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Oculomotor nerve


pl. oculomotor nerves

1. The 3rd of 12 paired cranial nerves. It enters the orbit via the superior orbital fissure and controls most of the eye’s movements, including constriction of the pupil and maintaining an open eyelid by innervating the levator palpebrae superioris muscle. The oculomotor nerve is derived from the basal plate of the embryonic midbrain. Cranial nerves IV and VI also participate in control of eye movement. (wikipedia.org)

2. Either nerve of the third pair of cranial nerves that are motor nerves with some associated autonomic fibers, arise from the midbrain, supply muscles of the eye except the superior oblique and the lateral rectus with motor fibers, and supply the ciliary body and iris with autonomic fibers by way of the ciliary ganglion. (merriam-webster.com)

3. The occulomotor nerve is responsible for motor enervation of upper eyelid muscle, extraocular muscle and pupillary muscle. Lesions of the oculomotor nerve results in ptosis (dropping eyelid), deviation of the eyeball outward, double vision and a dilated pupil. (biology-online.org)

Syn: nervus oculomotorius, third cranial nerve,


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