In the Russian Federation, according to statistics, there are approximately 12 million people with various hearing impairments. Hard of hearing and people with complete hearing loss experience a number of difficulties in normal daily life. This limits their opportunities and participation in public life. A particularly negative impact on the personality is manifested in those people who were born with normal hearing, and later, due to some circumstances, became completely deaf, or their hearing dropped sharply.
Hearing aids have been developed for the hearing impaired. Most patients use them, but sometimes their use gives too little effect. For sensorineural hearing loss, cochlear implants may help. To understand how it works, let's first understand how the ear works and why we hear, as well as briefly discuss the types of hearing loss.
Why are we hearing?
Sound is conducted through the outer and middle ear. The sound wave causes the eardrum to vibrate. Then she transmits this vibration to a chain consisting of auditory ossicles - this is a hammer, anvil and stirrup.
From the stirrup, which is located at the end of the chain of bones of the middle ear, vibrations pass into the cavity of the inner ear. It is shaped like a snail and filled with liquid. This cavity contains sensitive hair cells that convert mechanical vibrations into nerve impulses. These impulses enter the brain through the auditory nerve, where the formation and perception of the sound image that we hear occurs.
Why does hearing loss happen?
Hearing problems occur if there are disturbances at some stage of sound formation. So, if the sensitive hair cells of the inner ear are irreversibly damaged as a result of some kind of injury or illness, then complete deafness develops. It can be postlingual, if the child has already learned to speak by the time deafness develops, or prelingual, if he has not yet mastered speech.
Types of hearing loss
Features of hearing loss have their own classification, which is determined depending on the degree, location and moment of onset of deafness.
According to the degree of hearing loss, they are divided into complete deafness and hearing loss, if the perception of sound occurs, but it is difficult. Hearing loss happens:
- neurosensory;
- conductive;
- mixed.
Sensorineural is due to a hearing problem resulting from a disturbance in the inner ear or the conduction of the auditory nerves. These impairments range from mild to complete deafness.
ConductiveHearing loss occurs due to problems that have arisen in the outer or middle ear, due to which the conductivity of sound vibrations is impaired and they are distorted or not transmitted at all to the inner ear. This could be eardrum damage, wax plug, etc.
According to the age of onset, these problems can be:
- congenital;
- prelingual;
- postlingual.
According to localization, deafness can spread to one ear or both, then such a hearing loss is called binaural.
Indications for cochlear implantation
Cochlear implantation is indicated in the following cases:
- For deep sensorineural bilateral deafness.
- At a low threshold of perception in the case of using sound devices for binaural hearing aids.
- In the absence of speech perception in the case of optimally fitted hearing aids for three months, with bilateral deep sensorineural hearing loss.
- In the absence of cognitive problems (disorders of mental activity of various nature).
- In the absence of mental problems.
- In the absence of various kinds of somatic diseases.
Contraindications and restrictions
This type of implantation is ineffective in case of hearing loss that has occurred as a result of neuritis of the auditory nerve or hemorrhage in the temporal or stem lobes of the brain. Cochlear implantation in these cases will not bring the desired results.
It makes no sense to carry out the operation in casescochlear calcification (calcium deposits) or cochlear ossification (bone growth).
Cochlear implantation does not make sense if patients with hearing loss have lived in absolute silence for a long time (years). In this case, the operation will not bring the desired effect due to the fact that with a long absence of stimulation, the branches of the auditory nerve atrophy and cannot be restored.
In addition, contraindications are:
- Inflammatory processes of the middle ear.
- Presence of a perforated tympanic membrane.
- Safety and working condition of hair cells, which is determined by the method of otoacoustic emission.
- For prelingual deafness - the age of the child is more than 6 years.
- In postlingual deafness, a period of deafness that lasts longer than the period of normal hearing.
What is a cochlear implant?
The system consists of two parts, which are not interconnected by any physical methods. One part is attached behind 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 like a magnet. The second part is internal, and is a receiver. It is fixed in the temporal bone. Actually, this operation consists in installing the receiver - cochlear implantation.
How does the system work?
