Hearing aids are still the first-choice therapy for age-related hearing loss. Modern devices are small, have sophisticated microelectronic technology and can be worn either behind the ear or even in the ear canal. Today, they can compensate for almost any type of hearing loss to the extent that sufficient speech understanding and thus communication with fellow human beings are ensured.
The types of devices
The following hearing aid types are currently available:
- Behind-the-ear hearing aids (BTE hearing aids) – is worn behind the ear and is precisely fitted to the pinna using a small contra-angle (earpiece). The receiver (loudspeaker) and microphone are both located in the housing. The microphone is located below the hearing angle. The recorded sound is amplified and conducted through a transparent sound tube into the earmold (mold fitting of the hearing aid) and further into the ear canal
- RIC (Receiver in the Canal) – RIC hearing aids (synonym: ex-hearing aid): the device is worn behind the ear. Unlike the BTE hearing aid, the RIC has the receiver removed from the housing and placed directly in front of the eardrum in the ear canal via a thin cable. The shorter sound path has the advantage that there is virtually no transmission loss. The hearing system is very small, lightweight and unobtrusive. It can be used for various degrees of hearing loss.
- In-the-ear hearing aids (IdO hearing aids; IO devices) – Here, the entire technology is located in a shell, which is precisely adapted to the ear canal. ITE hearing aids are differentiated by where they sit in the ear:
- CIC (Completely In The Channel) – CIC hearing aids are located in the ear canal; they are almost invisible, except for a small nylon thread that protrudes from the pinna with a tiny ball, ensuring that the hearing aid is easy to insert and remove.
- ITC (In The Channel) – ITC hearing aids sit in the ear canal and are usually flush with the ear canal. The small visible part of the hearing system is color-matched to the natural skin tone and is therefore very inconspicuous.
- ITE (In The Ear) – ITE hearing aids (synonym: concha devices): sit in the ear canal and partially or completely fill the pinna (concha). The color is matched to the natural skin tone, so they are not very noticeable in the ear.
Furthermore, there are hearing glasses:
- Bone conduction hearing glasses
- Air conduction hearing glasses
In bone conduction hearing glasses, sound is transmitted from the temple of the glasses to the bone behind the ear, reaching the inner ear. This type of hearing glasses is used in cases of profound hearing loss or chronic ear infections, but also in cases of eczema of the auditory canal. Air conduction hearing glasses are used for moderate hearing loss. A novel treatment method for moderate to severe sensorineural hearing loss is hearing systems that can be implanted in the middle ear. Advantages of these systems include invisibility, improved sound quality, better speech intelligibility and better tolerance to loud sounds. Active middle ear implants advantages for sensorineural or mixed hearing loss. A cochlear implant is indicated (indicated) for complete deafness or even when inner ear function is inadequate. This hearing system can directly stimulate the auditory nerve electrically. Furthermore, so-called hearing therapies with trained physicians can also contribute to an improvement in acoustic abilities and thus to an increase in the quality of life in old age. Important notes! Hearing aid provision is fundamentally different from provision with glasses. While vision can be restored to 100% in very many cases with glasses, this is almost never possible with sensorineural hearing loss. The reason: the hearing threshold decreases, but the discomfort threshold remains the same or even increases. This means that hearing impaired people already perceive volumes as uncomfortable that hearing healthy people do not yet perceive as annoying or distorted. Thus, it is not sufficient to simply amplify sound linearly by means of a hearing aid, but the bandwidth of normal hearing (0 dB hearing threshold, approx. 130 dB pain threshold) must be “compressed” into a much narrower range (e.g.: hearing threshold 50 dB, pain threshold 110 dB). It is precisely this “compression” that presents the human brain with the challenge of “relearning” how to hear with hearing aids.It is obvious that the younger a patient is and the less distant the time is when he or she could still hear certain sounds via the normal pathway (“auditory memory“), the easier this is to achieve. Therefore, it is completely illogical when patients say “it’s still okay, I’d rather wait”. It will certainly not get any better, because the brain‘s ability to learn continues to decline. So the motto must be, “Hearing aid fitting as soon as the criteria for such fitting are met.”
