According to medical statistics, from 7 to 20 percent of people in the world have anomalies and malformations of the ear, which are less commonly called ear deformities when it comes to the auricle. Doctors note the predominance of men among patients with such disorders. Anomalies and malformations of the ear can be congenital, arising as a result of intrauterine pathologies, and acquired as a result of injury, slowing or accelerating the growth of this organ. Violations in anatomical structure and physiological development of the middle and inner ear lead to deterioration or complete loss of hearing. In the field of surgical treatment of anomalies and malformations of the ear, the largest number of operations are named after doctors whose method has not undergone any new improvements throughout the history of the treatment of this type of pathology. Anomalies and malformations of the ear according to their location are discussed below.
Pinna or outer ear
The anatomical structure of the auricle is so individual that it can be compared to fingerprints - no two are alike. Normal physiological structure The auricle is considered to be when its length approximately coincides with the size of the nose and its position does not exceed 30 degrees in relation to the skull. Ears are considered protruding when this angle is or exceeds 90 degrees. The anomaly manifests itself in the form of macrotia of the auricle or its parts in case of accelerated growth - for example, the earlobes or one ear, as well as its upper part, may increase. Less common is poliotia, which manifests itself in the presence of ear appendages to a completely normal auricle. Microtia is underdevelopment of the shell, up to its absence. The “sharp ear” of Darwin, who was the first to classify it as an element of atavism, is also considered an anomaly. Another manifestation of it is observed in the ear of a faun or the ear of a satyr, which is the same thing. cat ear– the most pronounced deformation of the auricle, when the upper tubercle is strongly developed and at the same time bent forward and downward. Coloboma or splitting of the auricle or earlobe also refers to anomalies and malformations of development and growth. In all cases, the functionality of the hearing organ is not impaired, and the surgical intervention is more of an aesthetic and cosmetic nature, as, in fact, with trauma and amputation of the auricle.
Back in the first half of the last century, studying the development of the embryo, doctors came to the conclusion that the middle and outer parts develop earlier than inner ear, its parts are formed - the cochlea and the labyrinth ( vestibular apparatus). It was found that congenital deafness is explained by underdevelopment or deformation of these parts - aplasia of the labyrinth. Atresia or closure of the ear canal is a congenital anomaly and is often observed together with other defects of the ear, and is also accompanied by microtia of the auricle, disorders in the eardrum, and auditory ossicles. Defects of the membranous labyrinth are called diffuse anomalies and are associated with intrauterine infections, as well as fetal meningitis. For the same reason, a congenital preauricular fistula appears - a channel of several millimeters that goes inside the ear from the tragus. In many cases, surgical operations using modern medical technologies can help improve hearing in cases of abnormalities of the middle and inner ear. Cochlear prosthetics and implantation are very effective.
Crib
Medicine and veterinary medicine
Congenital anomalies outer ear. Congenital malformations of the external ear: anotia - congenital absence of the auricle; microtia - underdevelopment of the auricle, for example, only the lobe is missing; deformation of the auricle, for example monkey ears protruding; atresia - inflammation of the external auditory canal. Congenital malformations of the middle ear: filling of the tympanic cavity with inert tissue; absence of auditory ossicles; fusion of the auditory ossicles.
Causes of persistent hearing impairment: congenital and acquired.
Acquired hearing impairment occurs from a variety of reasons. Severe hearing impairment usually occurs when the sound-receiving apparatus (inner ear, auditory nerve) is damaged, while mild and average degree Hearing impairment can occur when only the sound-conducting apparatus (middle ear) is damaged.
Among the causes of hearing loss, the first place is occupied by the consequences acute inflammation middle ear (acute otitis media). Hearing damage in these cases is caused by persistent residual changes in the middle ear, leading to disruption of the normal mobility of the eardrum and the chain of auditory ossicles. In some cases, after acute otitis media there remains a persistent perforation of the eardrum and prolonged suppuration from the ear chronic purulent otitis. This disease is usually accompanied by significant hearing loss.
No. 18. Causes of sound-conductive hearing loss.
Conductive hearing lossthis is a hearing disorder in which it is difficult for sound waves to travel along the path: outer ear eardrum auditory ossicles middle ear inner ear.
For conductive hearing loss, conduction sound wave is blocked even before it reaches the sensory epithelial (hair) cells of the organ of Corti, associated with the endings of the auditory nerve. The same patient may have a combination of conductive (bass) and sensorineural (treble) hearing loss (mixed hearing loss). Purely conductive hearing loss also occurs.
Causes of conductive hearing loss
Outer ear
- Earwax (can cause hearing loss of 30-40 dB)
- Otitis externa inflammation of the auricle and external auditory canal, usually caused by infection (Pseudomonas aeruginosa, Proteus, Escherichia coli, staphylococcus, mycoses)
- Atresia absence of the external auditory canal.
Eardrum
Perforation (damage) of the eardrum.
Tympanosclerosis (most often a distant complication after acute otitis media).
Retracted eardrum (eg, tympanosclerosis)
In circumstances of a sudden increase in environmental pressure: during a rapid descent into a mine, a steep descent of an airplane, during diving, conditions are created when the pressure in the middle ear becomes much lower than in the outer ear. This causes strain on the eardrum and can lead to sudden conductive hearing loss. Apply various methods artificially increasing air pressure in the nasopharynx, for example, Politzer ear blowing restores pressure in the middle ear and improves hearing function.
Middle ear
Cluster serous exudate in the middle ear the most usual reason conductive hearing loss, especially in children. Home
23. Otosclerosis. The nature of auditory disorders at different localizations of the otosclerotic process.
Otosclerosis is a disease characterized by pathological growth of tissue in the bony labyrinth of the ear, leading to progressive hearing loss. It usually occurs during puberty, more often in females; the process is usually two-way.
Clinical picture characterized by progressive hearing loss and tinnitus, which is sometimes the main complaint of patients. Hearing loss in the form of a violation of the sound-conducting function, which is usually caused by fixation of the base of the stapes in the window of the vestibule of the inner ear, is referred to as the tympanic form of otosclerosis. If the focus is localized in the area of the cochlear window or in the cochlea, hearing loss occurs according to the type of sound perception disorder (mixed and cochlear
21. Diseases of the external ear. Atresia. Foreign bodies of the ear. Sulfur plug.
Diseases of the external ear (otitis).
