Hearing Aids

What are Hearing Aids

Hearing aids are small electronic devices that amplify sound and helps to hear better in quiet and noisy situations. They can be highly customized to address different types of hearing loss. 

They contain one or more microphones, and an amplifier and a receiver along with many other electronic components which help to filter out noise and provide high intelligibility. 

We now know that hearing plays a vital part in brain health because it helps people remain active and stay engaged. By keeping the brain active, hearing has been shown to reduce the risk of dementia and Alzheimer's disease. Thus hearing aid certainly improve the quality of life of a user.

The impacts of hearing loss are broad and can be profound. They include a loss of the ability to communicate with others delayed language development in children, which can lead to social isolation, loneliness and frustration, particularly among older people with hearing loss.

How Hearing Aids Work

A hearing aid amplifies sound using 3 main components- Microphone, Amplifier and Receiver.

• Microphone: Captures sound waves and converts them into electrical signals
• Amplifier: Increases the strength of the electrical signals
• Speaker/ Receiver: Produces the amplified sound waves into the ear 

Hearing aids come with wide variety of technologies and features. During the course of evolution, they are broadly classified into two categories: Analogue hearing aids (Non-Digital hearing aids) & Digital hearing aids 

Features of Hearing Aids

• Noise Reduction: Noise reduction feature is to provide less amplification to noise than to speech. This is achieved by identifying the frequencies where noise is particularly intense, relative to speech, and applying less amplification. This features identifies and understands background noise in the environment you're in and clips the level of amplification - resulting in better listening comfort and less listening effort.
• Directional Microphones: Directional microphones focusses on sounds coming from specific direction especially, the front. The use of this microphone is preferred in noisy environments, because it precisely allows the person wearing the hearing aids to focus only on the sounds in front, eliminating almost all background sounds.
• Rechargeable Batteries: Rechargeable hearing aids work similarly to traditional hearing aids, with the exception that they don't require frequent battery replacements. Instead, they come with a rechargeable battery. They are suitable for individuals who want to feel confident all day in the reliability and long-lasting power of their hearing aids. 
• Wireless Connectivity: Wireless connectivity in hearing aids is a feature that channels auditory signals from the external environment to the inner ear. The transmission of sounds from the point of origin to the recipient is achieved through the air without cables or wires.
• Remote Controls: Is a feature which enables to control or adjust your hearing aids with a click of a button. An easy way to change volume, switch programs and fine tune hearing aids without the need to physically handle them.
• Direct Audio Input: Allows the hearing aid to be connected directly to an external auditory source like Television, music player or mobile phone. This bypasses the hearing aid's microphone, which can improve the sound quality and reduce background noise. DAI is susceptible to far less interference, and yields a better quality audio signal.
• Synchronization: For an individual with two hearing aids, the aids can be programmed to function together so that adjustments made to a hearing aid on one ear (volume control or program changes) will also be made on the other aid, allowing for simpler control.

Benefits of Using Hearing Aids

• Helps to hear sounds that were not previously heard. 
• Improved ability to communicate with family, friends, surroundings and also over phone. 
• Improved communication in noisy listening situations, such as at a restaurant or in a large group of people. 
• Reduced stress. 
• Chances of delaying dementia and delaying further progression of hearing loss. 
• Over all improved quality of life. 

Types of Hearing Aids

Style of wearing refers to the position of the microphone when the device is worn.  Based on style of wearing the hearing aids are broadly classified into three types:

• Body Level Hearing Aids
• Ear Level Hearing Aids
• Canal Level Hearing Aids

Body Level Hearing Aids 

Oldest and the most economical hearing aids available. Microphone and battery are all in one case. External receiver attached to case through cord. To be clipped to pocket. 

Ear Level Hearing Aids 

Behind the ear (BTE) Most common and widely used hearing aid style. Microphone, receiver and amplifier along with battery sits in a small casing. A behind-the-ear (BTE) hearing aid hooks over the top of your ear and rests behind the ear. A tube connects the hearing aid to a custom earpiece called an ear mould that fits in your ear canal. This type is appropriate for people of all ages and those with almost any type of hearing loss.

