- What is the most common cause of lower motor neuron facial nerve paralysis?
How does it present?
The most common cause is Bell palsy. Look for sudden unilateral onset, usually after an upper
respiratory infection. The cause is thought to be a reactivation of latent herpes simplex I
infection in most cases. Patients may have hyperacusis, in which everything sounds loud
because the stapedius muscle in the ear is paralyzed. In severe cases, patients may be
unable to close the affected eye; if so, use drops to protect the eye. Most cases resolve
spontaneously in about 1 month, although some have permanent sequelae. Oral prednisone
and antiviral treatment for herpes (e.g., valacyclovir, acyclovir) may improve outcome and
lessen duration of symptoms. - What are the other causes of lower motor neuron facial nerve paralysis?
n Herpes infection (Ramsay Hunt syndrome), which commonly involves the eighth
nerve. Look for vesicles on the pinna and inside the ear; encephalitis or meningitis may
be present.
n Lyme disease (one of the most common causes of bilateral facial nerve palsy)
n Stroke
n Middle ear or mastoid infections
n Meningitis
n Temporal bone fracture (look for Battle sign and/or bleeding from the ear)
n Tumor, classically an acoustic schwannoma (i.e. neuroma) of the cerebellopontine angle
(Fig. 8-1)
Order a computed tomography (CT) or magnetic resonance (MR) scan of the head if the
cause is not apparent or if the history or physical exam raises suspicion—especially in the
presence of additional neurologic signs. - What are the common causes of hearing loss?
The most common cause is aging (presbyacusis); prescribe a hearing aid, if needed.
The history may suggest other causes:
n Prolonged or intense exposure to loud noise (e.g., work-related)
n Congenital TORCH infection (toxoplasmosis, others, rubella, cytomegalovirus, herpes virus)
n Me´nie`re disease (accompanied by severe vertigo, tinnitus, nausea and vomiting; treat
with anticholinergics and antihistamines [meclizine]; surgery may be used for refractory
cases)
n Drugs (e.g., aminoglycosides, aspirin, quinine, loop diuretics, cisplatin)
n Tumor (classically acoustic neuroma)
n Labyrinthitis (may be viral or follow or extend from meningitis or otitis media)
n Miscellaneous causes (diabetes, hypothyroidism, multiple sclerosis, sarcoidosis,
pseudotumor cerebri). - What is the usual cause of sudden deafness?
Sudden deafness (developing over a few hours) most often is due to a viral cause
(endolymphatic labyrinthitis from mumps, measles, influenza, chickenpox, or adenovirus).
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Hearing usually returns within 2 weeks, but the loss may be permanent. No treatment has
proved effective, but empirical steroids often are used. Trauma with temporal bone fracture is
another cause of sudden hearing loss. Treatment is supportive. - What is the most common cause of acquired hearing loss in children?
Bacterial meningitis. All children should receive formal hearing testing after a bout of
meningitis. - What are the common causes of vertigo?
Vertigo can result from the same eighth cranial nerve lesions that cause hearing loss (Meniere
disease, tumor, infection, multiple sclerosis). Another common cause is benign positional
(paroxysmal) vertigo, which is induced by certain head positions, may be accompanied by
nystagmus, and is not associated with hearing loss. This condition often resolves
spontaneously; no treatment is required. - How is a deviated nasal septum treated in patients with recurrent sinusitis?
Surgical correction. - What are the three common causes of rhinitis?
Viral, allergic, and bacterial. - How do you recognize and treat viral rhinitis?
Viral rhinitis (the common cold) may be due to rhinovirus (the most common cause),
influenza, parainfluenza, coxsackie virus, adenovirus, respiratory syncytial virus, coronavirus,
or echovirus. Treatment is symptomatic. Vasoconstrictors such as phenylephrine can be used
for short-term symptomatic relief, but they may cause rebound congestion when discontinued. - How do you recognize and treat allergic rhinitis?
Allergic rhinitis (hay fever) is associated with seasonal flare-ups, boggy and bluish turbinates,
onset before 20 years of age, nasal polyps, sneezing, pruritus, conjunctivitis, wheezing or
asthma, eczema, positive family history, eosinophils in nasal mucous, and elevated serum IgE.
Skin tests may identify an allergen. Treat with avoidance of known antigens (e.g., pollen).
Antihistamines, cromolyn, and/or nasal steroids may be used for more severe symptoms.
Desensitization also is an option