Types of hearing loss
The type of hearing loss you have depends on what part of your hearing is damaged. There are three main types of hearing loss:
- Conductive hearing loss
- Sensorineural hearing loss
- Mixed hearing loss
Conductive hearing loss
Conductive hearing loss occurs when sound waves are prevented from passing from the outer ear and middle ear into the inner ear, specifically the cochlea. This type of hearing loss commonly happens when the outer or middle ear is damaged. Fluid buildup in the middle ear caused by colds or upper respiratory tract infections will cause temporary hearing loss. In this case, hearing loss is usually reversible and can be treated. However, a chronic ear infection (otitis media) is mostly irreversible and can cause permanent damage to the affected ear.
Symptoms of hearing loss can be mild, moderate, severe, or profound. Hearing loss can affect one ear (unilateral) or both ears (bilateral). If hearing loss between the ears is significantly different, then it is labeled as asymmetric hearing loss.
One of the common causes of conductive hearing loss is earwax buildup in the ear canal. When earwax blocks the ear, sound waves are prevented from passing from the outer ear and middle ear into the inner ear, which results in ear damage. Other causes often associated with conductive hearing loss include infection of the ear canal or middle ear, perforated eardrums, or abnormal growth of bone in the middle ear (otosclerosis – a hereditary disorder).
In general, conductive hearing loss can be both temporary or permanent. In most cases, hearing loss is treatable with proper medical treatment and surgery. In cases where medical treatment does not help, hearing aids or implants are recommended.
Sensorineural hearing loss
Sensorineural hearing loss is the hearing loss caused by damage to the tiny hair cells in the inner ear or the hearing nerve.
For example, if it’s hard to hear voices in places with a lot of background noise or if it’s challenging to understand children’s voices, it’s most likely sensorineural hearing loss. Typically, sensorineural hearing loss develops gradually and becomes worse with time.
Sensorineural hearing loss is the most common of the three types of hearing loss. In contrast to conductive hearing loss, sensorineural hearing loss is permanent, and often the result of aging, exposure to loud noise, medication, and genetics. This type of hearing loss is prevalent in older adults as a part of the natural aging process. It’s known as presbyacusis or age-related hearing loss. Hearing loss typically progresses slowly but persistently, starting at age 60 and affects both ears (bilateral).
Prolonged exposure to loud noise has become an increasingly frequent cause of sensorineural hearing loss. The additional causes are often associated with Ménière’s disease, which causes dizziness, tinnitus, and, ultimately, hearing loss.
Unfortunately, there is no medical treatment for sensorineural hearing loss as the hair cells in the inner ear cannot be repaired or replaced. Luckily, people with sensorineural hearing loss can benefit from hearing aids or cochlear implants.
Mixed hearing loss
Mixed hearing loss is a combination of conductive and sensorineural hearing loss that occurs at the same time. With mixed hearing loss, the damage is present in both the outer or middle ear and the inner ear (cochlea). The sounds can be both softer in volume and more difficult to understand. For example, if a person has a noise-relayed impairment and a perforated eardrum, then hearing impairment is dubbed as “mixed hearing loss”. The condition can cause mild, moderate, or severe hearing loss.
Causes of mixed hearing loss include those related to sensorineural hearing loss, such as noise, age, medication, and heredity. Factors that cause conductive hearing loss, and can also bring on mixed hearing loss, include ear wax, ear infections, perforated eardrums, and otosclerosis. The treatment for mixed hearing loss involves a combination of medical or surgical treatment and the use of hearing aids or cochlear implants.
No matter which type of hearing loss you have, it’s important to treat it early on to prevent further auditory damage and well as other health-related consequences. It’s best to assess your hearing for free at an audiologist at one of our partner clinics near you, even if you’re slightly unsure about your auditory health.