[Morphological changes in the epithelium of the auditory tube with prolonged respiratory support in children of the first year of life]. / Morfologicheskie izmeneniya epiteliya slukhovoi truby pri dlitel'noi respiratornoi podderzhke u detei pervogo goda zhizni.

OBJECTIVE: To analyze the condition of the epithelium of the cartilaginous part of the auditory tube in premature and full-term infants with prolonged respiratory support using noninvasive assisted ventilation (continuous positive airway pressure - CPAP) and artificial lung ventilation (ventilator). MATERIAL AND METHODS: All the obtained material is distributed relative to the gestation period into the main and control groups. The main group (25 children) is represented by premature and full-term live-born children who were on respiratory support for a period of several hours to 2 months, the average gestation period of which was 30 weeks and 40 weeks, respectively. The control group (8 children) is represented by stillborn newborns with an average gestation period of 28 weeks. The study was conducted posthumously. RESULTS: Prolonged use of respiratory support in premature and full-term children, regardless of the type (CPAP or ventilator), leads to a violation of the row of cilia of the ciliated epithelium, various inflammatory processes, as well as to the expansion of the ducts of the mucous glands of the epithelium of the auditory tube, which affects its drainage system. CONCLUSION: Prolonged respiratory support causes destructive changes in the epithelium of the auditory tube, which make it difficult to evacuate the mucous discharge from the tympanic cavity. This negatively affects the ventilation function of the auditory tube and in the future may lead to the development of chronic exudative otitis media.

[Objective parameters of auditory function in premature infants in the first year of life after taking ototoxic antibiotics]. / Ob"ektivnye pokazateli slukhovoi funktsii u nedonoshennykh detei pervogo goda zhizni posle priema ototoksicheskikh antibiotikov.

OBJECTIVE: To compare the condition of auditory function during the first year of life according to the registration of distortion product otoacoustic emission (DPOAE) and short-latency evoked potentials (SLEP) in premature infants who received ototoxic antibiotics to those ones, who did not. MATERIAL AND METHODS: Auditory function was examined in 145 premature infants. Auditory assessment was carried out by registration of DPOAEs, SLEPs and tympanometry. Statistical processing was performed using the program Statgraphics Centurion XV. RESULTS: In this study, according to DPOAE, the average response values of the cochlea in premature infants who had a history of ototoxic therapy, undergo final changes after children reach the age of 6 months. The study of latent periods and threshold values of the V peak of SLEP showed a delay in the maturation process of the perceiving and conducting auditory structures during the first year of life in children who received ototoxic antibiotics in the first month of life. CONCLUSION: We evaluated the timing of the completion of response changes in children of the control group using the DPOAE and SLEP registration data. In children of the study group, we evaluated the effect of the administered ototoxic antibiotics. Timing of audiological control of the hearing organ condition are demonstrated for premature children after ototoxicosis, required methods of its examination are established.

Otoprotective Effect of Cortexin, Cogitum, and Elkar Administered Simultaneously with Netromycin in the Experiment.

We studied possible otoprotective effect of drugs widely used for the correction of perinatal hypoxic brain damage in premature infants. The experiments were carried out on immature rabbits with an immature hearing organ. The auditory function was assessed by DPOAE and ABR methods in intact animals and rabbits treated with therapeutic doses of netromycin alone or in combination with the drugs that normalize metabolic processes in the brain (Cortexin, Cogitum, Elkar, vitamin B2, ATP, and cocarboxylase). It was found that the administered drugs produced an otoprotective effect and reduced the severity, but did not eliminate the ototoxic effect.

[Screening audiological control in children of different ages after taking ototoxic medications]. / Skriningovyi audiologicheskii kontrol' detei raznogo vozrasta posle priema ototoksicheskikh preparatov.

AIM: To compare auditory function during screening of children of different age groups who received ototoxic therapy. PATIENTS AND METHODS: Auditory function was studied in various categories of children receiving ototoxic drugs. Hearing was assessed by the registration of distortion product otoacoustic emission (DPOAE), short-latency evoked potentials (SLEP), tympanometry. Statistical processing was performed using the C program Statgraphics Centurion XV. RESULTS: In this study, screening of auditory function in children suffering from cystic fibrosis and receiving ototoxic treatment revealed pathologic conditions of the middle ear according to tympanometry in 15.4% of cases, impaired auditory function in 28.2% of cases according to DPOAE. Early ototoxicosis presented as a decrease in the amplitude of the response at a frequency of 4 kHz, and a change in the structure of the DP-gram in the form of a shift to the low-frequency area. Examination of the auditory function of premature infants receiving potentially ototoxic drugs in the early neonatal period demonstrated that the administration of ototoxic drugs does not affect the maturation of outer hair cells. CONCLUSION: Audiological control, such as tympanometry and registration of evoked otoacoustic remission should be included in the outpatient observation of children with a history of ototoxic drugs.

