There are 2 main families of hearing aids : BTE and ITE.
In view of the constantly renewed requests of patients asking for a hearing aid as discreet as possible, it seemed necessary to us to evoke what is currently proposed and, especially, what one can expect from it as objectively as possible in particular on the following points:
The two main families of hearing aids
1 – The intra-canal hearing aid
It is a hearing aid that is placed in the ear canal. Its purpose is to be discreet, even almost invisible. There are different types :
•The ITC (In-The-Canal)hearing aid:
This is the least discreet of the intraductal devices.
More voluminous, it overflows the canal and hugs the concha (inner part of the ear).
Suitable for mild to severe hearing loss, its larger size makes it easier to handle.
• The CIC (Completely-in-The-Canal) hearing aid :
The most discreet of the in-the-ear hearing aids, the CIC is suitable for most hearing losses.
However, it is not recommended for hearing passages that are too narrow. It can be removed and reinserted at the user’s convenience.
•The IIC (Invisible-In-the-canal) hearing aid :
Completely invisible, the IIC has a life span of one quarter.
It is placed by a hearing care professional and worn 24 hours a day by the user.
2 – The behind-the-hear (BTE) hearing aid
It is a hearing aid which is hidden behind the auricle. The earphone output, inserted into the ear canal, close to the eardrum, flows its corrected amplification successively: into an ear tube, an elbow, and then an earmold tube before reaching the ear canal. There are two types :
• The classic BTE (Behind The Ear)
The most popular form of hearing aid, it is also the most sold (7 to 8 out of 10 hearing aids).
It consists of two parts: the BTE and the earmold. The BTE is the electronic part of the device, it is placed behind the ear. The earmold is a molding adapted to the morphology of the ear canal. It allows the maintenance and the transmission of the sound in the conduit. The two parts are connected thanks to an acoustic tube.
• The mini BTE, smaller than the classic one.
Introduced in 2004, it is more discreet than the BTE. This shape is suitable for mild hearing loss.
Our 4 points of comparison
1 – Discretion
• In the Canal :
Almost invisible or even invisible depending on the diameter of the auditory canal, a contraindication is posed in the (rare) cases where, the auditory canal being so small, the device cannot be introduced there.
• BTE :
Miniaturization technology has made it possible to create mini-bands that are more discreet than previous models. They are available in different colors to match the color of the hair. Moreover, wearing long hair can make the devices almost invisible. However, short hair, baldness, and wearing glasses make the invisibility or the installation of the device null and void.
2 – Performance
It can be assumed that the more miniaturized the hearing aid, the lower the amplification. However, this approach is no longer valid : technology has advanced to the point where the patient is free to choose in almost all cases. However, when the hearing is very severely affected (severe and profound deafness), the BTE remains better adapted. However, these cases remain rare : 80% of current hearing losses are mild or moderate presbycusis.
• In-The-Ear :
The auricle plays an indisputable role in hearing: it is known that accidental amputations of the auricle cause a decrease in hearing. The function of the pinna is to capture sounds and to focus them at the entrance of the external auditory canal. This focusing is a function of the walls of the auricle and their geometry. An in-the-canal hearing aid takes advantage of this natural property: the microphone is positioned in the outermost part of the hearing aid and picks up multidirectional sound through a two- or even three-dimensional input. This input transmits sound from several directions and helps to create a stereophonic effect that only binaural hearing aids can achieve. Its performance is therefore excellent and with amplification similar to a BTE, the result is still better.
• Behind-The-Ear :
The device is located behind the auricle, which limits its performance. It does not pick up sound from an anterior source as well as the ITE. The BTE allows for greater amplification than the ITE and is intended for the most severe hearing losses.
3 – Tolerance
• Intra-canal :
Very good with the ready-to-wear ones, because the occlusive mouthpiece is made of soft silicone, allowing a painless play of the temporo mandibular joint. In the case of custom-made devices (with impression), one can sometimes feel a tension in the auditory canal, in particular during chewing. A grinding, which slightly modifies the diameter of the auditory canal, must then be practiced to avoid this discomfort.
