Sudden Sensorineural Hearing Loss (SSNHL)

Sudden sensorineural hearing loss (SSNHL) is commonly defined as a loss of at least 30 dB at 3 consecutive frequencies developing within 72 hours. Lesser or uncertain losses may still need urgent treatment. ^{ENT UK SSNHL}

Unexplained sudden loss with onset within 30 days should be assessed within 24 hours. Exclude conductive loss and screen for stroke, trauma, infection and systemic causes. ^{NICE NG98}

For presumed idiopathic SSNHL, obtain audiometry, offer early corticosteroid treatment and request MRI IAM/CPA. ^{ENT UK SSNHL NHS Highland2025}