Pupil-sparing oculomotor nerve palsy due to midbrain infarction.

Vasculopathic oculomotor nerve palsies with pupillary sparing are thought to be due to ischemic damage to the nerve in the subarachnoid space or the cavernous sinus. We present two cases of patients with isolated pupil-sparing oculomotor nerve palsies due to midbrain infarcts. Focal ischemic midbrain lesions should be considered in cases of pupil-sparing oculomotor nerve palsies.