Bell palsy


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Bell pal·sy

paresis or paralysis, usually unilateral, of the facial muscles, caused by dysfunction of the seventh cranial nerve; probably due to a viral infection; usually demyelinating in type.

Bell pal·sy

(bel pawl'zē)
Paresis or paralysis, usually unilateral, of the facial muscles, caused by dysfunction of the seventh cranial nerve; probably due to a viral infection; usually demyelinating in type.
Synonym(s): peripheral facial paralysis.
Enlarge picture
BELL PALSY: Asymmetrical smile in patient with Bell Palsy

Bell palsy

Paralysis of the facial nerve. Bell palsy is usually caused by a reactivation of herpes simplex virus although other infections (such as syphilis or Lyme disease) are sometimes implicated. Complications may include corneal drying and ulceration and mild dysarthria. Either side of the face may be affected. Attacks recur in about 10% of cases. Synonym: Bell paralysisfacial palsy; facial nerve palsy; facial nerve paralysis; facial paralysis

Symptoms

Paralysis of the facial nerve typically results in an asymmetrical facial appearance. The affected patient is unable to raise one side of the mouth to smile or to wrinkle or raise the eyebrow on the same side. This peripheral nerve dysfunction is distinguished from strokes that alter facial movement by the involvement of both the forehead and the mouth. Paralysis of the face caused by strokes usually only limits movement of the oral muscles. See: illustration

Treatment

Tapering doses of prednisone without antiviral drugs provide the most effective results. In addition, the affected eye should be protected from drying with artificial tears or unmedicated ointments. Some practitioners advise wearing sunglasses during the palsy or patching the eye to protect it from foreign bodies or drying.

Prognosis

Partial facial paralysis is usually resolved within several months. The likelihood of complete recovery after total paralysis varies from 20% to 90%.

Bell,

Sir Charles, Scottish surgeon, anatomist, and physiologist, 1774-1842.
Bell law - the ventral spinal roots are motor, the dorsal are sensory. Synonym(s): Bell-Magendie law; Magendie law
Bell-Magendie law - Synonym(s): Bell law
Bell palsy - paresis or paralysis, usually unilateral, of the facial muscles, caused by dysfunction of the 7th cranial nerve. Synonym(s): peripheral facial paralysis
Bell phenomenon - upward movement of the eye on attempted eyelid closure in a patient with peripheral facial paralysis.
Bell respiratory nerve - Synonym(s): long thoracic nerve
Bell spasm - involuntary twitching of the facial muscles. Synonym(s): facial tic
external respiratory nerve of Bell - Synonym(s): long thoracic nerve

Bell pal·sy

(bel pawl'zē)
Paresis or paralysis, usually unilateral, of the facial muscles, caused by dysfunction of the facial nerve.
References in periodicals archive ?
Although Bell palsy remains the most common cause of peripheral facial nerve paralysis, patients in whom neoplasms invade the facial nerve may present with acute paralysis mimicking Bell palsy that fails to resolve.
Although Bell palsy has been defined as idiopathic, there is now good evidence to implicate the activation of herpes simplex virus near the geniculate ganglion as the cause of this disorder.
Eleven of these 320 cases met the criteria of the study--namely, presentation with facial paralysis mimicking Bell palsy that was found to be caused by an occult malignancy, The records of these patients were retrospectively reviewed.
After a diagnosis of Bell palsy was reached, he had been referred to us for treatment.
He had apparently been told he had a right-sided Bell palsy.
Bell palsy remains a diagnosis of exclusion and is best made after a thorough otolaryngological examination demonstrates no evidence of occult malignancy.
Most patients with Bell palsy do not experience pain, and some facial nerve recovery, usually within 6 weeks to 3 months, is observed in all.
Table 1 Differential diagnosis of facial nerve paralysis Infectious Bell Palsy Herpes zoster oticus Acute otitis media Mastoiditis Necrotizing external otitis Skull base osteomyelitis Lyme disease Other Traumatic Basilar skull fracture Birth injury Penetrating temporal bone trauma Parotid injury tatrogeic Neoplastic Facial nerve neuroma Facial nerve hemangioma Carcinoma (primary or metastatic and intra- or extratemporal) Jugular glomus Vestibular schwannoma Meningioma Metastatic lesion Inflammatory Cholesteatoma Sarcoidosis Wegener granulomatosis Other Congenital Table 2 Presenting symptoms and signs Symptom/sign No.
MR imaging of facial nerve enhancement in Bell palsy or after temporal bone surgery.