Receiver in the ear/ Receiver in the Canal/ Canal Receiver Technology (RITE/ RIC/ CRT)

As the name indicates the receiver is placed in the canal. Microphone, amplifier and the battery sit in a small casing behind the ear. The receiver-in-canal (RIC) and receiver-in-the-ear (RITE) styles are similar to a behind-the-ear hearing aid with the speaker or receiver that sits in the ear canal. A tiny wire, rather than tubing, connects the piece behind the ear to the speaker or receiver.

A receiver-in-canal hearing aid:

• Typically has a less visible behind-the-ear portion
• Has directional microphones
• Has manual control options
• May be available with rechargeable battery
• Is susceptible to earwax clogging the speaker

Canal Level Hearing Aids 

The entire hearing aid components are placed in the shell that is custom made to the shape and size of the user’s ear canal. Cannot be prescribed to children, people with post-surgical effects such as improper canal size.

In the ear (ITE) 

An in-the-ear (ITE) hearing aid is custom made in two styles — one that fills most of the bowl-shaped area of your outer ear (full shell) and one that fills only the lower part (half shell). Both are helpful for people with mild to severe hearing loss and are available with directional microphones (two microphones for better hearing in noise).

• Includes features that don't fit on smaller style hearing aids, such as a volume control
• May be easier to handle
• Uses a larger battery for longer battery life, with several options for rechargeable batteries
• Is susceptible to earwax clogging the speaker
• May pick up more wind noise than do smaller devices
• Is more visible in the ear than smaller devices

In the canal (ITC)

An in-the-canal (ITC) hearing aid is custom molded and fits partly in the ear canal. This style can improve mild to moderate hearing loss in adults.

An in-the-canal hearing aid:

• Is less visible in the ear than larger styles
• Includes features that won't fit on completely-in-the-canal aids, but may be difficult to adjust due to its small size
• Is susceptible to earwax clogging the speaker

Other variations- Completely in the canal (CIC), Invisible in the canal (IIC) 

Digital Hearing Aids

Converts sound waves into digital signals using computer chips. Every digital hearing aid needs to be customized as per requirements and listening needs of a client, through manually adjustable trimmers (trimmer digital) or through software (digital programmable). A digital hearing aid which cannot be manually adjusted in terms of sound processing (level of noise filtration is prefixed) is called digital non-programmable hearing aid. 

Benefits of Digital technology includes: 

• Multiple listening modes for different environments or circumstances 
• Provides varying performance levels of noise filtration
• Better speech intelligibility in noisy environment. 
• More adaptable to your specific listening needs 
• Latest technology uses artificial intelligence for noise filtration.
• Less prone to feedback, such as whistling or whining 
• Usually smaller and lighter than analogue hearing aids
• Constantly monitor your environment to automatically determine the best sound quality 
• Wireless/Blue tooth connectivity options are also available in digital hearing aids. 
• Available across all wearing styles. 

Bluetooth Hearing Aids

Bluetooth is a type of technology based on radio waves that is used all over the world. It enables two or more devices to connect wirelessly (invisibly, without cables). They generally have a range of around 30 feet This is called streaming. There are Bluetooth-enabled smartphones, TVs, computers, tablets and music systems. Bluetooth comes in hearing aids too. Having a Bluetooth hearing aid helps you connect with your friends, family, colleagues, and the world in greater ways.

Choosing the Right Hearing Aid

• Anatomy of the ear- Structure of ear canal, shape and size is important to decide form factor as surgically modified structure is not suitable for custom made styles. 
• Degree, type and configuration of hearing loss - the form factor and power have to be decided primarily based on the type of loss, audiometric configuration and degree of hearing loss. Higher the degree of loss higher the power of hearing aid. 
• Life style needs - The performance level of a hearing aid has to be decided based on client’s life style requirements. This includes, their listening needs, activity levels, exposure to noise and speech in work and home environment, recreational interests.
• Client’s preferences- A balance between what the client wants in terms of cosmetic appeal, budget and listening requirements is an important factor for choosing hearing aids. 

