Hearing loss

Hearing loss indicates that the perception of sound frequencies is weakened.

Hearing is an amazing and rather complex ability of a living organism. Thanks to the interaction of the auditory system, which consists of the outer, middle and inner ear, we can perceive the sound of the surrounding environment and communicate with people. In addition, the inner ear is responsible for the vestibular apparatus: if this function is impaired, we feel uncertainty in movements, dizziness, we lose the ability to fully walk and even stand. The human auditory system is able to distinguish sound vibrations up to 20,000 Hz.

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Causes Hearing loss

Age-related hearing loss is a fairly common phenomenon, which can be observed in 35% of people seeking help at the age of 70, and in almost 50% after 75. However, age-related changes are not the only possible cause of hearing loss; there are quite a few known factors.

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Symptoms Hearing loss

Symptoms of hearing loss can increase gradually or develop suddenly and abruptly. There is a list of common symptoms that, if detected, require a visit to the doctor for testing:

• people around you often repeat what you say twice, or even three times;
• you find it difficult to control a conversation involving several interlocutors;
• it feels like people around you are deliberately trying to speak quietly so that you can't hear;
• it becomes difficult to distinguish a conversation against the background of surrounding noise, or in a large crowd of people (in a cafe, at a meeting, on the subway);
• it is especially difficult to distinguish the speech produced by a child or a woman;
• when watching TV programs, you have to turn up the volume, which often causes irritation among family members or neighbors;
• without hearing a phrase, you often ask again or answer at random;
• in silence, a feeling of ringing in the ears may occur;
• During a conversation, you watch the speaker's lips so as not to make a mistake in what he says.

Decreased hearing ability is often accompanied by nervousness and irritability:

• you become tired from excessive listening strain when trying to understand others' conversations;
• you express dissatisfaction with your interlocutor because he speaks to you too quietly;
• avoid communicating with strangers because you are afraid that you will not understand their speech;
• Previously rich communication gradually develops into a kind of seclusion, when you consciously avoid conversations.

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Forms

Hearing loss in one ear

Hearing loss in one ear can occur for several reasons:

1. The accumulation of sulfur in the left or right ear canal is the result of the secretory function of the sulfur glands against the background of insufficient observance of the rules of hygienic care of the ears. Hearing loss may be accompanied by a feeling of a foreign object in the ear, an increased perception of one's own voice by one ear, or tinnitus. Symptoms may increase gradually, but sometimes suddenly, for example, after water gets into the ear.
2. Blood flow disorder in the arterial vessel of the labyrinth is usually a consequence of a spasm, thrombus formation or hemorrhage in the brain. Hearing loss due to vascular pathology is usually characterized by sudden and one-sided appearance. It may be accompanied by involuntary movement of the eyeball on the affected side (nystagmus) and dizziness.
3. Traumatic impact on the organ of hearing – may occur due to a mechanical cause (a blow to the ear or head), acoustic (a sudden loud sound near one ear) or as a result of electrical injury. The disease may be accompanied by pain in the affected ear, dizziness and difficulty maintaining balance. Sometimes, disorders of the autonomic nervous system are observed.

Less often, damage to one ear is observed as a complication of infectious pathologies (bacterial and viral diseases).

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Perceptual hearing loss

The cause of perceptual hearing loss may be a disorder in the inner ear or along the nerve pathways. In both cases, normal transmission of the sound impulse through the eardrum to the inner ear is observed. Depending on the location of the pathology, two types of perceptual hearing loss are distinguished:

• neurosensory impairment (or cochlear) – develops when the function of the ciliary structures in the inner ear is weakened. The cochlea loses its ability to convert information about the sound signal that comes from the middle ear into excitation waves that are transmitted to the brain via the auditory nerve. Sometimes neurosensory hearing loss can only be observed at a certain range of high sound frequencies: this type of hearing loss indicates damage to only those ciliary structures that are located at the base of the cochlea;
• retrocochlear hearing loss – develops as a result of pathology of the auditory nerve, that is, when the function of the inner ear is not impaired (information about the sound is processed), but there is no possibility of transmitting the excitation wave along the auditory nerve to the brain.

