Sudden sensorineural hearing loss

Background

Epidemiology

• Mostly idiopathic
• Prognosis depends on severity of hearing loss
• Incidence estimates range from 2-20 per 100,000 people per year
• Most commonly 43-53 years of age
• Men and women affected equally

Clinical Features

• Immediate/rapid hearing loss or hearing loss upon awakening
  • Mostly unilateral hearing loss
• Sensation of blocked or full ear, patient doesn’t recognize hearing is gone
• Difficulty in localizing sound
• Tinnitus is common
• Some patients report vertigo
• Occasionally ear pain is present
• No sign of obstruction or otitis media on physical exam

Differential Diagnoses

• Acute stroke, usually AICA occlusion
• Multiple Sclerosis
• Meningitis
• Vestibular schwannomas
• Migrainous infarction
• Acute otitis media
• Traumatic TM rupture

Ear Diagnoses

External

• Auricular hematoma
• Auricular perichondritis
• Cholesteatoma
• Contact dermatitis
• Ear foreign body
• Herpes zoster oticus (Ramsay Hunt syndrome)
• Malignant otitis externa
• Otitis externa
• Otomycosis
• Tympanic membrane rupture
  • Otic barotrauma

Internal

• Acute otitis media
  • Bullous myringitis
• Chronic otitis media
• Mastoiditis

Inner/vestibular

• Labyrinthitis, vestibular neuritis
• Meniere's disease
• Sudden sensorineural hearing loss

Evaluation

• Weber test and Rinne test to rule out conductive hearing loss (poor man's version is to have patient hum with mouth closed and ask which side they hear it louder on; ipsilateral for conductive and contralateral for sensorineural)
• Otoscopic exam to rule out OM, OE, foreign bodies, perforated TM or cholesteatoma
• Remove impacted cerumen and re-examine
• Complete neurologic exam to rule out stroke
• Audiometric evaluation (typically as outpatient)
• Consider MRI to rule out acoustic neuroma, perilymphatic fistula, Meniere's disease, vascular insufficiency, MS; usually can happen as outpatient
• No role for routine laboratory testing or CT head imaging in absence of other findings

Management

• Glucocorticoids orally (prednisone 1mg/kg/day up to 60mg maximum for 10-14 days or dexamethasone 300mg daily for 3 days)
• Glucocorticoids locally (intratympanic instillation, dexamethasone 10 to 24mg/mL or methylprednisolone 30 to 40mg/mL) if refractory to oral GCs
• Antivirals for possible HSV-1 infection (valacyclovir 1g TID or famciclovir 500mg TID) are not routinely indicated in the absence of exam findings

Disposition

Outpatient follow-up with:

• Audiogram in six months after initial diagnosis
• Possible auditory rehabilitation for patients with permanent hearing loss
• Consider assistive hearing devices

Prognosis

• Spontaneous improvement is common
• Better prognosis if high- or low-frequency hearing loss pattern rather than flat across all frequencies
• Around 2/3 of patients will regain hearing in the affected ear
• Worse prognosis in older patients
• Worse in patients with vertigo

See Also

• Ear diagnoses

References

1. Weber PC. Sudden sensorineural hearing loss. In: UpToDate. Accessed Sept 22 2014.
2. Weber PC. Etiology of hearing loss in adults. In: UpToDate. Accessed Sept 22 2014.
3. Molina, FJ. Hearing Loss, Chapter 18. Tintinalli’s Emergency Medicine.