What are hearing aids?
Hearing aids are medical aids to improve hearing ability. They amplify the volume of voices and sounds and filter out background noise that can make it difficult to hear.
How does a hearing aid work?
In principle, the structure of a hearing aid is always the same, regardless of the model: fixed components are a microphone, an amplifier, a loudspeaker and a battery. The device uses the microphone to receive the sound signals, converts them into electrical impulses, amplifies them and transmits them into the ear canal via the loudspeaker.
Modern hearing aids are now fully digital. This means that the sound waves are converted into digital signals. A hearing aid acoustician adjusts the device on the PC – adapted to the patient’s needs. This programming offers several advantages:
- Frequencies that the hearing impaired person misses can be boosted.
- Sound ranges that the patient still perceives well, on the other hand, remain untouched.
- Disturbing frequencies can be lowered. This not only improves the auditory impression, but also protects the hearing.
Many digital hearing aids also have several programs that the user can select depending on the situation. One program is better suited to lectures, for example, while another is better suited to making phone calls.
During a conversation in a restaurant, for example, the hearing aid’s computer can use the frequency patterns to recognize which sounds are just annoying background noise and then filter them out. Important sounds, such as the words of the person opposite or the waiter, are highlighted.
At larger events such as lectures or concerts, rooms are now often equipped with an induction loop for wearers of digital hearing aids. The digital device can be adjusted so that it only amplifies the signals sent by the induction loop and blocks out the room noise.
Side effects of hearing aids
Anyone who has just been prescribed a hearing aid may suffer from side effects in the initial phase. This is because the brain first has to get used to the new level of stimulation. Voices and noises are suddenly perceived as unusually loud, and even the hearing aid wearer’s own voice may sound different at first. Other possible side effects in the initial phase are, for example
- headaches
- dizziness
- Irritation and disorientation
- Itching and inflammation with in-the-ear hearing aids
These undesirable side effects usually disappear after a while, once the brain has become accustomed to the new auditory impressions.
How much do hearing aids cost and what does the health insurance fund pay?
Hearing loss: when am I entitled to a hearing aid?
Whether you are entitled to a hearing aid if you have hearing loss depends on the degree of impairment. This is determined by an ENT specialist with the help of a sound audiogram and a speech audiogram:
- With a sound audiogram, the specialist measures your hearing ability by playing sounds of different pitches. If they detect a hearing loss of at least 30 decibels in at least one test frequency in the better ear (if you have hearing loss on both sides) or the worse ear (if you have hearing loss on one side), you are entitled to a hearing aid.
- In a speech audiogram, spoken words and numbers are played back to you at a set volume. Here, the comprehension rate at 65 decibels in the better ear (for hearing loss on both sides) or the worse ear (for hearing loss on one side) must not be more than 80 percent in order to be entitled to a hearing aid.
If the criteria from both tests are met, the ENT doctor will prescribe a hearing aid.
How much are the subsidies?
Hearing aids are subsidized by the statutory health insurance companies in the following amounts if medically necessary (as of January 2022)
- Approx. 685 euros subsidy for hearing aids, approx. 840 euros for hearing loss close to deafness
- Approx. 33.50 euros per custom-made earpiece
- Approx. 125 euros service fee for repairs
Since 2010, statutory health insurance has covered the full cost of a digital hearing aid for people with severe hearing loss if it is medically necessary.
What types of hearing aids are there?
Hearing aid models are generally divided into air conduction and bone conduction devices. The types and models of hearing aid that are suitable in each individual case depend on the underlying hearing impairment.
Air conduction devices
Air conduction devices are what is commonly known as a hearing aid. They can be worn behind the ear or in the ear and are suitable for mild to severe sensorineural hearing loss. The vast majority of all those affected (around 90 percent) suffer from this form of hearing loss, in which the inner ear, auditory nerve or auditory pathway is damaged.
