EAR

From Big Medical Encyclopedia

EAR [auris; synonym: preddverno-ulit-kovy body (organum vestibulococh-leare, PNA), an organ of equilibrium and hearing (organon status et auditus, JNA), an acoustic organ (organon auditus, B NA)] — an acoustic organ and balances at vertebrate animals and the person.

Comparative anatomy. The inner ear at ancestors of vertebrata was formed of bodies of a sideline (see Fish). Fishes have well developed vestibular labyrinth, a structure to-rogs similarly for all classes of vertebrata, and cochlear — is in embryo. The middle ear appears at amphibiouses in connection with transition to a land way of life. At reptiles the structure of a snail becomes complicated and outside acoustical pass forms. At mammals the ear reaches the highest development — forms spiral (kortiyev) body, the three-membered chain of acoustical stones is formed, the auricle develops. The distinctions in a structure of an ear of mammals connected with adaptation to air, underground and water habitats are noted. Special type of a structure of an acoustic organ reckon, the using ultrasonic orientation and echolocation (shrews, rats, bats, seals, dolphins). The reduction of an auricle and the related muscles is characteristic of anthropoids and the person. At the same time the shape of curls of an auricle becomes complicated and the lobe of an ear is formed (a segment of an auricle, T.).

Embryology. An inner, middle and outside ear develop from various rudiments. Approximately the ZUG weeks embryo has an acoustical placode in the form of a thickening of an ectoderm on both parties of a rhombencephalon. Plunging into a mesenchyma, and then otshnurovyvayas from an ectoderm, it turns consistently into an acoustical pole and an acoustical bubble, to-ry is a rudiment of a webby labyrinth. On 5 — the 6th week of embryonic development semicircular channels and a cochlear channel grow from an acoustical bubble. In the same time nerve knots of an eighth cranial nerve are formed. The cartilaginous capsule develops in circles of a webby labyrinth. As a result of its ossification the bone labyrinth forms. Tympanic cavities have ento a derma a lny origin. The drum cavity and an Eustachian tube develop from the first pharyngeal pocket representing deepening of a wall of a throat of an embryo between I and II branchiate arches (see. Visceral skeleton). In a mesenchyma of these arches acoustical stones are put. Outside acoustical pass is derivative the I branchiate furrow, and the membrane separating this furrow from a rudiment of a drum cavity will be transformed to a tympanic membrane. The auricle forms from group of ear hillocks, to-rye are formed by fabrics I and II of branchiate arches. The structural relations of elements of an ear develop generally by the end of the 4th month of the pre-natal period. The sizes of an inner ear and a drum tympanic cavity at the newborn correspond to that at adults, and the sizes of an outside ear continue to increase after the birth.

Anatomy. The ear is located in temporal area of the head (see). Distinguish an outside ear (see), a cut consists of an auricle and outside acoustical pass; the middle ear (see) including a drum cavity, an Eustachian tube (see. An acoustical pipe) and mastoidal appendages (see the Mastoid); the inner ear (see) presented vestibular and cochlear by labyrinths (fig). An outside and middle ear form the device of catching and carrying out sound waves. In


Fig. The diagrammatic representation of a frontal section through an ear: 1 — a tympanic membrane; 2 — a temporal bone; 3 — a drum cavity; 4 — the semicircular channel; 5 — a snail; 6 — an Eustachian tube, 7 — acoustical stones (a hammer, an anvil, a stirrup); 8 — outside acoustical pass; 9 — an auricle.

an inner ear there are sound receptors and receptors of the statokinetic analyzer perceiving changes of position of a body in space.

The auricle consists of the elastic cartilage of a funneled form covered with skin. Only its lower site (a so-called lobe of an ear) is deprived of a cartilage. The sizes and a shape of an auricle are individually changeable. Outside acoustical pass consists of the cartilaginous part which is continuation of a cartilage of an auricle, and the bone part formed by a drum part of a temporal bone. In the depth of it there is a tympanic membrane (see) separating an outside ear from an average.

The middle ear almost entirely is located in a pyramid of a temporal bone. Its main part is the drum cavity which is reported in front by means of an Eustachian tube with a nasopharynx, behind — with a mastoidal cave. The tympanic cavity is covered by a mucous membrane, edges forms folds and deepenings. On a medial wall of a drum cavity there are windows of a threshold and a snail conducting in an inner ear. In a drum cavity acoustical stones — the hammer, an anvil and a stirrup connected among themselves by joints are located. The long shoot of a hammer is connected with a tympanic membrane, and the basis of a stirrup enters a window of a threshold. Sound waves but system a tympanic membrane — a chain of acoustical stones are transferred to a perilympha of an inner ear.

