Facts on File Encyclopedia of Health and Medicine

they were legitimate, instructing the body to react
to movement that is not occurring or failing to
direct reaction when there is movement. This con-
fusion results in vertigo and a sense of spatial dis-
orientation. Vestibular neuronitis most commonly
occurs in adults between the ages of 40 and 60.

Symptoms and Diagnostic Path

The distinguishing symptoms of vestibular neu-
ronitis are severe vertigo and one-sided balance
disturbances without TINNITUSor HEARING LOSS. Any
hearing-related symptoms suggest a different diag-
nosis. The vertigo causes nausea and often vomit-
ing. Attempts to move, or to move the head, result
in repeated vertigo. The symptoms often are debil-
itating, with the person falling toward the affected
side when attempting to walk and sometimes
when attempting to sit upright. Symptoms appear
abruptly though often follow a cold or occur
among groups of people who are in close contact.
An initial episode of symptoms can last 7 to 10
days.
The diagnostic path is fairly straightforward;
any pattern of vestibular disturbance that includes
additional symptoms is likely to have a different
cause. Confirming diagnostic signs the doctor
looks for include

• horizontal NYSTAGMUS(rapid movements of the
  EYEwith certain positions or movements)


• diminished or absent response to caloric testing
  (alternating warm and cool water infused into
  the auditory canal)

Imaging procedures are not likely to offer diag-
nostic information unless the doctor is uncertain
of the diagnosis, in which case MAGNETIC RESONANCE
IMAGING(MRI) or COMPUTED TOMOGRAPHY(CT) SCAN
can rule out other conditions such as ACOUSTIC
NEUROMA.

Treatment Options and Outlook

The VIRUScausing the vestibular neuronitis must
run its course, which typically takes 10 to 14 days.
During this time, certain ANTIHISTAMINE MEDICATIONS
used to treat motion sickness can provide relief
from the vertigo and associated nausea. These
antihistamines include the prescription medica-
tions hydroxyzine (Atarax, Vistaril) and prome-

thazine (Phenergan) and the over-the-counter

products dimenhydrinate (Dramamine), meclizine

(Antivert, Bonine) and diphenhydramine

(Benadryl). The two prescription medications

diazepam (Valium) and clonazepam (Klonopin)

appear to act on the vestibular system directly to

subdue the vertigo, though cause more sedation

than antihistamines and can be addictive when

used for an extended period of time. ACUPUNCTURE

gives some people relief. Most people recover

completely and are free from residual conse-

quences in three to four weeks. A small percent-

age experiences recurrent episodes over the

following months to years, though the severity of

symptoms diminishes with each episode.

Risk Factors and Preventive Measures

Because doctors do not know for certain what

causes vestibular neuronitis, they cannot identify

risk factors or preventive measures. Prompt diagno-

sis and treatment help relieve symptoms more

quickly but do not appear to alter the course of the

inflammation or affect the likelihood of RECURRENCE.

See also CRANIAL NERVES; BENIGN PAROXYSMAL POSI-

TIONAL VERTIGO(BPPV); LABYRINTHITIS; MÉNIÈRE’S DIS-

EASE.

vocal cord cyst A saclike growth on the vocal

cord that usually develops as a result of persistent

irritation such as from smoking or GASTROE-

SOPHAGEAL REFLUX DISORDER (GERD), which may

flush the VOCAL CORDSwith gastric juices when an

individual is lying down and especially when he

or she is sleeping. A vocal cord cyst often contains

fluid though can contain solid tissue. A cyst can

develop deep within the vocal folds, causing sig-

nificant changes or difficulties with the voice. The

primary symptom of vocal cord cyst is hoarseness.

Though vocal cord cysts are noncancerous, oto-

laryngologists generally operate to remove them

because they tend to enlarge. Endoscopic surgery

allows the otolaryngologist to remove most vocal

cord cysts through the THROAT. Recovery from the

surgery takes two to four weeks; most people ben-

efit from follow-up VOICE THERAPYto teach meth-

ods for preserving vocal cord integrity and voice

quality.

See also OPERATION; SMOKING AND HEALTH;VOCAL

CORD NODULE; VOCAL CORD POLYP.

62 The Ear, Nose, Mouth and Throat