Hearing examination. Basic methods of hearing research. Additional studies or analyzes

Ear audiometry (akumetry) - a method for determining hearing acuity, in which the degree of susceptibility is assessed auditory analyzer regarding sound waves of different frequency and intensity. Audiometric studies are carried out using special electronic devices (audiometers). In comparison with other methods for determining auditory sensitivity, acumetry allows you to dose the intensity of sound signals. Thus, it is possible to determine the threshold sensitivity of the auditory analyzer to sound vibrations of certain frequencies.

On an outpatient basis, audiometric testing is carried out in soundproof rooms. The test results are presented as a two-dimensional graph, which can be used to determine the degree of hearing loss and the type of hearing loss (conductive or neurosernoral). If necessary, you can conduct a test to check your own auditory sensitivity yourself.

Survey features

Hearing diagnostics, which is carried out in the office of an audiologist and an otolaryngologist, allows you to determine not only the fact of hearing loss, but also the type of pathology in the auditory analyzer. Using an audiometer, a specialist examines the threshold conductivity of bone and air tones. Depending on the methods of recording auditory sensitivity and diagnostic methods, there are several types of audiometry:

• speech - the simplest and most accessible method for studying threshold audibility, in which a specialist determines the degree of speech recognition at different levels of intensity (in decibels);
• tonal - an acoustic examination, during which the audibility of tones of various frequencies and intensities is determined;
• computer - one of the most reliable ways to determine the auditory sensitivity of the sound-conducting and sound-receiving system.

Speech and tone audiometry is one of the subjective methods for studying hearing acuity, since during testing the specialist focuses on the testimony of the patient, who reports whether he hears the given signals (speech) or not. A computerized hearing test involves connecting special electrodes to the patient, which record activity in certain areas of the brain in the event that the auditory analyzer responds to signals coming from outside.

Speech audiometry

How to test hearing at home? In the absence of special equipment that allows you to give and record sound signals of a certain intensity and frequency, you can test the organ of hearing using speech audiometry. This diagnostic method does not require medical equipment and additional accessories. To determine the threshold of auditory sensitivity, the subject will need only the conversational apparatus of an audiometrist.

The test results largely depend not only on the state of the auditory analyzer, but also on the breadth of the subject's vocabulary.

To obtain a more objective assessment of the patient's hearing threshold, the audiometrist should not pronounce individual words, but phrases consisting of a set of simple and understandable words. How should the test be done? It is advisable to perform diagnostics in a room with a minimum amount of extraneous noise. In this case, the subject must sit in the middle of the room on a chair.

The actions of the audiometrist should be as follows:

1. move away from the subject at 2-3 m and say a phrase consisting of at least 7-9 words in a whisper;
2. at a distance of 6 m from the subject, quietly pronounce a set of individual phrases;
3. from a distance of 20 meters, say the phrase in raised tones.

During testing, the audiometrist should always ask whether the subject hears speech from a certain distance or not. In this way, you can approximately find out whether there is a hearing impairment or not.

Interpretation of results

In the absence of disturbances in the operation of the sound-perceiving and sound-conducting system, a person can hear whispered speech and the ticking of a clock, the intensity of which is in the range from 0 to 25 dB. When perceiving sound signals in this interval, there are no ear pathologies. When deciphering the results of speech audiometry, the following nuances are taken into account:

In case of disappointing results, you should seek help from an otolaryngologist. Based on the patient's testimony, he will conduct the necessary audiometric studies, during which he will be able to determine the hearing threshold and the type of hearing loss with high accuracy.

Today, speech audiometry is no longer used to test hearing acuity, but to select and adjust hearing aids during hearing aids.

Self check

How to check your hearing yourself? If you wish, you can check the acuity of your own hearing without the help of strangers. To do this, experts offer to pass a simple test in which you need to honestly answer (yes / no) to several questions:

1. Do you hear the ticking of a clock or a whispered speech?
2. Do you often have problems understanding speech on the phone?
3. Do your friends and relatives complain about the constant asking again?
4. Are you often told that you listen to your TV, music player or radio loudly?
5. can you hear the birds singing outside the window?
6. can you understand whispered speech from a distance of 2 m?
7. Don't you think that most of your interlocutors speak indistinctly?

If, after passing the test, the subject understands that most of the answers do not speak in favor of normal hearing acuity, you should seek help from a specialist.

Important! With the development of infectious diseases associated with damage to the nasal mucosa, hearing acuity naturally decreases, due to blocking of the mouth of the Eustachian tube. If an audiometric test is performed in this state, the results will be unreliable.

Special applications

You can objectively assess the condition of the hearing organ using special applications for phones running on Android or iOS platforms. How to test hearing? To do this, you must pass an audiometric test developed by practicing audiologists and otolaryngologists. Based on the test results, it is possible to determine the degree of audibility and the threshold of auditory sensitivity of receptor cells.

Some of the easiest apps to test your hearing include:

• I. "Hörtest";
• II. "Mimi Hearing Test";
• III. "uHear".

If you don't have a smartphone, you can get tested using personal computer and regular headphones. According to the obtained graphs, it is easy to determine whether the hearing threshold is within the normal range or not.

Why is it important to know about your child's hearing loss as early as possible?

Severe hearing impairment is the reason for the difficulty of adapting a patient with hearing loss in society. This happens primarily due to limited communication with others, as well as disorientation in everyday life and professional activities. It is generally accepted that about 10–15% of the population suffers from congenital or acquired hearing impairments that require correction by means of hearing rehabilitation (hearing aids, CI systems).

