Trigeminal Nerve

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trigeminal nerve

[trī′jem·ə·nəl ′nərv]
(neuroscience)
The fifth cranial nerve in vertebrates; either of a pair of composite nerves rising from the side of the medulla, and with three great branches: the ophthalmic, maxillary, and mandibular nerves.

Trigeminal Nerve

 

the fifth pair of cranial nerves. It contains sensory, motor, and autonomic fibers.

The nuclei of the trigeminal nerve are located in the brain stem. The fibers of the trigeminal nerve that constitute the larger, or posterior, root pass from the brain stem to the apex of the temporal bone, where the trigeminal ganglion is located. Three branches depart from the trigeminal ganglion, as follows. The ophthalmic (sensory) nerve leaves the skull through the superior orbital fissure and innervates the upper eyelids, the conjunctiva, the skin of the forehead, and the anterior part of the scalp. The superior maxillary (sensory) nerve leaves the skull through the foramen rotundum, enters the pterygopalatine fossa, and innervates the skin of the lower lid, the cheek and nose, the mucosa of the nasal cavity, and the upper jaw. The inferior maxillary nerve (which is joined to the smaller, or anterior, root of the trigeminal nerve, containing the motor fibers) leaves the skull through the foramen ovale and innervates the skin of the lower part of the face, the mucosa of the cheeks and tongue, the lower jaw, and the muscles of mastication.

The trigeminal nerve takes part in many reflexes, including the corneal and mandibular (jaw) reflex. The most common disease of the trigeminal nerve is neuralgia, manifested by attacks of acute pain in the zone of innervation. Other diseases of the trigeminal nerve, including neuritis and infection with the virus of herpes zoster, are accompanied by sensory and motor disturbances in the zone of innervation.

V. A. KARLOV

References in periodicals archive ?
Most trigeminal schwannomas occur in the Meckel's cave (18), and tend to grow in the parasellar region or extend through the porus trigeminus in the posterior fossa along the cisternal segment of the nerve (15).
Continues its route and it issues about three or four pontine arteries in the pons, and in the emergence of the trigeminus nerve it issues the medium cerebellar artery.
They were located near the soft cerebral membrane, chiefly in the regions of the posterior long fasciculi, the nuclei of the abducent vestibular and trigeminus nerves, under the ependyma, in the area of the cochlear nerve nuclei, the Gover's fasciculi, and in the base of the cerebellum.
1 Oxyrhopus trigeminus Dumeril, Bibron & Dumeril, 1854 3 Philodryas olfersii (Lichtenstein, 1823) 9 Philodryas patagoniensis (Girard, 1858) 7 Philodryas agassizii (Jan, 1863) 1 Pseudoboa nigra (Dumeril, Bibron & Dumeril, 1854) 1 Pseudoboa serrana Morato, Moura-Leite, Prudente & Bernils, 1995 2 Sibynomorphus m.