facial nerve


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Related to facial nerve: Cranial nerves, glossopharyngeal nerve, trigeminal nerve, vagus nerve, vestibulocochlear nerve

facial

 [fa´shal]
pertaining to or directed toward the face.
facial nerve the seventh cranial nerve; its motor fibers supply the muscles of facial expression, a complex group of cutaneous muscles that move the eyebrows, skin of the forehead, corners of the mouth, and other parts of the face concerned with frowning, smiling, or any of the many other expressions of emotion. The sensory fibers of the facial nerve provide a sense of taste in the anterior two thirds of the tongue, and also supply the submaxillary, sublingual, and lacrimal glands for secretion. Irritation of the facial nerve can produce a paralysis known as bell's palsy, which usually involves only one side of the face with a resulting distortion of facial expression such as inability to close the eye or part of the mouth on the affected side. See anatomic Table of Nerves in the Appendices.

facial nerve

n.
Either of the seventh pair of cranial nerves that control facial muscles and relay sensation from the taste buds of the front part of the tongue.

facial nerve

either of a pair of mixed sensory and motor cranial nerves that arise from the brainstem at the base of the pons and divide immediately in front of the ear into six branches, innervating the scalp, forehead, eyelids, muscles of facial expression, cheeks, and jaw. Also called seventh cranial nerve.
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facial nerve
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SUPERFICIAL BRANCHES OF FACIAL NERVE (7TH CRANIAL))

facial nerve

A mixed nerve consisting of efferent fibers supplying the facial muscles, the platysma muscle, the submandibular and sublingual glands; and of afferent fibers from taste buds of the anterior two thirds of the tongue and from the muscles.

Sensory

Taste fibers from the anterior two thirds of the tongue and the soft palate follow the chorda tympani to their neuronal cell bodies in the geniculate ganglion; the axons of these neurons follow the nervus intermedius (the sensory root of the facial nerve) into the pons where they synapse in the nucleus of the tractus solitarius (the gustatory nucleus).

Motor

Somatic motor axons from the motor nucleus of the facial nerve in the pons emerge as the motor root of the facial nerve and enter the bone of the skull through the internal auditory meatus. The motor axons follow the facial canal inside the temporal bone and exit the skull through the stylomastoid foramen. From there, the axons innervate all the muscles of facial expression. Preganglionic parasympathetic axons from the superior salivatory nucleus take the nervus intermedius to the region of the geniculate ganglion inside the facial canal. From there, some of the axons join the chorda tympani and later reach the submandibular ganglion by following the lingual nerve. Other preganglionic parasympathetic axons follow the major superficial petrosal nerve and the vidian nerve to reach the pterygopalatine ganglion.

Synonym: seventh cranial nerve See: illustration; cranial nerve
See also: nerve

facial nerve

One of the 7th of the 12 pairs of CRANIAL NERVES. Each facial nerve supplies the muscles of the face on its own side. Loss of function in a facial nerve causes partial or total paralysis of one side of the face. This is called BELL'S PALSY.

facial nerve

the 7th cranial nerve, a dorsal root that in mammals is mainly motor in function, supplying facial muscles, the salivary glands and the front-of-tongue taste buds.

facial nerve,

facial

of or pertaining to the face.

facial abscess
see malar abscess.
facial cleft
very uncommon congenital defect of failure of closure at various facial sites, e.g. cleft from corner of mouth to ear on the same side.
facial dermatitis
see contagious porcine pyoderma.
facial eczema
hepatogenous photosensitization in sheep and cattle, by the ingestion of sporidesmin from the the fungus Pithomyces chartarum. It grows best on litter in pasture composed of plants with heavy leaf growth, e.g. perennial rye and white clover. Many animals die early because of the hepatic insufficiency combined with the widespread tissue damage.
facial fold dermatitis
see fold dermatitis.
facial hyperostosis
idiopathic facial dermatosis of Persian cats
inflammation of the periocular, perioral skin and sometimes chin associated with the accumulation of black material matting the skin. External ear canals may also become involved. The cause is unknown.
facial nerve
the seventh cranial nerve; its motor fibers supply the muscles of facial expression. These are a complex group of cutaneous muscles that move the eyebrows, eyelids, ears, corners of the mouth, and other parts of the face. The sensory fibers of the facial nerve provide a sense of taste in the forward two-thirds of the tongue, and also supply the submaxillary, sublingual and lacrimal glands for secretion. See also Table 14.
facial nerve root granuloma
chronic, inflammatory disease in calves characterized by space-occupying, granulomatous lesions on the facial and vestibulocochlear nerves and clinical signs of facial paralysis and balance abnormalities.
facial paralysis
characterized by unilateral signs related to facial movements and asymmetry of the face. There is droopiness of the ear and an inability to move it, drooping of the eyelid, sagging and drooping of the lower lip and deviation of the nose to the normal side.
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Facial paralysis in a horse. By permission from Knottenbelt DC, Pascoe RR, Diseases and Disorders of the Horse, Saunders, 2003
facial sinus
see malar abscess.
facial sinusitis
infection and inflammation occurs secondarily to rhinitis or to damage to a horn or dehorning. Neoplasia of a horn core may extend into the sinus.
facial tumor disease
see tasmanian devil facial tumor disease.
References in periodicals archive ?
Although a blink reflex study was not initially performed on this particular patient, the results of such a test would yield objective evidence of the physiological status of the facial nerve.
Apart from this, infections in the brain or in the parotid glands ( key pathways for the facial nerve, located in the upper part of each cheek) can also lead to facial paralysis.
Accelerating functional recovery after rat facial nerve injury: Effects of gonadal steroids and electrical stimulation.
Facial nerve palsy, swallowing problems and hoarseness may occur if cranial nerves are involved.
8) While MRI is only indicated for facial nerve lesions of the brainstem, cerebellopontine angle, and intratemporal locations, EMG may aid in clinical decision making for superficial facial nerve lesions.
If the facial nerve palsy is not treated with steroids, the likelihood of permanent facial paralysis is increased.
Matthew Kircher of Loyola University Medical Center is giving patients Botox injections to treat facial nerve disorders that sometimes occur after Bell's palsy, including unwanted facial movements known as synkinesis.
scared i'd had a stroke I went to a&e, where I was diagnosed with Bell's palsy, facial paralysis caused by damage to the facial nerve - probably a result of exposure to the cold before it had fully healed.
It is the most common form of facial paralysis that occurs when the facial nerve becomes damaged or inflamed.
Prior to the administration of reversal, the train-of-four response to facial nerve stimulation of the orbicularis oculi muscle was assessed.
As a result of the unprovoked attack, Wyatt suffered disfigurement and a partial facial paralysis from a severed facial nerve.
Indeed, local physicians and surgeons may be too willing to refer patients with these tumors to tertiary hospitals either because of their relative infrequency, concern about the lack of expertise required to treat them, or to avoid the potential for catastrophic facial nerve paralysis or complication.