- Perichondritis of the auricle (inflammation of the perichondrium) - inflammatory process localized in the area of the auricle, without involving the earlobe, manifested by redness, swelling, and pain.
- Erysipelas manifests itself as redness, swelling, which has clear boundaries, with a possible transition to the tissue of the lower layer. Accompanied by fever, chills, and changes in the blood. When touched, there is sharp pain.
- Otohematoma (bleeding in the area of the auricle) occurs in sports, household injuries and in people who often lie on one ear for a long time. Accompanied by tissue delamination between the skin and perichondrium as a result of hemorrhage. Most often this occurs in the upper third of the auricle; a bubble filled with blood forms.
- External diffuse otitis can be caused by bacterial, fungal infections or have an allergic nature. General manifestations: itching of the skin, purulent discharge from the ear, pain when pressing on the tragus. When examined using an ear funnel (otoscopy), hyperemia (redness), infiltration (swelling) of the skin of the membranous-cartilaginous part of the external auditory canal is determined, its lumen sometimes narrows to such an extent that the eardrum becomes immense.
Atresia of the external auditory canal. With atresia of the external auditory canal, hearing loss is in the nature of damage to the sound-conducting apparatus, i.e. it is mainly the perception of low sounds that suffers; the perception of high tones is preserved, bone conduction remains normal or even slightly improves.
22. Acute and chronic catarrh of the middle ear. The mechanism of their occurrence. Acute purulent otitis media. Chronic inflammation of the middle ear. Complication of acute and chronic otitis media.
Qatar of the middle earit's not purulent inflammation auditory tube, in which its function is impaired. The main causes of the disease: inflammatory diseases nose, nasopharynx, ARVI, allergic diseases.
As a result of one or another disease of the nose, paranasal sinuses, nasopharynx (runny nose, sinusitis, adenoids), inflammation or swelling of the mucous membrane of the auditory tube occurs and its patency is impaired. Air does not enter the middle ear cavity, which leads to a decrease in pressure in it and retraction of the eardrum.
Symptoms: patients complain of a feeling of congestion in the ear, heaviness in the head, decreased hearing, increased perception of one’s own voice, and a feeling of fluid transfusion in the ear.
Spicy catarrhal otitis media if the causes causing the obstruction of the auditory tube are eliminated, recovery may result in a few days: the eardrum assumes its normal position and hearing is restored. If the patency of the auditory tube is impaired for a long time, then the process can enter a chronic stage with the development of adhesive otitis media, in which scars and adhesions form in the tympanic cavity. They limit
24. Inflammation of the inner ear, characteristic features inflammation, disease outcome, residual effects.
The inflammatory process of the inner ear (labyrinth) can be acute and chronic. The infection penetrates into the inner ear (cochlea) in various ways: through the middle ear - with purulent inflammation, through the meninges with meningitis, through the blood - with various infections.
Inflammation of the inner ear is caused by the same microorganisms that are found in the middle ear during acute and chronic purulent inflammation. Damage to the labyrinth can be purulent or non-purulent, and its distribution can be diffuse or limited.
Symptoms and course: initially there is tinnitus, dizziness, hearing loss, nausea, vomiting, balance disorder. There is nystagmus involuntary movements eyeball to the side. Dizziness can be of varying intensity, imbalance is observed at rest and during
25. Acoustic neuritis. Central lesion auditory analyzer.
Acoustic neuritis - damage predominantly to the cochlear part of the vestibulocochlear nerve ( VIII pairs of cranial nerves), leading to hearing loss. At the same time pathological process localized at the level of the first neuron of the auditory pathway.
May be caused by inflammation and atrophic changes as a result various factors. Among the many reasons are toxic substances, including medications (mycin antibiotics, quinine), various infections (influenza, brucellosis, etc.), diseases of blood vessels, heart, kidneys, metabolic disorders, prolonged irritation by noise, damage to the middle and inner ear.
26. Prevention hearing impairment in children and adults. The effect of noise on the body.
Prevention of deafness and hearing loss should begin long before the birth of the child. Future parents should not abuse alcohol and do not have the right to marry blood relatives, as a result of which deaf children are often born. TO congenital disorders hearing disorders include malformations of the ear, external auditory canal, and underdevelopment of the ear.
Diseases at the beginning of pregnancy are the most dangerous, as they can lead to underdevelopment of the fetal ear. The causes of hearing loss can be premature and prolonged labor, various injuries, and fetal suffocation.
From a preventive point of view, it is important to know that a sharp sound can cause pain and even dizziness, which can also lead to hearing loss, although it passes quickly in many cases.
Untimely removal of foreign bodies from the ear, improper nose blowing, systematic self-removal of wax, difficulty nasal breathing, various injuries common causes of hearing loss that can be eliminated.
Acquired deafness is often caused by infectious diseases (mumps, influenza, epidemic cerebrospinal meningitis, scarlet fever), traumatic brain injury, and diseases of the endocrine system.
The predisposition to hearing loss can be inherited. The earlier signs of damage to the ear canal are identified, the more timely the treatment, the greater the chance that the child will not remain hard of hearing or deaf. Mass inspections are carried out to identify early forms hearing loss.
The main methods in the prevention and treatment of deafness and hearing loss are rational nutrition, hardening of the body, proper nasal breathing (removal of foci of infection, treatment concomitant diseases, removal of adenoids, polyps, correction of the nasal septum).
If there is hearing loss, hearing aids are necessary to prevent the development of deafness. Not subject to
20. Malformations of the outer, middle and inner ear. Hearing disorders in these diseases.
Congenital anomalies of the external ear. Very often combined with congenital malformations. Occurs in 1:10,000 children.
Congenital malformations of the external ear:
Anotia congenital absence of the auricle;
Microtia underdevelopment of the auricle (for example, only the lobe is missing);
Deformation of the auricle (for example, monkey ears protrude);
Atresia fusion of the external auditory canal.
Congenital malformations of the middle ear:
Filling the tympanic cavity with inert tissue;
Absence of auditory ossicles;
Fusion of the auditory ossicles.
Congenital malformations of the inner ear:
Absence of a labyrinth or underdevelopment of its individual parts
Underdevelopment of the organ of Corti (most often hair cells).