Factors in the development of perceptual hearing loss may be physiological age-related processes in the inner ear, mechanical and acoustic traumatic effects, or some inflammatory pathologies (meningitis, etc.).

Perceptual hearing loss tends to be progressive and irreversible, which may eventually require the use of a hearing aid or surgery to install a cochlear implant.

Hearing loss after otitis

Hearing loss may progress over a long period of time in chronic otitis, or occur suddenly and abruptly, sometimes within a few hours, in acute purulent otitis. After otitis, hearing may deteriorate in one or both ears. Why does this happen? The reasons may be different:

• through breach of the integrity of the eardrum (perforation);
• a large amount of sulfur or purulent discharge in the ear canal, as well as scales of epithelial tissue;
• spread of the inflammatory process to the auditory nerve.

Advanced purulent otitis can provoke the formation of dense connective tissue structures, as well as adhesions, growths, which may subsequently require surgical intervention.

Hearing loss after otitis can also be caused by taking certain medications that have an ototoxic effect: these are usually aminoglycoside antibiotics (gentamicin, neomycin, etc.), streptomycins, salicylates, quinine, and some diuretics. If you experience tinnitus and hearing loss during treatment with one of the listed medications, you should immediately stop using the ototoxic drug and consult a doctor.

Hearing loss in a child

There can be many reasons for hearing loss in a child. Almost 50% of congenital hearing pathologies are associated with hereditary diseases.

Hearing loss in old age

Age-related hearing loss initially affects the perception of high-frequency sounds: the patient reacts to household noise without changes, but begins to hear worse, for example, bird trills. Similarly, a man's voice is heard better and more clearly than a woman's.

Hearing does not decrease immediately, and it can go unnoticed for a long time. Noticeable impairments usually appear after the age of 60. Most often, this is expressed in the difficulty of communicating amidst general noise: in a supermarket, at a market.

What can be the cause of such age-related changes? This is a natural process of aging of the auditory organs, which are responsible for receiving sound signals. Ciliary structures lose sensitivity over time and stop performing their function. In addition, some changes are also observed in the areas of the brain responsible for the perception of sound information.

Associated diseases also contribute to the development of hearing loss in old age:

• atherosclerotic changes in blood vessels;
• heart failure;
• vascular pathologies due to hypertension or diabetes mellitus;
• viral and bacterial diseases (ARI, flu).

Often, hearing loss in old age is formed in youth: work in a noisy room, at work, near noisy units and machines. Deterioration increases over several decades until a combination of professional and age-related disorders occurs.

Degrees of hearing loss

Hearing loss may vary in severity. This degree is determined by a special audiometric study, the essence of which is as follows:

• using headphones, the patient is given signals of different frequencies;
• if the patient hears a sound of up to 25 decibels, then his auditory perception is assessed as normal;
• if the sound has to be amplified to 40 decibels for the patient to hear it, then there is a mild hearing loss;
• profound hearing loss is an increase in the sound signal up to 90 decibels or more.

With a severe degree of hearing loss, a person will not only not hear a conversation, but will not even react to the noise of a running motorcycle engine.

The following degrees of hearing loss are distinguished:

• norm – from 0 to 25 decibels;
• I Art. – from 25 to 40 decibels;
• II Art. – from 40 to 55 decibels;
• III Art. – from 55 to 70 decibels;
• IV Art. – from 70 to 90 decibels;
• total deafness – more than 90 decibels.

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Sudden hearing loss

A sharp deterioration in hearing occurs as a result of damage to sound-conducting or sound-perceiving receptors.

The causes of damage to the sound-conducting system are considered to be the accumulation of sulfur secretions, obstruction of the ear canal, traumatic and inflammatory processes of the middle ear.

A sharp decrease in sound perception function can be caused by damage to the cochlear vessels or a viral disease.