Diagnosis of hearing loss in children early age currently pay great attention and consider it one of the most urgent tasks of modern otorhinolaryngology. In patients of this age group, the diagnosis of hearing impairment is especially important from the point of view of social adaptation. Sensorineural (the old name is "neurosensory") hearing loss with high hearing thresholds is the most formidable type of hearing loss in relation to the child's integration into the speech environment. Normally, the formation of speech begins already in the first year of a child's life, which is a fundamental moment in the development of the psyche and intellect. In this regard, objective (that is, not dependent on the patient's participation in the testing procedure) hearing assessment methods are the main, and often the only, criterion for determining further therapeutic and rehabilitation measures.

Diagnosis of hearing in newborns. Audiological neonatal screening. What it is?

A distinctive feature of this screening system is the early detection of children with hearing impairments, and, accordingly, the early start of treatment and rehabilitation measures among hearing-impaired and deaf children.

As a rule, screening examinations are focused on early detection, if it is proved that the detection of a given condition or disease on early stages will contribute to more effective treatment. With regard to the early detection of hearing impairment in newborns and children of the first year of life, this means that timely rehabilitation of hearing in such children will help reduce the proportion of people with persistent hearing impairment, when due to its compensation, almost complete social rehabilitation of such children is achieved, eliminating the need for them. maintenance and training in specialized institutions and giving them the opportunity to become full members of society.

Rice. 1. Structure of a two-stage program for audiological neonatal screening.

Advanced hearing diagnostics. How are hearing impairments diagnosed in children?

The most common group of objective methods for diagnosing hearing is the method of recording auditory evoked potentials (SEPs) of the brain. Currently, a number of types of recording SEPs have received clinical use, namely: electrocochleography (ECoG), recording of short-latency or brainstem auditory evoked potentials (SEPs), mid-latency SEPs, long-latency auditory evoked potentials (LEPs) and recording of the auditory response to constant tones - Auditory Steady State Response - ASSR (in some sources, this technique is called the registration of stationary brain responses). Each technique has its advantages and disadvantages, which determines the choice of a specific test by an audiologist (audiologist - otorhinolaryngologist).

Of the studies listed above, the method of recording ABR for an objective assessment of the level of hearing has become the most widely used. The classical technique involves the use of acoustic clicks as a presented stimulus.

However, this method of recording ABRs is not always informative in relation to patients with high hearing thresholds. First of all, this is due to the fact that the maximum level of the presented stimulus when using acoustic clicks does not exceed 100–105 dB nPs (dB nHL), depending on the equipment used. Secondly, it is impossible not to take into account the differences between the values ​​of the hearing thresholds recorded according to the ABR data and the hearing thresholds obtained from the data of tone threshold (behavioral) audiometry. Thirdly, the wide frequency spectrum of such a stimulus limits the estimation possibility of the method, namely, the acoustic click energy contains the physical characteristics of the frequency range of the cochlea in the range from 1 to 4 kHz, which reduces the tuning quality. hearing aid.

Get information about the so-called. frequency-specific thresholds of sound perception allows the test of recording an auditory response to a constant modulated tone - Auditory Steady - State Response (ASSR).

The auditory evoked response (ASSR) is the brain's response to continuous acoustic stimuli that is optimized for frequency specificity and is more comparable to pure tones than an acoustic click or tone burst.

These modulated tones used to record evoked responses are physically similar to the trill tones used in conventional audiometry. In addition, the system is capable of presenting stimuli in excess of 100 dB (up to 130 dB) nPs (dB nHL). This feature of the method allows testing at all audiometric frequencies and obtaining a evoked response to a stimulus similar in its physical characteristics to those stimuli generated by a tone audiometer (Fig. 2).

Rice. 2. Automatic interpretation of ASSR data - test - construction of an approximate audiogram.
Based modern technology registration and computer processing of the evoked auditory response of the brain to constant acoustic stimuli (ASSR) provides an opportunity to make an objective assessment of the state of the sound-perceiving apparatus at all frequencies of the speech range, including in patients with sensorineural hearing loss with hearing thresholds exceeding 90-100 dB. Based on the data obtained, the possibilities of selection and initial adjustment of hearing aids are expanding, including for young children. In addition, it appears Additional Information for ear selection in cochlear implantation due to data on the preservation of individual frequency zones of the cochlea.

How to prepare a child for a hearing test?

In children under 6 years of age, objective tests are the most informative for assessing auditory function, the result of which does not depend on the child's answers. The most difficult are tests of registration of the auditory potentials of the brain, which are carried out in a state of sleep. In order for the study to turn out in full, it is necessary that the duration of sleep be at least an hour. To this end, the time of the study must be planned taking into account the time of the child's traditional, for example, daytime sleep. On the eve of the study, it is better to put the child to bed as late as possible and wake up early on the day of the study.

How to examine hearing if the child is not sleeping?

If it is not possible to euthanize the child, a hearing test is carried out in a state of medical sleep. This technique is in demand in children with severe neurological disorders and other conditions accompanied by sleep disorders.

To diagnose hearing under anesthesia, it is necessary to undergo a preliminary examination at our Center and then, on the same day, conduct a hearing test.

Attention! The decision to conduct a hearing test in a state of medical sleep is taken only by an AUDIOLOGIST after examining the child and consulting!

Hearing test in children older than 6 years

A traditional hearing test, pure tone audiometry, is performed on children from 6 years of age. This research method is subjective, i.e. the result depends on the interest of the child to be tested.

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These methods include history, physical examination, hearing test (acumetry, audiometry), additional methods examinations (radiography, CT, MRI).

Anamnesis

Patients suffering from hearing loss usually complain of hearing loss, tinnitus, less often - dizziness and headache, irritability, reduced speech intelligibility in noisy environments, and a number of others. Some patients indicate the cause of hearing loss (chronic inflammation of the middle ear, a diagnosis of otosclerosis, a history of skull trauma, activities in industrial noise conditions (mechanical assembly and blacksmith shops, the aviation industry, work in an orchestra, etc.). Of the comorbidities, patients may indicate the presence of arterial hypertension, diabetes mellitus, osteochondrosis cervical spine, hormonal dysfunction, etc.

