Sensorineural hearing loss (SNHL) is the most common type of permanent hearing loss. It’s caused by problems in your inner ear, like abnormalities in your cochlea, auditory nerves or other structures. It’s also known as nerve-related hearing loss because it affects the parts of the inner ear that send neural impulses to the brain.
There are several different types of sensorineural hearing loss, each with different underlying causes.
Presbycusis is age-related hearing loss, often caused by the loss of nerve hair cells in the cochlea. It usually comes on gradually. Initially, it reduces your ability to hear higher frequency sounds but over time it can make lower frequency sounds unclear too, making everyone sound like they’re mumbling.
Noise-induced hearing loss occurs when excessive noise, usually over a long period, damages the fine hairs in your inner ears that send messages to your brain. Work Safe Australia estimates that about a third of the Australian workforce works in environments where they’re exposed to too much noise at work, for example, in the manufacturing or construction industries. People who love listening to loud music may also be damaging their hearing. Noise-induced hearing loss can also happen after a one-off exposure to an intensely loud sound, such as an explosion.
Ototoxic medications or chemicals are substances that injure your cochlea or auditory nerve. Ototoxic medicines may also affect your vestibular system, which governs your balance and spatial awareness.
Hereditary hearing loss is a form of hearing loss that runs in families. Your genes might make you more susceptible to hearing loss by contributing to age-related hearing loss, causing some hereditary hearing impairment syndromes, or causing inner-ear mutations that affect your hearing, either at birth or in later life.
Traumatic hearing loss can happen after a head injury or operation that damages your auditory pathways.
Sudden sensorineural hearing loss happens when you notice a rapid loss of hearing in one or both ears. This could be due to medication, a trauma, the after-effects of a loud noise or an underlying condition like MS or diabetes. You should see a doctor quickly for assessment. In many cases, there’s no obvious cause (known as idiopathic) but early treatment may help.
In many cases, sensorineural hearing loss can’t be cured, but it can be treated. Treatment options include drugs, surgery, better management of any underlying conditions, and hearing aids.