19. Causes of sound-perceiving (sensorineural) hearing loss.
Sensorineural hearing lossthis is hearing loss caused by damage to the structures of the inner ear, the vestibulocochlear nerve (VIII), or central departments auditory analyzer (in the brainstem and auditory cortex).
Sensorineural hearing loss is caused by defects in the sensory epithelial (hair) cells of the spiral (Corti) organ, the cochlea of the inner ear.
The most common type of sensory hearing loss is caused by improper functioning of hair cells when they are either initially defective or have been damaged during a person's life.
Sensorineural hearing loss can occur as a result of an abnormality of the VIII cranial (auditory) nerve.
Sensorineural hearing loss due to damage to the central parts of the auditory analyzer is called hearing loss of central origin.
hearing aids for children with unilateral hearing loss. Currently, hearing-improving operations for various diseases ear (otosclerosis, chronic purulent inflammation), congenital ear deformities (closed ear canal, absence of auricles, etc.) are recommended not only for adults, but also for children, regardless of age.
The effect of noise on the body.
Noise creates a significant load on the human nervous system, having a psychological impact on him.
It is known that a number of such serious diseases as hypertension and peptic ulcer, neuroses, gastrointestinal, skin diseases, pathological changes, are associated with overstrain of the nervous system during work and rest. Lack of necessary silence, especially at night, leads to premature fatigue and often to illness. As levels increase to 70 dB and above, noise can have certain physiological effects on a person, leading to visible changes in his body. Under the influence of noise exceeding 85-90 dB, hearing sensitivity at high frequencies is primarily reduced.
Loud noise has a detrimental effect on people's health and performance. A person, working in noise, gets used to it, but prolonged exposure to strong noise causes general fatigue, can lead to hearing impairment, and sometimes to deafness, digestion is disrupted, and changes in volume occur. internal organs. By affecting the cerebral cortex, noise has an irritating effect, accelerates the process of fatigue, weakens attention and slows down mental reactions.
Any noise of sufficient intensity and duration can cause varying degrees decrease in auditory activity. In addition to the frequency and volume level of noise, the development of hearing loss is influenced by age, hearing sensitivity, duration, nature of the noise, etc.
When exposed to noise, it is very high levels(more than 145 dB) the eardrum may rupture.
Treatment of atresia of the external auditory canal can only consist of artificial restoration of the lumen through plastic surgery.
Sulfur plug . The reasons for this accumulation may be: 1) increased function of the sulfur glands; 2) narrowness and abnormal curvature of the external auditory canal, making it difficult to remove wax out; 3) abnormal chemical properties sulfur: its increased viscosity, stickiness, which promotes the adhesion of sulfur to the walls of the ear canal.
Treatment for earwax plugs is very simple: after preliminary softening with special drops, the plug is removed by rinsing the ear with warm water from a special syringe. Such washing can only be performed by a doctor or specially trained medical worker. Any attempt at self-removal sulfur plugs using any kind of sticks, spoons, hairpins, etc. are unacceptable.
Foreign bodies . The presence of a foreign body in the ear, even for several days, cannot cause harm, so a child with a foreign body should be taken to a specialist doctor as soon as possible, and pre-medical measures may include the following:
1) killing living foreign bodies by putting a few drops of some clean substance into the ear liquid oil(warm);
2) for swelling foreign bodies (peas, beans, etc.), pouring warm alcohol into the ear in order to cause the foreign body to shrink;
3) for non-swelling bodies (beads, pebbles, cherry pits), as well as living foreign bodies: carefully rinse the ear with warm boiled water from an ordinary rubber syringe.
mobility of the eardrum and the chain of auditory ossicles and contribute to persistent hearing loss.
Acute purulent otitis mediaacute inflammatory process of the middle ear. Caused by a viral bacterial and fungal infection. As a rule, the infectious process spreads to the middle ear from the nasal cavity and nasopharynx, and as a complication of colds, acute respiratory infections, sinusitis, sore throat and other diseases of the upper respiratory tract.
Symptoms : shooting pain in the ear, decreased hearing, elevated temperature, purulent discharge from the ear. If you don't start timely treatment, pus appears in the middle ear cavity, which ruptures the eardrum and flows out of the ear. This process occurs especially quickly in infants.
With timely and proper treatment acute otitis in most cases ends in recovery, however, with weakening of the body and other unfavorable conditions, it can turn intochronic form: in this case, persistent perforation, partial or complete defect of the eardrum, constant or periodic suppuration, and decreased hearing occur.
For otitis mediapossible intracranial complications (inflammation of the inner ear, meninges(meningitis), etc.). In case of intracranial complications, urgent surgical treatment ear.
movement. With purulent labyrinthitis, there is an increase in temperature and a violation general condition, with diffuse purulent labyrinthitis, complete loss of hearing occurs.
Complications: inflammation of the meninges, meningitis, cerebellar abscess.
For labyrinthitis, complex conservative and surgical treatment is carried out. Drug treatment is aimed at reducing pressure inside the labyrinth, preventing the transition of serous inflammation to purulent inflammation and preventing the development of intracranial complications.
Must be assigned antibacterial therapy the antibiotic is selected taking into account the sensitivity of microorganisms to it; antibiotics are administered intramuscularly or intravenously.
Absolute indication before surgery is purulent labyrinthitis with intracranial complications.
Symptoms and course.
The main complaints are noise, ringing in the ear of varying intensity and hearing loss. The hearing loss can be significant, and sometimes complete deafness can develop in one or both ears. Balance problems and dizziness may occur.
When examining the ear, no pathological changes are noted. The diagnosis is established after a hearing test and audiometry.
An audiological study reveals the nature of hearing damage and consists of determining the thresholds of hearing sounds of various frequencies for air and bone conduction. With neuritis, conduction through the bone decreases; in the presence of pathology, air conduction also decreases in the middle ear. Then they talk about mixed form hearing loss.
A common cause of hearing damage is diseases of the nose and nasopharynx and the obstruction associated with these diseases. eustachian tube.
Damage to the nuclei of the auditory nerve, its pathways in the brain, as well as the cortical auditory centers, both in frequency and in the degree of hearing impairment that occurs with them, are comparatively less important.
Important role Acute infectious diseases play a role in the occurrence of persistent hearing impairment. Most infectious diseases cause hearing damage. Of the infectious diseases that cause persistent hearing damage, highest value have epidemic cerebrospinal meningitis, measles, scarlet fever, influenza, mumps.
