The World Health Organization (WHO) has set up a special day dedicated to ear and hearing health. March 3 is celebrated annualy as the International day for preservation of ear and hearing health.
Today, hearing impairment is considered to be the most common sensory form of disability in the world. According to WHO, approximately 360 million people suffer from deafness and hearing impairment.
In 2015, in commemoration of International вay for preservation of ear and hearing health, WHO launched the «Do not endanger your hearing!» campaign to highlight the risks of unsafe listening and promote safer practices. And for today it is being continued.
The increasing level of exposure to loud sounds in cultural and entertainment and sports facilities, such as nightclubs, discos, pubs, bars, cinemas, concert halls, stadiums and even fitness centers, is becoming an increasing concern for physicians. Modern technology is becoming more common, and often devices such as audio players are used to listen to music with unsafe volume levels and for an extended period of time. Regular exposure to loud sounds poses a serious threat to the development of irreversible hearing impairment.
WHO estimates that 1.1 billion young people in the world may be at risk of hearing impairment due to unsafe listening practices. More than 43 million people aged 12–35 years, for various reasons, have hearing impairment leading to disability.
Therefore, WHO, in collaboration with partners around the world, warnes young people and their families of the risks of hearing impairment due to noise and encourages governments to pay more attention to this issue as part of a broader effort to prevent hearing impairment in general.
What is hearing loss?
Hearing loss is a common name for diseases accompanied by hearing loss, which can develop for various reasons. The extent of hearing loss can also be different, from impairments detected only with special methods to complete deafness. With hearing loss, verbal communication is inevitably disturbed. According to various studies, the frequency of hearing loss is 2–3% of the total population, and in recent years there has been an increase in the number of cases of hearing loss.
Causes of hearing loss
Hearing loss can be early if it occurs from birth or before the child begins to speak. Such hearing loss is especially disruptive to adaptation, since the child does not initially know how the speech sounds. The causes of early hearing loss in children are usually associated with various malformations of the organ of hearing, which are caused by viral infections carried by the mother during pregnancy, and the use of toxic drugs. Sometimes deafness is hereditary, in some cases it is a part of the symptom complex of congenital diseases. Another significant factor in the pathology of hearing is prematurity. Congenital hearing loss accounts for 1 in 1000 cases of hearing decrease.
All other cases of hearing disruptions are called late hearing loss. A variety of reasons can cause them:
- Infectious diseases and their consequences (cicatricial changes, adhesions). In addition to otitis and adenoiditis, which often cause conductive hearing loss, measles, meningitis, and mumps, which cause sensorineural hearing loss, are also dangerous.
- Neuritis of the auditory nerve.
- Toxic effects, which include the administration of drugs (for example, aminoglycosides).
- Violation of the normal blood supply to the organ of hearing as a result of vascular pathologies (atherosclerosis, deformities).
- Jumps in blood pressure in case of hypertension can also cause hearing loss.
- Traumatic auditory analyzer injury.
- Traumatic skull and brain injuries.
- Long noise and vibration effects.
- Often the cause of hearing decrease is the formation of a sulfur plug, which creates a mechanical barrier to the passage of sound.
According to the development mechanism, two types of the disease are distinguished:
- Sensorineural hearing loss is associated with a disruption in the process of converting sound vibrations into nerve impulses or their transmission to the brain, so it can be manifested not only by hearing decrease, but also by a change in sound perception.
- Conductive hearing loss – a violation of sound conduction due to decreased mobility of the eardrum or auditory ossicles. May be associated with fluid accumulation, cicatricial deformities as a result of mechanical damage or chronic inflammatory processes, otosclerosis.
A combination of both mechanisms is possible - in this case it is about mixed hearing loss.
Symptoms of hearing loss
The main sign of hearing loss is hearing decrease. Depending on its severity, 4 extents of hearing loss are distinguished.
- Hearing loss of the 1st extent is characterized by a slight decrease in hearing, which is often detected only by a special examination. The auditory threshold is reduced by less than 50 decibels (dB), i.e. spoken language is audible and understoodable at the distance of 6 meters, whispering – up to 3 meters.
- Hearing loss of 2nd extent – the level of sound perception is in the range of 50–60 dB. The patient distinguishes conversational speech at a distance of up to 4 meters, and whispering – up to 1 meter.
- Hearing loss of 3 extent – the hearing threshold is in the range of 60–70 dB, whisper speech is indistinguishable, and conversational is audible at a distance of no more than 2 meters.
- Hearing loss of 4 extent – the sound threshold is in the range of 70–90 dB. In this case, we are talking about deep hearing loss, and in case of over 90 dB – about deafness, since the patient can not hear even loud speech next to him. Hearing loss of the 4th extent becomes a cause for disability.
Hearing loss can be bilateral (more typical for sensorineural) or unilateral (usually conductive). Hearing loss develops acutely or gradually – it all depends on the reasons that caused it. Chronic sensorineural hearing loss more often develops as a result of chronic inflammatory processes, vascular disorders, acute form can be caused by infection, trauma.
Separately, sudden deafness is distinguished, which develops within a few hours and is usually one-sided. It can be caused by trauma or acute blood circulatory disturbance, in some cases by viral infections (measles, mumps, herpes). In half of all the cases, the hearing is restored (partially or completely) in a few days, but it is also possible a long-term, in some cases, progressive hearing decrease.
In addition to hearing loss, patients often complain of noise or ringing in the ears. These sensations, as well as hearing loss, can be associated both with impaired sound conduction and its perception. In case of sensorineural hearing loss, patients often complain of nausea, vomiting, dizziness and impaired coordination, what is associated with the involvement of the vestibular apparatus in the pathological process.
