Sensorineural hearing loss occurs when problems with hearing nerves and functions of the inner ear mean that sound is no longer conveyed properly to the brain.

Hearing loss can be a confusing and frustrating condition, especially if you don’t know what you’re experiencing or why you are having problems with your hearing. Here, we’ll look more closely at sensorineural hearing loss, its causes and how you can potentially reverse it.

What is sensorineural hearing loss?

There are three parts to your ear: the outer ear, the middle ear, and the inner ear. Sensorineural hearing loss affects the inner ear.

The inner ear contains the cochlea, where vibrations coming through the ear canal are changed to electrical neural signals, which are then transferred to the brain through the auditory (hearing) nerve.

Sensorineural hearing loss occurs when one, or both, of these functions of the inner ear are damaged. Damage to the cochlea or auditory nerve means that sound vibrations are not converted into impulses and carried to the brain in a way it understands.1

This type of hearing loss is characterised by having trouble hearing quiet or high-pitched sounds. If you’re affected by sensorineural hearing loss, you may feel as though people are mumbling or sounds may seem softer.

Ageing
Presbycusis, or hearing loss due to ageing, is a common type of sensorineural hearing loss. If you are over 60 years old and have hearing problems, there is a chance you could have presbycusis.

Presbycusis reduces the high-frequency hearing of those affected — so if you’ve noticed your hearing isn’t quite what it used to be, make sure you see an audiologist. They’ll check your hearing, and will be able to recommend treatment to help improve your hearing and get you back to normal.

Loud noises
The most common cause of sensorineural hearing loss, loud noises directly damage your cochlear structures. You can avoid being affected by loud noises by protecting your ears.

Infection
Viral infections in the inner ear can also lead to sensorineural hearing loss. Hearing loss caused by infection can be sudden, unlike the gradual hearing loss in presbycusis. Viral infections during pregnancy, such as Cytomegalovirus, could also cause hearing loss in the child.

Congenital or hereditary
Sometimes babies can have sensorineural hearing loss at birth. The reasons can be genetic or hereditary, where a malformation of the cochlea or auditory nerves lead to the hearing loss.

Ménière’s disease
When the fluid pressure is too high in the inner ear, the result is Ménière’s disease. The symptoms are usually sudden and episodic, characterised by tinnitus (ringing of the ear) and dizziness.

Medication
Certain medications, such as some antibiotics and chemotherapy, can be harmful to the ear (ototoxic) and can damage the cochlea or other parts of the inner ear. The majority of medications are harmless, but if you experience a loss of hearing after starting a new medication or therapy, you should speak to your doctor.

Is sensorineural hearing loss curable?

Different causes of sensorineural hearing loss need different interventions. In the case of sudden sensorineural hearing loss especially, it’s important to see your audiologist as soon as you can, ideally within 72 hours, as some or all of your hearing could be recovered.

Unlike gradual loss or congenital causes, sudden onset hearing loss can be reversed — as long as it is identified and treated immediately.

If the cause of hearing loss is an infection or ototoxic therapy, however, then it’s important to speak to your GP first. They’ll be able to help you understand what your next steps should be — whether removal of the medication that may be causing hearing loss, or by helping to locate any other causes.

Corticosteroid (oral or injection)
For sudden sensorineural hearing loss, your doctor may prescribe treatment with steroids to alleviate hearing loss. These come in two forms: tablets or an injection through the eardrum (intratympanic injection).

Oral steroid is usually the first-line therapy, while the steroid injection would be the choice when the oral steroid alone is not sufficient. Studies have shown both the oral and injection forms of steroid therapy are equally effective in treating hearing loss.4

What happens if sensorineural hearing loss can’t be reversed?

It’s not always possible to reverse sensorineural hearing loss, particularly if it’s gradual or congenital hearing loss. In these cases, however, there are other treatment options:

Hearing aids
If the sensorineural hearing loss is mild, sound amplification with hearing aids is usually the best option. Older people with mild presbycusis and those with mild irreversible sensorineural hearing loss, but intact cochleae, are good candidates for hearing aids.

Specsavers provide free hearing tests for those who might need hearing aids. The hearing test evaluates many parameters of hearing loss, including sound frequencies affected by and the severity of hearing loss.

Cochlear implants
The most common remedy for irreversible sensorineural hearing loss is cochlear implants. Your doctor will usually only recommend cochlear implants if you are totally deaf, or experience profound sensorineural hearing loss.

To know more about the different types of hearing loss, visit our dedicated hearing resource, which will help you understand everything about hearing impairments, causes and treatments.

References

  1. Weber PC. Etiology of hearing loss in adults - UpToDate. Published October 30, 2018. https://www.uptodate.com/contents/etiology-of-hearing-loss-in-adults?source=history_widget#H40. Accessed June 9, 2019
  2. Lin, F. R. (2011). Hearing loss and cognition among older adults in the United States. The Journals of Gerontology. Series A, Biological Sciences and Medical Sciences, 66(10), 1131–1136. https://doi.org/10.1093/gerona/glr115