Sudden Deafness (Sensorineural Hearing Loss)

What is Sudden Sensorineural Hearing Loss (SSNHL)?

Sudden Sensorineural Hearing Loss (SSNHL), often referred to as sudden deafness, is a rapid loss of hearing that occurs over a period of up to 72 hours. It typically affects one ear and can vary in severity. Accompanying symptoms may include:

• Distortion of sounds in the affected ear
• Tinnitus (ringing or buzzing in the ear)
• A feeling of fullness or blockage in the ear
• Dizziness or imbalance
• Nausea or vomiting
• Feelings of anxiety.

SSNHL is relatively rare, with an incidence of five to 20 cases per 100,000 people annually. It most commonly affects people aged between 30 and 60 years, with both males and females being equally susceptible.

Causes of SSNHL

In many cases (over 75%), the exact cause of SSNHL remains unknown (idiopathic). However, potential causes include:

• Viral infections affecting the cochlea
• Blood flow abnormalities in the cochlea
• Autoimmune inner ear diseases
• Exposure to ototoxic drugs (medications harmful to the ear)
• Trauma or head injury
• Rarely, growths on the auditory (hearing) nerve.

Diagnosis of SSNHL

A healthcare professional will conduct a thorough medical history and physical examination. Diagnostic tests may include:

• Audiometry: To assess the degree and type of hearing loss.
• Imaging Studies: Such as MRI scans, to rule out structural abnormalities or growths.
• Blood Tests: To identify potential underlying causes.

Treatment options

Early treatment is vital for better outcomes. Common treatments include:

• Corticosteroid tablets: These are the primary treatment for SSNHL, aiming to reduce inflammation in the cochlea. They are most effective when started within seven days of onset but may still offer benefit if initiated up to six weeks later.
• Intratympanic Steroid Therapy: This may be offered to patients who responded partially to oral corticosteroids, saw no improvement or were seen after the ideal treatment window. In this approach, steroids are injected directly through ear drum as a last resort to save the hearing.

Prognosis and recovery

Current studies suggests that 33-66% of people may have spontaneous recovery. The likelihood of hearing recovery depends on several factors:

• Severity of hearing loss: Milder cases have a higher chance of recovery
• Timeliness of treatment: Starting treatment within seven days improves outcomes
• Presence of other symptoms: The absence of vertigo is associated with better recovery.

Some patients experience significant improvement within one to two weeks, but some may continue to recover over several months.

Unfortunately, some patients may not recover their hearing despite treatment. In these cases, your doctor will recommend helpful rehabilitative devices such as hearing aids.

Contact numbers

We hope that you have found this information useful. If you have any questions or are worried about anything, please speak to the following Dorset County Hospital staff:

ENT secretaries: 01305 255832 or 01305 255510

About this leaflet

Authors: Dr Chevaun Nelson and Lucy Swaby (ACP)
Written: June 2025
Approved: June 2025
Review Date: June 2028
Edition: v1

If you have feedback regarding the accuracy of the information contained in this leaflet, or if you would like a list of references used to develop this leaflet, please email patientinformation.leaflets@dchft.nhs.uk