Congenital degenerative cochleopathy: causes, symptoms, diagnosis, treatment

Congenital degenerative cochleopathy (congenital deafness) is caused by prenatal or intranatal pathogenic factors, manifested by deafness from the moment of the birth of the child. In most cases, the etiology of congenital deafness is not established, but among the identified causes of this disease are the following:

1. Progenetic, or hereditary, deafness accompanying many genetic abnormalities of somatic, humoral (metabolic) and functional character (Dolovits-Oldas, Edwards, Gardner-Turner, Nens, Richards-Randel, Wildervank (I), Wolf-Dolovitz-Oldes, Ziprowski syndromes and etc.);
2. metagenetic syndromes due to:
   1. embryopathies of the first three months, during which the embryo organs and systems are laid, the causes of which can be intoxications and illnesses of the mother, especially the infection with her rubella virus;
   2. embryopathies from the beginning of the 4th month of intrauterine life due to early congenital syphilis or Rh rhesus-conflict between the fetus and the pregnant mother, as a result of which degenerative-dystrophic changes in many organs and systems of the body, including snails, can occur;
3. intranatal complications associated with pathological births, a complication of which may be intracranial injury of the newborn.

According to different authors, hereditary hearing loss in various genetically determined syndromes ranges from 40 to 60% of cases; kohleopatii due to intrapartum trauma, 11-15%, Rh-conflict - 3-10%, rubella-1-5%.

Hereditary hearing loss (deafness) is usually detected very early, when parents notice that the child does not respond to the sounds and voice of the mother; sometimes several months pass before this defect is manifested. More often the disease occurs in boys. Anatomic substrate is the nervous apparatus of the cochlea, while the bone capsule of the labyrinth remains normal. The CsO can be absent completely or preserved in a rudimentary form, the cover plate does not cover the receptor cells, the cochlear passage and the sac are flattened and reduced or, on the contrary, sharply enlarged. There may also be degenerative changes in the spiral node, nerve trunk, and even auditory centers. Typically, these pathoanatomical changes are bilateral. The vestibular apparatus remains intact, the function of the equilibrium organ is not changed.

Deafness (deafness) is perceptive and irreversible. Usually they are followed by dumbness. As a rule, hereditary forms of deafness are accompanied by other genetic abnormalities, such as debility, amavrotic idiocy, retinitis pigmentosa, albinism, etc. Idiotically, in some patients, the ear maze may be completely absent.

Intratatal trauma can be caused by mismatch between the fetal volume and the dimensions of the birth canal, the application of obstetric forceps, the appearance of intracranial hematoma, the application of cranial bones to one another, and compression of the brain, etc., including the "external" trauma of the abdomen of a pregnant woman.

Birth trauma of the fetus manifests itself in three forms:

1. the fetus is born in a state of clinical death (apnea, anoxia with impaired functions of nerve centers);
2. detect fractures and cracks in the skull bones with damage to the membranes, brain substance and temporal bone (ear maze);
3. the presence of intracranial hematoma may manifest as signs of increased intracranial pressure, collapse, cyanosis, seizures, a violation of thermoregulation. As a rule, intracranial hematomas result in death, otherwise many different encephalopathies develop later. The resulting deafness, as a rule, is of a profound nature, does not progress and causes the emergence of dumbness.

Rhesus-conflict in 1/3 of cases leads to bilateral perceptual hearing loss of different severity in the absence of recruitment. Threshold tone audiograms have a downward type. Vestibular reactions can be normal, reduced or completely absent from one or both sides.

The deafness caused by the rubella virus is an integral part of Gregg's syndrome (congenital cataract, retinal abnormalities, optic nerve atrophy, microphthalmus, nystagmus, deafness, various anomalies of the external and middle ear, etc.) and is caused by a stop in the development of the cochlear structures, while the vestibular the device remains normal. Deafness is bilateral, irreversible. With partial preservation of hearing, an early hearing aid is shown for the prevention of mutism.

Prevention consists in isolating pregnant patients from other parturient women, carrying out specific and nonspecific immunotherapy.

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