In the Russian Federation, according to statistics, there are approximately 12 million people with various hearing impairments. People with hearing loss and people with total hearing loss experience a number of difficulties in their daily routine. This limits their opportunities and participation in public life. Especially negative influence on the person is shown at those people who were born with a normal hearing, and later owing to any circumstances completely have deafened, or their hearing has sharply decreased.
Hearing aids have been developed for hearing impaired people. Most patients use them, but sometimes their use gives too little effect. In the case of sensorineural hearing loss, a cochlear implant can help patients. In order to understand how it works, we will first understand how the ear works and why we hear, and also briefly discuss the types of hearing impairment.
Why do we hear?
Sound is conducted through the outer and middle ear. A sound wave leads to a vibration of the eardrum. Further, it transmits this vibration to a chain consisting of auditory ossicles - a malleus, an anvil and a stapes.
From the stapes, which is at the end of the chain of the ossicles, the oscillations pass into the cavity of the inner ear. It has the shape of a snail and is filled with liquid. In this cavity there are sensitive hair cells, which mechanical vibrations are converted into nerve impulses. These impulses go to the brain through the auditory nerve, there is the formation and perception of the sound image that we hear.
Why is hearing impaired?
Hearing problems occur if at some stage in the formation of sound disturbances occurred. So, if the sensitive hair cells of the inner ear are irreversibly damaged as a result of some trauma or disease, then complete deafness develops. It can be postlingual if, by the time of deafness, the child has already learned to speak, or prelingual, if speech has not yet mastered it.
Types of hearing impairment
Features of hearing impairment have their own classification, which is determined depending on the degree, location and the moment of onset of deafness.
In terms of the degree of hearing impairment, they are divided into complete deafness and deafness, if the perception of sound occurs, but it is difficult. Deafness can happen:
The neurosensory occurs because of a hearing problem that occurs as a result of a violation in the inner ear or conduction of the auditory nerves. The degree of such disorders ranges from mild to total deafness.
Conductive hearing impairment occurs because of problems that have arisen in the outer or middle ear, due to which the conductivity of sound vibrations is disturbed and they are distorted or not carried into the inner ear at all. It can be damage to the eardrum, sulfur plug, etc.
By the age of the offensive, these problems can be:
By localization, deafness can spread to one ear or both, then such a hearing disorder is called binaural.
Indications for cochlear implantation
Cochlear implantation is indicated in the following cases:
- With deep sensorineural bilateral deafness.
- At a low threshold of perception in case of use of sound devices at binaural hearing aid.
- In the absence of speech perception in the case of optically selected hearing aids for three months, with bilateral deep sensorineural hearing loss.
- In the absence of cognitive problems (mental disorders of a different nature).
- In the absence of mental problems.
- In the absence of various kinds of somatic diseases.
Contra-indications and limitations
This type of implantation is ineffective in case of hearing loss that occurs as a result of neuritis of the auditory nerve or hemorrhage to the temporal or stem lobes of the brain. Cochlear implantation in these cases will not bring the desired results.
It makes no sense to perform the operation in cases of calcification of the cochlea (deposition of calcium salts) or its ossification (bone germination).
Cochlear implantation does not make sense if patients with hearing loss have lived in absolute silence for a long time (for years). In this case, the operation will not bring the desired effect due to the fact that with prolonged absence of stimulation, the branches of the auditory nerve become atrophied and can not be restored.
In addition, contraindications are:
- Inflammatory processes of the middle ear.
- Presence of perforation of the tympanic membrane.
- Preservation and working condition of hair cells, which is determined by the method of otoacoustic emission.
- With prelinguinal deafness, the child's age is more than 6 years.
- With postlingual deafness, there is a period of deafness that lasts more than a period of normal hearing.
What is a cochlear implant?
The system consists of two parts, which are not connected by any physical methods. One part is attached to the outer ear and consists of a microphone and a processor (in modern models they are combined), as well as a transmitter that is attached to the skin as a magnet. The second part is internal, and is a receiver. It is fixed in the temporal bone. Actually, in the installation of the receiver and this operation is concluded - cochlear implantation.
How does the system work?