The purpose of the anamnesis of an audiological patient is not so much to ascertain the fact of hearing loss, but to identify its cause, to establish concomitant diseases that aggravate hearing loss, occupational hazards (noise, vibration, ionizing radiation), and past use of ototoxic drugs.

When talking with the patient, the nature of his speech should be assessed. For example, loud and clear speech indicates the presence of acquired bilateral sensorineural hearing loss in years when the articulatory function of the speech motor apparatus was fully formed. Slurred speech with articulation defects indicates that the hearing loss occurred in the early childhood when the basic speech skills have not yet been formed. Quiet intelligible speech indicates a conductive type of hearing loss, for example, in otosclerosis, when tissue conduction is not impaired and fully provides auditory control of one's own speech. You should pay attention to the "behavioral" signs of hearing loss: the patient's desire to approach the doctor with a better hearing ear, putting his palm to his ear in the form of a mouthpiece, an attentive look fixed on the doctor's lips (lip reading), etc.

Physical examination

Physical examination includes the following techniques and methods: examination, palpation and percussion of the facial and auricular-temporal regions, endoscopy of the ear, examination of the barofunction of the auditory tube, and some others. Endoscopy of the nose, pharynx and larynx is carried out according to the generally accepted method.

At external examination pay attention to the anatomical elements of the face and its appearance: the symmetry of facial expressions, nasolabial folds, eyelids. The patient is offered to bare his teeth, wrinkle his forehead, close his eyes tightly (control of the function facial nerves). Tactile and pain sensitivity is determined by the zones of innervation of the branches trigeminal nerve. When examining the ear region, the symmetry, size, configuration, color, elasticity, state of tactile and pain sensitivity of its anatomical formations are evaluated.

Palpation and percussion. With their help, skin turgor, local and distant pain are determined. When complaining of pain in the ear, deep palpation and percussion are performed in the projection area of ​​the antrum, the platform of the mastoid process, the scales of the temporal bone, the area of ​​the temporomandibular joint and the retromandibular fossa in the area of ​​the parotid salivary gland. The temporomandibular joint is palpated when opening and closing the mouth to detect clicks, crunches and other phenomena indicating the presence of arthrosis of this joint.

Otoscopy. When examining the external auditory canal, pay attention to its width and contents. First, they examine it without a funnel, pulling auricle upwards and backwards (in infants backwards and downwards) and at the same time pushing the tragus anteriorly. The deep sections of the ear canal and the tympanic membrane are examined with the help of an ear funnel and a frontal reflector, while the presence or absence of certain identifying signs of it and pathological changes(retraction, hyperemia, perforation, etc.).

Hearing test

The science that studies the auditory function is called audiology(from lat. audio- I hear), and the clinical direction that deals with the treatment of hearing-impaired people is called audiology(from lat. surditas- deafness).

The hearing test is called audiometry. This method distinguishes the concept acumetry(from Greek. akouo- I listen), which is understood as the study of hearing with live speech and tuning forks. In audiometry, electronic-acoustic devices (audiometers) are used. The responses of the subject (subjective reaction) serve as evaluation criteria: “I hear - I don’t hear”, “I understand - I don’t understand”, “louder - quieter - equally loud”, “higher - lower” according to the tone of the sound test, etc.

The sound pressure equal to 2.10:10,000 microbars (µb), or 0.000204 dynes/cm 2 , at a sound frequency of 1000 Hz, was taken as the threshold value of auditory perception. A value 10 times greater is equal to 1 bela (B) or 10 dB, 100 times greater (×10 2) is 2 B or 20 dB; 1000 times large (×10 3) - 3 B or 30 dB, etc. The decibel as a unit of sound intensity is used in all threshold and suprathreshold audiometric tests related to the concept volume.

In the XX century. for the study of hearing, tuning forks became widespread, the method of using which in otiatry was developed by F. Bezold.

The study of hearing "live" speech

Whispered, colloquial, loud and very loud speech (“cry with a ratchet”) is used as testing speech sounds (words) when the opposite ear is muffled with a Barani rattle (Fig. 1).

Rice. one.

In the study of whispered speech, it is recommended to pronounce the words in a whisper after a physiological exhalation, using the reserve (residual) air of the lungs. In the study of colloquial speech, ordinary speech of medium volume is used. The criterion for assessing hearing in whispered and colloquial speech is distance from the researcher to the subject, from which he confidently repeats at least 8 out of 10 words presented to him. Loud and very loud speech is used for hearing loss of the third degree and is pronounced over the patient's ear.

Hearing test with tuning forks

When studying hearing with tuning forks, a set of tuning forks of different frequencies is used (Fig. 2).

Rice. 2.

When examining hearing with tuning forks, a number of rules must be observed. The tuning fork should be held by the leg without touching the jaws. Do not touch the branches of the auricle and hair. When examining bone conduction, the tuning fork leg is placed on the crown or forehead along the midline (when determining the phenomenon literalization sound a) or on the site of the mastoid process (when determining playing time tuning fork). The leg of the tuning fork should not be pressed too strongly against the tissues of the head, since the resulting pain sensation distracts him from the main task of the study; in addition, it contributes to the accelerated damping of vibrations of the tuning fork branches. It should be borne in mind that sounds of 1000 Hz and above are able to bend around the head of the subject, therefore, with good hearing in the non-examined ear, the phenomenon over-the-air listening. Relistening may also occur in the study of tissue conduction; it occurs when there is a perceptual hearing loss, and the opposite ear either hears normally or has a conductive type of hearing loss, such as cerumen plug or scarring.

