Sudden Sensorineural Hearing Loss (SSNHL) requires immediate medical attention. This condition involves a rapid decrease in hearing ability, and prompt evaluation by a healthcare professional is important for potential treatment outcomes.
What is Sudden Sensorineural Hearing Loss
Sudden Sensorineural Hearing Loss (SSNHL) is a rapid loss of hearing occurring instantly or over up to 72 hours. It often affects only one ear. “Sensorineural” means the problem is in the inner ear, involving damage to the cochlea’s tiny hair cells or the auditory nerve, which transmits sound signals to the brain.
For diagnosis, hearing loss must be at least 30 decibels (dB) across three consecutive audiometric frequencies. A 30 dB drop makes normal conversational speech sound like a whisper. SSNHL can affect individuals of any age, but is most common in adults between 50 and 60.
Identifying Symptoms and Potential Causes
The primary symptom of SSNHL is a sudden reduction in hearing, frequently in one ear. Some individuals might experience a loud “pop” sound immediately before the hearing fades, while others simply wake up with the noticeable difficulty. Alongside the hearing loss, other symptoms may include tinnitus, a ringing, buzzing, or whooshing sound in the affected ear.
Many also report a feeling of fullness or pressure in the ear, known as aural fullness. Dizziness or problems with balance, referred to as vertigo, can also accompany SSNHL. While these symptoms can be alarming, it is common for individuals to initially dismiss them, attributing them to conditions like allergies, a sinus infection, or earwax buildup.
The majority of SSNHL cases are considered idiopathic, meaning the specific cause remains unknown. However, various factors are suspected to contribute to the condition:
Viral infections that may cause inflammation or swelling in the cochlea.
Autoimmune diseases, where the body’s immune system mistakenly attacks its own tissues, can sometimes target the inner ear.
Vascular issues, such as problems with blood flow to the cochlea.
Physical trauma to the ear or head.
Rarely, a non-cancerous growth on the auditory nerve, known as an acoustic neuroma or vestibular schwannoma.
Immediate Action and Treatment Options
Upon experiencing any sudden decrease in hearing, immediate medical attention is important, ideally within hours or days, to improve the chances of hearing recovery. A healthcare provider will perform a physical examination to rule out conductive hearing loss, caused by obstructions in the outer or middle ear. The primary diagnostic tool is an audiogram, a comprehensive hearing test by an audiologist. This test measures how loud different frequencies of sound need to be before they can be heard, confirming the degree and type of hearing loss.
Further investigations may include magnetic resonance imaging (MRI) to check for underlying causes like an acoustic neuroma, along with blood and balance tests. The main treatment for SSNHL, particularly for idiopathic cases, involves corticosteroids. These can be administered orally, such as prednisone, or through intratympanic injections directly into the middle ear. Corticosteroids work by reducing inflammation and swelling within the cochlea.
Early intervention significantly impacts the effectiveness of treatment. While some individuals may experience spontaneous hearing recovery, particularly those with mild to moderate hearing loss, initiating steroid therapy within two weeks of onset generally improves the prognosis. Other potential adjunctive therapies, such as hyperbaric oxygen therapy, may be considered, sometimes in combination with steroids, especially if initial treatments are not fully effective. If full hearing recovery is not achieved, options like hearing aids or cochlear implants can assist in managing residual hearing loss.