A microphone attached to the outer ear picks up sounds and transmits them to the speech processor located there. The received sounds are encoded in the processorand converted into electrical impulses. Then they go through a transmitter attached to the skin to a receiver located in the temporal bone. From there, they enter the cochlea through the electrode and act on the spiral ganglion of the auditory nerve. In this way, the patient is able to perceive sounds.
Cost
The total cost of a cochlear implant, examination, surgery and postoperative correction is determined individually for each patient. The number of examinations required depends on the history and general condition of the patient. So, for example, for patients with a history of meningitis, magnetic resonance imaging is mandatory, which will determine the condition of the temporal bones. For other patients, such an examination may not be carried out. Also, sometimes (not everyone) needs to consult a geneticist or a neurologist. This all affects how much a cochlear implant 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 according to the quota.
The cost of hospitalization and stay in the hospital is paid separately and depends on the rates of the chosen institution.
Necessary examinations and surgery
- Examination of an ENT doctor.
- Consultation of an otoneurologist.
- Consultation of a teacher of the deaf.
- Audiometry.
- Impedancemetry.
- Promontory test.
- Otoacoustic emission.
- Auditory evoked potentials.
- Computed tomography of the temporal bones.
- Standard laboratory tests, as for any surgical intervention (general blood and urine tests, blood glucose, biochemical blood tests).
The operation itself takes approximately 1.5 hours. The implant is fixed in the temporal bone behind the ear, and the electrodes are inserted into the cochlea. Then, within 7-10 days, dressings are performed and stitches are removed.
You can turn on the system after 3-5 weeks. The first adjustment can be carried out no earlier than one month after the operation. Here it is very important to carry it out carefully and not cause negative emotions in the patient when he returns to the world of sounds.
Simultaneous cochlear implantation is possible on both ears at once. In this case, a separate independent cochlear system is placed on each side. Examinations and rehabilitation period are the same as for unilateral implantation.
Rehab
After cochlear implant surgery, rehabilitation is an essential step. Once the speech processor is connected, it must be properly set up and the patient must be trained to perceive sounds and recognize these sensations so that he can use the information received to develop speech. Rehabilitation takes the most important, difficult and longest stage.
A whole team of specialists, including otosurgeons, deaf teachers, audiologists, psychologists, helps the patient to go through the rehabilitation period. Classes are held on special techniques and long tuning sessions, as well as consultations of all these specialists. In the future, theirobservation is necessary throughout the life of the patient. In addition, the speech processor will need to be reprogrammed periodically.
Hearing aids. Prices
For people with a low level of sound perception, 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 intra-ear - they are located in the patient's ear canal and are made to order. Digital models are also currently on sale.
In addition, there are deep canal hearing aids. They are located in the auditory canal, very small in size and almost invisible to others. But such devices are contraindicated for children under 12.
The cost of hearing aids varies but is relatively low. This enables a large number of patients to use hearing aids. Their prices are quite affordable. So, behind-the-ear models can be bought from 4.5 to 17 thousand rubles. In-the-ear devices are slightly more expensive.
Treatment for hearing loss
If hearing loss is present, treatment will depend on the underlying cause. Possible options include:
- Removal of sulfur plug - this is done by washing, sometimes using a special tool.
- Using hearing aids. In addition to behind-the-ear, intra-ear and deep-canal hearing aids, hearing aids built into the frame of glasses or pocket, as well as in the form of a headband andeven in the form of earrings. Which one is suitable for a particular patient, the otolaryngologist will consult.
- Cochlear implants - discussed in this article.
Prevention of hearing loss
Hearing loss can be caused by illness, working in a noisy environment, or prolonged exposure to a noisy environment. Hearing may also decrease due to age-related changes.
If the work is noisy, it is recommended to use earmuffs or other devices to protect against loud sounds, such as special ear plugs, at the workplace.
Regularly check the hearing of all people associated with a long stay in a noisy place. This will help to identify hearing loss at an early stage and take timely action, thereby preventing further hearing loss and the development of hearing loss or deafness.
You should avoid too loud noises during the holidays and do not listen to very loud music or at least periodically take breaks.
