Common causes of peripheral facial paralysis: (1) Infectious lesions: herpes zoster of the ear, meningitis, mumps, scarlet fever, multiple cranial neuritis, localized infections. (2) ear-derived diseases: such as otitis media, labyrinthitis, mastoiditis, purulent inflammation of the temporal bone. (3) Tumors: basilar artery aneurysm, skull base tumor, acoustic neuroma, jugular vein bulb tumor. Zhang Changming, Department of Otorhinolaryngology, Xijing Hospital (4) Trauma: skull base fracture, facial trauma. (5) Poisoning: such as alcohol poisoning. (6) Metabolic disorders: such as diabetes, vitamin deficiency. (7) Vascular insufficiency. (8) Congenital hypoplasia of the facial nerve nucleus. Peripheral facial paralysis, also known as facial neuritis (Bell’s palsy), commonly known as crooked mouth disease, is an acute suppurative inflammation of the facial nerve in the facial nerve canal above the mastoid foramen of the stem, which is more common in cerebral neurological disorders. First, the etiology and pathogenesis of the facial neural tube is a narrow bony tube, the facial nerve in the role of external factors, it is easy to damage, but the detailed etiology of this disease has not yet been clarified, clinically most of the head and face due to the cold caused by the second speculation may be related to local vascular disease, viral infections, and it has also been proposed that patients with diabetes mellitus, hypertension may be a higher incidence of normal population. The pathological changes are facial nerve edema, demyelination, and in severe cases, axonal degeneration, which is often irreversible. Clinical manifestations can be seen at any age, but are most common between 20 and 40 years of age, and are more common in males than in females. The disease can develop at any time of the year, and is more common in summer and winter. Acute onset, mostly unilateral, peak in a few hours, some patients feel pain and discomfort around the ear on the affected side a few days before the onset of the disease, and individual herpes (Hunt’s syndrome), most of the patients found that both sides of the face are asymmetrical in the morning when they washed their face, and one side of the facial muscles do not work well, and the affected side of the eye fissure is large, the corners of the mouth are drooping, drooling, and when eating, they feel that the food is retained in the affected side in the gap between the cheek and the teeth, and so on. C. Special examination Cranial CT and MRI can exclude brainstem (pontine) lesions; electromyography shows that the latency M wave amplitude of the affected side of the facial nerve is reduced or disappeared. The white blood cells in the peripheral blood may be high in those caused by infection. Differential diagnosis: Acute infectious polyradiculoneuritis: facial paralysis is often bilateral, and most of them are accompanied by symmetrical paralysis of other cranial nerves and limbs, and cerebrospinal fluid examination shows protein-cell separation phenomenon. Brainstem lesions (pontine damage): peripheral facial paralysis can occur, but often accompanied by damage to neighboring structures within the pontine brain, manifested by inability to abduct the eyeballs, facial sensory abnormalities, as well as tinnitus, deafness, ipsilateral limb ataxia and contralateral limb paralysis of varying degrees and other symptoms. The above symptoms are mostly caused by tumor, inflammation and vascular disease. 3, Facial nerve adjacent structure lesion: common otitis media, parotitis, purulent mandibular lymphadenitis can also invade the facial nerve. 4, traumatic facial nerve injury: there may be obvious history of head and face trauma, which is easier to distinguish. V. Disease course and prognosis After timely and regular treatment, the general prognosis is good, the recovery will start in one to two weeks, and the disease will be cured in one to two months, and about 80% to 90% of the patients can be fully recovered without sequelae. About 80% to 90% of the patients can recover completely without sequelae. However, those who cannot recover completely within half a year have a poorer prognosis and may have permanent sequelae, and some of them may have facial muscle spasms. At present, electromyography detects the wave amplitude of M wave of action nerve to predict the prognosis. Prevention and treatment Daily attention to enhance physical fitness, pay attention to facial warmth in the cold season, avoid sitting or sleeping in the head and face wind, and timely treatment of colds. The principle of treatment is to relieve the pressure and edema of facial nerve as soon as possible, and enhance the nutrition and blood supply of facial nerve. 1, physical therapy: within two weeks after the disease, we should actively take ultrashort wave or iodine iontophoresis treatment near the affected side of the stems and breasts, in order to improve the circulation and eliminate edema. 2.Body therapy: patients do frowning, closing eyes, showing teeth, puffing cheeks and whistling in the mirror, and massage the paralyzed facial muscles with hands several times a day for 5-10 minutes each time. 3, drug therapy: ① corticosteroids; ② neurotrophic drugs; ③ drugs to improve circulation; ④ such as Hunt’s syndrome: acyclovir or ganciclovir in appropriate amount, used for 10 to 15 days; ⑤ surgical therapy: early decompression of the facial nerve; patients who can not be restored in the late stage of the feasibility of the facial nerve – phrenic nerve or facial nerve – parasympathetic anastomosis, the efficacy of which is not yet known. Surgery: early decompression of the facial nerve; patients who cannot recover in the late stage can have facial nerve-phrenic nerve or facial nerve-parasympathetic nerve anastomosis. Hunt syndrome: Hunt syndrome is a group of multiple cranial neuritis diseases caused by varicella-zoster virus infection. The incidence of the disease is gradually increasing. It is more common in the elderly and other people with decreased body resistance. The facial nerve is most likely to be involved. Typical clinical manifestations are: severe pain in one ear, usually 2-7 days later, the skin of the auricle, ear canal, and postauricular sulcus appear to disseminate small herpes, and paralysis of the same side progresses rapidly and reaches its peak within 7 days. The auditory nerve is the second nerve that is easily affected, manifesting as vertigo, facial paralysis, ipsilateral tinnitus and sudden loss of hearing, which may be accompanied by vomiting and a feeling of unsteadiness in walking. In addition, involvement of the glossopharyngeal nerve presents with sore throat, ipsilateral soft palate, herpes on the back of the tongue, and, rarely, hypermobility of the soft palate. Encephalitis symptoms, clinicians should pay great attention to this disease. The prognosis of facial paralysis in patients with Hunt’s syndrome is worse than Bell’s palsy, requiring early treatment with large amounts of hormones and antiviral drugs, and early surgical decompression for those with a poor prognosis on electrophysiologic examination.