"Hearing loss can be a progressive condition, but it has lasting and sometimes devastating effects. In some studies, people have reported that hearing loss is worse than vision loss due to the isolation it causes. Many forms of hearing loss are reversible, while others are not. It's important to consult your doctor to determine the best course of action for your particular situation." - Drew Sutton, MD, Board-Certified Otolaryngologist
Hearing loss affects many people, but it manifests a little differently in each person. For some, it develops slowly over time until it becomes a real difficulty hearing. For others, this process seems to happen in a few days and reduces hearing acuity.
When hearing loss occurs, the first question people ask is whether it is reversible. The answer is more nuanced than a simple yes or no, as there are many forms of hearing impairment that can reduce your ability to understand others and hear fully.
Here's an overview of the different ways hearing can deteriorate and the treatment options. Understanding these mechanisms and existing solutions can be helpful for your own form of hearing loss.
Conductive Hearing Loss
Conductive hearing loss corresponds to a reduced ability of the ears to perceive sounds from the immediate environment. It is related to a problem located in the outer or middle ear: auricle, ear canal, eardrum, ossicles, Eustachian tubes, and middle ear cavity.
Compared to other forms, conductive hearing loss generally responds better to treatment and can even be completely reversible in some cases. Here's an overview of its causes and treatments.
Causes of Conductive Hearing Loss
Conductive hearing loss can have several origins. In practice, anything that disrupts the transmission of sound wave energy to the eardrum and ossicles can contribute to it. Here are the possible causes, from the most external to the most internal.
The first possible cause is earwax impaction. Earwax is a naturally secreted wax that helps protect the ear canal. Sticky, antibacterial, and antifungal, it plays an important role in protecting the ears. Under normal circumstances, actions like chewing naturally move old earwax outwards, while new earwax is produced.
In cases of impaction, earwax accumulates until it obstructs the ear canal, dulling sounds, much like earplugs would.
The next cause, moving further into the ear, concerns the tympanic membrane, or eardrum. The eardrum is a thin membrane that moves according to pressure differences created by sound. It separates the outer ear from the middle ear and has air-filled spaces on both sides.
A common problem is a pressure imbalance between the outer and middle ear. You have probably experienced this form of hearing loss on an airplane. Before your ears pop, you notice that your hearing is muffled. This sensation comes from a pressure difference that stretches the eardrum on the side where the pressure is strongest, reducing its ability to vibrate with sound.
Another possible problem is a perforated eardrum, when a hole forms in the membrane. Without a seal, hearing decreases.
Finally, conductive hearing loss can originate in the middle ear. Three small bones connected to the eardrum transmit the membrane's movement to the cochlea in the inner ear. These ossicles occupy a space between the eardrum and the cochlea, called the middle ear cavity.
One of the most frequent causes of middle ear hearing loss is fluid accumulation in the middle ear cavity. Fluid conducts sound very differently from air, and this accumulation can significantly reduce hearing. The Eustachian tube is responsible for draining this cavity, but it can become blocked for many reasons, including an upper respiratory infection or overgrown adenoids.
Treatments for Conductive Hearing Loss
A large number of conductive hearing losses respond well to treatment. These vary in cost and complexity, but overall this form is the most responsive to treatment and can, in some cases, provide immediate relief and completely reverse hearing loss.
Hearing losses due to the outer ear and ear canal are most likely to disappear completely after treatment. For earwax impaction, the best solution is professional earwax removal by a trained healthcare provider. Once the impaction is removed, hearing usually returns to normal.
Eardrum problems are a little more complex, but they remain largely treatable. When the eardrum suffers from a pressure imbalance, the main treatment involves restoring that balance.
In cases of tympanic perforation, healing usually occurs on its own within three months, but surgery is sometimes necessary. These lesions can lead to permanent hearing loss, although most people recover completely. In some cases, skin from the ear canal can pass through the eardrum hole and form a skin cyst called a cholesteatoma, leading to other complications such as infections and hearing loss. Cholesteatomas must be surgically removed.
The last possible cause, fluid accumulation in the middle ear, also responds well to treatment. This condition, called otitis media with effusion, can be due to an underlying infection or simply occur due to Eustachian tube obstruction. A course of antibiotics and, possibly, decongestants often resolve the problem and completely reverse hearing loss.
Sensorineural Hearing Loss
Sensorineural hearing loss differs from conductive hearing loss in that it concerns the conversion of physical sound into nerve impulses. It responds much less well to treatment and more often results in permanent hearing loss.
Here's an overview of its common causes, how to prevent it, and how it is managed.
Causes of Sensorineural Hearing Loss
Sensorineural hearing loss is related to the inner ear and the auditory nerve. Many factors can damage it: medications, exposure to loud noises, genetics, etc.
One possible cause is taking medications known for their ototoxicity. These medications are called ototoxic, meaning they are potentially harmful to the ears. There are more than 200 of them.
If you are taking a medication that lists hearing loss among its side effects, strictly follow the prescription and remain attentive to any changes in your hearing, to detect any lasting effects as early as possible.
Another possible cause is exposure to loud noises. The cochlea is an extremely sensitive organ, capable of distinguishing tiny differences between sounds and offering you very fine sound resolution. Loud sounds can damage this delicate mechanism and cause irreversible hearing loss.
Sounds below 70 decibels are generally considered safe; beyond that, each increase in sound level increases the risk of hearing loss. Limiting your exposure to noise is an excellent way to reduce the risk of developing mild sensorineural hearing loss later in life.
Treatment of Sensorineural Hearing Loss
Sensorineural hearing loss is generally not reversible: it is the most permanent aspect of hearing loss. Most treatments aim to alleviate symptoms and restore some hearing, even if it is not quite as it was before.
The main treatment relies on hearing aids. These are assistive devices that are placed in the ears. Once in place, the hearing aid picks up the sounds you would normally hear and amplifies them.
This is done using a built-in microphone that picks up sound stimuli, an amplifier that increases the sound intensity, and a speaker that delivers a louder version of the original sound to the ear. With louder sounds, one hears and understands much better.
Conclusion
In summary, hearing loss is indeed reversible in some cases, while it is permanent in others. Conductive hearing loss concerns the outer and middle ear: this is the form that responds best to treatment. Conversely, sensorineural hearing loss tends to be lasting and there is virtually no way to reverse it.
Sources:
Antibacterial and antifungal properties of human cerumen | NCBI
Ototoxic Medications (Medication Effects) | ASHA
Otitis Media (Middle Ear Infection) in Adults | Columbia University Medical Center Department of Otolaryngology Head and Neck Surgery
