Why Can’t I Hear? Types and Causes of Hearing Loss You Need to Know
Have you ever thought about why some people have trouble hearing? Is it something they were born with? Did they lose their hearing because of age? Was the hearing loss noise-induced? Hearing loss presents in many shapes, degrees and forms, affecting people of all ages. It is important to understand what causes it so that you can protect your own hearing and identify hearing issues early.
All cases of hearing loss are not the same. The type of hearing loss determines the most appropriate treatment approach. What kind of hearing loss you have, depends on what part of your ear has sustained damage. Hearing loss falls into three categories: Sensorineural, conductive and mixed.
Types of Hearing Loss
- Sensorineural hearing loss: Sensorineural hearing loss occurs in the inner ear or the nerve connecting the inner ear to the hearing centres of the brain.
- Conductive hearing loss: Conductive hearing loss occurs in the mechanical part of the ear, the ear canal or middle ear.
- Mixed hearing loss: Mixed hearing loss is a combination of the two.
How Does Hearing Loss Occur?
Let us briefly look at the structure of the ear to understand how hearing loss can occur.
The ear is made up of 3 sections:
- The outer ear: Consisting of the ear and the ear canal.
- The middle ear: Home to the mechanical portion of the ear, consisting of the three smallest bones in the body and the eardrum.
- The inner ear: Houses the cochlea, the hearing and balance organ.
When all the three sections of the ear work together in unison, hearing is seamless. The sound waves are directed through the ear to the hearing processing centre in the brain. It’s almost magical! However, when there is a breakdown along the way, a person can experience mild to severe hearing loss. Let’s explore the main types of hearing loss.
Sensorineural Hearing Loss
This is the most common type of hearing loss. It occurs when there is damage to the hair cells in the inner ear or damage to the hearing nerve between the inner ear and the hearing centres of the brain. Even though the mechanics of the ear can be working well, damage to the inner ear and the resulting hearing loss are usually permanent. It can not be medically or surgically corrected. Sensorineural hearing loss can be caused by damage that occurs with time and ageing, exposure to loud noises, genetic conditions or disease.
Genetic conditions and birth defects.
If a child is born with sensorineural hearing loss it is most likely caused by a genetic syndrome, inherited from a parent. It can also be the result of an infection that occurred during pregnancy (such as rubella) or birth trauma. These types of sensorineural hearing loss can progressively get worse as time passes.
Ageing, trauma and exposure to loud noise.
Sensorineural hearing loss can develop at any time and has many possible causes. The most common causes are ageing (a type of hearing loss called Presbycusis) and ear damage from loud noise. The more loud noise a person is exposed to, the greater the degree of noise-induced hearing loss usually is.
Whilst noise-induced hearing loss is preventable, it is much harder to avoid hearing loss caused by a natural decline in hearing. As we age, our ears – like any body part, wear out slowly. When the time comes, it is wise to consider getting hearing aids to keep enjoying the sounds of daily life.
Viral infections, disease and medication.
Sensorineural hearing loss can also be caused by viral infections, certain medications, diabetes, tumours in the inner ear or the hearing nerve, cardiovascular diseases, autoimmune diseases and Meniere’s syndrome.
This type of hearing loss is a medical emergency: It can feel like you’ve lost your hearing overnight! The good news is, if caught early, it can be treated with medication. There is a good chance of hearing recovery.
Sensorineural hearing loss can affect both the volume and clarity of sound. This type of hearing loss affects different frequencies of sound in different people. The most common causes of sensorineural hearing loss, ageing and ear damage from loud noise, tend to cause high-frequency hearing loss.
This makes people misunderstand, rather than not hear at all. People commonly report “I can hear people talking, but not what they are saying”. Generally, this sort of hearing loss causes more difficulty in background noise and for understanding women’s and children’s high-pitched voices.
Additionally, a lot of people with sensorineural hearing loss will often have some degree of ringing in their ears, also called tinnitus.
Sensorineural hearing loss, unfortunately, is permanent. No medical or surgical treatment can restore the hair cells in the inner ear or repair damage to the hearing nerve. However, sensorineural hearing loss can be managed with hearing aids and other devices.
