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