Effects of Cocarboxylase in Amikacin-Induced Ototoxicity in Immature Animals.

Possible otoprotective properties of cocarboxylase were studied on the model of amikacin-induced ototoxicity in immature rabbits. Auditory function was evaluated by the short-latency auditory brainstem response (ABR) and distortion product otoacoustic emission (DPOAE) tests. Administration of cocarboxylase after modeling of amikacin-induced ototoxicity resulted in a decrease in the ABR peak I threshold and prevented damage to the outer hair cells.

[The role of gastroesophageal reflux disease in the development of chronic exudative otitis media in the children during the first year of life]. / Rol' gastroézofageal'noi refliuksnoi bolezni v formirovanii khronicheskogo ékssudativnogo srednego otita u detei pervogo goda zhizni.

The objective of the present study was the determination of the incidence of gastroesophageal reflux disease and the evaluation of its possible influence on the development and duration of chronic exudative otitis media in the children during the first year of life. A total of 141 infants at the age of 3 months presenting with exudative otitis media refractory to the conservative treatment throughout the first 1-1.5 months of life were available for the examination. The effectiveness of the anti-reflux therapy was estimated based on the middle ear condition (the presence or absence of exudate) within 3 and 6 months after the initiation of the treatment. The signs of aspiration of gastric chimus and gastroesophageal reflux disease were documented in 92% of the cases. The anti-reflux treatment during 3 months resulted in the disappearance of the manifestations of exudative otitis media in 43% of the patients. The further prolongation of such therapy up to 6 months allowed to normalize the state of the middle ear in 69% of the children although the remaining 40% failed to respond. It is concluded that the treatment of the children presenting with exudative otitis media during first year of life should be performed taking into consideration the possible involvement of gastroesophageal reflux disease in pathogenesis of this pathological condition.

[The hearing function in the premature children following their treatment with the use of ototoxic antibiotics]. / Slukhovaia funktsiia nedonoshennykh detei posle lecheniia ototoksicheskimi antibiotikami.

The objective of the present study was the evaluation of the state of the auditory function in the premature children during the first year of life who underwent the neonatal treatment with various ototoxic antibiotics. A total of 232 newborn infants were available for the examination by the methods designed for recording distortion product optoacoustic emission (DPOAE) and short-latency auditory evoked potentials (SAEPs). The 'Statgraphics Centurion XV' program was used for the statistical treatment of the data obtained in the study. The results of recording DPOAE and SAEPs in 232 prematurely born children of different gestational age were used to evaluate their auditory function under conditions of treatment with various ototoxic antibiotics during the early neonatal period. It was shown that such treatment is likely to have an impact on the hearing function of premature children throughout the entire first year of life. Such influence can manifest itself as the enhanced threshold of the appearance of SAEPs peak V and the selective distortion of evoked responses recorded with the help of the DPOAE technique at a frequency of 4.6 kHz. It is concluded that all prematurely born children should be under observation of an otorhinolaryngologist-surdologist throughout the entire first year of life and, if appropriate, undergo the rehabilitative treatment at the earliest possible time. Moreover, the children with this condition must remain under the thorough follow-up care during at least 3 years including the yearly audiological evaluation and the comparative analysis of the results of previous observations for the timely identification of possible disturbances in the hearing function.

[The relationship between the parameters of evoked otoacoustical emission and tympanometry in the children born with the extremely low body weight]. / Vzaimosviaz' parametrov vyzvannoi otoakusticheskoi émissii i timpanometrii u detei, rozhdennykh s ékstremal'no nizkoi massoi tela.

