Relative pupil-sparing oculomotor nerve palsy as the presenting sign of posterior fossa meningioma

We report a case of relative pupil-sparing oculomotor paresis initially att ributed to ischemia because weakness of other cranial nerves was minimal an d dismissed as insignificant. Neuroimaging eventually revealed a posterior fossa meningioma. The neurologic symptoms and signs disappeared immediately after resection of the tumor. The third nerve palsy was attributed to defo rmation of the brainstem. This case reinforces the importance of neuroimagi ng even in patients who have apparently isolated oculomotor palsy with feat ures not classic for an ischemic etiology.