With the help of tuning forks, a number of special audiometric tests are carried out for differential diagnosis between perceptual and conductive types of hearing loss. It is advisable to record the results of all acumetric tests carried out using live speech and tuning forks in the form of the so-called auditory passport(Tables 1, 2), which combines five aspects of the study:

1) detection of spontaneous irritation of the sound analyzer according to the SN test ( subjective noise);

2) determination of the degree of hearing loss in relation to live speech according to the SR tests ( whispered speech) and RR ( Speaking). With a high degree of hearing loss, the presence of hearing is determined by the test "cry with a rattle";

3) determination with the help of tuning forks of the sensitivity of the organ of hearing to pure tones during air and tissue conduction of sound;

4) identification of certain correlations between the perception of low and high tones during air and bone conduction of sound for the differential diagnosis of forms of hearing loss;

5) establishing the lateralization of sound by bone conduction to establish the type of hearing loss in the worse hearing ear.

Table 1. Hearing passport in violation of sound conduction

Table 2. Hearing passport for impaired sound perception

SSH test reveals the presence of irritation of the peripheral nervous apparatus of the organ of hearing or the state of excitation of the auditory centers. In the hearing passport, the presence of tinnitus is marked with a “+” symbol.

Living speech research. This study is carried out in the absence of extraneous noise. The examined ear is directed towards the examiner, the other ear is tightly closed with a finger. The results of the live speech study are recorded in the auditory passport in meters in multiples of 0.5: 0; “at cancer”, which means “hearing at the shell”; 0.5; one; 1.5 m, etc. The result is recorded at the distance from which the subject repeats 8 out of 10 named words.

When examining hearing with tuning forks, the tuning fork is brought to the outer ear canal branch plane at a distance of 0.5-1 cm with a frequency of once every 5 s. The entry in the passport is made with the same multiplicity, i.e. 5 s; 10 s; 15 s, etc. The fact of hearing loss is established in cases where the time of sound perception is shortened by 5% or more relative to passport norm tuning fork.

Evaluation criteria for tuning fork tests of a typical hearing passport

• With air conduction of sound:
• conductive (bass) hearing loss: a decrease in the duration of perception of the tuning fork C 128 with near-normal perception of the tuning fork C 2048;
• perceptual (treble) hearing loss: near-normal time of perception of a tuning fork C 128 and a decrease in the duration of perception of a tuning fork from 2048.
• With tissue (bone) conduction of sound (only C 128 tuning fork is used):
• conductive hearing loss: normal or increased duration of sound perception;
• perceptual hearing loss: a decrease in the duration of sound perception.

Allocate also mixed type hearing loss, at which there is a shortening of the perception time of the bass (C 128) and treble (C 2048) tuning forks with air sound conduction, and the bass tuning fork with tissue sound conduction.

Criteria for evaluating tuning fork tests

Schwabach experience (1885). Classic variant: the leg of the sounding tuning fork is applied to the crown of the subject until he stops perceiving the sound, after which the examiner immediately applies it to his crown (it is assumed that the examiner should have normal hearing); if the sound is not heard, this indicates the normal hearing of the subject, if the sound is still perceived, then the subject's bone conduction is "shortened", which indicates the presence of perceptual hearing loss.

Weber's experience(1834). The leg of the sounding tuning fork is applied along the midline to the forehead or crown, the subject reports the presence or absence of lateralization of the sound. With normal hearing or with its symmetrical decrease, the sound will be felt "in the middle" or "in the head" without a clear lateralization. If the sound conduction is disturbed, the sound is lateralized into the worse hearing ear, if sound perception is impaired, it is lateralized into the better hearing ear.

Rinne experience(1885). With the help of C 128 or C 512, the sounding time of the tuning fork during air conduction is determined; then determine the sounding time of the same tuning fork during tissue conduction. Normally and with sensorineural hearing loss, the duration of sound perception with air sound conduction is longer than with tissue sound conduction. In this case it is said that " Rinne's experience is positive”, and in the auditory passport this fact is noted in the corresponding cell with a “+” sign. In the case when the sounding time with tissue sound conduction is longer than the sounding time with air conduction, they say that " Rinne's experience is negative", And a sign is affixed in the auditory passport"-". A positive "Rinne" is typical of normal hearing with normal air and bone conduction times. It is also positive in sensorineural hearing loss, but at lower time values. Negative "Rinne" is typical for a violation of sound conduction. In the absence of sound perception through air sound conduction, one speaks of an “infinitely negative Rinne”, in the absence of bone conduction, one speaks of an “infinitely positive Rinne”. “False negative Rinne” is noted when listening through the bone with the other ear if the hearing in this ear is normal, and there is a pronounced sensorineural hearing loss in the examined ear. In this case, to study hearing, a healthy ear is muffled with a Barani ratchet.

The Jelle experience(1881). Designed to determine the presence or absence of mobility of the base of the stirrup and is mainly used to detect ankylosis of the stirrup in otosclerosis. The experiment is based on the phenomenon of a decrease in the volume of a sounding tuning fork during bone conduction during an increase in pressure in the external auditory canal. For the experiment, a low-frequency tuning fork with a long sounding time and a Politzer cylinder with a rubber tube with an olive pointed at its end are used. The olive, selected according to the size of the external opening of the auditory canal, is firmly inserted into the external auditory canal, and the sounding tuning fork is placed with a handle on the site of the mastoid process. If the sound gets quieter, talk about " positive» experience of Gellet, if it does not change, then the experience is defined as « negative". The corresponding symbols are put down in the auditory passport. The negative experience of Gellet is observed in the dissociation of the auditory ossicles as a result of trauma, perforations of the tympanic membrane and obliteration of the windows of the ear labyrinth. Instead of a tuning fork, you can use the bone phone of an audiometer.