Those affected not only perceive sounds more quietly, but also incompletely and distorted. Some sound signals or pitch ranges are no longer received at all.
In most cases, sensorineural hearing loss is age-related. Sometimes there are other causes, such as long-term exposure to high levels of noise, acute sudden hearing loss or vasoconstriction due to arteriosclerosis.
Behind the ear devices
Behind-the-ear hearing aids are suitable for people with mild hearing loss, but especially for those with moderate to severe hearing loss. Around two thirds of fitted hearing systems are behind-the-ear devices.
There are manually adjustable, programmable and fully automatic devices. Digital technology not only allows the volume to be adjusted automatically. The tiny computers also recognize speech and make it stand out from the surrounding noise.
Some BTE devices can be connected to audio devices or telephones using appropriate accessories. BTE devices are available in many colors; children, for example, often prefer brightly colored versions.
So-called mini hearing aids are much smaller than conventional BTEs. Small and practical, they are suitable for mild to moderate hearing loss. The sophisticated technology comes at a price, but co-payments from statutory health insurance companies are possible.
Hearing aids behind the ear and glasses do not usually go well together. In-the-ear devices are therefore generally more suitable for spectacle wearers. However, they are only suitable for mild to moderate hearing loss. Hearing glasses are an alternative.
Hearing glasses
Hearing aids for spectacle wearers combine visual and hearing assistance. You can find out more about this in the article on hearing glasses.
In-the-ear devices
The advantage of ITE devices is that they are relatively small and inconspicuous and therefore virtually invisible as hearing aids. They are easy to remove or insert. The electronics of the hearing aid are incorporated into a custom-made hollow shell. This places the microphone close to the ear canal, which comes closest to natural sound pick-up and facilitates natural directional hearing. An ITE device can also be advantageous for spectacle wearers, as the space behind the ear remains free.
However, the small size is also the main disadvantage of this type of hearing aid. Not as much technology can be accommodated in the small space as with a behind-the-ear device (BTE). For example, the BTE device amplifies sound better than the small hearing aids in the ear. In-the-ear (ITE) devices are therefore only useful for mild to moderate hearing loss. For severe hearing loss, a BTE fitting is better.
In addition, the ear canal must be of a certain size to accommodate the device. It is therefore less suitable for children. Cleaning is also more complex than with BTE.
ITE systems:
There are various ITE systems, which differ primarily in terms of size:
- In-the-canal devices are placed in the ear canal. The housing of the hearing system only covers a small part of the outer ear. The pinna remains free and the system is almost invisible.
- Complete-In-Canal devices lie completely in the ear canal. It is the smallest of all hearing aids. The housing ends inside the ear canal and is barely visible from the outside. Such virtually invisible hearing aids are only suitable for people whose ear canal is large enough to accommodate the entire hearing aid.
Bone conduction devices
These devices can be used to treat conductive hearing loss, which occurs much less frequently than sensorineural hearing loss. It is caused by mechanical factors, such as damage to the ossicles. These are responsible for amplifying and transmitting the sound signals received. If they are damaged, those affected hear more quietly without the sound quality itself being reduced.
Conductive hearing loss is caused, for example, by congenital malformations in the outer or middle ear, chronic middle ear inflammation, but also by foreign bodies such as earwax plugs that block the ear canal.
Implantable hearing aids
These devices are suitable for hearing-impaired people who cannot tolerate a conventional hearing aid, for example because they are allergic to the material used or because their ears are not suitable for a conventional hearing aid for anatomical reasons.
The hearing aids are surgically implanted in the cochlea and stimulate the auditory nerve there. They are therefore only suitable for patients whose auditory nerve is intact.
One example of an implantable hearing aid is the cochlear implant. It can be used for children and adults with severe hearing loss or deafness whose inner ear (cochlea) no longer functions.
If the auditory nerve is completely or partially damaged, a hearing implant can also be positioned directly in the brain.
