Vertigo
Vertigo – (Dizziness)
Classifications:
- Benign positional vertigo. Each episode lasts seconds to minutes.
- Menière’s disease. Each episode lasts hours to days.
- Toxic damage to labyrinth (e.g., salicylates, ETOH [alcohol]). Variable depending on etiology.
- Labyrinthitis (e.g., viral). Each episode of vertigo lasts days.
Causes of recurrent episodes of vertigo. Benign paroxysmal positional vertigo (BPPV). Most common cause of recurrent vertigo. Historical characteristics: change in head position precipitates brief episodes of vertigo; not associated with tinnitus; may be associated with nausea but rarely emesis. Follows a waxing and waning course over months to years, but most cases resolve with time. Most common age of onset is between 60 and 70. Women with BPPV outnumber men by 2:1.
This condition is caused by calcium carbonate crystals displaced within the posterior semicircular canal. Confirm by the Dix-Hallpike test, which is performed by rapidly laying down the patient from sitting position, allowing the head to hang over the edge of the bed while simultaneously turning the head to the left or right. A positive test manifests as vertigo and the observation of rotatory nystagmus within 30 seconds of the maneuver. With the diagnosis confirmed, a positioning procedure can be performed that relocates the offending crystal.
Literature cites success rates in excess of 85% for patients treated in this manner. For refractory cases, brief therapy with benzodiazepines (e.g., diazepam 2 to 5 mg or vestibular rehabilitation exercises may be of use. Meclizine (Antivert) is an alternative. Dimenhydrinate (Dramamine) may be superior to the benzodiazepines at least acutely.
Ménière’s disease. Syndrome with recurrent attacks of vertigo and tinnitus lasting hours to days and associated hearing loss (low frequencies lost first; discrimination is maintained). Generally have a feeling of ear fullness that resolves after episodes of vertigo. Brief, transient vertigo is not Ménière’s disease. May have nausea, vomiting, and ataxia. Onset age 30 to 60 years. Patients with newly suspected cases should be evaluated with MRI and audiometry. Sixty percent resolve spontaneously without treatment. Treatment includes bed rest, IV fluids (if unable to maintain hydration), antihistamines, and phenothiazines or diazepam (as above). Salt restriction and diuretics (such as hydrochlorothiazide or furosemide) may be helpful. If severe symptoms, surgical ablation may be performed (labyrinthectomy if hearing is lost; vestibular nerve section if hearing is preserved). See BPPV above for symptom control.
Migraine aura. Vertigo can arise as an aura to migraine. Other symptoms may include scintillating scotoma, homonymous hemianopsia, cortical blindness, diplopia, dysarthria, ataxia, and paresthesias. Patients are typically young women and adolescents. Symptoms last up to 30 minutes, and migraine headache occurs after the vertigo.
Treatment of basilar migraines should avoid vasoconstrictors, otherwise standard abortive and prophylactic migraine medications are appropriate.
Perilymph fistula occurs from a perilymphatic leak. Vertigo is often precipitated by prolonged standing, change in head position, coughing, sneezing, swallowing, straining, barotrauma, air travel, or loud noises. There is often an antecedent history of head trauma that results in a small tear in the oval or round window leading to a perilymph leak. Tends to be better in the morning and worse after being upright for a time. May be associated tinnitus and hearing loss.
Diagnosis: Pneumatic otoscopy reproduces symptoms. Often heals spontaneously. Surgical correction if ongoing symptoms.
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