1.12 Bell's Palsy (Idiopathic Facial Paralysis)
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agk's Library of Common Simple Emergencies

Presentation
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This condition creates a very frightening 
facial disfigurement. An adult complains of 
sudden onset of "numbness," a feeling of 
fullness or swelling, pain or some other change 
in sensation on one side of the face; a crooked 
smile, mouth "drawing" or some other asymmet- 
rical weakness of facial muscles; an irritated, 
dry or tearing eye; drooling out of the corner 
of the mouth; or changes in hearing or taste. 
Often there will have been a viral illness one 
to three weeks before. Upon initial observation 
of the patient, it is immediately apparent that 
he is alert and oriented, with a unilateral 
facial paralysis that includes one side of the 
forehead.

What to do:
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- Perform a thorough neurological examination 
   of cranial and upper cervical nerves, and 
   limb strength, noting which are involved, 
   and whether unilaterally or bilaterally. Ask 
   the patient to wrinkle the forehead, close 
   the eyes forcefully, smile, puff the cheeks 
   and whistle, observing closely for facial 
   assymetry. Central or cerebral lesions 
   result in relative sparing of the forehead. 
   Check tearing, ability to close the eye and 
   protect the cornea, corneal dessication, 
   hearing, and, when practical, taste. Examine 
   the ear canals for herpetic vesicles and the 
   tympanic membrane for signs of otitis media 
   or cholesteatoma. Patients presenting with 
   facial paralysis accompanied by acute otitis 
   media, chronic suppurative middle ear 
   disease, otorrhea or otitis externa require 
   otolaryngologic consultation.
- If the cornea is dry or injured from the 
   patient's inability to make tears and blink, 
   protect it by patching. If patching is not 
   necessary, then recommend wearing eyeglasses 
   and applying methylcellulose artificial 
   tears regularly during the day and using a 
   protective bland ointment at night.
- If there is a history of head trauma, obtain 
   a CT scan of the head (including the skull 
   base) to rule out a temporal bone fracture.
- If the diagnosis is clearly an early 
   idiopathic cranial nerve palsy not caused or 
   complicated by trauma, infection, or 
   diabetes, try to ameliorate symptons with a 
   short course of corticosteroids (e.g., 
   prednisone 60mg qd, tapering after 5 days.)
- Send a serum specimen for acute phase Lyme 
   disease titers, if available, because this 
   is another treatable disorder which can 
   present as a facial neuropathy. In areas 
   where Lyme disease is endemic, a 10 day 
   course of tetracycline or doxycycline may be 
   indicated.
- If the etiology appears to be zoster- 
   varicella (e.g., grouped vesicles on the 
   tongue) prescribe acyclovir or famcyclovir 
   as for shingles.
- Reassure the patient that 70-80% of cases of 
   Bell's palsy recover completely in a few 
   weeks, but provide for definite followup and 
   reevaluation.
- Provide appropriate specialty referral when 
   there is a mass in the head or neck or a 
   history of any malignancy.

What not to do:
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- Do not forget alternate causes of facial 
   palsy which require different treatment, 
   such as cerebrovascular accidents and 
   cerebellopontine angle tumors (which usually 
   produce weakness in limbs or defects of 
   adjacent cranial nerves), multiple sclerosis 
   (which is usually not painful, spares taste, 
   and often produces intranuclear ophthalmo- 
   plegia), Ramsay Hunt syndrome (or herpes 
   zoster of the geniculate ganglion, which 
   causes decreased hearing, pain, and vesicles 
   in the ear canal), and polio (which presents 
   as fever, headache, neck stiffness, and 
   palsies).
- Do not order a CT unless there is a history 
   of trauma or the symptoms are atypical and 
   include such findings as vertigo. central 
   neurological signs, or severe headache.
- Do not make the diagnosis of Bell's palsy in 
   patients who report gradual onset of facial 
   paralysis over several weeks or facial 
   paralysis that has persisted 3 months or 
   more. These patients need further evaluation 
   by a neurologist or otolaryngologist.

Discussion
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Idiopathic nerve paralysis is a common malady. 
It affects 20 per 100,000 people a year. 
Although Bell's palsy was described classically 
as a pure facial nerve lesion, and physicians 
have tried to identify the exact level at which 
the nerve is compressed, the most common 
presenting complaints are related to trigeminal 
nerve involvement. The mechanism is probably a 
spotty demyelination of several nerves at 
several sites, caused by a viral infection. 
Diabetics and pregnant women have increased 
incidence of Bell's palsy.

References:
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- Austin JR, Peskind SP, Austin SG, et al: 
   Idiopathic facial nerve paralysis: a 
   randomized double blind controlled study of 
   placebo versus prednisone. *Laryngoscope* 
   1993;103:1326-1333.
- Stankiewicz JA: A review of the published 
   data on steroids and idiopathic facial 
   paralysis. *Otolaryngol Head Neck Surg* 
   1987;97:481-486.

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