Possibilities of modern hearing aid

Author: Dr. İsmayıl İ. Category: Ear

Published:  2022 - 09 - Nov

According to the WHO (World Health Organization), about 10% of the world's population suffers from hearing loss. The prevalence of hearing loss in people aged 65 to 74 years is 20% and increases to 35% in people over 75 years of age. Studies have shown that approximately 65% ​​of people have grade I-II hearing loss, 30% have grade III, and 5% have grade IV or deafness.

"The impossibility of seeing separates man from things.

The inability to hear separates a person from people.

Emmanuel Kant

In addition, the statistics of recent years indicate that young and middle-aged people began to suffer from hearing loss more often, which, apparently, can be explained by the deterioration of the environmental situation, the influence of a large number of ototoxic drugs that exist today, the frequency of stressful situations, as an integral attribute of modern society , the ubiquity of computers, with the increasing influence of various noise and vibration, which is associated with the intensification of industry and agriculture. Only a third of people with hearing loss have reached retirement age. Most of them are of school and working age.

Every year, about 1500000 newborns are diagnosed with congenital hearing loss.

If we take the global statistics, more than 800 million people worldwide suffer from hearing loss. Presumably, by 2020 this number will reach 1.4 billion, which is approximately 20% of the world's population today.

It is also important to note that out of ten people who need a hearing aid, only two actually use it.

On average, people with hearing impairments wait almost ten years before they begin to understand the importance of hearing aids and take any steps to solve their problem.

First, let's take a brief look at the auditory sensory system.

This system includes: the receptor (the organ of Corti of the cochlea), the auditory nerve (VIII pair of cranial nerves), the nuclei of the medulla oblongata, the cerebellum, the inferior colliculus of the quadrigemina, the medial geniculate body, auditory radiance, the auditory cortex (field 41).

A feature of the system is the pairing and hierarchy of structures.

The hearing system is characterized by several functions:

- perceives and differentiates sound stimuli (frequency nature of sound, intensity or loudness of sound, duration of sound, timbre of sound);

- determines the direction and degree of remoteness of the sound source;

- provides auditory orientation in space;

- thanks to the auditory system, adaptation to the level of sound action is provided;

- provides (due to cortical centers) the perception of speech.

Types of hearing loss.

1- Conductive hearing loss - due to obstacles in the way of amplifying sounds. It occurs:

- at the level of the outer ear (cerumen plug, malformations of the outer ear, osteoma of the external auditory canal, otitis externa, foreign body of the external auditory canal);

- at the level of the middle ear (perforation of the tympanic membrane, chronic otitis media, otosclerosis, rupture of the auditory ossicles, pathology of the auditory tube, mastoiditis);

- due to anomalies (malformations) of ear development.

Conductive hearing loss is most often corrected with surgery. In cases where the patient does not want to be operated on or if there are contraindications to surgery, an additional appointment of a very simple hearing aid is necessary - it should simply amplify the sounds.

2- Sensorineural hearing loss - associated with a violation of the conversion of mechanical vibrations into electrical impulses. This type of hearing loss is characterized by a decrease in sound perception and its distortion, more precisely, distortion, unintelligibility of speech, especially against the background of noise.

The causes of this type of hearing loss are:

- neuritis of the auditory nerve (shingles, mumps, influenza, SARS, etc.);

- increased pressure in the fluids of the inner ear (Ménière's disease);

- age-related hearing loss (presbycusis);

- pathology of the auditory nerve (neurinoma of the vestibulocochlear nerve).

Sensorineural hearing loss is not treated either conservatively (with the exception of acute sensorineural hearing loss) or surgically. For patients with this type of hearing loss, only hearing aids can help.

3- Mixed hearing loss - a combination of the above two types of impairment. The main causes of this type of hearing loss are:

- infection of the cochlea in chronic inflammation of the ear;

- certain type and stages of otosclerosis

- a combination of unrelated pathologies of the sound-conducting structures and the sound-perceiving part of the auditory analyzer.

The most common hearing loss is sensorineural (neurosensory), it accounts for about 70-80% of all cases of hearing loss. Other forms occupy about 20-30%.

For the majority (90%) of hearing-impaired people, the quality of life can only be improved by adequate hearing aids.

Hearing prosthesis is an event that allows you to improve a person’s hearing in one way or another.

Currently, there are three types of hearing aids:

1- Reconstructive surgery on the middle and outer ear (for otosclerosis, chronic otitis, congenital anomalies, and so on);
2- Cochlear implantation is a very effective hearing restoration technique that incorporates the latest advances in otosurgery and medical technology. Every year, thousands and thousands of children with congenital or acquired hearing loss get the opportunity to fully grow thanks to cochlear implantation.
3- Prosthetics due to the transmission of auditory information through sound amplifying means - hearing aids.
Today we will dwell in detail on the last method of hearing aids - on prosthetics using hearing aids and their capabilities.