Some infectious diseases (meningitis, viral flu, mumps) cause damage to the nervous apparatus of the auditory analyzer (organ of Corti or auditory nerve trunk), others (measles, scarlet fever) primarily affect the middle ear, and the inflammatory process that develops not only leads to disruption functions of the sound-conducting apparatus of the middle ear, but can also cause diseases of the inner ear (serous or purulent labyrinthitis) with partial or complete death of the receptor cells of the organ of Corti.
Hearing impairment and usually simultaneously developing dysfunction of the vestibular apparatus in cerebrospinal meningitis is caused by an inflammatory process in the inner ear - purulent labyrinthitis, resulting from the spread of purulent infection from the meninges through the internal auditory canal along the auditory nerve sheaths.
cause infection of the ear (pathogens bacteria, viruses, or fungi most often penetrate into the auditory tube from the nasopharynx (rhinotubar) or, in case of injury to the eardrum, through the external auditory opening or obstruction (blocking) of the auditory (Eustachian) tube due to an allergic process or tumor growth. Obstruction of the auditory tube leads to the fact that the pressure in the middle ear becomes higher than in the outer ear, which impedes the mobility of the auditory ossicles of the middle ear and the eardrum.
Conductive hearing loss can result from deformation or separation of the auditory ossicles.
Usually
- Acute otitis media catarrhal or purulent
- Chronic otitis media exudative (secretory), adhesive (with the formation of adhesions and scars), recurrent or purulent.
- Otitis media acute or chronic inflammation middle ear requires compulsory treatment specialists, since it is fraught not only with the development of hearing loss, but also with such dangerous complications as mastoiditis, paresis or paralysis facial nerve, labyrinthitis (inflammation of the inner ear), otogenic meningitis, otogenic abscesses of the brain and cerebellum.
Rarely
- Cholesteatoma is a pathological growth of the epithelium that can impede the function of the auditory ossicles; if left untreated, it can lead to caries of the auditory ossicles and their deformation.
- Middle ear tumor
- Otosclerosis overgrowth bone tissue around the base of the stirrup
- Temporal bone injury
Inner ear
- Severe forms otosclerosis
- Exposure to intense noise
- Obstruction of the oval or round window this type of hearing loss is usually treated with surgery
forms of otosclerosis). At the beginning of the disease, hearing loss can be one-sided; later (after several months, sometimes several years), hearing decreases in the second ear. In a significant proportion of cases, a paradoxical symptom is expressed ( paracusis Willisii ): patients hear better in noisy environments - on the street, in transport. The process often develops gradually, slowly.
The progression of hearing loss can be temporarily suspended, resuming under the influence of unfavorable factors. Sometimes the disease develops quickly (transient form), which is usually observed in adolescence, as well as with the hereditary nature of otosclerosis.
Treatment of otosclerosis in most cases is surgical, because conservative methods ineffective.
As well as other works that may interest you |
|||
| 30564. | Convergence of a number series. Harmonic series. Common term and remainder of the series. Signs of series convergence | 133.5 KB | |
| Harmonic series. Common term and remainder of the series. Signs of convergence of series Definitions. | |||
| 30566. | Functional series. Basic concepts and definitions. Uniform convergence of functional series. Weierstrass sign. Properties of uniformly convergent series | 31.56 KB | |
| Functional sequence uniform convergence and properties Definition: uniformly convergent to fx on X if the inequality is satisfied. Note: if a sequence of a function uniformly converges to a function then it simply converges to it. On the uniform convergence of a function: in order for it to converge uniformly on X to fx, it is necessary and sufficient that the inequality Uniformly convergent functional series be satisfied Definition: uniformly convergent on X if the sequence of its partial sums is uniformly... | |||
| 30567. | Basic trigonometric system of functions. Fourier series for orthogonal systems of functions. Trigonometric Fourier series. Signs of convergence of trigonometric Fourier series. Trigonometric Fourier series for even and odd functions | 142.57 KB | |
| Trigonometric series 1 is called the Fourier series for a function on a segment, and the coefficients calculated using formulas 2 3 4 are called Fourier coefficients. piecewise monotonic then the Fourier series of the function defined by the formulas 1 2 3 4 converges almost everywhere except the discontinuity points to fx. For even function For an odd function Presentation Let the function be defined on ℝ. The smallest of these numbers T is called the period of the function. | |||
| 30568. | Properties of the distribution function | 51.52 KB | |
| Properties of the distribution function: Property 1: 0 ≤ Fx ≤ 1. Property 2: Fx2 ≥ Fx1 if x2 x1. Property3: 1Fx = 0 for x ≤ ; 2 Fx = 1 for x ≥ b. Property4: Fx0 = Fx0 0. | |||
| 30569. | Convergence almost certainly and in probability | 352.78 KB | |
| If then for any Generalized Chebyshev inequality If then for any Chebyshev inequality If exists then for any ZBC Chebyshev ZBC if convergence of Markov ZBC if t. If exists then for any Definition of ZBC. It is said that a sequence of random variables with finite first moments satisfies the law of large numbers, if the Law of Large Numbers is usually called statements about the conditions under which a sequence of random variables satisfies the law of large numbers. ZBCH Chebyshev. | |||
| 30570. | Characteristic function of a random variable: definition and properties. Characteristic function of normal distribution | 47.71 KB | |
| Characteristic function of a random variable: definition and properties. Characteristic function of normal distribution. HF of a normal distribution: Speech The characteristic function of a random variable is one of the ways to specify a distribution. Characteristic functions may be more convenient in cases where, for example, the density or distribution function has a very complex form. | |||
| 30571. | Continuity theorem. Central limit theorem. Moivre-Laplace integral theorem | 49.24 KB | |
| Central limit theorem. Integral theorem of Moivre-Laplace. Conversely, if at each point of continuity the function is a distribution function, then at each point t there is a characteristic function for the distribution function Moivre-Laplace integral theorem: If the probability p of an event in each trial is constant and different from both zero and one, then the probability that the event appears in n trials from to times approximately equal definite integral: Where. | |||
All defects, damage and inflammation of the inner ear are associated with damage to the sound-receiving apparatus.