• Behind-The-Ear :
Excellent. The earphone which penetrates in the auditory canal, is a flexible silicon mouthpiece (cone or tulip mouthpiece): it is thus not embarrassing. However, the tip remains fragile and can break at the tube-tip junction. It can also be, sometimes, badly occluded, giving a shifted sound (digital sound of the apparatus and sound naturally perceived without amplification): the mouthpiece must then be remade.
4 – Solidity
• Intra-canal :
No particular weaknesses for a compact device. For elderly patients, adjustments (when there is a dedicated dial), insertion of the device into the ear canal and changing the batteries may be more difficult than with a BTE, due to the smaller size of the ITE.
• Behind-The-Ear :
Two areas of weakness identified :
> Loss of the earmold : it is not uncommon, as an ENT, to be asked to remove the “forgotten” earmold.
This problem seems to have been solved, as the request is becoming less frequent.
> The conductive wire that runs in the tube leading to the canal : a false contact may require a return to the hearing care professional.
This is a brief summary of the advantages and disadvantages of the two most commonly prescribed and worn types of hearing aids.
If the prescription of a device is the responsibility of the ENT specialist, the decision to use it is up to the patient. Unfortunately, it seems that the applicant is more affected than he or she chooses. Indeed, surveys show that the majority of users prefer to wear in-the-ear hearing aids for the following reasons :
- Better sound reproduction, certainly in part due to the anatomical amplifier provided by the auricle,
- Greater discretion,
- Better stereophonic quality even if only one hearing aid is worn,
- Reduction of the induced noises (wind in particular) in spite of the adapter of an anti wind elbow on the higher part of the contour of ear.
In my work, which has been going on for three decades, I am confronted with the same observation: patients wish, most of the time, to wear an intra-duct hearing aid and this wish is possible and achievable in a very large majority of cases. However, the recommendations for hearing aid practitioners are very focused on BTEs (70% of hearing aid practitioners’ sales are BTEs). The answers my patients give me when I see them fitted with a BTE leave me perplexed :
Too much hearing loss incompatible with an ITE. (…) The ITE promotes earwax build-up. (…) The ITE promotes ear canal eczema.
Note : This rarely happens, but when it does, treatment or an anti-caries shell will solve the problem.
An ITE is impossible on this side.
Note : When the ear is leaking, any device must be banned as long as the ear is leaking. First of all, it must be dried out permanently. The device will come afterwards.
The decision is up to the patient in all cases. Of course, there may be a real impossibility to wear a hearing aid intraduct. How to know ? The opinion of the ENT, who prescribed the audiogram, remains essential and, if the ENT did not specify that an ITE is possible before the visit to the hearing aid acoustician, the patient can ask for his opinion before any final decision.
Why, then, do some hearing care professionals have this attitude ? I put aside the majority of them who, as much as possible, want to satisfy their patients if the choice of a conductive instrument is possible, but what about the others ? It is unfortunate to say that a BTE will allow for greater margins for several reasons that it is good for the informed consumer to know :
- The BTE hearing aid does not require a prior mold of the ear canal ;
- The side (right / left) is indifferent : only the earmold differs according to the side and adapts on any contour ;
- The fitting of both ears is more necessary than for the in-the-ear (ITE), which already provides a rough outline of the stereophonic effect.
The cost of hearing aids is high and more and more French people, especially in certain underprivileged suburbs, cannot afford to buy a hearing aid that is reimbursed at 120 euros by the Social Security and very little generally by their Mutuelle. So two !
A responsible attitude, acceptable prices and a desire to satisfy the customer should give way to any mercantile calculation, which would certainly allow to see again, in the long run, a clientele that hesitates, waits, is wary and postpones to a later date (7 years, on average) a necessary hearing aid.