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Pathophys and Cause

Cause:Idiopathic

Pathophys:

Endolymphatic hydrops in scala media causes increased pressure in scala media. Probably due to diminished resorption causing organ of corti damage and semicirc canal involvement

Attack probably represents an endolymphatic rupture with mixing of endo- and perilymph; endolymph has an intracellular ionic content

Epidemiology

Onset usually in 5th decade

Signs and Symptoms

Sx:

Si:Decreased auditory discrimination, in contrast to conductive losses; recruitment

Complications

Complete hearing loss in affected ear

Lab and Xray

Lab:Audiometry shows sensorineural loss without air-bone gap. Recruitment of sound so that loudness increases abruptly with slight increase in decibel level, ie, abnormally loud above their abnormally high threshold; this is the distinguishing feature between cochlear (Ménière's, presbycusis) and retrocochlear disease

Treatment

Rx:

Salt, caffeine, and alcohol restriction

Medications:

  • Benzodiazepines in low dose, tapered to minimally effective dose, like diazepam (Valium) 2 mg po tid (never more) initially then tapered over 1-2 wk to 2 mg qd; or lorazepam (Ativan) 1 mg sl/po
  • Antihistamines (Benadryl)
  • Antivertigo drugs (scopolamine, meclizine [Antivert], dimenhyrdinate [Dramamine], phenothiazines)
  • Diuretics prophylactically, eg, thiazides
  • Streptomycin, perhaps, 2-3 gm im qd to produce bilateral nerve damage in 10-20 d, unused now

Surgical: rarely need; labyrinthectomy through middle ear if hearing already gone there; endolymphatic saccule to subarachnoid space shunt; sacculotomy; 8th nerve section