Causes of hearing loss

The causes of hearing loss can be very diverse and can occur at different ages, as a complication after illness, or be congenital (hereditary).

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Causes of hearing loss in children

At an early age, hearing may be impaired in the case of pregnancy with a particularly high risk of developing fetal defects, infections, taking certain medications, alcoholic beverages, and narcotic substances. Less common causes are meningitis suffered at an early age, and hearing pathologies transmitted by inheritance.

Factors that can cause hearing pathology:

• early birth, low birth weight (less than 1500 grams);
• intrauterine hypoxia;
• use of drugs that affect the auditory nerve;
• injuries sustained by the child at birth.

In infancy, hearing pathologies develop with:

• bacterial meningitis;
• transferred measles, mumps;
• previous chemotherapy;
• chronic inflammation of the ear, auditory nerve;
• arthrogryposis, Moebius syndrome.

A high degree of hearing impairment is observed in:

• Developmental defects of the middle ear;
• Cerebral movement disorders;
• Stopping speech development;
• Changes in behavior – the child is aggressive, makes noise, does not communicate.

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Causes of visual and hearing impairment

The causes of visual and hearing impairment, both in adults and children, can be due to congenital and acquired pathologies. The causes of hearing impairment are divided into several categories. The first category includes:

1. Hereditary pathologies of the structure of the auditory analyzer. This is almost half of all recorded cases of hearing loss at an early age.
2. External and internal causes. As a rule, such causes include harmful effects on the fetus during pregnancy - rubella, flu, mumps, taking toxic antibiotics, Rh-conflict between the fetus and mother. Also, alcohol abuse, drugs, work associated with high noise levels, dust, etc. (especially in the first trimester of pregnancy) entail hearing pathologies in the fetus.
3. The development of hearing loss in a healthy person can occur in several ways.

• As a result of an infection of the inner ear and auditory nerve. Hearing loss is especially common after meningitis, tuberculous meningitis, scarlet fever.
• As a result of taking ototoxic antibiotics (kanamycin, streptomycin, neomycin, etc.).
• Middle ear surgeries, injuries resulting in rupture of the auditory ossicles, vegetations of the nasopharyngeal tonsil.

Visual impairment can also be congenital or acquired. Visual impairment includes any discrepancy in basic visual functions – visual acuity, color discrimination, changes in the field of vision, the nature of vision, and oculomotor functions. In turn, the cause of visual acuity deterioration lies in the impairment of the refractive function, there are three such pathologies:

• Myopia (image is fixed in front of the retina)
• Farsightedness (image is fixed behind the retina)
• Astigmatism (refraction of rays occurs in several different meridians).

Violation of the oculomotor function - strabismus and nystagmus, occur with paralysis of the eye muscles or with tumors, infections, intoxication, bleeding. Most often, strabismus in children develops after infections or after a fright. Nystagmus (high-frequency oscillation of the pupil) is a congenital genetic deviation that develops during the prenatal period, during the birth and postnatal period (with birth trauma).

Amblyopia is a dysfunction of the visual field. It occurs in various forms of strabismus, congenital refractive anomalies, tumors, cataracts, hysteria, etc.

A congenital disorder of color perception can be complete or partial (some color pairs are not perceived and a person sees objects in red or bluish-green colors). If in the case of a congenital pathology red-green colors are poorly perceived, then in the case of an acquired pathology – red, green, blue.

The causes of visual and hearing impairments must be established as soon as possible, even congenital pathologies at an early stage can be corrected and stabilized if detected in time. Acquired pathologies can also be stabilized with proper treatment, completely or partially eliminating the cause.

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Causes of persistent hearing loss

The causes of persistent hearing loss are classified as congenital and acquired. Congenital pathologies such as atresia of the auditory canal (overgrowth), atrophy of the auditory nerve are rare. Overgrowth of the auditory canal occurs in combination with other defects of the auricle, such as its underdevelopment and narrowing of the Eustachian tube. In such a situation, any inflammatory process of the ear leads to narrowing of the auditory canal and complete or partial hearing loss. Only complete overgrowth of the auditory canal leads to complete and persistent hearing loss.

Acquired hearing loss develops for various reasons. Severe persistent hearing loss usually occurs when the auditory nerve is damaged, or defects in the inner ear occur. The main causes of hearing loss are:

• Persistent complications after acute inflammatory processes in the inner ear (otitis media).
• Diseases of the nasopharyngeal cavity and nose.
• Infections - persistent hearing loss and damage to the auditory nerve as a result of meningitis, flu, mumps; inflammation of the middle ear, labyrinthitis and otitis media as a complication after measles, scarlet fever (auditory receptors are damaged and die).
• Tumor diseases.

The causes of persistent hearing loss, if diagnosed in a timely manner, can be completely eliminated or partially corrected, which guarantees hearing restoration. Based on the list of causes of acquired persistent hearing loss, it is possible to conduct timely comprehensive treatment and prevention of ENT diseases.

Causes of phonemic hearing impairment

The causes of phonemic hearing impairment can be functional and mechanical. Phonemic hearing is the ability to perceive and synthesize speech, i.e. to understand the phonemes of speech. Mechanical impairment is caused by underdevelopment or other problems of the musculoskeletal system. This category includes defects and shortening of the hyoid ligament, low tongue mobility, developmental anomalies of the tongue (when it is narrowed or too small), low tone of the lingual muscles, jaw anomalies:

• confirmation of prognathism;
• confirmation of progeny;
• confirmation of direct bite;
• confirmation of open lateral bite;
• confirmation of incorrect dental structure, defects of the palate (high palatine vault, low palatine vault, flattening of the palate, thickening of the lip and drooping of the jaw, shortened upper jaw).

Functional causes are observed in:

• incorrect speech education within the family;
• imitation of a child by people with speech defects;
• multilingualism in the family;
• prolonged sucking of a pacifier, while sucking the thumb, which leads to incorrect tone and immobility of the articulation apparatus (tongue, lower jaw).

The causes of phonemic hearing disorders, with timely differentiation and properly provided assistance, do not lead to persistent irreversible disorders of speech perception. You can fight problems of perception and synthesis of speech phonemes in a child independently, following the doctor's recommendations or by seeking help from a speech therapist.

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