The inner ear represents system of the cavities and channels which are reported among themselves. Between components its bone and webby the slit-like space is available labyrinths, a cut contains liquid — a feather a lymph. The webby labyrinth is filled by an endolymph. The middle part of a bone labyrinth forms a threshold (vestibulum), from to-rogo the bone channel of a snail, and behind — front, back and lateral semicircular channels in front departs. The webby labyrinth forms in anticipation of elliptic (utricle) and spherical sacks. In walls of these sacks there are spots, in to-rykh receptors of the statokinetic analyzer are stuffed up (see the Otolitovy device). The lymphatic channel originates Endo from both sacks, to-ry comes to a back surface of a pyramid of a temporal bone. In an elliptic sack five openings of front, back and lateral semicircular channels open. In their expanded ends (ampoules) combs where the receptors perceiving changes of position of a body at the movement are localized are located ampullar ". The touch epithelium of spots of a threshold and ampullar combs forms synapses with dendrites of cells of a predoor node preddverno-ulit-kovogo a nerve (see). The spherical sack by means of the connecting channel is reported with a cochlear channel, to-ry passes throughout the bone channel of a snail. This channel separates from perilymphangeal space by means of predoor and spiral membranes. On a spiral membrane is located kortiyev body (see), in Krom there are sensory acoustical perceiving cells. Sound irritations are transferred to fibers of an eighth cranial nerve, on Krom impulses are carried out to predoor and cochlear kernels of a metencephal (see. Vestibular analyzer; Acoustical centers, ways).

Blood supply, a likhmfoottok,

an innervation of an ear — cm. Inner ear, Outside ear, Middle ear.

Methods of inspection. Inspection of the patient with a disease At. begin with clarification of the anamnesis (see). Pay attention to the postponed and associated diseases, presence of the prof. of vrednost — vibrations (see), noise (see), etc. At a sonitus (see), dizziness (see) find out whether they are constant or passing. At suppuration from At. specify its duration, frequency, character of pus whether there was it earlier, whether treatment, etc. was carried out. Then make external examination of an auricle, outside acoustical pass and a mastoid.

Feeling and pressing on a mastoid and a trestle, define whether there is no morbidity; then palpate area limf, nodes on a neck, a mastoid and ahead of outside acoustical pass. (And at its absence and a drum cavity) make an otoskopiya for clarification of a condition of outside acoustical pass and a tympanic membrane (see), at a cut reveal retraction of a tympanic membrane, change of its color, existence of perforation, hems, deposits of salts of calcium, etc. Mobility of a tympanic membrane is investigated by means of a special pneumatic funnel (see Zigle a funnel). Apply ear inflation, and also an ear manomet-riya to a research of passability of an Eustachian tube (see Valjsaljva experience, Mano-metriya ear, Ear inflation). A research of hearing for the purpose of definition of its sharpness, extent of decrease, clarification of character and localization of the process which caused a hearing impairment make by means of the speech, tuning forks and the audiometer (see Audiometriya, Weber experience, Zhelle experience, Iiolittsera — Federi-chi experience, Rinne experience, Hearing, Shva-bakha experience). About disturbances of functions of a vestibular mechanism judge by existence of a spontaneous nystagmus (see), disorders of balance (see. Vestibular reactions), and also but to data of experimental tests — rotary, caloric, pneumatic and galvanic (see Vestibulometriya, Otolitovy anna r am, Elektronistagmografiya).

At diseases At. widely apply rentgenol. research of a temporal bone. Define localization and prevalence by a X-ray analysis patol. process, and it is frequent also the nature of a disease. Roentgenograms carry out in side (according to Schueller), axial (according to Maier) and a braid (across Stenver-su) projections. For obtaining the image of an average At. (a drum cavity) use a tomography (see) in a direct (back) projection.

Pathology includes malformations, damages and diseases.

Defects also I am developed. Various malformations outside meet At., quite often combined with an underdevelopment of a middle and inner ear (see. Inner ear, Outside ear, Middle ear).

Damage I. From injuries At. bruises with injury of an auricle are more often observed, to-rye freezing injuries (see) and burns (see) outside can be complicated by an othematoma (see) and a perichondritis (see), At. After injuries and burns cicatricial atresias and strictures of outside acoustical pass can be observed. As a result of strong blow fractures of a temporal bone with damage of outside acoustical pass, average are possible At., labyrinth. Due to especially expressed sensitivity At. to sounds, vibration and differences of atmospheric pressure can be observed also acoustic injury (see), a vibrotrauma (see) and a barotrauma (see) fish soup.

Fighting damages At. by the form the injuring agent wounds cold weapon (cut, chipped wounds) divide into gunshot wounds (fragmental and bullet), bruises stupid weapon (most often bruises), thermal defeats — burns, freezing injuries and so-called contusional defeats — a barotrauma, an acoustic injury, an aktseler about an injury (see).