Inner ear defects can be congenital or acquired. Birth defects occur when the mother’s body is exposed to adverse factors (intoxication, infection, injury to the fetus) that disrupt the normal course of embryonic development. In most cases, to birth defects inner ear refers to the underdevelopment of receptor hair cells of the entire organ of Corti or its individual sections. In place of the hair cells, a tubercle of nonspecific epithelial cells is formed, and sometimes the main membrane turns out to be completely smooth. Depending on the degree of damage to the organ of Corti, hearing loss will be complete or partial.
Acquired defects are associated with damage to the structures of the inner ear during childbirth as a result of compression and deformation of the fetal head by narrow birth canal or when pathological childbirth. In young children, damage to the inner ear can occur when the head is bruised during a fall from a height.
Inner ear inflammation(labyrinthitis) is less common than middle ear and is almost always a complication of otitis media or a severe general infectious disease.
More often labyrinthitis occurs when a purulent inflammatory process passes from the middle ear through the oval or round window into the inner ear. For chronic purulent otitis the infection can pass through the bone wall damaged by pus, separating the middle ear from the inner ear, if the outflow of purulent exudate from the tympanic cavity is obstructed. In some cases, inflammation of the labyrinth is caused not by microbes, but by their toxins. Under the influence of purulent exudate, the membranes of the oval and round windows swell, and they become permeable to bacterial toxins. In this case, inflammation proceeds without suppuration and usually does not lead to the death of the nerve elements of the inner ear. Therefore, complete deafness does not occur, but a significant decrease in hearing is often observed due to the formation of scars and adhesions in the inner ear.
Inflammation of the inner ear can be caused by other reasons. In the early childhood with epidemic cerebrospinal meningitis (purulent inflammation of the meninges), the infection can penetrate into the inner ear from the meninges along the sheaths of the auditory nerve, which passes through the internal auditory canal. Sometimes labyrinthitis develops as a result of infection through the bloodstream during common infectious diseases (measles, scarlet fever, mumps or mumps, etc.).
According to the degree of prevalence of the inflammatory process, diffuse (spread) and limited purulent labyrinthitis are distinguished. With diffuse purulent labyrinthitis, the organ of Corti completely dies, the cochlea is filled with fibrous connective tissue, complete deafness occurs.
With limited labyrinthitis, the purulent process affects only part of the organ of Corti, and partial hearing loss occurs for certain tones, depending on the location of the lesion in the cochlea.
Complete or partial deafness that occurs after purulent labyrinthitis turns out to be persistent, because the dead nerve cells The organ of Corti is not restored.
With labyrinthitis, the inflammatory process can spread to the vestibular apparatus; in addition to hearing impairment, the patient experiences nausea, vomiting, dizziness, and loss of balance.
V.E. Kuzovkov, Yu.K. Yanov, S.V. Levin
St. Petersburg Research Institute of Ear, Throat, Nose and Speech
Cochlear implantation (CI) is currently generally accepted in world practice and is the most promising direction rehabilitation of persons suffering from high-grade sensorineural hearing loss and deafness, with their subsequent integration into the hearing environment. IN modern literature the issues of classification of developmental anomalies of the inner ear, including in relation to CIs, are widely covered, described surgical techniques conducting CI for this pathology. The world experience of CI in persons with developmental anomalies of the inner ear spans more than 10 years. At the same time, there are no works on this topic in the domestic literature.
At the St. Petersburg Research Institute of Ear, Throat, Nose and Speech, for the first time in Russia, CI began to be performed on people with developmental anomalies of the inner ear. Three years of experience in such operations, the presence of successful results of such interventions, as well as an insufficient amount of literature on this issue, served as the reason for carrying out this work.
Classification of developmental anomalies of the inner ear. Current state of the issue.
With the advent of the late 80's - early 90's. computed tomography(CT) high-resolution and magnetic resonance imaging (MRI), these techniques have become widely used for diagnosing hereditary hearing loss and deafness, especially when determining indications for CI. With the help of these progressive and highly accurate techniques, new anomalies were identified that did not fit into the existing classifications of F. Siebenmann and K. Terrahe. As a result, R.K. Jackler proposed a new classification, expanded and modified by N. Marangos and L. Sennaroglu. However, it should be noted that MRI in particular currently reveals such fine detail that the malformations detected can be difficult to classify.
In his classification of developmental anomalies of the inner ear, based on conventional radiography and early CT data, R.K. Jackler took into account the separate development of the vestibular semicircular and vestibular cochlear parts of a single system. The author suggested that various types anomalies appear as a result of a delay or disruption of development at a certain stage of the latter. Thus, the types of malformations detected are correlated with the time of disruption. Later, the author recommended classifying combined anomalies as category A, and suggested a connection between such anomalies and the presence of an expanded aqueduct in the vestibule (Table 1).
Table 1
Classification of developmental anomalies of the inner ear according to R.K.Jackler
| Category A | Cochlear aplasia or malformation |
| 1. Aplasia of the labyrinth (Michel anomaly) 2. Cochlear aplasia, normal or deformed vestibule and semicircular canal system 3. Cochlear hypoplasia, normal or deformed vestibule and semicircular canal system 4. Incomplete cochlea, normal or deformed vestibule and semicircular canal system (Mondini anomaly) 5. Common cavity: the cochlea and vestibule are represented by a single space without internal architecture, normal or deformed system of semicircular canals POSSIBLE presence of an expanded aqueduct of the vestibule |
|
| Category B | Normal snail |
| 1. Dysplasia of the vestibule and lateral semicircular canal, normal anterior and posterior semicircular canals 2. Expanded aqueduct of the vestibule, normal or expanded vestibule, normal system of semicircular canals |
Thus, items 1–5 of categories A and B represent isolated developmental anomalies. Combined anomalies falling into both categories should be classified as category A in the presence of an expanded vestibular aqueduct. According to R.K. Jackler, S. Kösling made the statement that isolated anomalies represent not only a deformation of one structural unit of the inner ear, but can be combined with anomalies of the vestibule and semicircular canals, as well as with vestibular dysplasia and an enlarged aqueduct of the vestibule.
The N. marangos classification includes incomplete or aberrant development of the labyrinth (Table 2, item 5).
