Conductive hearing loss is a type of hearing loss that occurs when sound waves are unable to pass through the outer or middle ear into the inner ear.
In this case, the hearing loss patient’s inner ear is properly functioning, but it is unable to send any sound waves to the brain for interpretation because no sound is getting to it from the outer and middle ear.
Conductive hearing loss can be temporary or permanent, depending on the cause. In most cases, treating the cause of the hearing loss restores hearing to normal.
There are two types of conductive hearing loss: Unilateral conductive hearing loss and bilateral conductive hearing loss.
Unilateral Conductive Hearing Loss
Unilateral conductive hearing loss is a type of conductive loss that affects one ear. The hearing loss patient suffers conductive hearing loss in one ear while the other ear has normal hearing.
Unilateral conductive hearing loss can be acquired or congenital. An example of congenital unilateral conductive hearing loss is microtia in one ear. In this situation, one of the child's ears is perfectly formed while the other ear is malformed or deformed. The malformed ear is often nonfunctional and has to be corrected with surgery.
Unilateral conductive hearing loss can be hard to detect because of the functioning of the good ear. The hearing loss patient is often able to communicate, hear and respond to environmental noise without any difficulties. In most cases, the patient begins to suspect something is wrong with his hearing when he has to turn his good ear toward the direction of a sound to hear it.
The subtle nature of unilateral conductive hearing and the inability to diagnose it early often causes a delay in hearing loss treatment. This is dangerous because the root cause must have done almost irreversible damage to the ears by the time treatment commences.
Bilateral Conductive Hearing Loss
A bilateral conductive hearing loss is a type of conductive hearing loss that affects both ears. It is also referred to as double-sided hearing loss.
Bilateral Conductive hearing loss can be symmetrical or asymmetrical.
Symmetrical Bilateral Conductive Hearing Loss
A bilateral conductive hearing loss is said to be symmetrical when the severity of the symptoms of the hearing loss in both ears is the same. This type of bilateral hearing loss has serious effects on the hearing and communication of people who have it. Communication is more difficult for them.
Asymmetrical Bilateral Conductive Hearing Loss
Bilateral conductive hearing loss is said to be asymmetrical when there is hearing loss in both ears but varying degrees of symptoms in each ear. In this case, the degree of hearing loss symptoms is worse in one ear than the other.
Even though the second ear is also affected by hearing loss, the mildness of the hearing loss symptoms in it makes it possible for the hearing loss patient to use the "good" ear for hearing.
Causes of Bilateral Conductive Hearing Loss
Several factors can cause bilateral conductive hearing loss. The causes are either congenital or acquired. Congenital causes of bilateral conductive hearing loss are factors that cause hearing loss before birth. Acquired causes are factors that cause bilateral conductive hearing loss after birth.
As already stated, the causes of bilateral conductive hearing loss can always be found either in the outer ear or the middle ear. The inner ear is not affected.
Below are common causes of bilateral conductive hearing loss.
1. Earwax Blockage
The excessive build-up of earwax in both ears can cause bilateral conductive hearing loss. When the two ears produce earwax beyond the normal level, it becomes hard for the body to get rid of it.
This causes the excess earwax to accumulate, solidify and create a blockage in the ear canal. This blockage prevents the transmission of sound from the outer ear to the middle ear.
2. Swimmer's Ear
Swimmer's ear is also known as Otitis Externa. It is an infection of the outer ear canal. The infection runs from the eardrum to the outside of the head.
A swimmer's ear occurs when water is left in the ear after swimming. The presence of water creates a moist environment for bacteria or fungi to grow.
Symptoms of swimmer's ear include; redness of the ears, difficulty hearing with both ears, mild or severe pain in both ears, itchiness in the ears, and draining of fluid or pus from the ears.
This is an abnormal, noncancerous skin growth that develops in the middle ear behind the eardrum as a result of repeated middle ear infections.
Cholesteatoma starts as a sac or cyst that sheds layers of old skin. With time, these shed layers begin to accumulate and grow in size. As they grow in size, they begin to press against and destroy the middle ear’s delicate bones.
This damage to the middle ear structures results in hearing loss, loss of balance, and the malfunctioning of facial muscles.
4. Ruptured Eardrum
The eardrum, which is also known as the tympanic membrane, is a thin tissue that separates the ear canal from the middle ear. A tear or rupture in the eardrums can cause bilateral conductive hearing loss. This a hole or a tear in the eardrum; it is said to be ruptured or perforated.
A ruptured eardrum can be caused by; head trauma, foreign objects in the ear, exposure to loud noise, rapid pressure changes, and a middle ear infection.
Ruptured eardrums often heal on their own without treatment. But on some occasions, a surgical repair or a patch may be required to speed up the healing process.
5. Other Causes
Other causes of bilateral conductive hearing loss are; otosclerosis, microtia, middle ear infections, eustachian tube dysfunction, accumulation of fluid in the middle ear, head injuries, severe illnesses, and viral infections.
Bilateral Conductive Hearing Loss Symptoms
Bilateral conductive hearing loss can occur over time or suddenly, depending on the cause. For instance, sudden exposure to loud sounds can cause sudden bilateral conductive hearing loss, while earwax blockage can cause gradual hearing loss.
