What are the types of hearing loss?
There are many different kinds of hearing loss. However, no hearing loss is considered a “normal” part of health and should be taken very seriously. People can have different types of hearing losses in each ear or each ear can be working the same. If someone suspects their ears are working differently, it is very important to follow up with their ear, nose, and throat physician. Please read on to find out more about the different types of hearing loss. The type of hearing loss you have usually is related to the problem area in the anatomy of the ear (inner, middle, or outer ear), as well as by its severity.
1. Sensorineural Hearing Loss
This is a hearing loss which originates in the inner ear. This can either be within the organ of hearing, the cochlea, or with the nerve fibers that run from the inner ear up to the brain. The cochlea is a small snail shaped organ which houses three chambers of fluid which are unique to the ear along with little cells called hair cells. When someone has a sensorineural hearing loss, often it is due to damage to any of these structures within the cochlea or between the synapse of the hair cells and the auditory nerve.
A sudden idiopathic sensorineural hearing loss is when someone experiences a sudden drop in hearing that does not return within a few minutes with no obvious reason why. THIS IS AN EMERGENCY! Time is of the essence when this happens. There is a very short period of time, typically no more than 3 days, in which this type of hearing loss has a possibility of being reversed. The sooner an ear, nose, and throat specialists can provide treatment, the better chance a patient has to recover this lost hearing.
b. Noise induced sensorineural hearing loss (NISNHL): Just as the name implies, this is a hearing loss due to noise exposure. This noise exposure does not have to be a recent event to result in this type of hearing loss. All it takes is one blast, or an extended time of being exposed to a loud noise to result in a noise-induced hearing loss. This is the one type of hearing loss which can be prevented so it is extremely important to wear hearing protection while around loud sounds. When someone has a noise-induced hearing loss the little hair cells within that person’s cochlea have been damaged to the point that they cannot recover. The stereocilia (or little hairs) have become all tangled or are quite literally blown away in the areas on the cochlea of hearing loss.
c. Temporary thresholds shift (TTS): Have you ever gone to a concert and then come home and felt like you had cotton in your ears to wake up the next morning to normal hearing again? This is a temporary threshold shift. During the time that you were exposed to a lot of noise, like a concert, the little hairs in the cochlea became overwhelmed and experienced some damage. In the time that these cells are resetting people can experience a temporary hearing loss. However, just because this is a temporary hearing loss doesn’t mean people should ignore it. When this happens, we have done a significant amount of damage to our ears which will come back to haunt us in our future!
2. Conductive Hearing Loss
Conductive hearing loss: When someone has a conductive loss, the inner ear and nerve are working how they should work but the person is still experiencing a decrease of hearing. This is because there is something, either in the outer ear or middle ear which is preventing the eardrum and bones in the ear from vibrating like they should. Some examples of what may cause a conductive hearing loss include: earwax completely blocking the ear canal or resting on the ear drum, ear infections, perforated eardrums, trauma, fluid within the middle ear, or any disease of the outer and middle ear. If someone has a conductive loss, it is very important to see their ear, nose, and throat physician to discuss medical treatment for this hearing loss. Sometimes this type of hearing loss can be reversed!
3. Mixed Hearing loss
Mixed hearing loss: Simply put, this is when there is a conductive hearing loss (affecting the outer/middle ear) in addition to a sensorineural hearing loss (affecting the inner ear/nerve). Just like with a conductive loss, it is very important to follow up with a physician when a mixed hearing loss is found. Often, this is a sign of another pathology which needs to be addressed.