Table 2
Classification of developmental anomalies of the inner ear according to N. Marangos
| Category | Subgroup |
| A = incomplete embryonic development |
1. Complete aplasia of the inner ear (Michel anomaly) 2. Common cavity (otocyst) 3. Aplasia/hypoplasia of the cochlea (normal “posterior” labyrinth) 4. Aplasia/hypoplasia of the “posterior labyrinth” (normal cochlea) 5. Hypoplasia of the entire labyrinth 6. Mondini dysplasia |
| IN = aberrant embryonic development |
1. Expanded aqueduct of the vestibule 2. Narrow internal auditory canal (intraosseous diameter less than 2 mm) 3. Long transverse ridge (crista transversa) 4. Internal auditory canal, divided into 3 parts 5. Incomplete cochleomeatal separation (internal auditory canal and cochlea) |
| WITH = isolated hereditary anomalies |
X-linked hearing loss |
| D | Anomalies in hereditary syndromes |
Thus, four categories (A-D) of inner ear malformations are described. The author considers the aqueduct of the vestibule to be dilated if the interosseous distance in the middle part exceeds 2 mm, while other authors give a figure of 1.5 mm.
L. Sennaroglu differentiates 5 main groups (Table 3): anomalies of the development of the cochlea, vestibule, semicircular canals, internal auditory canal and aqueduct of the vestibule or cochlea.
Table 3
Main groups and configurations of cochleovestibular anomalies according to L. Sennaroglu
Cochlear malformations (Table 4) were divided by the author into six categories depending on the time of disruption of the normal course embryonic development. This classification of cochlear malformations includes an incomplete separation of types I and II.
Table 4
Classification of cochlear anomalies according to the time of disruption of intrauterine development according to L. Sennaroglu
| Cochlear malformations | Description |
| Michel Anomaly (3rd week) |
Complete absence of cochleovestibular structures, often - aplastic internal auditory canal, most often - normal aqueduct of the vestibule |
| Cochlear aplasia (end of 3rd week) |
The cochlea is absent, normal, dilated or hypoplastic vestibule, and the system of semicircular canals, often - dilated internal auditory canal, most often - normal aqueduct of the vestibule |
| General cavity (4th week) | The cochlea and vestibule are a single space without internal architecture, a normal or deformed system of semicircular canals, or its absence; the internal auditory canal is more often widened than narrowed; most often – normal aqueduct of the vestibule |
| Incomplete separation type II (5th week) |
The cochlea is represented by a single cavity without internal architecture; expanded vestibule; most often – an enlarged internal auditory canal; absent, enlarged or normal system of semicircular canals; normal aqueduct of the vestibule |
| Cochlear hypoplasia (6th week) | Clear separation of cochlear and vestibular structures, cochlea in the form of a small bubble; absence or hypoplasia of the vestibule and semicircular canal system; narrowed or normal internal auditory canal; normal aqueduct of the vestibule |
| Incomplete separation, type II (Mondini anomaly) (7th week) | Cochlea with 1.5 whorls, cystically dilated middle and apical whorls; the size of the cochlea is close to normal; slightly expanded vestibule; normal system of semicircular canals, expanded aqueduct of the vestibule |
Considering the above modern ideas about the types of cochleovestibular disorders, we use the classifications of R.K. Jackler and L. Sennaroglu, as the most consistent with the findings encountered in their own practice.
Taking into account the small number of patients operated on, one case of successful CI for inner ear malformation is presented below.
Case from practice.
In March 2007, the parents of patient K., born in 2005, came to the St. Petersburg Research Institute of ENT with complaints about the child’s lack of reaction to sounds and lack of speech. During the examination, a diagnosis was made: Chronic bilateral sensorineural hearing loss of IV degree, congenital etiology. Secondary receptive disorder expressive speech. Consequences of intrauterine pregnancy cytomegalovirus infection, intrauterine damage to the central nervous system. Residual organic damage to the central nervous system. Left-sided spastic upper monoparesis. Aplasia of the first finger of the left hand. Dysplasia hip joints. Spasmodic torticollis. Pelvic dystopia hypoplastic right kidney. Delayed psychomotor development.
According to the conclusion of a child psychologist, the child’s cognitive abilities are within age norm, intelligence is preserved.
The child received binaural hearing aids with heavy-duty hearing aids, without effect. According to the audiological examination, short-latency auditory evoked potentials were not recorded at a maximum signal level of 103 dB, and otoacoustic emissions were not recorded on both sides.
When conducting game audiometry in hearing aids, reactions to sounds with an intensity of 80-95 dB in the frequency range from 250 to 1000 Hz were revealed.
CT temporal bones revealed the presence of a bilateral anomaly of cochlear development in the form of incomplete division of type I (Table 4). Moreover, this statement is true for both the left and right ears, despite the seemingly different picture (Fig. 1).
Rice. 1. CT data of patient K.
Note: So, on the right (1) the cochlea is represented by a small cavity, the maximum size of which is no more than 5 mm, the vestibule and semicircular canals are absent. On the left (2) the cochlea is represented by a single cavity without internal architecture, the presence of an expanded vestibule is noted (Fig. 2, arrow); expanded system of semicircular canals (Fig. 3, arrow). 
Fig.2. Extended vestibule on the left
Rice. 3. Enlarged and deformed system of semicircular canals on the left
After the examination, the patient underwent CI on the left ear using the classical approach through anthromastoidotomy and posterior tympanotomy, with the introduction of an electrode through a cochleostomy. For the operation, a special shortened electrode (Med-El, Austria) was used, having a working length of the active electrode of about 12 mm, specially designed for use in cases of anomaly or ossification of the cochlea.
Despite the intact auditory ossicles and stapedius muscle tendon, acoustic reflexes from the stapedius muscle were not recorded during the operation. However, when performing neural response telemetry, clear responses were obtained when 7 out of 12 electrodes were stimulated.
Postoperative transorbital radiography of the cochlea revealed that the active electrode of the implant is located in the common cavity (Fig. 4, arrow), taking the shape of an ideal circle. 
Rice. 4. Transorbital radiography. Shortened electrode in a common cavity.
During a control audiological examination one year after surgery, the patient was found to have reactions in the free sound field to sounds with an intensity of 15-20 dB in the frequency range from 250 to 4000 Hz. The patient’s speech is represented by one- and two-syllable words (“mom”, “give”, “drink”, “kitty”, etc.), a simple phrase of no more than two one- or two-syllable words. Considering that the patient’s age at the time of the re-examination was less than 3 years, the results of auditory-speech rehabilitation in this case should be considered excellent.
