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 OM 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

Diagnosis

• Weber test and Rinne test
• Otoscopic exam to r/o OM, OE, foreign bodies, perforated TM or cholesteatoma
• Remove impacted cerumen and re-examine
• Complete neurologic exam to r/o stroke
• Audiometric evaluation
• MRI to r/o acoustic neuroma, perilymphatic fistula, Ménière’s disease, vascular insufficiency, MS

Treatment

• Glucocorticoids orally (prednisone 1 mg/kg/day up to 60 mg maximum for 10-14 days or dexamethasone 300 mg daily for 3 days)
• Glucocorticoids locally (intratympanic instillation, dexamethasone 10 to 24 mg/mL or methylprednisolone 30 to 40 mg/mL) if refractory to oral GCs
• Antivirals for possible HSV-1 infection (valacyclovir 1g TID or famciclovir 500mg TID)

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

Follow-Up

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

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.