The objective of the present study was to elucidate correlation between the parameters of evoked otoacoustical emission at the distorsion product otoacoustic emissionen frequency (DPOAE) and the results of tympoanometry performed at the probe tone frequencies of 226 Hz and 1 kHz in the children born with the extremely low body weight. The results of the study give evidence of the moderate correlation dependence between the strength of the cochlear acoustic response at DPOAE and the cohlear response amplitude at the frequencies of 2 kHz and 6 kHz from TTP (r=0.3; p=0.000) obtained at the tympanometry probe tone frequency of 1 kHz. The correlation between the magnitude of the acoustic response of the cochlea, the amplitude of this response at the frequencies of 2 kHz and 6 kHz, the width of the tympanograms, and their static compliance obtained in the studies at the tympanometry probe tone frequency of 1,000 Hz (r=0.3-0.5; p=0.001) was documented in the infants at the age of 6 months and 1 year.

[The anatomical features of the middle ear exerting the influence on the formation of exudative otitis media in the breast-fed infants of different gestational age]. / Anatomicheskie osobennosti srednego ukha, vliiaiushchie na formirovanie ékssudativnogo srednego otita u grudnykh detei razlichnogo gestatsionnogo vozrasta.

The objective of the present study was to elucidate the anatomical features of the structure of the middle ear and eustachian tube in the breast-fed infants of different gestational age that may be responsible for the formation of exudates (fluids). We have examined 150 temporal bones obtained from the children's cadavers that were allocated to three groups as follows: 50 temporal bones obtained at weeks 26-30 weeks of gestation (group 1), 44 bones 31-36 weeks of gestation (group 2), and 37-40 weeks of gestation (full-term babies, group 3),The analysis of the data obtained on an individual bases revealed either increase or decreases in the selected characteristics of the eustachian tube in comparison with the respective average values as well as the well apparent predominance of a single change or a combination of alteration of several parameters in one case in 26-30 weeks and 31-36 weeks groups. No significant changes were found in group 1. It is concluded that the presence of a single change or a combination of two or three abnormal changes in the parameters of the bone structures of the eustachian tube can affect the development of the secretory process in the middle ear especially in the children born after 36 weeks of pregnancy.

Effect of Successive Administration of Vancomycin and Amikacin on Auditory Function of Immature Animals.

Effect of successive administration vancomycin and amikacin in therapeutic doses on immature auditory organ was compared to single administration of the same drugs in chronic experiments on immature rabbits by recording of short-latency auditory brainstem response (ABR) and distortion product otoacoustic emission (DPOAE). Drug administration always increased significantly the ABR peak I threshold. Ototoxic antibiotics did not change DPOAE, but selectively affected activity of outer hair cells. No enhancement of the ototoxic effects was observed after successive administration of the two antibiotics.

[The results of primary audiological examination of the children presenting with intrauterine growth retardation and normotrophics born after multifetal and singleton pregnancies].

The objective of the present work was the comparative study of the state of the acoustic analayzer in the full-term and premature infants born after multifetal (MP) or singleton (SP) pregnancies with the body weight at birth corresponding to the gestational age (normotrophics) and presenting with intrauterine growth retardation (IUGR). The method of distortion product otoacoustic emissions (DPOAEs) was employed in the study. It has demonstrated that the normotrophic babies born at the gestational age over 34 weeks after singleton pregnancy pass the DPOAEstest significantly more frequently than normotrophics of the same gestational age born after multifetal pregnancy. Moreover, the unilateral impairment of hearing in the full-term infants born after multifetal pregnancy occurs more frequently than in those born after singleton pregnancy.

Auditory Function in Immature Animals after Two Consecutive Courses of Ototoxic Antibiotics.

In chronic experiments on immature rabbits receiving therapeutic courses of vancomycin, gentamicin, and consecutive administration of vancomicin and gentamicin by the scheme used in neonatology, hearing function was evaluated by the methods of auditory evoked potentials (auditory brainstem response, ABR) and distortion product otoacoustic emission (DPOAE). Comparison with the control group revealed ototoxic effects of all studied antibiotics that manifested in increased sound tolerance and more rapid shortening of latencies in 30-100 dB range. Higher thresholds were found only after gentamicin administration. Vancomycin administration significantly reduced the responses at 4 kHz. Subsequent gentamicin course did not potentiate this effect.

[Tympanometry in premature babies during the first year of life].

The objective of the present work was to study the tympanograms of the premature infants during the first year of their life and to determine the optimal time for performing high-frequency and low-frequency tympanometry in the babies of different gestational age. It was shown that the middle ear as an apparatus of the sound-transmitting system becomes to function stably by the 6th month of life although the mechanisms for regulation of stabilization develop only in the end of the first year. For this reason, tympanometry in the children of the gestational age 29 - 32 , 33 - 37 и 38 - 40 weeks should be performed using two frequencies of the probing tone (226 Hz and 1 kHz) up to the 6 months of life inclusive and from 28 weeks to 1 year.Key words: premature baby, tympanometry, acoustic function.

