What is a Common Problem of the Youth?
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 from potential threats. The most common threat is listening to loud music for prolonged periods each day.
Nowadays, it is very common to see many young people wearing headphones or earphones during much of their non-school hours. The music they listen to through these headphones and earphones may be set at very high volumes. If exposure to this loud music and sounds is prolonged (up to 8 hours a day), the inner ear will be injured by the noise. This is known as Noise-Induced Hearing Loss.
These would typically affect the high frequencies of their hearing range more than the low frequencies. This sometimes leads to an inability to hear certain words or sounds clearly.
Do Only Old People Get Hearing Loss?
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 one ear. Hearing loss can be sudden in onset or 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 are detected by the auditory system. 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 then up to the brain via a series of connections with other nerves within the central nervous system, eventually activating a specific portion of the brain responsible for hearing.
This is finally where the brain perceives the sounds and makes sense of the sounds coming from the environment.
What Could Cause Hearing Loss?
Many factors can cause 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 earwax act as a plug that prevents sound from reaching the eardrum. There may also be fluid that builds up in the space behind the eardrum that impairs the transmission of sound waves. This may be due to middle ear infections.
Other diseases cause the middle ear bones to erode, so they are unable to transmit 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 begins to degenerate, and the hair cells and nerve endings no longer function as well as they did when the person was younger.
There could also be viral infections that injure the inner ear and damage its ability to sense sounds. There could also be tumours in the brainstem that press on the hearing nerve, preventing it from functioning properly.
As you can tell, there is a wide variety of reasons and conditions that can result in hearing loss.
How Many Types of Hearing Loss Are There?
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), in the hearing nerve (cochlear nerve), or in the central nervous system. So there is a problem either with converting the sound wave signal into electrical signals or with transmitting these electrical signals to the brain.
Mixed Hearing Loss: This is a combination of conductive and sensorineural hearing loss.
Hearing loss is also graded into mild, moderate, severe and profound. This is determined by the minimum sound intensity required for them to perceive sound. This can be plotted on a graph 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 have specific intensities, and the minimum intensity (measured in decibels hearing level, dB HL) required 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 spoken to him and measures the accuracy of his hearing.
What Should One Do if They Have Hearing Loss?
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 earwax or fluid in the middle ear.
Once the underlying medical condition causing the hearing loss is diagnosed, it can potentially be treated in a variety of ways. In some situations, such as severe ear canal infections, antibiotic ear drops may be needed. Impacted earwax has to be carefully removed. Fluid in the middle ear has to be drained. If there are specific diseases, such as cholesteatoma, that erode the middle ear bones, they have to be operated on.
Lastly, there are hearing aids and surgical hearing implants to help those for whom there is no medically treatable disease.
What Are the Pros & Cons of Hearing Aids?
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 (amplifying the sounds) in the ear canal, so that there are much stronger sound waves travelling through the hearing system, enabling 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. Often, poor hearing leads to poor communication and misunderstandings. The hearing-loss patient also struggles with social interactions and may therefore 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 with the people and environment around them by listening better, studies have shown that they delay the onset of dementia.
The cons of wearing hearing aids are that they are digital devices, so they can also break down and have performance issues. Sometimes there is acoustic feedback, resulting in a high-pitched “eeeee” sound from the hearing aid. Other problems include the difficulty of operating the small buttons on these hearing aids.
However, with many hearing aids now wirelessly compatible with smartphones, programming them on the phone is much easier than pressing small buttons on the hearing aids. Batteries have also become rechargeable, eliminating the need to insert and remove small batteries. The few cons of hearing aids are being eliminated by better design and technology.
How Can Family Help?
Family can help by encouraging patients with hearing loss to seek early consultation and treatment. Often, it is the family facing communication problems who feel very frustrated, compared to the patient, as the patient may simply accept his hearing loss and cope by withdrawing from social interactions.
Families can also help with older persons who may have difficulties taking care of their small hearing aids and programming them. They can also remind each other about good listening habits, like not listening to music at too high a volume.
Myths of Hearing Aids
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)
How Can I Choose a Hearing Aid?
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 the main environments where communication is a problem so the audiologist 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 to other models that generate more powerful sound and can be worn behind the ears.
Are Hearing Aids Expensive?
There is a wide range in hearing aid prices, from $1500 for a simple model to about $6000 for a very sophisticated one. Subsidies are currently available to elderly Singaporean patients aged 60 and above. 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-structured hospitals.
