oculomotor nerve

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Related to CN III: CN IV, CN VI

oculomotor

 [ok″u-lo-mo´tor]
pertaining to or affecting eye movements.
oculomotor nerve the third cranial nerve; it is mixed, that is, it contains both sensory and motor fibers. Various branches of the oculomotor nerve provide for muscle sense and movement in most of the muscles of the eye, for constriction of the pupil, and for accommodation of the eye. See anatomic Table of Nerves in the Appendices.

oculomotor nerve

n.
Either of the third pair of cranial nerves, which originate in the midbrain and control most of the muscles that move the eyeballs.

oculomotor nerve

Etymology: L, oculus + motor, mover
one of a pair of cranial nerves essential for eye movements, supplying certain extrinsic and intrinsic eye muscles. They pass through the superior orbital fissure, connecting to the brain in nucleus III. Also called nervus oculomotorius, third cranial nerve.
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Oculomotor nerve

oculomotor nerve

The third of the paired cranial nerves arising directly from the brainstem. This nerve supplies four of the six small muscles that move the eye, the muscle that elevates the upper lid and the circular muscles of the iris. Paralysis of an oculomotor nerve causes the pupil to be enlarged, the lid to droop and the eye to be unable to turn inwards.

oculomotor nerve

the third cranial nerve of vertebrates, that innervates the muscles which move the eyeball.

nucleus

1. A mass of grey matter composed of nerve cell bodies in any part of the brain or spinal cord and dealing with a common function. 2. Core or central portion of the cell body of a neuron, containing cellular DNA in particular. Plural: nuclei.
abducens nucleus Nucleus of the abducens nerve (sixth cranial nerve) located in the lower part of the pons and whose axons supply the lateral rectus muscle.
accessory oculomotor nucleus See Edinger-Westphal nucleus.
nucleus of the crystalline lens See crystalline lens.
Edinger-Westphal nucleus Part of the oculomotor nucleus, it is situated posterior to the main nucleus and contains the parasympathetic component of the complex. Axons from the Edinger-Westphal pass out along the third (or oculomotor) nerve to synapse in the ciliary ganglion. Postganglionic fibres pass through the short ciliary nerves to the sphincter pupillae and ciliary muscles. The nucleus also receives fibres concerned with accommodation and fibres from the pretectal nucleus dealing with pupil light reflexes. Syn. accessory oculomotor nucleus; accessory parasympathetic nucleus. See pretectal nucleus; pupil light reflex.
lateral nucleus Part of the oculomotor nucleus which supplies, via the oculomotor nerve, all the extraocular muscles except the superior oblique and the lateral rectus muscles.
lateral geniculate nucleus See lateral geniculate body.
oculomotor nucleus This is the nucleus of the oculomotor nerve (third cranial nerve). It is a complex mass of cells located in the midbrain at the level of the superior colliculus and beneath the cerebral aqueduct (of Sylvius) which connects the third and fourth ventricles. It is divided into several subnuclei. See oculomotor nerve; Edinger-Westphal nucleus; Perlia's nucleus; trochlear nucleus.
olivary nucleus See pretectum; pupil light reflex.
Perlia's nucleus Midline part of the oculomotor nucleus. It is rudimentary in man and primates and may provide part of the innervation of the superior rectus muscle.
pretectal nucleus A complex group of nerve cells in the midbrain anterior to the superior colliculi. One of these, the pretectal olivary nucleus, receives retinal inputs via the optic tract and superior brachium and sends axons to both Edinger-Westphal nuclei. It constitutes a centre of the pupil light reflex. Another, the nucleus of the optic tract, may be involved in the control of reflex eye movements. Other fibres from the pretectal nucleus innervate the cornea, the iris, the ciliary muscle and the extraocular muscles (except the lateral rectus and superior oblique muscles), as well as the levator palpebrae muscle.
trochlear nucleus A nucleus of the trochlear nerve (fourth cranial nerve) located at the level of the inferior colliculus and below the posterior end of the oculomotor nerve nucleus, it sends fibres to the contralateral superior oblique muscle.

oculomotor

pertaining to or affecting eye movements.

oculomotor nerve
the third cranial nerve; it contains motor and parasympathetic fibers. Various branches of the oculomotor nerve provide for muscle sense and movement in most of the muscles of the eye, for constriction of the pupil, and for accommodation of the eye. See also Table 14.
oculomotor nerve paralysis
causes pupillary dilatation, absence of pupillary light reflex, ventrolateral deviation of the eye, defective eye movement and palpebral ptosis.
References in periodicals archive ?
We report a new case of pseudo CN III palsy in a very young child with a true orbital ectopic lacrimal gland cyst that was successfully removed via functional endoscopic sinus surgery (FESS).
Her extra-axial tumor produced an unusual clinical appearance of a pseudo CN III palsy.
Midbrain fascicular third cranial nerve palsies Syndrome Signs/characteristics Location of lesion Benedikt Ipsilateral CN III palsy Red nucleus Contralateral extrapyramidal signs Hemitremor/involuntary movements Nothnagel Ipsilateral CN III palsy Fasciculus Superior Cerebellar ataxia cerebellar peduncle Claude Combination of Benedikt and Nothnagel syndromes Weber Ipsilateral CN III palsy Cerebral peduncle Contralateral hemiparesis