The microphone attached to the outer ear captures sounds and transfers them to the speech processor located in the same place. In the processor, the received sounds are encoded and converted into electrical pulses. Further they pass through the transmitter fixed to the skin, enter the receiver located in the temporal bone. From there they enter the cochlea along the electrode and act on the spiral ganglion of the auditory nerve. Thus, the patient gets the opportunity to perceive sounds.
The total cost of a cochlear implant, examination, ongoing surgery and postoperative correction is determined specifically for each patient. The number of necessary examinations depends on the patient's anamnesis and general condition. So, for example, for patients who had a history of meningitis, magnetic resonance imaging is mandatory, which will determine the state of the temporal bones. The rest of patients this survey can not be carried out. Also sometimes (not all) require consultation of a geneticist or neurologist. This all affects how much cochlear implantation will cost. Its cost is approximately 1 million 300 rubles. But for citizens of the Russian Federation, such an operation can be performed free of charge on a quota.
The cost of hospitalization and hospitalization is paid separately and depends on the rates of the selected institution.
Necessary examinations and operation
- Inspection of an ENT doctor.
- Consultation of otoneurologist.
- Consultation of the faculty.
- Promotional test.
- Otoacoustic emission.
- Evoked auditory potentials.
- Computer tomography of temporal bones.
- Standard laboratory tests, as for any surgical intervention (general blood and urine analysis, blood glucose, biochemical blood test).
The operation itself takes approximately 1.5 hours. The implant is fixed in the temporal bone of the behind-the-ear zone, and the electrodes are inserted into the cochlea. Next, during 7-10 days, dressings are made and seams are removed.
You can turn on the system in 3-5 weeks. The first setting can be done no earlier than one month after the operation. It is very important to conduct it carefully and not cause the patient negative emotions when returning him to the world of sounds.
Immediate cochlear implantation is immediately available on both ears. At the same time, on each side a separate independent cochlear system is put. Surveys and rehabilitation period are the same as for unilateral implantation.
After the operation "cochlear implantation", rehabilitation is an indispensable stage. After the speech processor is connected, it needs to be properly configured and taught the patient to perceive sounds and recognize these sensations so that he can use the information he has received for speech development. Rehabilitation is the most important, difficult and lengthy stage.
A whole team of specialists is helping to pass the rehabilitation period to the patient, which includes otosurgeons, surdopedagogists, audiologists, psychologists. Classes are held on special methods and long training sessions, as well as consultations of all these specialists. In the future, their observation is necessary throughout the life of the patient. In addition, periodically the speech processor will need to be reprogrammed.
Hearing Aids. Price list
For people with a low level of perception of sound, many devices have been developed - hearing aids that can help to adapt in a social environment. Hearing aids are behind-the-ear, which are attached behind the auricle, and in-the-ear - they are located in the patient's ear canal and are made to order. Currently, there are digital models on sale.
In addition, there are also deep-channel hearing aids. They are located in the auditory canal, quite small in size and almost invisible to others. But such devices are contraindicated for children under 12 years old.
The cost of hearing aids is different, but it is relatively small. This allows a large number of patients to use hearing aids. The prices are quite affordable. So, BTE models can be bought from 4,5 to 17 thousand rubles. In-the-ear devices cost a little more.
Treatment with hearing loss
If there is a decrease in hearing, treatment will depend on the reasons that caused it. Among the options is possible:
- Removing the sulfur plug - this is done by rinsing, sometimes using a special tool.
- Use of hearing aids. In addition to BTE, in-the-ear and deep-channel, hearing aids mounted in a spectacle frame or pocket, as well as a headband and even earrings can be used. Which of them will suit a particular patient, the otolaryngologist will consult.
- Cochlear implants - these were discussed in this article.
Prevention of hearing loss
Hearing loss can be caused by illness, work in a noisy environment or a long stay in a noisy place. Hearing may decrease due to age-related changes.
If the work is related to noisy production, it is recommended that headphones or other devices be used in the workplace to guard against loud sounds, for example special earplugs.
Regularly, the hearing should be checked for all people associated with a prolonged stay in a noisy place. This will help to identify hearing impairment at an early stage and take timely action, thereby preventing further hearing loss and development of hearing loss or deafness.
Avoid too loud noises during the holidays and do not listen to very loud music or at least periodically take breaks.