Tone threshold audiometry

Tonal threshold audiometry is a standard, generally accepted method for studying auditory sensitivity to "pure" tones in the range of 125-8000 (10,000) Hz for air conduction of sound and in the range of 250-4000 Hz for bone conduction of sound. For this purpose, special sound generators are used, the scales of which are calibrated in dB. Modern audiometers equipped with built-in computer software which allows you to record the study with display on the display tone audiogram and its fixation in a "hard copy" on a special form using a printer indicating protocol data. For the right ear on the form of a tone audiogram, red is used, for the left - blue; for air conduction curves, a solid line; for bone conduction, a dotted line. When conducting tonal, speech and other types of audiometric examination, the patient must be in a sound-damped chamber (Fig. 3). Each audiometer is additionally equipped with a generator of noise narrowband and broadband spectra for conducting research with the masking of an unexplored ear. To study air conduction, specially calibrated headphones are used; for bone conduction - "bone phone" or a vibrator.

Rice. 3. Audiometer; in the background is a sound-damped mini-camera

In addition to the threshold tone audiogram, modern audiometers contain programs for many other tests.

With normal hearing, the curves of air and bone conduction pass near the threshold line with a deviation at different frequencies within ± 5-10 dB, but if the curves fall below this level, this indicates a hearing impairment. There are three main types of changes in the tone threshold audiogram: ascending, descending And mixed(Fig. 4).

Rice. 4. The main types of tone threshold audiograms: I - ascending in violation of sound conduction; II - descending in violation of sound perception; III - mixed in violation of sound conduction and sound perception; RU - cochlear reserve, indicating the potential for hearing to be restored to the level of bone conduction, provided that the cause of hearing loss is eliminated

suprathreshold audiometry

Above-threshold audiometry includes audiometric tests in which test tones and speech signals exceed the threshold of hearing sensitivity. With the help of these samples, the following goals are achieved: identifying slew rate phenomenon And adaptation reserves hearing organ, definition level of hearing discomfort, degree speech intelligibility And noise immunity, a number of other functions of the sound analyzer. For example, using the Luscher-Zviklotsky test, they determine differential intensity threshold at differential diagnosis between conductive and perceptual types of hearing loss. This test is presented as a standard test in any modern audiometer.

Speech audiometry

In this test, separate specially selected words containing low and high frequency formants are used as testing sounds. The result is evaluated by the number of correctly understood and repeated words as a percentage of the total number of words presented. On fig. 5 shows examples of speech audiograms for various types of hearing loss.

Rice. five. Speech audiograms for various types of hearing loss: 1 - curve for conductive hearing loss; 2 — a curve at a cochlear form of relative deafness; 3 — a curve at the mixed form of relative deafness; 4 — a curve at the central type of relative deafness; a, b — different positions of the speech intelligibility curve in the conductive type of hearing loss; c, d — downward deviations of the curves with a decrease in USD (in the presence of FUNG)

Spatial Hearing Test

The study of the function of spatial hearing (ototopics) is aimed at developing methods for topical diagnosis of the levels of damage to the sound analyzer.

The study is carried out in a soundproof room equipped with a special acoustic installation consisting of a sound generator and loudspeakers located in front of the subject in the vertical and horizontal planes.

The task of the subject is to determine the localization of the sound source. The results are evaluated by the percentage of correct answers. With sensorineural hearing loss, the accuracy of determining the localization of the sound source is reduced on the side of the worse hearing ear. The vertical localization of sound in these patients varies depending on the hearing loss to high tones. With otosclerosis, the ability to localize sound in the vertical plane is completely excluded, regardless of the frequency spectrum of the testing sound, while horizontal localization changes only depending on the asymmetry of the auditory function. With Meniere's disease, there is a constant violation of ototopics in all planes.

Methods of objective research of hearing

Basically, these methods are used in relation to young children, persons undergoing an examination for the presence of auditory function, and patients with a defective psyche. The methods are based on the assessment of auditory reflexes and auditory evoked potentials.

auditory reflexes

They are based on reflex connections of the organ of hearing with the sensorimotor sphere.

Preyer's auropalpebral reflex(N. Preyer, 1882) - involuntary blinking that occurs with a sharp sudden sound. In 1905, V. M. Bekhterev suggested using this reflex in order to detect simulation of deafness. Various modifications of this reflex were used in N. P. Simanovsky's clinic. Currently, this reflex is used to exclude deafness in infants.

Aurolaryngeal reflex(J. Mick, 1917). The essence of this reflex lies in the fact that under the influence of an unexpected sharp sound, a reflex closing of the vocal folds occurs, followed by their dilution and a deep breath. This reflex in the expert sample is very reliable, since it refers to unconditional reactions that do not depend on the will of the subject.

auropupillary reflex(G. Holmgren, 1876) consists in reflex expansion, and then in the narrowing of the pupils under the influence of a sudden strong sound.

Freschels reflex(Froeschels). It consists in the fact that with a sharp sound there is an involuntary deviation of the gaze towards the source of the sound.

Tsemakh's reflex(Cemach). With a sudden loud sound, there is a tilt of the head and torso (removal reaction) in the direction opposite to that from which a sharp strong sound was heard.

Sound motor reflexes of muscles tympanic cavity . These unconditioned reflexes, which occur in response to suprathreshold sound stimulation, are widely used in modern audiology and audiology.

auditory evoked potentials

The method is based on the phenomenon of generation in the neurons of the auditory zones of the cerebral cortex of bioelectric evoked potentials, arising from the sounding of the receptor cells of the spiral organ of the cochlea, and the registration of these potentials with the help of their summation and computer processing; hence the other name of the method - computer audiometry. In audiology, auditory evoked potentials are used for topical diagnosis of central disorders of the sound analyzer (Fig. 6).