The history of the development of hearing aids with the help of hearing aids dates back to the end of the 19th century, or rather, from the discoveries of two great scientists: Alexander Graham Bell and Thomas Edison. Alexander Graham Bell electronically amplified the sound in his phone using a carbon microphone and a battery, a concept that was later adopted by hearing aid manufacturers. In 1886, Thomas Edison invented the carbon transmitter, which converted sound into electrical signals, which in turn could be transmitted through wires and then converted back into sound. This technology was used in the first hearing aids.

The first hearing aids looked like huge horn-shaped tubes with a large open section at one end that collected sounds. The wide tube gradually narrowed into a thin tube, which directed the sound to the ear.

The next milestone in the development of hearing aids was the appearance of electronic tubes, which were quickly introduced into the internal structure of hearing aids. In 1920, the first hearing aid appeared, the quality and volume of the sound signal of which were much higher. Vacuum tubes helped to achieve a more reliable transmission of electrical impulses. The size of the hearing aids themselves remained huge, which was due to the size of the batteries of the time.

However, transistors appeared further in 1952, which made it possible to reduce the size of the case. Such hearing aids were attached to the darling of the glasses, which caused discomfort. It turned out that it is more convenient to attach devices behind the ear, and already in this version they reached the end of the 20th century.

The first digital hearing aids were developed in 1990, which was the development of digital technology. They differed from their predecessors in greater adaptability to the environment, high quality of sound transmission, and therefore opened a new stage in the development of medical technologies.
Digital and computer technology continues to improve, bringing small microcircuits to hearing aids and making hearing aids miniature, allowing them to fit comfortably in the ear canal and go unnoticed.
Modern hearing aids amaze us not only with their small size, but also with their fantastic capabilities.

Hearing aids, as one of the most accessible and effective methods of compensating for hearing impairments, are gaining social importance, since they allow many patients to return to normal working life.
However, despite the stunning possibilities of modern hearing rehabilitation, only a small percentage of people with socially unfit hearing in our country received adequate hearing aid.

There are several reasons for this:
- lack of a unified state system for the diagnosis, treatment and prevention of diseases of the hearing organs;
- disastrously low awareness of the population about the social consequences of hearing loss, especially in children, and the possibilities of modern hearing aids.
As practice shows, many people, faced with the problem of hearing loss for the first time, put off the moment of contacting specialists regarding the selection of a hearing aid. They endure monstrous discomfort, try to hide from others an incomplete understanding of the speech addressed to them, but still an invisible psychological barrier prevents them from starting to use a device that would save them from this problem. This is often due to the fact that there is still an idea of ​​a hearing aid as some kind of ugly “growth” on the ear, which, moreover, is not able to fully compensate for the lost hearing.
Any person suffering from a hearing impairment needs to know that such ideas are irrelevant today: thanks to the achievements of scientific and technological progress, modern hearing aids are streamlined and skin-colored, and the latest in-ear devices are not at all noticeable from the outside. But the most important distinguishing feature of cutting-edge hearing aids is their “intelligence”. These are powerful and at the same time tiny computers that can adapt to different sound sources (cell phone, interlocutor speech, music, TV sound);

Modern hearing aids can:

- compensate for the violation of the perception of the volume of sounds;
- compensate for impaired perception of the frequency of sounds;
- ensure high speech intelligibility in various environments (in silence, in a noisy environment, on the street, in a classroom, in a classroom), that is, distinguish speech from noise, highlight and amplify it, especially in difficult sound situations (in a crowded office, in a department store , against the background of music, etc.);
- ensure the natural perception of sounds (speech, own voice, music, environmental sounds);
- automatically maintain a comfortable volume level for each case, regardless of the level of hearing loss and the severity of FUNG;
- automatically adapt to various acoustic situations (noisy environments, speech surrounded by several people, music in the halls, and so on);
- hear a wide variety of sounds - even those that a person who has not heard for a long time may have already forgotten: the rustle of autumn leaves underfoot, the rustle of rain, etc .;
- ensure the absence of whistling in the apparatus, the so-called feedback acoustic communication;
- work reliably and consume a minimum of energy for a very long time;
- provides normal communication of hearing impaired people at train stations, airports and other public places due to the so-called induction loops;
- calmly use radio and mobile phones, computers and other modern technology;

! The hearing aid is not only an assistant for auditory perception, but also a "simulator" for the central speech centers of speech intelligibility.