Conclusion
The modern classification of developmental anomalies of the inner ear not only gives an idea of the diversity of such pathology and the time of occurrence of the defect during intrauterine development, but is also useful in determining the indications for cochlear implantation and in the process of choosing tactics for intervention. The observation presented in the work allows us to evaluate the possibilities of cochlear implantation as a means of rehabilitation in difficult cases, expands the understanding of indications for implantation.
Literature
- Jackler R.K. Congenital malformations of the inner ear: a classification based on embryogenesis//R.K. Jackler, W.M. Luxford, W.F. House/ Laryngoscope. – 1987. – Vol. 97, no. 1. – P. 1 – 14.
- Jackler R.K. The large vestibular aqueduct syndrome//R.K. Jackler, A. De La Cruz/ Laryngoscope. – 1989. – Vol. 99, No. 10. – P. 1238 – 1243.
- Marangos N. Dysplasien des Innenohres und inneren Gehörganges//N. Marangos/HNO. – 2002. – Vol. 50, no. 9. - P. 866 – 881.
- Sennaroglu L. A new classification for cochleovestibular malformations//L. Sennaroglu, I. Saatci/Laryngoscope. – 2002. – Vol. 112, No. 12. – P. 2230 – 2241.
- Siebenmann F. Grundzüge der Anatomie und Pathogenese der Taubstummheit// F. Siebenmann/Wiesbaden: J. F. Bergmann; 1904. – 76s.
- Stellenwert der MRT bei Verdacht auf Innenohrmissbildung//S. Kösling, S. Jüttemann, B. Amaya et al. / Fortschr Röntgenstr. – 2003. – Vol. 175, No. 11. – S. 1639 – 1646.
- Terrahe K. Missbildungen des Innen- und Mittelohres als Folge der halidomidembryopathie: Ergebnisse von Röntgenschichtuntersuchungen//K. Terrahe/Fortschr Röntgenstr. – 1965. – Vol. 102, No. 1. – P. 14.
V.E. Kuzovkov, Yu.K. Yanov, S.V. Levin
St. Petersburg Research Institute of Ear, Throat, Nose and Speech
(Director - Honored Doctor of the Russian Federation, Prof. Yu.K. Yanov)
Cochlear implantation (CI) is currently generally recognized in world practice and the most promising direction for the rehabilitation of persons suffering from high-grade sensorineural hearing loss and deafness, with their subsequent integration into the hearing environment. In modern literature, the issues of classification of anomalies of the development of the inner ear are widely covered, including in relation to CI, and surgical techniques for performing CI for this pathology are described. The world experience of CI in persons with developmental anomalies of the inner ear spans more than 10 years. At the same time, there are no works on this topic in the domestic literature.
At the St. Petersburg Research Institute of Ear, Throat, Nose and Speech, for the first time in Russia, CI began to be performed on people with developmental anomalies of the inner ear. Three years of experience in such operations, the presence of successful results of such interventions, as well as an insufficient amount of literature on this issue, served as the reason for carrying out this work.
Classification of developmental anomalies of the inner ear. Current state of the issue.
With the advent of the late 80's - early 90's. high-resolution computed tomography (CT) and magnetic resonance imaging (MRI), these techniques have become widely used for diagnosing hereditary hearing loss and deafness, especially when determining indications for CI. With the help of these progressive and highly accurate techniques, new anomalies were identified that did not fit into the existing classifications of F. Siebenmann and K. Terrahe. As a result, R.K. Jackler proposed a new classification, expanded and modified by N. Marangos and L. Sennaroglu. However, it should be noted that MRI in particular currently reveals such fine detail that the malformations detected can be difficult to classify.
In his classification of developmental anomalies of the inner ear, based on conventional radiography and early CT data, R.K. Jackler took into account the separate development of the vestibular semicircular and vestibular cochlear parts of a single system. The author suggested that various types of anomalies appear as a result of a delay or disruption of development at a certain stage of the latter. Thus, the types of malformations detected are correlated with the time of disruption. Later, the author recommended classifying combined anomalies as category A, and suggested a connection between such anomalies and the presence of an expanded aqueduct in the vestibule (Table 1).
Table 1
Classification of developmental anomalies of the inner ear according to R.K.Jackler
Cochlear aplasia or malformation |
|
POSSIBLE presence of an expanded aqueduct of the vestibule |
|
Normal snail |
|
|
Thus, items 1 - 5 of categories A and B represent isolated developmental anomalies. Combined anomalies falling into both categories should be classified as category A in the presence of an expanded vestibular aqueduct. According to R.K. Jackler, S. Kösling made the statement that isolated anomalies represent not only a deformation of one structural unit of the inner ear, but can be combined with anomalies of the vestibule and semicircular canals, as well as with vestibular dysplasia and an enlarged aqueduct of the vestibule.
The N. marangos classification includes incomplete or aberrant development of the labyrinth (Table 2, item 5).
Table 2
Classification of developmental anomalies of the inner ear according toN. Marangos
Subgroup |
|
A |
|
IN |
|
WITH |
X-linked hearing loss |
Anomalies in hereditary syndromes |
Thus, four categories (A-D) of inner ear malformations are described. The author considers the aqueduct of the vestibule to be dilated if the interosseous distance in the middle part exceeds 2 mm, while other authors give a figure of 1.5 mm.
L. Sennaroglu differentiates 5 main groups (Table 3): anomalies of the development of the cochlea, vestibule, semicircular canals, internal auditory canal and aqueduct of the vestibule or cochlea.
Table 3
Main groups and configurations of cochleovestibular anomalies according toL. Sennaroglu
Main groups |
Configuration |
Cochlear abnormalities |
Michel anomaly / cochlear aplasia / common cavity/ incomplete separation type I / cochlear hypoplasia / incomplete separation type II / normal cochlea |
Vestibular abnormalities |
The vestibule: |
Anomalies of the semicircular canals |
Absence/hypoplasia/increased size |
Anomalies of the internal auditory canal |
Absent/narrow/extended |
Anomalies of the aqueducts of the vestibule and cochlea |
Advanced/Normal |
Cochlear malformations (Table 4) were divided by the author into six categories according to the degree of severity, depending on the time of disruption of the normal course of embryonic development. This classification of cochlear malformations includes an incomplete separation of types I and II.