Rice. 6. Schematic representation of the average auditory evoked biopotentials

Methods for the study of the auditory tube

The study of the auditory tube is one of the main methods for diagnosing diseases of both this organ and the middle ear and their differential diagnosis.

Scoping Methods

At otoscopy dysfunctions of the auditory tube are manifested by: a) retraction of the relaxed and stretched parts of the tympanic membrane; b) an increase in the depth of the cone of the tympanic membrane, due to which the short process of the malleus protrudes outwards (symptom of the “index finger”), the light reflex is sharply shortened or completely absent.

At epipharyngoscopy(posterior rhinoscopy) assess the condition of the nasopharyngeal mouths of the auditory tubes (hyperemia, senechia, damage, etc.), the condition of the tubal tonsils and adenoid tissue, choanae, vomer, retrospective of the nasal passages.

Pneumootoscopy

The technique is carried out using a Siegle funnel (1864), equipped with a rubber canister to influence the eardrum with an air jet (Fig. 7).

Rice. 7. Siegle funnel with pneumatic attachment

With normal ventilation function of the auditory tube, an impulse increase in pressure in the external auditory canal causes vibrations of the tympanic membrane. In violation of the ventilation function of the auditory tube or in the adhesive process, the mobility of the membrane is absent.

Salpingoscopy

To examine the nasopharyngeal mouth of the auditory tube, modern optical endoscopes are used.

Currently, to examine the auditory tube, the thinnest fiberscopes with controlled optics at the distal end are used, which can penetrate through the auditory tube into the tympanic cavity to conduct tubotympanic microfibroendoscopy.

Blowing out the auditory tube. This method is used for both diagnostic and therapeutic purposes. For it, a special rubber balloon is used, connected by means of a rubber tube to the nasal olive, which is inserted into the nostril and tightly clamped together with the other nostril. The subject takes a sip of water, during which the nasopharyngeal cavity is blocked by the soft palate, and the pharyngeal opening of the auditory tube opens. At this moment, the balloon is squeezed, air pressure rises in the nasal cavity and nasopharynx, which, during the normal functioning of the auditory tube, enters the middle ear. Instead of a sip of water, you can pronounce sounds, during the articulation of which the nasopharynx is blocked by a soft palate, for example, “also-also”, “cuckoo”, “steamboat”, etc. When air enters the tympanic cavity in the external auditory canal, you can hear a kind of noise. When listening to this noise, apply Lutze otoscope, which is a rubber tube, at the ends of which there are two ear olives. One of them is inserted into the external auditory canal of the examiner, the other - into the external auditory canal of the subject. Listening is carried out during a sip with a pinched nose ( toynbee test).

A more effective way to determine the patency of the auditory tube is Valsalva test, which consists in an attempt to exhale with a tightly clamped nose and lips. With this test, in the case of patency of the auditory tube, the subject has a feeling of fullness in the ears, and the examiner listens with the help of an otoscope a characteristic blowing or popping sound. Below is a list of the most famous samples.

The principles of assessing the patency of the auditory tube by degrees have survived to this day. A. A. Pukhalsky (1939) proposed to classify the state of the ventilation function of the auditory tubes into four degrees:

• I degree - the noise is heard with a simple sip;
• II degree - noise is heard during the Toynbee test;
• III degree- murmur is heard during the Valsalva maneuver;
• IV degree - the noise is not heard in any of the listed samples. Complete obstruction is assessed by the absence of noise during the Politzer test with a sip of water. If it is impossible to determine the patency of the auditory tube by the above methods, they resort to its catheterization.

Eustachian tube catheterization

The following instruments are required for catheterization of the auditory tube (Fig. 8): Politzer balloon (7) for blowing the auditory tube; Lutze otoscope (2) for listening to ear noise that occurs when air passes through the auditory tube, and an ear catheter (Hartmann cannula) for direct blowing of the auditory tube by catheterization.

Rice. 8. A set of instruments for catheterization of the auditory tube: 1 - rubber balloon; 2 - otoscope - a rubber tube for listening to noise; 3 - catheter for direct probing of the auditory tube

Eustachian tube catheterization technique

The catheter is inserted along the common nasal passage with the beak down until it comes into contact with back wall nasopharynx, turn it 90 ° towards the opposite ear and pull it up to contact with the vomer. Then the catheter is turned with its beak down by 180° towards the studied auditory tube so that the beak faces the side wall of the nasopharynx. After that, the beak is turned upwards by another 30-40 °, so that the ring located at the catheter funnel is directed towards the outer corner of the orbit. The final stage is to search for the pharyngeal opening of the auditory tube, during which the ridges of this opening (posterior and anterior) can be determined. Getting into the hole is characterized by a feeling of "capture" of the end of the catheter. Next, the conical end of the balloon is inserted into the catheter socket and air is pumped into it with light movements. With the patency of the auditory tube, a blowing noise is heard, and during otoscopy after blowing, the injection of the vessels of the tympanic membrane is detected.

Ear manometry is based on the registration of an increase in pressure in the external auditory canal, which occurs when pressure increases in the nasopharynx and the presence of patency of the auditory tube.

Currently, the study of the function of the auditory tube is carried out using phonobarometry And electrotubometry.

Phonobarometry allows you to indirectly set the amount of air pressure in the tympanic cavity and control the state of the ventilation function of the auditory tube.

Impedance Audiometry(English) impedance, from lat. impedio I resist, resist. Under acoustic impedance understand the complex resistance experienced by sound waves passing through certain acoustic systems and leading these systems into forced oscillations. In audiology, the study of acoustic impedancemetry is aimed at determining the qualitative and quantitative characteristics of the sound-conducting system of the middle ear.