! Hearing aids bring back the joy of life

The majority of patients who suffer from hearing loss and do not wear hearing aids report that they feel lonely and experience a significant reduction in their quality of life.
Properly fitted hearing aids have a positive effect on the quality of life. Daily use of a hearing aid can bring back the joy of life.
Types of hearing aids:
1. Behind-the-ear hearing aids - are placed behind the ear and the tube is connected by an air duct to the in-the-ear mold, which is located directly in the user's ear canal. Modern hearing aids are tiny, come in a variety of colors and designs, are virtually indistinguishable behind the ear, and are suitable for almost any hearing loss.

2. In-the-ear and in-ear hearing aids - are placed in the ear canal. They are made individually, after making a cast of the ear canal. They are unobtrusive and comfortable. However, they should not be used in children under the age of 12 and those with profound hearing loss.

3. Pocket hearing aids - are placed outside the patient's ear area (placed in a pocket, on a belt, etc.). The hearing aid is a rectangular case and is connected by a cord to a telephone and an earmould, which are placed directly in the ear canal. These types of hearing aids are used quite rarely - mainly to compensate for hearing loss in people suffering from impaired coordination of movements or arthritis.

4. Spectacle hearing aids were designed specifically for people who wear glasses. The electronic circuitry of such an apparatus is mounted directly into the arm of the glasses, and in some models the arm also functions as a minivibrator, which has a beneficial effect on the user's vision.

5. There are also bone hearing aids in the form of hairpins, headbands. However, they have not received wide distribution.

According to the method of processing the audio signal, there are:
1. Analog hearing aids - provide only amplification and simple signal processing and have a small set of functions. Analogue devices do not have as much fine-tuning as digital ones, but, on the other hand, the sound obtained using such a device remains more alive and natural, without the metallic tint that is characteristic of a sound signal in computer processing.
2. Digital hearing aids - designed and manufactured using the most advanced sound processing technologies, provide the highest quality hearing aids, and at the same time have many functions for various life situations. Sound vibrations passing through such a hearing aid are converted into a digital format and processed in such a way as to maximize the sound quality.

There are many advantages of digital devices:
- such devices can independently adjust to the acoustic environment in which the user is located, amplifying sounds of different frequencies and volumes to varying degrees;
- they provide the patient with a “soft” comfortable sound, much better (optimal) speech intelligibility;
- these devices exclude any hearing injuries
- maximizes the possibility of improving speech intelligibility;
- automatic calculation and computer fitting of six or more prosthetic parameters based on audiometric indications, objective and subjective analysis, allow you to fine-tune the device for individual hearing loss. Preset settings, including the effect of various acoustic parameters (air vent, acoustic filter, horn effect) can also be calculated automatically;
- several parameters of such devices can be changed and compared simultaneously;
- many of these devices have several listening programs designed for different sound situations (noisy environment, quiet environment, music);
- Modern digital hearing aids are so technologically advanced that they can compensate for almost any degree of hearing loss. At the same time, the sound in the devices is as close as possible to natural sound;
- they can be reprogrammed several times at any time, every change in the parameters can be immediately listened to, and if the patient's hearing changes, there is no need to purchase a new device;
- some of them have the possibility of remote control of functions;
- for binaural prosthetics, you can set up two devices at the same time;
- the absence of trim buttons increases the mechanical reliability of digital devices;
- information for each patient, the model of the hearing aid, the parameters set during setup are stored in the hearing aid database.
Indications for hearing aids:
1 - Hearing loss more than 40 dB. In children, prosthesis is also necessary with losses of less than 40 dB, since this can prevent further distorted development of speech;
2 - With 1 degree of hearing loss (that is, with hearing loss less than 40 dB), if the patient needs more acute hearing. But, in fact, my point of view on this issue is wider than generally accepted. Hearing aids should be worn already in the earliest stages of hearing loss, since this is not only a therapeutic technique, but a preventive measure in terms of disruption of associative links between speech centers in the cerebral cortex and subcortical auditory centers. That is, hearing aids inhibit further hearing loss with age, inhibit “brain aging”;
3 - The patient notes the presence of communication problems, notes that speech intelligibility has worsened in everyday noise, tension has appeared when talking with several interlocutors, at a meeting, in a car, every time he feels the need to increase the volume of the TV, etc.;
4 - But, in my opinion, the most important indication is the presence of motivation for prosthetics.
It:
- recognition of the presence of hearing loss;
- support of family and friends.
Convincing arguments for patients in favor of hearing aids:

 - Hearing aids allow participation in everyday life.
 - Due to new technologies, modern hearing aids are portable and miniaturized.
 - Question repetition and misunderstanding will be left behind.
 - A well-tuned device that meets your requirements will never let you down.
 - Quality devices are available in any price segment.