Table 4
Classification of cochlear anomalies according to the time of disruption of intrauterine development according toL. Sennaroglu
Cochlear malformations |
Description |
Michel Anomaly (3rd week) |
Complete absence of cochleovestibular structures, often - aplastic internal auditory canal, most often - normal aqueduct of the vestibule |
Cochlear aplasia (end of 3rd week) |
The cochlea is absent, normal, dilated or hypoplastic vestibule, and the system of semicircular canals, often - dilated internal auditory canal, most often - normal aqueduct of the vestibule |
General cavity (4th week) |
The cochlea and vestibule are a single space without internal architecture, a normal or deformed system of semicircular canals, or its absence; the internal auditory canal is more often widened than narrowed; most often - normal aqueduct of the vestibule |
Incomplete separation type II (5th week) |
The cochlea is represented by a single cavity without internal architecture; expanded vestibule; most often - an enlarged internal auditory canal; absent, enlarged or normal system of semicircular canals; normal aqueduct of the vestibule |
Cochlear hypoplasia (6th week) |
Clear separation of cochlear and vestibular structures, cochlea in the form of a small bubble; absence or hypoplasia of the vestibule and semicircular canal system; narrowed or normal internal auditory canal; normal aqueduct of the vestibule |
Incomplete separation, type II (Mondini anomaly) (7th week) |
Cochlea with 1.5 whorls, cystically dilated middle and apical whorls; the size of the cochlea is close to normal; slightly expanded vestibule; normal system of semicircular canals, expanded aqueduct of the vestibule |
Taking into account the above modern ideas about the types of cochleovestibular disorders, we use the classifications of R.K. Jackler and L. Sennaroglu, as the most consistent with the findings encountered in their own practice.
Taking into account the small number of patients operated on, one case of successful CI for inner ear malformation is presented below.
Case from practice.
In March 2007, the parents of patient K., born in 2005, came to the St. Petersburg Research Institute of ENT with complaints about the child’s lack of reaction to sounds and lack of speech. During the examination, a diagnosis was made: Chronic bilateral sensorineural hearing lossIVdegree, congenital etiology. Secondary receptive and expressive language disorder. Consequences of intrauterine cytomegalovirus infection, intrauterine damage to the central nervous system. Residual organic damage to the central nervous system. Left-sided spastic upper monoparesis. AplasiaIfinger of the left hand. Hip dysplasia. Spasmodic torticollis. Pelvic dystopia of the hypoplastic right kidney. Delayed psychomotor development.
According to the conclusion of a child psychologist, the child’s cognitive abilities are within the age norm and his intelligence is preserved.
The child received binaural hearing aids with heavy-duty hearing aids, without effect. According to the audiological examination, short-latency auditory evoked potentials were not recorded at a maximum signal level of 103 dB, and otoacoustic emissions were not recorded on both sides.
When conducting game audiometry in hearing aids, reactions to sounds with an intensity of 80-95 dB in the frequency range from 250 to 1000 Hz were revealed.
CT scan of the temporal bones revealed the presence of bilateral anomalies of the cochlea in the form of incomplete separationItype (Table 4). Moreover, this statement is true for both the left and right ears, despite the seemingly different picture (Fig. 1).
After the examination, the patient underwent CI on the left ear using the classical approach through anthromastoidotomy and posterior tympanotomy, with the introduction of an electrode through a cochleostomy. For the operation, a special shortened electrode was used (Med- El, Austria), having a working length of the active electrode of about 12 mm, specially designed for use in cases of anomaly or ossification of the cochlea.
Despite the intact auditory ossicles and stapedius muscle tendon, acoustic reflexes from the stapedius muscle were not recorded during the operation. However, when performing neural response telemetry, clear responses were obtained when 7 out of 12 electrodes were stimulated.
Postoperative transorbital radiography of the cochlea revealed that the active electrode of the implant is located in the common cavity (Fig. 4, arrow), taking the shape of an ideal circle.
During a control audiological examination one year after surgery, the patient was found to have reactions in the free sound field to sounds with an intensity of 15-20 dB in the frequency range from 250 to 4000 Hz. The patient’s speech is represented by one- and two-syllable words (“mom”, “give”, “drink”, “kitty”, etc.), a simple phrase of no more than two one- or two-syllable words. Considering that the patient’s age at the time of the re-examination was less than 3 years, the results of auditory-speech rehabilitation in this case should be considered excellent.
Conclusion
The modern classification of developmental anomalies of the inner ear not only gives an idea of the diversity of such pathology and the time of occurrence of the defect during intrauterine development, but is also useful in determining the indications for cochlear implantation and in the process of choosing tactics for intervention. The observation presented in the work allows us to evaluate the possibilities of cochlear implantation as a means of rehabilitation in difficult cases, and expands the understanding of the indications for implantation.
Literature
- Jackler R.K. Congenital malformations of the inner ear: a classification based on embryogenesis//R.K. Jackler, W.M. Luxford, W.F. House/ Laryngoscope. - 1987. - Vol. 97, no. 1. - P. 1 - 14.
- Jackler R.K. The large vestibular aqueduct syndrome//R.K. Jackler, A. De La Cruz/ Laryngoscope. - 1989. - Vol. 99, No. 10. - P. 1238 - 1243.
- Marangos N. Dysplasien des Innenohres und inneren Gehörganges//N. Marangos/HNO. - 2002. - Vol. 50, no. 9. - P. 866 - 881.
- Sennaroglu L. A new classification for cochleovestibular malformations//L. Sennaroglu, I. Saatci/Laryngoscope. - 2002. - Vol. 112, No. 12. - P. 2230 - 2241.
- Siebenmann F. Grundzüge der Anatomie und Pathogenese der Taubstummheit// F. Siebenmann/Wiesbaden: J. F. Bergmann; 1904. - 76s.
- Stellenwert der MRT bei Verdacht auf Innenohrmissbildung//S. Kösling, S. Jüttemann, B. Amaya et al. / Fortschr Röntgenstr. - 2003. - Vol. 175, No. 11. - S. 1639 - 1646.
- Terrahe K. Missbildungen des Innen- und Mittelohres als Folge der halidomidembryopathie: Ergebnisse von Röntgenschichtuntersuchungen//K. Terrahe/Fortschr Röntgenstr. - 1965. - Vol. 102, No. 1. - P. 14.