Modern impedance measurement includes the measurement of the absolute value of the input impedance, i.e., the acoustic impedance of a sound-conducting system; registration of changes in the input impedance under the influence of contraction of the muscles of the tympanic cavity and a number of other indicators.

Acoustic reflexometry allows you to evaluate the reflex activity of the muscles of the tympanic cavity and diagnose auditory dysfunction at the level of the first neuron. Main diagnostic criteria are: a) threshold value stimulating sound in dB; b) latency period acoustic reflex, reflecting the functional state of the first neuron, from the beginning of the sound stimulus to the reflex contraction of the ipsi- or contralateral stapedial muscle; in) nature of change acoustic reflex depending on the magnitude of the suprathreshold sound stimulus. These criteria are identified when measuring the parameters of the acoustic impedance of the sound-conducting system.

Otorhinolaryngology. IN AND. Babiak, M.I. Govorun, Ya.A. Nakatis, A.N. Pashchinin

Audiometry refers to medical procedure measuring the level of human hearing, which is characterized by the completeness of the biofunctional susceptibility of the hearing analyzer in humans and the occurrence of disturbances in anatomical structure. The term "audiometry" was formed by the merging of two words - the Latin audio (to hear) and the Greek metreo (to measure).

To check your hearing and conduct audiometry, you must consult a (ENT doctor),.

Principle and features of the procedure

A person with healthy hearing perfectly perceives both colloquial speech and speech that others utter in a whisper. But sometimes such sensitivity can decrease and a person stops hearing quieter speech or a whisper. This is due to injuries, birth defects, professional activities that affect hearing, diseases. To assess the susceptibility of various tones of sounds in medicine, hearing audiometry is used.

The technique of hearing audiometry helps to recognize the threshold of perception of sounds in each individual patient at a certain point in time. The procedure is very simple and does not require sophisticated equipment. All the equipment used in the course of audiometry are tuning forks and audiometers.

The main criterion for the norm of hearing is the ability to recognize a person's whisper, which is pronounced at a distance of six meters from the ear being examined. When used during the test, an audiometer can identify both the level of hearing sensitivity and the location of the lesion in the body that interferes with the normal functioning of the hearing aid.

Audiometry is very simple. In that auricle, which is currently being examined, an audio signal is given, which is necessary for the doctor to determine the state of frequency and strength. If the patient perceives the signal (that is, hears), he presses the button, if he does not recognize it, then he does not press it. This process perfectly characterizes the threshold of hearing.

When performing computer audiometry, the patient should fall asleep. The day before, special sensors are fixed on his head, which perceive changes in strength. brain waves. The computer, using special electrodes, helps to independently control all the patient's brain reactions and build a diagram based on them.

The indications for a hearing test are:

• chronic or acute deafness;
• inflammatory process of the middle ear - otitis media;
• the process of selecting a hearing aid for the patient;
• testing the effectiveness of the therapy.

Audiometry has no contraindications. It can be carried out at any time, while the patient does not experience any discomfort or pain. In time, the process takes about half an hour.

There are a lot of varieties of modern audiometry, it can be:

• tonal;
• threshold;
• computer;
• speech;
• objective;
• game;
• suprathreshold;
• screening.

Carrying out tone audiometry

To more accurately measure the patient's threshold of sound perception, the specialist conducts hearing tests in the range from 125 to 8000 hertz. With tone audiometry, it becomes possible to determine the minimum and maximum sound levels that are comfortable for the person being examined.

An audiometer is used during this procedure, where, with the help of headphones that are connected to the device, a signal of a certain tone is fed into the auricle. If the patient heard the signal, he presses a special button, and if this does not happen, then the tone of the signal increases. This happens until the moment when the signal becomes audible and the patient presses the button. This indicator is the lower limit of the patient's hearing level. The maximum level is determined exactly according to the same scheme.

Pure tone audiometry can be used for any age of patients, however, a playful form is more suitable for toddlers. As a result of the study, the specialist receives an accurate and complete picture of the patient's auditory parameters.

Features of the threshold technique

Threshold audiometry is performed using an audiometer. The minimum frequency of the device is 125 hertz, and then it will threshold increase with a run-up of 67.5 hertz to the maximum frequency provided for by a particular audiometer model. A similar procedure is carried out in a soundproof room. If such conditions are not created, then the specialist must take into account the impact of external noise on the test results. To smooth out this imperfection of the procedure, in-the-ear headphones are often used, which can increase the accuracy of studies to identify the level of hearing.

The advantages of in-the-ear headphones are the ability to reduce third-party noise, reduce the need for masking sounds due to inter-aural relaxation, and eliminate the collapse of the external auditory canals. These benefits are of particular importance when working with newborns. The accuracy and regularity of repeating the results suggests that this technique can be considered very reliable. At the same time, analyzing the schedule of individual air permeability, the specialist has the opportunity to draw conclusions about the level of functioning of the middle ear and its condition.

With complete deafness, this technique does not allow you to immediately identify the site of the lesion; to determine it, it is necessary to conduct additional suprathreshold tests. Among such methods, the Fowler or Langenbeck tests, various noise methods are especially popular. Similar types of analyzes will clarify for specialists exactly where the damage is located - in the ear labyrinth, in the cells of the vestibular or auditory nerve.

Use of computer and speech audiometry

Computer audiometry is the most accurate method for determining hearing acuity. Computer equipment provides the patient with complete freedom of action and movement, he can relax and not focus on hearing certain sounds in a timely manner. The equipment itself is able to determine all the limit values, it acts absolutely painlessly and safely, so this method is widely used to make an accurate diagnosis even in newborns.

