Sensorineural hearing loss (SNHL)
What is sensorineural hearing loss? – Definition of sensorineural hearing loss
A sensorineural hearing loss (also known as SNHL) is a hearing loss that results from loss of or damage to the tiny hair cells in the cochlear in the inner ear. The tiny hair cells in the cochlear transmit sound from the inner ear through the hearing nerve to the brain.
There are different types of sensorineural hearing loss. You can have a sensorineural hearing loss in one ear (unilateral hearing loss) or in both ears (bilateral hearing loss). A sensorineural hearing loss can be a sudden sensorineural hearing loss. A sensorineural hearing loss can also be a high-frequency hearing loss or a low-frequency hearing loss.
Difference between a sensorineural hearing loss and conductive hearing loss
A sensorineural hearing loss is a type of hearing loss that differs from a conductive hearing loss, where the ability to conduct sound from the outer ear and middle ear into the inner ear is reduced or lost.
If you want to find more information on hearing loss in general, please read our article “What is hearing loss?”.
What causes sensorineural hearing loss?
A sensorineural hearing loss is typically be caused by:
- Ageing
- Noise
- Certain types of diseases
- Genes (inherited)
- Rubella during pregnancy
- Low birth weight
- Head/ear injuries.
But a sensorineural hearing loss can be caused by other causes as well.
Everybody loses some of the tiny hair cells in the cochlea throughout life, while their hearing gradually becomes less precise. This is a natural part of aging. Ageing is one of the major causes of a sensorineural hearing loss. A sensorineural hearing loss caused by age is called an age-related hearing loss or Presbyacusis.
However, the hair cells can also be damaged by excessive noise. As a result of prolonged exposure to high intensity noise for example from the work environment or from listening to loud music, sensorineural hearing impairment is becoming more common.
You can also suffer from sensorineural hearing loss having been exposed to diseases such as mumps, meningitis, multiple sclerosis, ménières disease or if you have used certain drugs, in particular aspirin, cisplatin, quinine or the antibiotics streptomycin and gentamicin.
Sensorineural hearing impairment may also occur if your mother has had rubella (German measles) during pregnancy, or if your birth weight was low.
Sensorineural hearing loss can be inherited (genetic hearing loss) and finally you may lose your hearing ability due to head/ear injuries.
A ski slope hearing loss and a cookie bite hearing loss are two classical types of a sensorineural hearing loss. A ski slope hearing loss mostly affects the high frequencies, whereas a cookie bite hearing loss mostly affects the mid-frequencies.
If you have a sensorineural hearing loss in both ears (bilateral sensorineural hearing loss) and there is a great difference in the hearing loss between the ears, it is called an asymmetric sensorineural hearing loss.
What are the symptoms of a sensorineural hearing loss?
Typically, a sensorineural hearing loss develops gradually and slowly becomes worse and worse. It does not happen from day to another unless it is a sudden sensorineural hearing loss (see below). In this way, we often do not notice that our hearing has becomes worse.
Some of the common and classic symptoms of a sensorineural hearing loss are:
- Difficulties hearing voices in places with background noise, for example at parties, restaurants or family gatherings
- Difficulties hearing or understand females’ or children’s voices
- Difficulties understanding speech on the TV or listening to the radio and turning up the volume
- Problems hearing soft or high-pitched sounds such as the clock ticking, the refrigerator humming or the birds singing
If you are not sure whether you are suffering from SNHL, you can find more information about the general signs of hearing loss.
How is sensorineural hearing loss diagnosed?
A sensorineural hearing loss is identified and diagnosed by a hearing professional who examines your ears and carries out a hearing test that comprises of a series of different tests.
Sensorineural hearing loss on an audiogram
The results of the hearing test are presented in an audiogram. The specific sensorineural hearing loss can be illustrated in the audiogram. The audiogram will show the degree of the hearing loss and tell which frequencies are affected by the sensorineural hearing loss by showing the hearing levels at different frequencies in both ears.
Read more on how to read an audiogram.
Is sensorineural hearing loss permanent?
Yes, unfortunately a sensorineural hearing loss is permanent as the hair cell in the inner ear cannot be repaired or replaced. And – regardless of whether it is a bilateral or unilateral hearing loss – the hearing does not recover fully or partly over time or by itself. The hearing that is lost is lost permanently. An age-related hearing loss, for example, typically worsens over time.
Can a sensorineural hearing loss be cured? In most cases unfortunately not. A sensorineural hearing loss is normally treated with hearing aids or hearing implants. Certain types of sudden sensorineural hearing losses can in some cases be cured but here it is important to seek medical help immediately.
What kind of treatments exist for sensorineural hearing loss?
People with sensorineural hearing loss cannot regain their hearing. The treatment of sensorineural hearing loss will often be the use of hearing aids. People with a more severe or profound sensorineural hearing loss can be treated with hearing implants such as cochlear implants.
A hearing test carried out by a hearing professional will detect if you have a sensorineural hearing loss.
Sudden sensorineural hearing loss
A certain type of sensorineural hearing loss is called sudden sensorineural hearing loss or just sudden hearing loss. If you experience a sudden sensorineural hearing loss you should contact a doctor as soon as possible.
Can sensorineural hearing loss get worse?
Yes, a sensorineural hearing loss can get worse. Some types of sensorineural hearing loss develop over time such as an age-related hearing loss, where people typically lose more and more of their hearing ability over time. Other types of sensorineural hearing loss are more stable. It always depends on the cause of the hearing loss. If you experience your hearing loss getting worse, it is important to get your hearing tested and get your hearing aids adjusted to the actual hearing level.
Can children have sensorineural hearing loss?
Children can also have a sensorineural hearing loss. Most commonly, the hearing loss is caused by genetic defects or infections during pregnancy. In rare cases, the hearing loss can be caused by noise. Learn more about hearing loss in children.
Are there other types of hearing loss?
We differentiate between two main types of hearing loss: sensorineural and conductive hearing loss but there are also other types or categories of hearing loss.
Read about the types of hearing loss.