Signs of Third cranial nerve disorder

Description

The third cranial nerve, also called the oculomotor nerve, is one of three cranial nerves that control the movement of the eye. This nerve controls constriction of the pupil. Damage to this nerve causes the eye to be stuck downward and outward and the pupil will be dilated. The actual symptoms experienced depend on where the damage to the nerve occurs as it travels from the brain to the eye and in some conditions only the eye weakness is experienced. Conditions causing this disorder include congenital oculomotor palsy, diabetes, atherosclerosis, cerebral artery aneurysms, brain tumors, meningitis, traumatic injuries, multiple sclerosis, thiamine deficiency (Wernicke encephalopathy) and cavernous sinus thrombosis.

Symptoms

Double vision, cross eyed or wandering eye, pupil may be abnormally dilated or normal appearing.

Tests

A history and physical exam will be performed to make the diagnosis. Brain imaging is usually required to confirm the diagnosis.

Standard Workup

CBC
Chem 12
CT Scan
MRI

Treatment

Treatment depends on the cause. Emergency treatment is required if a life-threatening disorder is the cause. If caused by thiamine deficiency, it may respond to thiamine.