Today’s hearing aids are small, discrete and easy to use. The wearer only has to put them in and the hearing aids will automatically adjust to the various environments and sounds. Some hearing aids can also connect via bluetooth to devices like phones, ipads and tvs. Should hearing aids not be appropriate, other devices such as cochlear implants may be an option.
Conductive Hearing Loss
Conductive hearing loss occurs when there is damage or an obstruction in the outer canal or middle ear, but the main hearing organ, the cochlea, is still performing optimally. It occurs when sound is prevented from travelling to the inner ear as a result of problems in the ear canal, the eardrum, the bones behind the eardrum or the space in the middle ear. Conductive hearing loss can be temporary or permanent, occur from birth or develop over time. It can often be medically or surgically corrected.
Obstructions of the ear canal
Something as simple as wax blocking the ear canal can cause a noticeable conductive hearing loss. Other causes include a hole in the eardrum or fluid behind the eardrum. Abnormal bone growth can also cause a conductive hearing loss.
Ear infections are common in children and can cause speech and language delays. An obstruction prevents sound from reaching the inner ear, resulting in a drop in hearing. These structural issues are not indicators of noise-induced hearing loss. In many cases there is medical treatment that can help improve the problems causing the hearing loss, as the hearing organ itself is still in good condition.
In conductive hearing loss, the nerve portion of the hearing is normal. Conductive hearing loss is generally a lack of volume rather than clarity. Tinnitus can also be associated with conductive hearing loss.
Some conditions causing conductive hearing loss may cause hearing to fluctuate. Conductive hearing loss may also cause some of the following symptoms: Pain and discomfort in one or both ears, feelings of pressure and fullness in one or both ears, discharge from one or both ears, and their own voice may sound louder than usual.
Many causes of conductive hearing loss can be medically or surgically treated. Wax impaction, narrowing of the ear canal, exostosis, perforations, middle ear fluid, tumours in the middle ear and damage to the middle ear bones can all be medically or surgically corrected, potentially restoring the hearing. If the hearing can not be restored, traditional hearing aids or bone-anchored implantable devices may also be an option.
Mixed Hearing Loss
Mixed hearing loss is a combination of sensorineural hearing loss and conductive hearing loss. Is it common to have both conductive hearing loss and a sensorineural hearing loss at the same time? Yes, definitely! Here is an example: If a factory worker has noise induced hearing loss from prolonged exposure to loud sounds and then has one ear completely blocked with ear wax, this would result in a mixed hearing loss.
This type of hearing loss needs specialised testing to accurately identify the source of the hearing problem. In the example above, the degree of noise induced hearing loss would need to be identified as well as the degree of loss caused by the wax.
Certain health conditions
Mixed hearing loss can occur in certain health conditions. Otosclerosis, for example, can cause damage to both the mechanical and nerve part of the hearing system. Trauma may also cause mixed hearing loss. Sometimes mixed hearing loss can develop over time. For example, if someone has conductive hearing loss then gets ear damage from loud noise, they can end up with mixed hearing loss.
Symptoms of mixed hearing loss will be a combination of those listed for sensorineural hearing loss and conductive hearing loss.
Treatment options for mixed hearing loss will depend on the underlying cause. Generally, the nerve component of the loss is permanent and can not be medically or surgically resolved. But the conductive component may be corrected.
Improve Your Quality of Life Today
So now that you now know about the types of hearing loss, you can see that not all cases of hearing loss are the same. If you can take away something from this article, it is to protect your hearing at all cost. Save your ears from noise-induced hearing loss, prevention is, after all, better than cure.
Having a proper hearing test with a qualified audiologist will help identify the type and degree of hearing loss you may already have. Nowadays, there are treatment options available for all hearing losses and no-one should be isolated or struggling to communicate due to untreated hearing loss.
Our audiologists at Attune Hearing seek to understand your specific needs to recommend the best solution for you. Call us today to arrange an appointment at your local Attune clinic.