According to N. I. Kostrov and with - a bus (1979), during the Great Patriotic War wounded with fighting damages At. made 26,3% of total number of wounded with damage of JIOP bodies; at wounded in At., according to V. F. Und-rits (1951), injuries of a temporal bone met in 16% of cases, from them at 13,7% of victims the getting wounds of a skull were noted. In most cases wounds At. were combined with damage of scales of a temporal bone, occipital and malar bones, top and bottom jaw, eye-socket. Injuries of a brain, a parotid gland, an eye, a throat, a throat were quite often noted.

From fighting damages outside At. bruises with development of an othematoma, separations or crush of an auricle (partial or full), gaps or crush of walls of outside acoustical pass, defects of soft tissues of area of a mastoid and surface bone layers of a shoot, etc. are often observed. At these injuries function U quite often suffers., there are cosmetic defects of an auricle, an atresia of outside acoustical pass, an anchylosis of a temporal and mandibular joint, paresis and paralyzes of a facial nerve. Injuries of a middle and inner ear lead to direct or indirect dysfunction of vestibular and acoustical analyzers. Victims have a sonitus, hearing goes down, sometimes up to full deafness, disorders of balance, a spontaneous nystagmus and vegetative reactions are observed. Contusional defeats At. can be followed by the local damages caused by immediate effect on At. a blast wave (see Explosion). Hemorrhages in a tympanic membrane, its gap with insignificant bleeding from an ear, the defeat of a labyrinth leading to deafness (to a thicket bilateral), vestibulove-getativny frustration result (see. Vestibular symptom complex).

First aid (see. First aid) at wounds At. consists in imposing of an aseptic bandage on a wound for what use a first-aid dressing kit (see a dressing first-aid kit). Apply a compressing bandage the bleeding wound. At contusional defeats with a loss of consciousness it is necessary to prevent aspiration of emetic masses.

The first medical and qualified surgical aid at the proceeding bleeding from an ear consists in a hard tamponade of outside acoustical pass. The bleeding outside wound is tamponed or impose a ligature on the visible bleeding vessel. The qualified psychoneurological help to contused can be given in MSB (OMO) on condition of strengthening by its psychoneurological group (see. The qualified medical care, First medical assistance).

The specialized help (see. Specialized medical care) at damage outside At. render in hospital for lightly wounded, at damage of average and internal At. — in hospital for wounded in the head, a neck, a backbone. At the same time carry out a final stop of bleeding with use of all of receptions possible for this purpose (tamponades, bandagings of vessels in a wound, bandagings of the main vessels, tamponades of a sigmoid sine); surgical treatment of wounds of an ear and the neighboring areas with carrying out perhaps early slukhuluchshayushchy operations on a middle ear; prevention and treatment of inflammatory wound complications. Specialized medical aid to contused is rendered in field neurologic hospitals. Slight burns and freezing injuries of an ear treat in hospitals for lightly wounded, heavy — in hospitals for wounded in the head, a neck and a backbone.

The wounded who lost the fighting capacity and working capacity needing in long (more than 2 — 3 months) specialized treatment concerning a separation of an auricle, posttraumatic purulent average otitis, a labyrinthitis, intracranial complications with heavy and permanent disorders of hearing and vestibular function are subject to evacuation in hospital of the back of the country.

The forecast depends on weight and the nature of damage.

Diseases. To the most frequent inflammatory diseases At. otitises belong (with - m. Otitis). Distinguish outside, average and internal otitis (see the Labyrinthitis). Inflammatory process in outside At. can be limited (furuncle) or diffusion; the last is caused in some cases by parasitic fungi (see the Otomycosis). Average otitis can be acute and chronic. Acute average otitis in most cases comes to an end with recovery, however under unfavorable conditions when purulent inflammatory process of a drum cavity passes on antrum (a mastoidal cave, T.), the bone surrounding it and a bone tissue of a mastoid, it can become complicated antrity (see), a mastoiditis (see) or to pass in hron. form. In an acute stage of average otitis if there is a sharp protrusion of a tympanic membrane and morbidity during the pressing on a mastoid, make a paracentesis for the prevention of these complications meeting at children more often (see). Both at acute, and at chronic purulent average otitis there can be serious complications — a labyrinthitis, meningitis (see), abscess of a brain (see the Brain), sepsis (see), paresis of a facial nerve (see), etc. Most often these complications develop at the chronic purulent attic disease complicated by a cholesteatoma (see the Cholesteatoma of an ear). In these cases an operative measure is shown. Quite often owing to average otitis relative deafness (see) develops since the formed hems, commissures, unions, deposits of salts of calcium in a drum cavity interfere with normal transfer of sound vibrations (see the Tympanosclerosis). Formation of unions in a drum cavity (adhesive process) with the subsequent hearing disorder is observed at a tuboopgita (see). In a crust, time exudative average otitis with a sluggish current, accumulation in a drum cavity of serous liquid is quite often observed, hearing impairment. In these cases usually make a tympanopuncture (see), suck away exudate and enter into a drum cavity a hydrocortisone or himo-tripsinony