The importance of consultation with Audiologist:

Audiologists are qualified hearing care professionals who select, fit and dispense amplification systems such as hearing aids and related devices. Therefore it is always advised to consult with a hearing care professional than purchase an over the counter hearing device that may end up not being the right one for you. 

Hearing Aid Brands

Philips: One of the most trusted and time tested brands world-wide. Known for their credibility and quality. Philips incorporates state of the art sound technology in their hearing aids to provide the listener with utmost comfort and clarity across listening situations. They offer a wide range of designs and prices in their products. 

Rexton: Known as a brand for reliability and stability since 1955. Rexton hearing aids are built to be worn at all situations. They’re durable, practical, and tested to the highest standards giving the users top notch hearing quality.

Signia: Signia is a German brand  and a leading manufacturer of hearing aids and related accessories. The company was previously known as Siemens Hearing Instruments before rebranding as Signia in 2016. Its ground-breaking Augmented Xperience platform enables augmented hearing that lets the user enjoy outstanding speech clarity with an amazing immersive soundscape in any situation.

Things to Do Before Buying Hearing Aids

It may help ease your concerns to know more about:

• The hearing aid options available to you
• What to look for when buying a hearing aid
• How to get used to a hearing aid

Hearing aids can't restore normal hearing. They can improve your hearing by amplifying sounds that you've had trouble hearing. When looking for a hearing aid, explore your options to understand what type of hearing aid will work best for you. Also:

• Get a checkup. See your doctor to rule out correctable causes of hearing loss, such as earwax or an infection. And have your hearing tested by a hearing specialist (audiologist).
• Seek a referral to a reputable audiologist. If you don't know a good audiologist, ask your doctor for a referral. An audiologist will assess your hearing, help you choose the most appropriate hearing aid and adjust the device to meet your needs. If you have hearing loss in both ears, you will get best results with two hearing aids.
• Ask about a trial period. You can usually get a hearing aid with a trial period. It may take you a while to get used to the device and decide if it's right for you. Have the dispenser put in writing the cost of a trial, whether this amount is credited toward the final cost of the hearing aid and how much is refundable if you return the hearing aid during the trial period.
• Think about future needs. Ask whether the hearing aid you've chosen is capable of increased power so that it will still be useful if your hearing loss gets worse. Hearing aids do not function indefinitely, but they should last about five years.
• Check for a warranty. Make sure the hearing aid includes a warranty that covers parts and labor for a specified period. Some dispensers may include office visits or professional services in the warranty.
• Beware of misleading claims. Hearing aids can't restore normal hearing or eliminate all background noise. Beware of advertisements or dispensers who claim otherwise.
• Plan for the expense. The cost of hearing aids varies widely. Professional fees, remote controls, hearing aid accessories and other hearing aid options may cost extra. Talk to your audiologist about your needs and expectations.

Adjusting to Hearing Aids

• Hearing aids often needs time to get adjusted to. 
• Client can expect to have improved auditory awareness, identification and localisation but discrimination and comprehension might be a challenge and it takes time for clients to get there. 
• Sometimes even after using hearing aids regularly, clients might not show targeted results, reason being that due to the degree of hearing loss and duration of unattendance to loss have major impact on auditory comprehension. 
• If hearing loss is neglected for higher duration less chances of recovery is expected, and higher the degree of hearing loss lesser the quality of auditory comprehension. 
• Initial fitting (programming) would be done based on evaluation reports and client’s inputs. 
• Follow up fitting (re-programming) will be done based on client’s experience and feedback. 
• Follow up fitting in paediatrics is done based on child response over time and care takers feedback. 

Getting Used to Hearing Aids

• Start with less noisy situations 
• Gradually move on to noisy situations over a period of time 
• Take time to get adjusted with hearing aids 
• Take breaks 
• Anticipate some frustration, especially with background noise 
• Attend follow-up visits 
• Practice your daily maintenance routine 
• Provide feedback to your hearing care professional