Oculomotor nerve

Oculomotor nerve: The oculomotor nerve is responsible for the nerve supply to muscles about the eye: the upper eyelid muscle, the extraocular muscle which moves the eye inward, and the pupillary muscle which constricts the pupil. Paralysis of the oculomotor nerve results in drooping eyelid), deviation of the eyeball outward (and therefore double vision (ptosis) and a dilated (wide) pupil. The oculomotor nerve is the third cranial nerve. There are twelve cranial nerves which emerge from or enter the skull (the cranium) as opposed to the spinal nerves which emerge from the vertebral column.