It is important to note that no two bilateral conductive hearing loss cases are the same, even if the causes are the same. As already stated, bilateral conductive hearing loss can be symmetrical or asymmetrical.
This means that if patient A has symmetrical bilateral hearing loss, he won't have the same symptoms as patient B, who has asymmetrical bilateral hearing loss.
Also, the effects of hearing loss on each hearing loss patient are unique. No two hearing loss patients have the same reaction to hearing loss. While some may be able to find ways to adjust to the loss of hearing, others may experience serious emotional and psychological disorders.
The symptoms of bilateral conductive hearing loss vary based on the root cause. This means that the symptoms a person with bilateral conductive hearing loss experiences are based on the cause of the hearing loss. If an ear infection causes hearing loss, the symptoms will be different from hearing loss caused by ruptured eardrums.
The difference in symptoms notwithstanding, there are some general symptoms that people with bilateral hearing loss share in common. These symptoms include the following:
1. Muffled Speech
Except for people with profound bilateral conductive hearing loss, the sound that most hearing loss patients hear is muffled.
This results from the poor conduction of sound from the outer and middle ear to the inner ear.
2. Difficulty Hearing in Noisy Environments
Most bilateral conductive hearing loss patients have difficulty hearing sound in noisy environments. They hear better during one on one conversations and in quiet environments. This mostly because the ear is unable to separate speech from background noise.
3. Feeling of Fullness in the Ears
Bilateral conductive hearing loss caused by fluid in the ear and eustachian tube dysfunction is often characterized by a feeling of fullness in both ears. This fullness in the ear may worsen in one ear, or the severity in both ears may be the same.
Tinnitus is the perception of noise in the ear when there is no external source of the noise. Tinnitus is a common symptom experienced by bilateral conductive hearing loss patients. Several reasons cause tinnitus. One of which is the absence of sound signals in the brain.
With no sound being sent into the inner ear from the outer and middle ear, the inner ear doesn't send any sound signal to the brain. In a bid to compensate for the lack of sound signals, the brain creates its sound. This sound is what is perceived as tinnitus noise in the ear.
Degrees of Bilateral Conductive Hearing Loss
Sound is measured in decibels. The normal range of hearing for adults is from zero to twenty decibels. This low range enables people with normal hearing to hear very faint sounds like human breathing, which is about 10 decibels.
This isn't the case for people with hearing loss. People with hearing loss are only able to hear sounds within a particular range; this range is above the normal level for normal hearing.
Bilateral conductive hearing loss is classified into four degrees. Hearing loss begins when a person is no longer able to hear sounds within the normal sound range.
Below are the different degrees of hearing loss and their characteristic symptoms:
1. Mild Bilateral Conductive Hearing Loss
People with mild bilateral conductive hearing loss can hear certain speech sounds but have difficulty hearing soft sounds. This includes sounds like dripping water, feet shuffling, whispered conversations, birds chirping, and leaves rustling.
There is also difficulty hearing sounds or speech from a distance and low-pitched or high-pitched sounds.
People with mild bilateral conductive hearing loss can hear and hold conversations in quiet environments. The best form of conversation for them is one on one conversations.
They, however, encounter difficulties hearing sounds when the environment is noisy or when the speaker is standing some distance away from them or not facing them. In this case, they may be able to hear the sound but unable to comprehend or understand what is being said.
2. Moderate Bilateral Conductive Hearing Loss
A person with moderate bilateral conductive hearing loss has difficulty hearing faint voices and whispers. There is also difficulty hearing speech or conversations at normal voice levels. In most cases, the speaker needs to talk above the hearing loss patient’s normal level to hear what is being said.
3. Severe Bilateral Conductive Hearing Loss
People who have severe bilateral conductive hearing loss are unable to hear speech being spoken at a normal level. Speech spoken at normal voice levels fades into whispers, and music is heard as a faint hum.
If the hearing loss is not sudden, at the initial stage, sounds may become muffled then gradually fade. Details of conversations also become fuzzy.
This makes the hearing loss patient constantly ask for amplification of volume and also repetition.
In the long run, the hearing loss patient may begin to withdraw from conversations and social activities because of the embarrassment associated with constantly asking for repetition and also the fear of misunderstanding conversations and giving the wrong answers to questions.
Asides from difficulty in hearing and understanding speech, depending on the cause, severe hearing loss can be accompanied by other symptoms. These symptoms include pain in the affected ears, feeling of fullness in both ears, dizziness, and tinnitus.
4. Profound Bilateral Conductive Hearing Loss
A person is said to have profound bilateral conductive hearing loss if he cannot hear sounds below 90 decibels in both ears. In some cases, people with profound hearing loss cannot hear anything at all, irrespective of the sound level.
This is the worst type of bilateral conductive hearing loss. Communication for people with profound bilateral conductive hearing loss is done by reading and writing, use of sign language, or lip reading.
Patients with this type of hearing loss can benefit from using hearing aids. Hearing aids for profound bilateral conductive hearing loss are known as power or superpower hearing aids. They are larger than regular hearing aids and are worn behind the ear with a custom earmold.
Bilateral conductive hearing can be very challenging because of the presence of hearing loss in both ears. This can have a toll on your life.
It is, therefore, necessary that you seek medical assistance.
If your emotional health and psychological health are being affected, your doctor may prescribe counseling sessions for you.
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