Conductive hearing loss is caused by blockage or damage in your outer ear, ear canal, or middle ear, making it difficult for sounds to pass from your outer ear to your middle ear.
Conductive hearing loss is less common, affecting only 10% of all hearing loss.
Have you ever had the sensation that your ears are clogged during a flight? It can be uncomfortable, and sometimes even painful, and cause your hearing to become muffled and feel like you are wearing earplugs. This could be conductive hearing loss.
It happens as a result of a sudden change in air pressure and puts pressure on your middle ear and Eustachian tubes. These tubes are canals on each side of your face that run from the back of your nose and upper throat to your middle ear. It’s this Eustachian tube dysfunction that is likely to have caused your reduced hearing during your flight.
Conductive hearing can happen in one or both ears and it occurs when there is a blockage in the outer or middle ear that stops sound from passing through to the inner ear properly. It is less common than sensorineural hearing loss, making up just 10% of all cases of hearing loss.
Your ear anatomy is made up of two crucial elements:
The role of your outer ear is to direct sounds to your eardrum (tympanic membrane). These sounds are then passed on as vibrations through the middle ear via the small ear bones until they reach the inner ear (cochlea). You experience conductive hearing loss when these sounds cannot pass from the outer ear to your middle ear.
The key difference between conductive and sensorineural hearing loss is that it affects different parts of your ear. Sensorineural hearing loss occurs when there has been damage to the sensory part of the ear, located in the inner ear, which is where sound waves are transmitted to the brain.
Conductive hearing loss is often mild to moderate and makes sounds appear softer, but with the aid of amplification, they can be heard much more clearly. When you have conductive hearing loss you may notice that your hearing has improved in noisy surroundings. This happens because conductive hearing loss reduces the level of background noise that would normally stop you from being able to hear conversations.
Just as if you covered your ears or wore earplugs, conductive hearing loss affects the way you perceive sound levels. You may find everything sounds either muffled or just much quieter than you are used to. Other symptoms of conductive hearing loss include:
You will likely find that while speech still sounds clear with no distortion, you need it to be louder for you to be able to hear properly.
There are many causes linked with conductive hearing loss which can affect the ear canal and outer and middle ear. These may include:
This happens when there is a build-up of earwax (or cerumen) in the ear which can sometimes be made worse if you have tried to dislodge the earwax yourself by inserting something such as a cotton swab into the ear. Excess wax can stop sound from being able to travel from your outer ear to reach your inner ear.
Outer ear infection
Otitis externa is when the skin of the external ear canal is infected and happens when debris and swelling have blocked the canal.
Squamous cell carcinoma
Most cases of squamous cell carcinomas of the temporal bone affect adults in their 50s and 60s. It’s the most common cancer of the external ear canal that causes discharge from the ear, earache, bleeding and conductive hearing loss.
Blocked Eustachian tube
The Eustachian tube connects the back of the nose to the middle ear but if the lining of the mucosal tube becomes swollen or the tube doesn’t open or close correctly it can cause Eustachian tube dysfunction. This is often experienced when you fly, have a head cold or swimmer’s ear (fluid in the ear).
Trauma or infection can create a hole in the eardrum and affect hearing. It can happen as a result of changes in air pressure (barotrauma) during a flight or when scuba diving.
Inflammation can affect your middle ear, causing conductive hearing loss. Chronic suppurative otitis media is a persistent ear infection that can tear or perforate the eardrum. Otitis media with effusion (fluid in the middle ear) is frequently linked with hearing loss, earache, tinnitus (ringing in the ears) and vertigo. Otitis is more common in adults who have a weakened immune system.
This is a rare abnormal growth of one of the small bones of the middle ear (stapes bone) and will stop the structures of the ear being able to function properly. Cases of otosclerosis are considered to be hormonal, inflammatory (such as the measles virus and autoimmune processes), genetic and metabolic. It mainly affects people aged between 15 and 40 and is more likely to be experienced by women than men. Around 20% of incidences of conductive hearing loss are linked to otosclerosis.
These abnormal and noncancerous skin growths are commonly associated with ear infections. They can develop behind the eardrum in your middle ear. They are often a cyst or sac and as the size of the growth increases, it can cause damage to the delicate bones of your middle ear.
This is the second most common tumor of the temporal bone and the most common primary neoplasm (new and abnormal growth of tissue) of the middle ear. It mainly affects women in their 50s and 60s and with tinnitus (ringing in the ears), the growth in the middle ear stops sound waves passing through the ear resulting in conductive hearing loss.
Temporal bone trauma
A blunt head injury can injure the brain, facial nerves and inner ear while also damaging the eardrum and middle ear. For people who remain conscious after such an injury, hearing loss will be immediately evident. Around 40% of people experience tinnitus and hearing loss after a head injury.
Due to the number of different potential causes, conductive hearing loss might be diagnosed by either your doctor or hearing care professional. They will ask you about your symptoms and your medical history. They will also examine your ears to look for signs of damage, infection or blockage. Several tests can be used to diagnosed conductive hearing tests and identify the underlying causes:
This is a common test for conductive hearing loss where your doctor will insert an otoscope into your ear to examine your ear canal and eardrum. This will show if you have injured your eardrum or there are any foreign bodies in your ear canal such as impacted earwax or an issue with the middle ear. Your doctor will also look at the color of the eardrum, its translucency and position.
This test uses a tuning fork which is struck and then put on the crown of your head. You will need to say whether the sound is louder in your left ear, right ear or the middle. If you have normal, unaffected hearing, then you should be able to pick up the sound equally in both ears. If you have conductive hearing loss, then you will likely hear the sound louder in the affected ear.
A probe is put in your ear to check whether there is growth, abnormal pressure or scarring or perforation to your eardrum. The test only takes a couple of minutes, but you won’t be able to speak, swallow or move while it’s being carried out.
This test will assess your hearing threshold to enable your doctor to determine if your hearing levels are within the normal limits for healthy hearing.
Most incidences of conductive hearing loss are temporary and will either self-resolve or can be dealt with by treating the underlying cause. For instance:
Warm-water irrigation is a safe and gentle way to remove impacted earwax. It should be performed by your doctor or hearing care professional but should be avoided if you have previously had surgery on your ear, ear infections in the past or a perforated eardrum.
Outer ear infection
The damaged tissue is removed from the ear before applying ear drops. If the infection is severe then a wick can be put in the ear for two or three days to help ensure the medication is effectively delivered to the affected area. Oral antibiotics may also be prescribed.
If you ensure you keep your ear canal clean, the hole should heal by itself. However, if an infection develops, you may need to be prescribed oral medication or antibiotic ear drops to treat the infection. If your eardrum doesn’t heal within two months, you may need a tympanoplasty. This surgery uses grafts to repair the perforation.
Myringotomy is a surgical incision into the eardrum to release fluid and relieve pressure in the ear. This allows sound waves to reach the inner ear. The fluid is suction from the middle ear through the incision. A sample of the fluid may be sent to a lab to determine if there is a virus or bacteria present. Ventilation tubes are sometimes used to allow the incised eardrum to stay open to allow the fluid to drain more effectively.
It's time to finally treat your hearing loss. Sign up for a free consultation with a licensed hearing care professional today to determine if you have hearing loss. It’s the start of your journey towards better hearing.