Hearing loss or hearing impairment is defined as a partial or complete inability to hear. People who have chronic ear infections mostly develop hearing loss. However, the condition can also be caused by several reasons such as aging, heredity, noise pollution, and certain diseases or disorders. One or both ears can be impaired.
Hearing loss is also observed in other conditions caused by the intake of ototoxic (ear-damaging) medications, tumors, and head injuries.
In medical science, hearing loss is categorized into three types. They are:
- Conductive hearing loss
- Sensorineural hearing loss (SNHL)
- Mixed hearing loss
1. Conductive Hearing Loss
This type of hearing loss occurs when there is an ear damage, specifically in the ear canal, eardrum, and middle ear that contains the ossicles or tiny bones: incus, malleus, and stapes.
Causes of Conductive Hearing Loss
- deformities in the eardrum, ear canal, or middle ear structures
- fluid accumulation in the middle ear
- ear infections
- accumulation of earwax
- accumulation of grime in the ear canal
- hole or tear in the eardrum
- insertion of external objects in the ear
- unusual growth of a bone in the middle ear (also termed as otosclerosis)
There are also some causes that are not so frequently observed, such as failure of the ear canal to open during childbirth, the absence of an ear canal, or a dysfunction in the middle ear structures.
Treatment of Conductive Hearing Loss
The abnormalities mentioned above are possible to be surgically corrected. People who have hearing problems can improve their hearing by amplification if in case their surgeries fail to treat the problem. One can do this by using a bone conduction hearing aid or by using hearing devices that will be implanted in the ear by a doctor or a medical professional.
Hearing loss can also be due to infections, tumors, or an accumulation of ear fluid. The infections can be treated using antifungal or antibiotic medications. For tumors and accumulated fluid in the middle ear, surgery is required. If the basic surgery does not help, then antibiotic medication is recommended.
In cases where patients have a head trauma or head injury, certain surgical repairs can be done after the patients are stabilized from the traumatic injury.
Another form of conductive hearing loss is otosclerosis. In this condition, hearing loss can happen when there is an overgrowth of the middle ear bones. An excessive growth of the bones can interfere with sound transmission. Moreover, this condition occurs when where there is a fixation or immobility in the tiny bone called stapes. If the stapes gets immobile, then the sound would not be able to reach the middle ear, thereby causing hearing loss. Surgical repair can be done for this condition where the immobile stapes are replaced by mobile prosthesis. The fixation of stapes can also be caused by the measles virus. However, there has been a decrease in otosclerosis due to the availability of measles vaccination and global awareness of the disease.
Otosclerosis may also lead to another type of hearing loss called as the sensorineural hearing loss.
2. Sensorineural Hearing Loss
Sensorineural hearing loss is a type of hearing disorder, which is caused by a damage to the nerve cells or fibers of the cochlea or inner ear.
Causes of Sensorineural Hearing Loss
- viral infections
- certain diseases
- head trauma
- genetic hearing loss
- malformation of the inner ear
- Meniere’s disease
Meniere’s disease, also known as vertigo, is a condition in which people feel like they are spinning and feeling that there is an immense pressure inside their eardrum leading to other symptoms such as ringing in the ears and hearing loss that might become permanent.
Treatment of Sensorineural Hearing Loss
- Acoustic trauma is a hearing loss due to being exposed to extremely loud noises for a prolonged period of time. It can be cured by medical therapy. Medical therapy includes corticosteroids that help in reducing cochlear hair cell inflammation and help in restoring the damaged ear structures.
- Hearing loss may also occur after a person has recently had a head trauma. It is also caused by a sudden change in air pressure (like an airplane descent). The changes in air pressure can cause the ear's inner fluid compartment to rupture, causing inner ear toxicity.
- Meniere’s disease is a disorder where you initially have a spinning sensation. This condition is also termed as vertigo. The disease is also accompanied by symptoms such as a feeling of some pressure in the ears, ringing in the ear (also called as tinnitus), and above all, a fluctuating hearing loss that further advances and results in a permanent hearing loss. A low-sodium diet, taking diuretics, and corticosteroids are used to manage Meniere’s disease. If one's vertigo cannot be relieved by medications, certain surgical procedures can be performed instead.
- Hearing loss that is caused by tumors in the balance nerve cannot be treated with irradiation. In such diagnosed cases, 50 percent of people get half of their hearing back after a hearing preservation surgery for tumor removal.
- Hearing loss that is caused by some other diseases that people have in their central nervous system can be treated and can be medically managed.
- The irreversible sensorineural hearing loss is the most common problem today when it comes to losing one's hearing. The condition can be managed by using a number of hearing aids available these days. If using those primary hearing aids does not turn out to be fruitful then cochlear implants are always an option for such disorders.
3. Mixed Hearing Loss
When a person has both conductive as well as sensorineural hearing loss, the condition is called as a mixed hearing loss. Since both the inner and the outer part of the ear are affected, it also suggests damage to both parts of the ear. The severity of a mixed hearing loss can range from mild to increasingly high.
Treatment of Mixed Hearing Loss
Experts recommend that introducing a conductive hearing component to the ear can somewhat justify the treatment for mixed hearing loss. However, for a long-term diagnosis, a strict medical treatment is essential.