What are hearing aids?

Hearing aids are small electronic devices worn inside or behind the ear, designed to make some sounds louder and clearer. Their primary purpose is to help people with hearing loss communicate and fully participate in daily activities by amplifying sound vibrations entering the ear. These devices convert sound waves into electrical signals, then amplify them and send them to the ear through a small speaker [1].

How do hearing aids work?

A hearing aid consists of three basic parts: a microphone, an amplifier, and a speaker. The microphone picks up sounds and converts them into electrical signals. The amplifier increases the strength of these signals, and then the speaker sends them to the ear. This process helps the remaining sensory cells in the inner ear (hair cells) detect larger vibrations and convert them into nerve signals that travel to the brain [1].

Hearing aids are particularly useful for people who have sensorineural hearing loss, which results from damage to the hair cells in the inner ear. This damage can occur due to aging, illness, exposure to noise, or certain medications [1]. However, it is important to note that hearing aids do not restore normal hearing; rather, they increase awareness of sounds and their sources [1].

Common types of hearing aids

Hearing aids are available in different styles that vary in size, placement, and degree of sound amplification. The main styles include [1]:

• Behind-the-Ear (BTE): This type consists of a hard plastic case worn behind the ear that connects to a plastic ear mold placed inside the outer ear. The electronic components are located in the case behind the ear. These aids are used for all ages and for hearing loss ranging from mild to very severe [1].
• In-the-Ear (ITE): These aids fit entirely within the outer ear and are used for mild to severe hearing loss. The case containing the electronic components is made of hard plastic. Some ITE aids may include extra features such as a telecoil, which makes it easier to hear phone conversations and in public places equipped with special sound systems [1].
• In-the-Canal (ITC) and Completely-in-the-Canal (CIC): These aids are designed to fit into the ear canal. An ITC aid is custom-made to fit the size and shape of the ear canal, while a CIC aid is almost invisible inside the ear canal. These types are used for mild to moderately severe hearing loss. Due to their small size, these aids can be difficult to adjust and remove, and their limited space restricts battery power and extra features [1].

Over-the-Counter (OTC) Hearing Aids

A new category of hearing aids known as Over-the-Counter (OTC) hearing aids is available. Adults (18 years and older) with mild to moderate hearing loss can obtain them directly without needing to see a hearing specialist or obtain a prescription [2]. This category aims to increase access to hearing aids at a lower cost. However, prescription hearing aids or other devices may be necessary for more complex or severe cases of hearing loss [1].

Tips for choosing and caring for a hearing aid

The choice of the most appropriate hearing aid depends on the type and severity of your hearing loss, as well as your lifestyle. It is generally recommended to use a hearing aid in both ears if hearing loss affects both, as this provides a more natural signal to the brain and helps with understanding speech and locating the source of sound [1]. You should consult a hearing specialist to determine the most suitable device [3].

To care for a hearing aid and extend its lifespan, you should [1]:

• Keep it away from heat and moisture.
• Clean it regularly according to the instructions.
• Avoid using hair care products while wearing it.
• Turn it off when not in use.
• Replace dead batteries immediately.
• Keep batteries and small hearing devices out of the reach of children and pets.

If you experience problems such as skin irritation in the ear, injury from the device, sudden worsening of hearing loss caused by the device, or parts becoming lodged in your ear, you must report these adverse events to the relevant regulatory authorities [2]. For more information on this topic, you can visit Hearing Aids: Types, How to Choose Them, and Their Impact on Quality of Life (Arabic).

Medical references

• Hearing Aids
• Hearing Aids and Personal Sound Amplification Products: What to Know
• Devices for hearing loss