The local youth by and large have good hearing. However, they often do not pay attention to good hearing habits and hygiene. They tend to take their good hearing for granted and therefore choose not to protect their ears against possible threats to their hearing. The most common and prevalent threat would be that of listening to loud music for prolonged periods of time each day.
Nowadays, it is very common to see many youth with headphones or earphones in their ears during much of their non-schooling hours. The music that they listen to in these headphones and earphones may be set at very loud volumes. If the duration of exposure to this loud music and sounds is prolonged (up to 8 hours a day), then the inner ear will suffer from injury due to the loud noise. This is known as Noise Induced Hearing Loss.
These typically would affect the high frequencies of their hearing spectrum more than their low frequencies. This sometimes leads to inability to hear certain words clearly or sounds clearly.
Hearing loss can affect people of any age. Children can be born deaf, or develop hearing loss in their childhood. Hearing loss can affect both ears or just affect one ear. Hearing loss can be sudden in onset or it can develop slowly and progressively over many years. Persons of all age groups therefore can suffer from hearing loss at any point in their lives from many possible causes.
Hearing occurs when sounds in the environment get sensed by the hearing part of the brain. This pathway involves the following steps:
First, sound is transmitted as sound waves passing from the environment into the external ear canal. These sound waves then cause the eardrum and the middle ear bones to vibrate.
The vibrations are passed into the inner ear (cochlea) and move the inner and outer hair cells which regulate the endings of the hearing nerve and allow the hearing nerve to convert that vibration energy into electrical impulses that will pass along the hearing nerve (cochlear nerve).
The electrical impulses travel to the brainstem and up to the brain via a series of connections with other nerves within the central nervous system and eventually activate a certain portion of the brain that is responsible for hearing.
This is finally where the brain perceives the sounds and makes sense of the sounds coming from the environment.
Many problems can result in hearing loss. There may be conditions that prevent the sound waves from being transmitted effectively through the external ear canal or the middle ear.
Simple conditions like impacted ear wax acts as a plug that prevents the sound from passing to the eardrum. There may also be fluid that builds up in the space behind the ear drum that impairs the transmission of sound waves. This may be due to infections of the middle ear.
Other diseases cause the middle ear bones to become eroded and so they are not able to transmit the sound wave vibrations. There are also other diseases that affect the inner ear (cochlea). The most common is Presbycusis (old age hearing) which results when the cochlea starts to degenerate and the hair cells and nerve endings in the cochlea no longer work as well as when they were younger.
There could also be viral infections that also injure the inner ear and damage its ability to sense the sounds. There could also be tumours in the brainstem that press on the hearing nerve and prevent the nerve from functioning well.
As you can tell, there are a whole variety of reasons and conditions that result in hearing loss.
There are 3 main types or patterns of hearing loss.
Conductive Hearing Loss: Where there is a problem in the conduction and transmission of sound waves through the hearing system.
Sensorineural Hearing Loss: Where the problem lies in the cochlea (sense organ) or in the hearing nerve (cochlear nerve) or in the central nervous system. So there is a problem with either the conversion of the sound wave signal into electrical signals, or a problem with the transmission of these electrical signals to the brain.
Mixed Hearing Loss: This is basically a combination of both conductive hearing loss and sensorineural hearing loss.
Hearing loss is also graded into mild, moderate, severe and profound. This is determined by the minimum sound intensity which is needed before they are able to perceive sound. This can be plotted in a graphical manner in the hearing test called the Pure Tone Audiogram.
In this test, sounds of specific frequencies are presented to the patient/listener in a quiet environment. These sounds are of specific intensities and the minimum intensity (measured in decibels hearing level dBHL) that is needed before the patient identifies the sound is known as the hearing threshold. The plot of the hearing thresholds at each frequency (usually tested between 250Hz and 8000Hz) is known as the Pure Tone Audiogram.
Other more specialised hearing tests include the Speech Discrimination Score, which tests a listener's ability to repeat words that are spoken to him and is a measure of the accuracy of his hearing.
The first thing should be to consult with a specialist ENT surgeon. This will allow the surgeon to diagnose any correctable causes of hearing loss such as impacted ear wax, fluid in the middle ear etc.
Upon diagnosis of the underlying medical condition causing the hearing loss, these can potentially be treated in a variety of ways. In some situations like bad ear canal infections, antibiotic ear drops may be needed. Impacted ear wax has to be carefully removed. Fluid in the middle ear has to be drained. If there are specific diseases like cholesteatoma which erodes the middle ear bones, these have to be operated on.
Lastly, there is the option of hearing aids and surgical hearing implants to help those where there is no medically treatable disease.
Conventional hearing aids are extremely useful in helping patients with hearing loss restore their hearing. These miniature hearing aids basically collect the sounds from the speakers and the environment and present them at much louder volumes (amplifies the sounds) in the ear canal so that there are much stronger sound waves travelling through the hearing system and enables those with hearing loss to hear these normal volume sounds because they are finally presented to the ear canals in much louder volumes.
Wearing hearing aids enables the user to hear much better. This leads to ease of communication. Oftentimes, poor hearing leads to poor communication and there can be misunderstandings. The hearing loss patient also struggles with social interactions and therefore may choose not to attend social functions or interact with others. This leads to isolation and loneliness and oftentimes depression. Restoring one's hearing allows them to communicate easily again and therefore avoids these problems. Also, as they continue to engage the people and environment around them by listening better, studies have shown that they delay the onset of dementia as well.
The cons of wearing hearing aids is that it is a digital device so it can also break down and have performance issues. Sometimes, there is the acoustic feedback which results in a high pitched "eeeee" sound coming from the hearing aid. Other problems include the difficulty of operating the small buttons on these hearing aids.
However, with many hearing aids nowadays being wirelessly compatible with smartphones, programming the hearing aids on the phone is much easier rather than pressing small buttons on the hearing aid. Batteries have also become rechargeable which negates the need to insert and withdraw small batteries. The few cons of hearing aids are being eliminated by better design and technology.
Family can help by encouraging patients with hearing loss to seek consultation and treatment early. Oftentimes, it is the family that is facing communication problems that feels very frustrated compared to the patient as the patient may just accept his hearing loss and cope by withdrawing from social interactions.
Families can also help with old persons who may have difficulties taking care of their small hearing aids and programming their hearing aids. They can also remind each other about good listening habits like not listening to music at too loud volumes.
The 3 main myths of hearing aids are:
- Hearing aids will overload my hearing and cause my hearing to worsen
- Hearing aids don't work because they have problems with distorted sounds or acoustic feedback (the loud "eeee" sound)
- Hearing aids are only for old people. (Anyone can use hearing aids)
The best way is to consult an audiologist who specialises in dispensing and prescribing the correct type and model of hearing aid for your needs. He or she will have to recommend based on your pattern and grade of hearing loss.
At the same time, patients should tell the audiologist their main types of environments where communication is a problem so that they can program the hearing aid appropriately. There are many different models ranging from tiny hearing aids that are almost "invisible" as they are plugged into the ear canals and there are other models which generate more powerful sounds and can be worn behind the ears.
There is a large range in pricing for hearing aids ranging from $1500 for a simple hearing aid, to about $6000 for a very sophisticated one. There are currently subsidies available to elderly patients who are Singaporean and above 60 years of age. They must fulfil some financial means testing to determine the level of subsidies they can receive. These subsidies are currently available only if you purchase them from the government restructured hospitals.