In children, especially young children, the symptoms of hearing loss are much more difficult to detect than in adults. It is especially difficult to suspect the disease in newborns. A full-fledged diagnosis can only be performed by a children's ENT.
Symptoms of hearing loss in newborns:
- the child does not tremble with sharp sounds;
- does not respond to appeal to him, to the sound of a toy;
- does not recognize the voice of mother and relatives;
- babble of the child is not enriched with new sounds.
If you found yourself having similar symptoms, consult a doctor immediately. It’s easier to prevent the disease than to deal with the consequences.
Diagnostics of hearing loss
The diagnosis of hearing loss must necessarily include its mechanism (conductive or sensorineural) and the extent of hearing loss. When identifying the cause of hearing loss, it is also indicated in the diagnosis. The dynamics of the development of hearing loss is also assessed, whether it is progressive or stable.
The primary diagnosis of hearing loss is performed by an ENT doctor (otorhinolaryngologist). It consists in performing speech audiometry (determining the audibility of spoken and whispering speech). If a decrease in hearing is detected, the ENT directs the patient to an audiologist who conducts a more detailed examination using special equipment.
An otorhinolaryngologist can perform an otoscopy to determine or exclude changes in the middle ear, i.e. to detect possible causes of conductive hearing loss (perforation, deformation of the eardrum, the presence of adhesions) and conduct an initial differential diagnosis.
Instrumental diagnostics of hearing loss
Tuning forks tests are based on the use of special equipment – tuning forks, which can produce sounds of different frequencies. Bone and air conduction are evaluated, which helps to determine the cause of hearing loss.
To determine the nature and extent of impaired sound conduction or sound perception, various methods of audiometry are used.
Hearing loss treatment
Hearing loss is progressive in nature, so the sooner its treatment is started, the more likely it is to retain hearing. The tactics for treating hearing loss depend on its cause and extent.
Conductive hearing loss: how to treat?
With conductive hearing loss, it is necessary to restore the functional abilities of the eardrum and auditory ossicles. In case of chronic otitis media, antibacterial and anti-inflammatory therapy is prescribed, as well as antihistamines to combat tissue edema. With the vascular nature of the disease, drugs that improve cerebral circulation are effective. A good result can be gotten from physiotherapy procedures that contribute to the fight against inflammation and resorption of infiltrates. Severe adhesions, otosclerosis may require surgical intervention with partial or complete prosthetics of the affected areas of the middle or inner ear. In some cases, the only way is hearing care – using of hearing aids.
Treatment of chronic sensorineural hearing loss
At the initial stages of the disease, a good effect can be achieved with medications – nootropics improve blood circulation of the brain and auditory analyzer, B group vitamins help restore the function of nerve tissue. Drugs that improve blood supply of the brain (vinpocetine, pentoxifylline, cerebrolysin, piracetam) are prescribed first intravenously, with a gradual increase in dose, then the patient is transferred to intramuscular injection or peroral administration, continuing treatment for a long time, at least 1 month.
With vestibular disorders, betahistine has a good effect, but it should be used with caution in case of diseases of the stomach and bronchial asthma. The drug is prescribed for intake, a tablet 3 times a day during several months. The effect of treatment is noted after 2 weeks.
In parallel, physiotherapy (phonoelectrophoresis, fluctuating currents) can be used, which improves blood circulation and nutrition of the auditory analyzer. There are works proving the positive effect of hyperbaric oxygenation with sensorineural hearing loss (10 sessions of 30 minutes).
Special mention should be made for the electrical stimulation of the auditory analyzer. The essence of the method is the activation of nerve elements whose function is impaired or reduced. To do this, electrodes are attached to the projection points of the receptors and stimulation is carried out by a pulsed current.
Acupuncture with effects on active points can be included in complex therapy. Usually it is carried out in courses of 10 procedures with breaks of 1–3 months, 3 courses in total.
Conservative treatment of hearing loss of 1 and 2 extents helps to stop the progression of the disease and partially restore hearing. Full recovery using conservative treatment in case of sensorineural hearing loss cannot be achieved.
Treatment of sensorineural hearing loss of 3 and 4 extents, as a rule, surgical. Cochlear implantation is used, i.e. replacing the damaged part of the analyzer with an electronic system that performs the function of the cochlea – transforms sound vibrations into nerve impulses. It is important that cochlear implantation is indicated only for damage to the inner ear – if sensorineural hearing loss is associated with pathology of the central part of the analyzer, then this operation will be ineffective.
The use of hearing aids, which are tuned taking into account the frequency range in which there is a decrease in sound perception, remains relevant.
The treatment of hearing loss in children is based on the same principles, but special attention should be paid to the development of speech and other skills, which is facilitated by classes with a speech therapist and children's psychologist.
Forecast and risk groups
Without treatment, hearing loss will progress until complete deafness occurs. The rate of hearing loss depends on the cause of the hearing loss and the individual characteristics of the body. It has been proven that the risk factors for hearing loss are:
- elderly age;
- hereditary predisposition;
- decreased immunity and frequent infectious diseases of ENT organs;
- constant noise loads of different intensities;
- previous injuries to the ear or brain.
Prevention of hearing loss
Prevention of hearing loss comes down to regular examinations with hearing tests, especially for categories which are at risk. It is recommended to strengthen the body, timely treat diseases of the upper respiratory tract, which can be complicated by otitis media, avoid exposure to noise, and if this is impossible, use protective equipment (headphones, ear plugs). Bad habits, especially smoking, which interferes with normal blood circulation, negatively affect the state of hearing.
Head of the first otolaryngological department of the 4th City Clinical Hospital named after M. Saŭčanka
Ražkova Aliaksandra Uladzimiraŭna