The most common factors for the development of sudden hearing loss are:

• cerumen plug - is a gradual accumulation of cerumen secretions in the area of the membranous-cartilaginous section of the external auditory canal. In this case, hearing may be normal until the minimum gap between the plug body and the auditory canal closes. Most often, such closure is accelerated by water entering the ear canal;
• disorder of arterial blood flow in the labyrinth - usually associated with acute cerebrovascular disease (a consequence of spasm, hemorrhage or thrombosis);
• Infectious pathology of the vestibulocochlear nerve is a disease caused by a viral or bacterial infection. Most often, this condition can develop with influenza, acute respiratory viral infections, measles, chickenpox, meningitis, etc.;
• traumatic injury to the vestibulocochlear organ – develops as a result of mechanical, acoustic, barometric or electrical impact. Traumatic injury may also include damage to the eardrum, which is most often the result of careless manipulations when cleaning the ear canal. The cause may also be the action of caustic liquids and temperature changes;
• damage to the auditory nerve caused by ototoxic drugs - most often associated with the use of streptomycin.

Decreased hearing acuity

The degree of acuity may depend on innate abilities, on compliance with hygienic rules for ear care and on many other reasons. Children's auditory organs do not differ in structure from adults, but the acuity of hearing in a child is somewhat worse. It improves over time, up to 15-18 years of age. But the limit of audibility of sound vibrations in children is higher than in an adult.

But the acuity of musical hearing depends to a greater extent on innate abilities and capabilities. If a child is not deprived of musical hearing, then from infancy he can easily distinguish the pitch of sounds, and sometimes even determine tones. Such hearing is called absolute. However, this ability of the child must be supported and developed.

Deterioration often depends on the observance of hygienic rules for the care of the hearing organs. For example, when the external auditory canal is filled with sulfur secretions (plugs), then hearing acuity can be significantly reduced: the sound directed to the eardrum is delayed by accumulations of sulfur and weakens, or does not reach the target at all. To prevent this, it is necessary to regularly clean the ear canal from internal secretions.

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Diagnostics Hearing loss

In order to assess the possibility of treatment to restore hearing, it is first necessary to conduct diagnostics that will allow us to understand in which specific part of the hearing apparatus the pathology has arisen, and for what reason.

Most often, the diagnosis of a patient suffering from hearing loss consists of the following series of procedures: tuning fork test, impedancemetry and threshold audiogram. Based on the results of the studies, appropriate treatment will be prescribed.

1. Tuning fork test. The doctor applies a tuning fork to the central part of the patient's head, after which he specifies from which side the sound vibration or oscillation is heard better. This test provides the doctor with information about the affected side and the affected conductivity - through the air or through the bone.
2. Threshold audiometry. This method indicates an increase in the patient's hearing threshold and allows one to assess the depth of hearing loss relative to the frequency range.
3. Impedancemetry. A diagnostic study that allows assessing the condition of the middle ear, responsible for the passage of airborne sound excitations. The method allows detecting the contractile activity of the auditory muscles and determining the threshold of the acoustic reflex, including the discomfort limit, as well as distinguishing pathologies of the inner and middle ear, monitoring the condition of the auditory nerve.

Before carrying out diagnostic procedures, it is advisable to be in relative silence for 16 hours before the start of the examination. If the procedure is carried out using headphones, it is advisable to remove glasses, massive earrings and other accessories that may interfere with the adequate positioning of the device.

In addition to the above procedures, vestibular tests may be prescribed to help detect problems with the inner ear that affect balance and coordination.

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Treatment Hearing loss

Treatment of hearing loss is usually done with medication, depending on the causes that caused the disorder.

Prevention

Prevention of hearing loss involves some rules that will protect your hearing organs from damage.

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Forecast

In the case of a sharp decrease in hearing, if treatment is started in a timely manner, the prognosis is favorable: about 80% of such cases end in recovery, hearing is completely or almost completely restored.

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