Sensorineural hearing loss

Inside your inner ear sits the cochlea – a hollow, spiral-shaped bone that plays a huge role in our hearing pathway. The cochlea contains tiny hairs called stereocilia, which convert the vibrations from sound waves into neural signals. The auditory nerve then sends these messages to the brain to interpret as sounds – but when these hairs are damaged or destroyed, whether by loud sounds or simple age-related degeneration, sensorineural hearing loss can occur.

Damage to or destruction of these fragile hairs in the cochlea can occur with exposure to sounds of 85 decibels or more. What do 85 decibels sound like, exactly? Noise levels equivalent to a blender, heavy traffic while in the car, a noisy restaurant or even the cinema are around 85 decibels. When 30 to 50 per cent of these hairs are damaged, you may notice your hearing is reduced.

While sensorineural hearing loss is the most common type of hearing loss, accounting for more than 90 per cent of hearing loss in adults, the term ‘sensorineural hearing loss’ isn’t often used outside of medical contexts. But it’s certainly a good idea to understand it if you’ve been given a sensorineural hearing loss diagnosis by your healthcare provider. 

Sensorineural hearing loss can be caused by a wide range of conditions but most commonly by the natural ageing process, which accounts for around 90 per cent of this type of hearing loss. It affects 1 in 7 people over the age of 65. Age-related sensorineural hearing loss is known as presbycusis, and is a result of all the accumulated noise you’ve been exposed to over the course of your life. If you’ve been exposed to excessive amounts of loud sound throughout your life, presbycusis may onset at an earlier age.

Age-related sensorineural hearing loss usually affects high-pitched sounds first and, over time, may start to affect lower-pitched sounds, too.

Some of the causes of sensorineural hearing loss are:

• Age – gradual deterioration in hearing across both ears in high-pitched sounds.
• Traumatic exposure to loud noise – this may be from a sudden, very loud sound or repeated exposure to high-level sound. Hearing loss could be permanent or temporary.
• Head injury – this can cause trauma to the cochlea and nerves in the ear
• Viral infections of the inner ear and auditory nerve
• Some drug treatments
• Family history
• Industrial noise exposure
• Meniere’s disease

Sensorineural hearing loss may also be congenital, meaning it is present from birth. 

While many people diagnosed with hearing loss experience a slow onset, sudden sensorineural hearing loss – a loss of hearing over three or fewer days – can also occur. A sudden loss of hearing may be caused by infection, stroke, head injury, some medications and other health conditions. Conductive hearing loss can also have a sudden onset.

It’s important to note that sudden sensorineural hearing loss is an emergency, and you should go to your local hospital’s emergency department if this occurs.

If you’re having trouble with your hearing, it’s important to visit a healthcare professional for diagnosis. To determine whether you have conductive vs sensorineural hearing loss, your doctor may first perform a physical examination and/or tests using a tuning fork (where and how you hear certain sounds from the instrument can indicate the type of hearing loss). If a sensorineural hearing loss diagnosis is suspected, you may be referred to an audiologist for an audiogram.

Hearing aids are small electronic devices that increase sound volume to help you hear better. They are often used in cases of sensorineural hearing loss and can be a fantastic treatment option for those facing this type of hearing loss.

They come in a huge range of styles and capabilities to suit not only each individual’s hearing needs but your lifestyle and budget. Bay Audiology clinics offer a variety of hearing aids, and our specialists can help you find the right solution for you. Find your nearest Bay Audiology clinic and book an appointment today to take a hearing test and discuss your hearing needs.