgic pain with or without sensory disorders in the area of trigeminus-I are characteristic for the clinical picture in later stages, all symptoms characteristic for the syndrome of the apex orbitae, resp. the superior orbital fissure, resp. the anterior cavernous sinus. The differential diagnosis has to consider above all the sphenoid ridge meningioma, the trigeminal neurinoma and the numerous tumors within the cavernous sinus (aneurysmas, meningiomas, chondromas, metastases of carcinomas, pituitary adenomas etc.) or the middle cranial fossa. Plain X-ray, carotid angiogram and computer tomogram are essential diagnostic means for localization and extension of the tumor but not for histological diagnosis. Oculomotor neurinomas are very seldom. The three observed cases did not have any relation to a possible generalized neurofibromatosis.