Definition:
- Loss of significant hearing (>30 dB in at least three adjacent frequencies) occurring over <72 hours.
- Diagnosis of exclusion.
Epidemiology:
- Incidence: 20 per 100,000 people per year.
- Accounts for up to 90% of sudden sensorineural hearing loss (SSNHL).
- Average age of onset: 40–50 years.
- Unilateral in 95–100% of patients.
- Bilateral loss tends to occur in older populations with lower recovery rates.
Symptoms:
- Frequently associated with tinnitus (70% of cases).
- Dizziness occurs in up to 40% of cases, sometimes leading to nausea and vomiting.
- Other symptoms: ear fullness, headache, and upper airway viral infection symptoms.
- Ménière’s triad: hearing loss, tinnitus, and dizziness.
Diagnosis:
- Often missed in children, especially if unilateral.
- Requires exclusion of other known causes.
Prognosis:
- Spontaneous recovery in 45-60% of patients.Detailed recovery estimates:
- 25% experience total spontaneous recovery.
- 50% experience partial recovery.
- 25% experience no recovery.
- Better prognosis:
- Low frequency hearing loss.
- Less severe hearing loss at presentation.
- Early commencement of treatment.
- Severe hearing loss appears to respond better to steroid therapy.
- Worse prognosis:
- Patients aged < 15 years or > 60 years.
- Presence of vertigo.
Treatment:
- Mainstay of treatment: Early initiation of oral steroids.
- Prednisolone at a dose of 1 mg/kg/day (maximum 60 mg/day).
- Treatment duration: 7–14 days.
- Tapering is not required with shorter courses.