Tinnitus hearing aid
A hearing aid can help against tinnitus if there is permanent noise in the ear. It plays a sound that masks the patient’s own ear noise: the ENT specialist first determines the frequency of the patient’s tinnitus and then checks whether it can be masked. The tinnitus device is then individually adjusted to these values.
If the patient also has a hearing disorder, a so-called tinnitus instrument – a combination of tinnitus device and hearing aid – can be used.
Hearing aids for children
If children have poor hearing, this can affect their entire development. A hearing aid fitted at an early age can compensate for this deficit and contribute to normal development. You can find out more about this in the article Hearing aids for children.
Hearing systems – the selection criteria
Finding the right hearing aid is no easy task. Many factors play a role in the choice of shape, technology and service. You should find the right hearing aid acoustician even before you start choosing your hearing aid. They will not only sell you the device, but also take care of fitting, maintenance and checks. For older people in particular, it is important that the store is close by or that the audiologist makes home visits. In any case, it should be easy to reach.
Make sure that the acoustician takes enough time for the consultation and responds to your wishes. Prices also play a role. They can vary greatly from store to store.
In the ear or behind it?
In order to make the right choice of hearing aid, you should describe your hearing requirements for everyday life, work and your hobbies in detail. The audiologist will then decide which hearing system is right for you.
Or do you prefer a handy, easy-to-attach model? Would you like to wear your hearing aid openly so that others know immediately? Then a BTE device may be better for you.
Analog or digital?
Which technology you choose for a hearing aid is primarily a question of price. Fully digital hearing aids are more expensive than analog versions. However, they have a number of technical features that can be very practical. However, the sound quality is not necessarily better than that of a programmable analog device.
Before purchasing a hearing aid, find out whether your statutory health insurance or private health insurance will cover the full cost of the hearing aid or how much the co-payment is. Since 2010, for example, statutory health insurance companies have covered the full cost of a digital hearing aid if it is medically necessary.
Try them out!
Before you buy a hearing aid, you should test it extensively. After the acoustician has made the earmold, you can try out the various hearing systems under everyday conditions. This test phase is absolutely essential and lasts at least one week.
Cleaning hearing aids
Hearing aids are relatively robust and can function well for many years. However, they must be handled correctly. Please note the following:
- Protect your hearing aid from dirt. Only touch it with clean and dry hands.
- Make sure that the device does not fall.
- Protect your hearing aid from extreme heat: for example, do not leave it in the blazing sun or on or next to a radiator.
- Take your hearing aid out of your ear before showering, bathing or swimming. Do not leave it in the bathroom either, as the humidity there is too high.
- Remove your hearing aid before using hairspray or face powder, for example.
- Do not leave the device lying around: children or pets are sure to find it interesting and could damage it.
- Clean your hearing aid with a soft, dry cloth. Alcohol, solvents and cleaning agents are harmful. Special care products are available from your hearing aid acoustician.
- Always transport your hearing aid in a case.
How to clean behind-the-ear systems (BTE)
For behind-the-ear systems (BTE), you must clean the hearing aid earmold:
You also need to clean the BTE hearing aid itself. Wipe it with a damp cleaning cloth or use a cleaning spray for hearing aids and then place the hearing aid in a dry bag overnight with the battery compartment open. This contains a drying capsule that can absorb moisture – unless it is an electric drying device for hearing aids. Drying capsules for hearing aids, cleaning cloths for hearing aids and drying bags or boxes are available from your hearing care professional.
In the morning, blow into the sound tube and any additional holes to remove any remaining water that has collected there. After cleaning, attach the hearing aid to the earmold and insert the BTE.
How to clean in-the-ear systems (ITEs)
In-the-ear systems (ITEs) must not come into contact with water. However, they also need to be cleaned thoroughly. The best way to do this is to use special damp cleaning cloths, which are available from your hearing aid acoustician. Wipe the ITE thoroughly and place it in a drying box for hearing aids overnight with the battery compartment open, as described for BTEs.