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Chapter 7
Primary Care Otolaryngology
particular problem, and can help identify the functional dizzy patient.
ECOG
is not really a test of the vestibular system, but is a useful test of
hearing in the evaluation of Ménière’s disease. The test is a variant of
brainstem audio-evoked response and, if possible, should be performed
during active Ménière’s attacks.
Benign Paroxysmal Positional Vertigo
One of the most common causes of vertigo seen by otolaryngologists is
benign paroxysmal positional vertigo (
BPPV)
. This disorder is caused by
sediment, such as
otoconia (calcium carbonate crystals)
that have
become free floating within the inner ear. When the patient turns his or
her head quickly or into a certain position, this free-floating material
moves the balance canal fluid
(endolymph)
in the inner ear and stimu-
lates the vestibular division of the eighth cranial nerve. This motion cre-
ates an intense feeling of vertigo that lasts less than 60 seconds and passes
when the material settles. Patients are usually able to describe the precise
motion that precipitates this intense, brief episode of vertigo. Rolling over
in bed is a movement that frequently initiates an episode and is a fairly
specific symptom. The name of the syndrome comes from the intense, epi-
sodic (paroxysmal) vertigo initiated by certain head positions (positional)
that is not related to a
central nervous system (CNS)
tumor (benign).
This disorder can occur without any specific inciting event, but is often
seen after significant head trauma or an episode of vestibular neuronitis.
BPPV can usually be successfully treated with a canolith reposition
maneuver (Epley or Semont maneuver) in the office setting. Dislodged,
free-floating otoliths repositioned into the vestibule (a portion of the inner
ear) is about 80 percent effective in eliminating symptoms of BPPV. After
a period of time, symptoms may recur, requiring retreatment. Retreatment
is equally effective in relieving symptoms. Medical therapy with vestibular
suppressants is ineffective because the episodes of vertigo are so fleeting,
and should be discouraged. Brandt-Daroff exercises are a home method of
treating BPPV. They can be effective, but may take more time to be effec-
tive.
Surgical treatments , such as transtympanic gentamycin injections, poste-
rior semicircular canal plugging, vestibular nerve sectioning, sacculotomy,
and labyrinthectomy, are some of the surgical options reserved for severe
intractable cases of BPPV. However, they are very rarely employed, as they
can be associated with significant risk of hearing loss and other complica-
tions.