Bilateral traumatic third nerve palsy.

Bilateral palsy of the third cranial nerve in a head-injured patient is described. Delayed computed tomography scanning demonstrated a midline necrotic lesion within the mesencephalon ventral to the aqueduct. The lesion, possibly the sequela of a focal contusion, involved both third nerve nuclear complexes and caused paralysis of their voluntary as well as autonomic functions. Gaze mechanisms and long tracts appeared to be less heavily damaged. The literature dealing with third nerve palsy, particularly bilateral cases, from traumatic and other origins is briefly reviewed.