With speech audiometry, on the contrary, all actions are carried out exclusively by the patient and the doctor without the use of any technical means and devices. This is the most early method hearing threshold. The result of this procedure can be largely determined not by hearing, but by the intellect and vocabulary of a sick person. Such a technique can give different results when the audiometrist pronounces individual words or arranges them into sentences. Offers are always better perceived by patients and are easier to distinguish.

Modern medicine practically does not use this technique. It is used today exclusively in cases where specialists need to test a patient to choose the right hearing aid for him.

Features of objective audiometry

The objective technique is used in newborns and in the forensic industry. It is based on the analytical features of conditioned and unconditioned reflexes of the human body, which should respond to audio stimuli of different frequencies. The reactions of the body can be recorded with this method for reasons beyond the control of the will of the organism being examined.

Among the unconditioned reflexes that are considered with objective audiometry, one can distinguish dilated eye pupils or a cochlear-pupil reaction, closing eyelids with sudden sounds or an auropalpebral reflex, inhibition of sucking in a newborn with various sounds, contractile ability of circular eye muscle, galvanic skin changes, reactions of the vascular system.

Modern objective audiometry is subdivided into acoustic impedancemetry, which includes the process of recording the acoustic reflex, and tympanometry, electrocochleography, and electroencephaloaudiometry. At the same time, tympanometry helps to assess the mobility of the eardrums, the chain of the bone part of the patient's hearing aid, and with the help of an acoustic reflex, a signal passing from the intra-ear muscles is recorded as a response to the impact on the patient's eardrum. Electrocochleography allows you to electrically stimulate the auditory nerve, and electroencephaloaudiometry demonstrates to the doctor the potential of the cerebral auditory zone.

Game technique

Play audiometry is mostly used when working with children's category of patients. Children cannot reflexively press lifeless buttons for a long time, therefore the principle of using game moments is used in the methodology. For example, when a sound is heard and a button is pressed little patient will be able to see a new bright picture or some kind of game object, which will stimulate him to follow the commands of the audiologist.

When playing audiometry, a tone audiometer is often used, which was once proposed by specialist Jan Lesak. The audiometer is a toy house with people, animals, vehicles. A small patient is given a remote control in the form of a fungus, with which he can perform certain actions when right conditions. For example, in order to free a little man from captivity, a small patient must wait until he is asked about it and press the appropriate button on the fungus. So the audiometrist understands that his signal was heard by the child. A similar technique is proposed by the doctor Kosachev, there are also methods for determining hearing in young patients, tested by other specialists in the industry.

The importance of audiometry in children is expressed in the fact that with a poor level of hearing, babies have a delay in speech development.

Method of suprathreshold audiometry

The suprathreshold method for testing hearing acuity was proposed and tested by Luscher. Thanks to this method, specialists now have the opportunity to evaluate the differential threshold of sound power - the index of small increases in intensity. This study most often performed if there is a risk of an increase in the volume of lymph in the cavity inner ear(Ménière's disease), auditory neuroma ( benign neoplasm, the source of which is the auditory nerve). The technique of suprathreshold audiometry is used for unilateral hearing loss, but it can also be used for bilateral anomalies of the hearing aid. In this case, a certain sound signal will be delivered to each ear, which must correspond to the threshold norm of a particular hearing aid. For example, if on one ear the threshold value should be equal to 5 decibels, then on the second, the permissible value may be 40. In this case, the signal that enters the sore ear is gradually increased by 10 decibels, and the boundary sound value supplied on a healthy ear, they are brought into such correspondence that it seems to the patient that a signal of the same intensity is given in both ears. This is how the tone is equalized with a gradual gradation to one threshold equal to 10 decibels.

Application of screening audiometry

A medical audiometer today can be represented by three types of devices - outpatient, screening or clinical. The simplest device is a screening audiometer, which provides the specialist with a much wider field of possibilities during the procedure than the same outpatient device.

Tone diagnostics of audibility is carried out in this case according to the indicators of sound conductivity of air masses. The screening audiometer is a mobile device, its functionality will allow the specialist to individually select the frequencies and tonality of the sounds produced. It is possible to test the patient in both manual and automatic modes.

During testing, an otoscopic instrument connected in parallel will help evaluate the levels of audibility and sound comfort for the patient. With the help of a connected microphone, the doctor has the opportunity to contact the patient, and with the help of a printer, there is a chance to receive an audiogram in printed form.

Cabinet and results of the procedure

For the results of audiometry to be objective, the procedure should be carried out in a well-isolated room, where the parallel influence of external noise on the process is minimized. Also, the space where the examination takes place must be protected from electric and magnetic waves.

The room should be free, especially with the speech method, and the distance from the patient to the doctor should be at least 6 meters. The best place for this diagnosis is a specialized acoustic chamber, which is adapted for audiometry.

After the procedure, the specialist receives several special graphics on two-axis planes. On the horizontal axis there are divisions expressed in hertz, and they characterize the frequencies of tones. The vertical axis shows the sound intensity in decibels. The sound perception of the right ear is shown on the red curve, which has circles, and the left ear on the blue curve with crosses.

Tedeeva Madina Elkanovna

Speciality: therapist, radiologist.

General experience: 20 years .

Place of work: LLC “SL Medical Group”, Maikop.

Education:1990-1996, North Ossetian State Medical Academy.

Training:

1. In 2016 in the Russian medical academy postgraduate education, she underwent advanced training in the additional professional program "Therapy" and was admitted to the implementation of medical or pharmaceutical activities in the specialty of therapy.

2. In 2017 by decision examination committee at a private institution of additional professional education "Institute for Advanced Training of Medical Personnel" is admitted to the implementation of medical or pharmaceutical activities in the specialty radiology.

Work experience: therapist - 18 years, radiologist - 2 years.