We often talk about hearing loss caused from noise-exposure and aging because these are two of the most common causes of hearing loss. But the reality is, there are many different causes of hearing loss as well as different types of hearing loss.
SENSORINEURAL HEARING LOSS:
Sensorineural hearing loss is the most common type of hearing loss we see in our clinics. Both aging and noise-exposure can lead to sensorineural hearing loss. This type of hearing loss is caused from damage to the organ of hearing called the cochlea. Tiny hair cells inside the cochlea become damaged or die with age or when exposed to dangerously loud sounds. With sensorineural hearing loss, the nerve that connects the inner ear to the brain (called the 8th cranial nerve) can be damaged as well.
Typically, this type of damage occurs gradually over a long period of time in one’s lifetime. Because this is such a gradual process, our brain adapts to this slow decline in hearing. Many people with sensorineural hearing loss don’t realize the extent of their hearing loss until they are fit with hearing aids!
There are many other causes of sensorineural hearing loss as well which include:
Genetics: Sometimes, sensorineural hearing loss runs in families. Genetic hearing loss is congenital and is either discovered at birth or can take longer to develop and is discovered later in life. There are also many different syndromes that can cause genetic hearing loss.
Certain systemic, neurological or autoimmune diseases: diabetes, Meniere’s disease, lupus
Viral and bacterial infections: Measles, mumps, meningitis, syphilis, toxoplasmosis
Cardiovascular disease: heart attack, stroke, arrhythmia, and heart valve problems
Medications: Some medications can cause sensorineural hearing loss, which can be temporary or permanent. Any medication that causes sensorineural hearing loss is called ototoxic, which literally means toxic to the ear. The most common ototoxic medications are:
- Certain antibiotics
- Loop diuretics (water pills)
- Chemotherapy medications (cisplatin & carboplatin)
For a full comprehensive list of ototoxic medications click here.
(Important note: Do NOT stop taking any medications without first consulting with your doctor!)
While we can’t control our genes, nor can we prevent certain chronic medical issues listed above, we can prevent sensorineural hearing loss caused from excessive noise exposure. (Click here to read our blog on noise-induced hearing loss and how to prevent it).
While there is currently no cure for sensorineural hearing loss, the vast majority of patients with sensorineural hearing loss benefit greatly from wearing properly fitted hearing aids.
CONDUCTIVE HEARING LOSS:
Conductive hearing loss is caused by a “mechanical problem” somewhere along the hearing pathway. It happens when sound cannot properly travel to the inner ear and up to the brain where sound is processed. Unlike sensorineural hearing loss, conductive hearing loss can be temporary, or treated with surgery.
Some common types of conductive hearing loss include:
- Fluid in the middle ear which can be caused by a cold or allergies
- Ear infections
- Earwax build-up
- Perforated eardrum
- Head trauma
- Issues with the Eustachian tube (the tube that connects the middle ear to the back of the throat)
- Benign tumours of the ear
- Growths in the ear canal or middle ear (cholesteatoma)
- Malformation of the ear
- Abnormal bone growth in the middle ear (otosclerosis)
Click here for more information on the different parts of the ear!
If during a hearing test, your audiologist notices you have conductive hearing loss, he or she will make a referral so you can be seen by an ENT physician (ears, nose & throat specialist) as in order to be fit with hearing aids, medical clearance from an ENT will be needed.
Depending on the cause of the conductive hearing loss, surgery or medical treatment may be the best treatment option and you may not need hearing aids. Sometimes, patients who are candidates for surgery decide to opt out of it and choose hearing aids instead if they do not want to go through an invasive surgery.
MIXED HEARING LOSS:
Sometimes, sensorineural hearing loss and conductive hearing loss happen at the same time. When this happens, we call this mixed hearing loss. Any combination of the above causes of both sensorineural hearing loss and conductive hearing loss can cause mixed hearing loss. Just like with sensorineural hearing loss, when mixed hearing loss is identified, medical clearance from an ENT physician is needed before being treated with hearing aids.
CENTRAL HEARING LOSS
Central hearing loss happens when there is a problem with the nerve that connects the inner ear to the brain. When someone has central hearing loss, their outer, middle and inner ear may be working just fine, but their brain is not able to properly make sense of the sounds being heard.
Central auditory processing disorder (called CAPD for short) is one of the most common forms of central hearing loss where there is a disconnect between what is heard and what is understood.
People with CAPD often find they have trouble understanding conversations in noisy environments and difficulty localizing where sound is coming from. There is some research to suggest that hearing aids can help treat central auditory processing disorder and other causes of central hearing loss.
Call our clinics today to schedule a full hearing test! If a hearing loss is identified, your audiologist will also be able to tell you:
- The type of hearing loss
- The severity of the hearing loss
- Treatment recommendations
Sackville Hearing Centre: 902-865-4455
Alderney Hearing Centre: 902-465-4334