[The evaluation of the hearing function in the premature infants with intrauterine growth retardation during the third and sixth months of life by recording auditory steady-state response].

The objective of the present work was to study the function of the retrocochlear auditory pathway in the premature infants with intrauterine growth retardation (IGR) in comparison to that of the normotrophics of a similar gestational age during the third and sixth months of life by recording auditory steady-state responses (ASSR). The audiological examination by the method of auditory steady-state response (ASSR) involved 127 children at the 3d month of life and in 97 children at the 6th month of life. It was shown that the ASSR thresholds at certain frequencies during the 3d and 6th months of life of the children born after the 32d week of pregnancy were significantly higher than in the children born after 32 weeks gestation. The comparison of the two objective audiological methods, viz. distortion-product otoacoustic emission (DPOAE) and ASSR, indicates that both should be used to evaluate the hearing function during the third and sixth months of life to compensate for the discrepancy between the results obtained by either technique.

Effect of gentamicin on the auditory analyzer in sexually immature animals.

Auditory function of immature rabbits was evaluated using two electrophysiological methods, brainstem auditory evoked response (BAER) and distortion product otoacoustic emission (DPOAE), in chronic experiments following administration of therapeutic doses of gentamicin. Impairment of auditory function manifested in increased thresholds and decreased amplitude of the 1st BAER peak was established. DPOAE parameters were not significantly changed. It was suggested that gentamicin decreased activity of spiral ganglion neurocytes in animals with immature auditory analyzer.

[The hearing function in the one-year old children with intrauterine growth retardation evaluated by two objective audiological methods].

The objective of the present study was to collect objective information about the hearing function in the prematurely born infants suffering intrauterine growth retardation (IUGR). The audiological examination of 77 patients at the age of 12 months was performed using two different methods making use of distortion product otoacoustic emission (DPOAE) and evoked auditory steady state responses (ASSRs). Hearing disorders were diagnosed in the children presenting with grade II and III IUGR born prior to the 34th week of pregnancy. The results of the study indicate that the children with grade II and III intrauterine growth retardation born earlier than the 34th week of pregnancy are at risk of developing hearing impairment and should be under dynamic audiological observation with the use of two objective methods, namely DPOAE and ASSR.

[Tympanometry in the premature infants of different gestational age during the primary audiological examination].

The objective of the present work was to study specific approaches of tympanometry in the premature infants of different gestational age. A total of 122 typmanograms (243 ears) were available for the analysis. Peculiarities of recording tympanograms and their characteristics in the premature infants of different gestational age (including static compliance, intratympanic pressure, and tympanogram width) have been demonstrated. The optimal frequency of tympanometry in the premature infants of different gestational age was determined.

[Peculiarities of the development of antrum in the prematurely born infants].

The objective of the present study was to elucidate specific surgical anatomical features of the antrum in the children prematurely born at different gestational age. A total of 70 temporal bones from 35 newborn infants were available for the examination. The study revealed clinical and anatomical peculiarities in the antrum structure of the children prematurely born at different gestation age.

[The study of maturation of the auditory analyzer rabbit according distortion-product otoacoustic emissions].

AIM: In our chronic experiment to register changes of acoustic response of Distortion-Product Otoacoustic Emissions (DPOAE) of intact rabbits in postnatal ontogenesis for the purpose of getting normative data which can be used for studying impact of pathological factors on auditory function and maturation of activity of outer hair cell in ontogenesis. MATERIALS AND METHODS: Study of otoacoustic emissions used mature chinchilla rabbits with a 19 day life of up to 3 months. RESULTS: In the course of ripening were obtained functional activity of outer hair cells of the cochlea. CONCLUSION: normative data obtained allow us to study using a rabbit model, the pathological effects of agents on the maturation of the outer hair cells of the cochlea in the experiment.

[Clinical and anatomical features of the middle ear in the premature infants at different gestational time].

The objective of the present study was to analyse anatomical features of the middle ear in the premature infants of different gestational age. Materials from 100 still-born and live-born babies (200 temporal bones) were available for the investigation. The study has revealed a number of distinctive clinical and morphological peculiarities in the structure of tympanic membranes in both the prematurely born infants depending on the gestational age and in the full-term babies. The fluid from the tympanic cavity was found to contain human beta-chorionic gonadotropin.