Primary Care Otolaryngology

Chapter 7

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.

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Primary Care Otolaryngology