Of other diseases At. an otosclerosis (see), labyrinthopathies (see), Menyer's disease meet (see Menyer a disease), neuritis of a preddver-but-cochlear nerve (see), to-rye lead to a sharp hearing impairment up to deafness (see) and to dysfunction of a vestibular mechanism. At education in outside acoustical pass of cerumen impactions or hit to it of foreign bodys (see) them delete by ear irrigation (see). The irradiating pains which are localized in an auricle and outside acoustical pass, and also in people around are often observed At. sites, without any organic changes in them (see the Otalgia).

Operations. Operative measures at diseases At. make in most cases under a local anesthesia (see. And a pesta a ziya local), and at uneasy patients (especially children) — under anesthetic (see). Deformations of auricles, atresias and strictures of outside acoustical pass correct by plastic surgeries (see the Otoplasty). A middle ear operations — an antrotomy, a mastoidotomy, a mastoidektomiya (see the Mastoiditis), carry out radical (obshchepolostny) operation (see Otitis) for the purpose of treatment of purulent process and the prevention life-threatening (e.g., intracranial) complications. In modern a wedge, practice a number of operations on a middle ear for the purpose of improvement of hearing at the relative deafness caused by disturbances of functions of the sound carrying out system apply, to-rye combine under the general name a tympanoplasty (see). Widely various methods of a stapedoplasty allowing to achieve positive takes at treatment of conductive relative deafness at an otosclerosis are implemented into practice. In case of unsuccessful conservative treatment of a disease of Menyer resort to carrying out step-by-step (starting with the least traumatic) operations (see Menyer a disease).

Patient care after operations on At. (see Leaving, for otorhinolaryngological patients) in many respects depends on anesthesia and the nature of operation. In the postoperative period (see), especially at patients with intracranial complications, monitor emergence of dizziness, nausea, vomiting, symptoms of paresis of a facial nerve, behind a condition of a bandage (bleeding), a regularity fiziol. departures. Patients after radical operation on At. and tympanoplasties shall observe a bed rest before the first bandaging, i.e. within 7 — 8 days; before they need to change top coats of a bandage daily. According to indications appoint antibiotics taking into account sensitivity of microflora to them.

Bibliography: Theological L. S.,

and Solntseva G. N. Acoustical system of mammals, M., 1979; In at l -

matte X. Slukhouluchshayushchy operations, the lane with it., M., 1972; e r hectare

ma S. A N. Surgical treatment of chronic purulent attic diseases, L., 1969; N. I. fires, P e in -

with to about y Yu. K. and Gorokhov A. A. Harakter and structure of gunshot wounds Lororganov, Voyen. - medical zhurn., No. 4, page 42, 1979; Kunelskaya V. Ya.

Otomycoses, M., 1968; To at r and sh in and -

l and A. E. Organization of medical care by Lorraneny at stages of medical evacuation, Voyen. - medical zhurn., No. 11, page 7, 1973; The Multivolume guide to otorhinolaryngology, under the editorship of A. G. Likhachev, t. 1 — 2, M., 1960; To It

Mang L. V. Anatomiya, physiology and pathology of acoustic organs and speech, M., 1965; Experience of the Soviet medicine in the Great Patriotic War of 1941 — 1945, t. 8, M., 1951; Palchun V. T., Kaplan S. I. and Voznesensky N. L. Neurologic complications in otorhinolaryngology, M., 1977; Preobra

female N. A. and Patyakin O. K. Stapedectomy and stapedoplasty, M., 1973; Petten B. M. Embryology of the person, the lane with English, page 406, M., 1959; Soldatov I. B., It is real in and G. P. and Hrappo N. S. Vestibular dysfunction, M., 1980;

Theses of the 8th congress of otorhinolaryngologists of the USSR, M., 1982; Temkin Ya. S. Acute otitis and its complications, M., 1955;

Undrits V. F., Temkin Ya. S. and Neumann L. V. Guide to a clinical audiology, M., 1962; F and -

l and L. I. Embriologiya's N of the person, the Atlas, page 511, 531, M., 1976; Zimmerman G. S. Ear and brain, M., 1974.

V. P. Gamov (pathology), Yu. K. Revekoy (soldier.), V. S. Speransky (An.).

Яндекс.Метрика