[Electrically evoked ABR through cochlear implant in children with auditory neuropathy spectrum disorder]. / Registratsiya elektricheski vyzvannykh korotkolatentnykh slukhovykh potentsialov u detei s zabolevaniem spektra auditornykh neiropatii.

OBJECTIVE: To estimate the applicability of electrically evoked auditory brainstem response (eABR) registration for the estimation of neural integrity after cochlear implantation (CI) in children with auditory neuropathy spectrum disorder (ANSD) and to compare the eABR data with patient's hearing performance. MATERIAL AND METHODS: 4 children, Nucleus (Cochlear) CI users, with ANSD were enrolled in the study. Hearing performance in these children ranged from successful to unsatisfied. eABR were recorded via Eclipse EP25 (Interacoustics). Electrical bipolar stimulation was achieved with Custom Sound EP software (Cochlear). RESULTS: EABR were registered with the use of different stimulation parameters (pulse width, stimulated electrodes) in 3 patients with satisfactory results of rehabilitation. eABR thresholds corresponded to maximum comfortable levels of patients stimulation MAP. eABR were absent in the patient with poor hearing performance. CONCLUSIONS: EABR measurements in children with ANSD demonstrated restoration of neuronal conduction in the auditory pathway up to the brainstem after cochlear implantation in 3 patients. eABR results were well correlated with hearing performance. Thereby, the study of eABR applicability for clinical practice will be expanded.

[Evaluation of the cochlear implantation users rehabilitation results using psychoacoustic methods]. / Otsenka rezul'tatov reabilitatsii pol'zovatelei kokhlearnykh implantatov s primeneniem psikhoakusticheskikh metodov issledovaniya.

Currently, the number of patients with bilateral sensorineural deafness treated with cochlear implantation (CI) is increasing in the Russian Federation. In this regard, methods of assessing the auditory rehabilitation of this category of patients become more relevant. OBJECTIVE: To investigate the correlation of the speech intelligibility in quiet with frequency resolving power (FRP) of hearing using a ripple-spectrum phase reversion test (RSPRT) in CI users. MATERIAL AND METHODS: The study includes 30 CI users, three of them after bilateral CI, aged from 13 to 63 years with CI usage experience from 1 year to 16 years. 19 patients used CI systems manufactured by Cochlear Ltd. (Australia), 11 patients used CI systems manufactured by Advanced Bionics (Switzerland). All subjects underwent a number of studies including pure tone audiometry (TPA), speech audiometry in quiet using a multi-syllable speech material on a two-channel clinical audiometer AC-40 (Interacoustics A/S, Denmark); PC with recorded phonetic material from which the signal was reproduced, acoustic speaker SP90 (Interacoustics A/S, Denmark), for FRP estimation - RSPRT test in a free sound field, which was installed on the PC and also reproduced through SP 90 speakers (Interacoustics A/S, Denmark) were used. RESULTS: According to TPA results in a free sound field, the sound perception thresholds in all subjects corresponded to the mild degree sensorineural hearing loss. The sound perception threshold in the free sound field in the range from 500 Hz to 4 kHz was within the range of 25-30 dB nHL. The percentage of speech intelligibility in quiet in the free sound field ranged from 5 to 100%. During the FRP study of patients using RSPRT test, the following results were obtained: the average value of RSPRT test results at the frequency of 1 kHz was 1.94 RPO; for 2 kHz - 2.3 RPO; for 4 kHz - 2.2. The significant correlation between the speech intelligibility in quiet and frequency resolution of hearing was obtained at 1 and 4 kHz. The highest correlation coefficient was detected at 1 kHz - r=0.57 (p=0.0005), while at 4 kHz it was lower - r=0.46 (p=0.009), and at 2 kHz - at the boundary of the significance: r=0.34 (p=0.051). CONCLUSIONS: As a result of the study, it was found that there is a correlation between speech intelligibility in quiet and FRP of hearing, which makes it possible to recommend the use of RSPRT in assessing the auditory rehabilitation of patients after CI.

[Postoperative dynamics of electrode impedance changes in children with cochlear implants]. / Posleoperatsionnaya dinamika soprotivleniya elektrodov u detei s kokhlearnymi implantami.

To determine the electrode impedance dynamics changes in the postoperative period after cochlear implantation as well as the time of their stabilization. MATERIAL AND METHODS: 75 patients with a bilateral sensorineural deafness aged from 1 to 4 years (average age - 1.5 years) were included in the study. 50 patients were implanted with Nucleus cochlear implants (Cochlear - Australia) and other 25 patients - with Advanced Bionics implants (Switzerland). RESULTS: The impedance dynamics analysis in two groups of patients implanted with «Cochlear¼ and «Advanced Bionics¼ cochlear implants demonstrated that statistically significant decrease in impedance (p<0.05) was observed after the beginning of electrical stimulation and the reduction of postoperative inflammatory process in the inner ear. The stabilization of the impedance levels in both groups of patients was obtained in 3-6 months after the switch-on of speech processor.

[Threshold dynamics of the auditory nerve electrically evoked compound action potential in implanted children]. / Dinamika porogov elektricheski vyzvannogo potentsiala deistviya slukhovogo nerva u implantirovannykh detei.

OBJECTIVE: To study the dynamics of thresholds of the electrically evoked compound action potential of the auditory nerve (ECAP) during neural responce telemetry (NRT) intraoperatively, at the time of activation of the cochlear implantation system (CI) and after 3 and 6 months. MATERIAL AND METHODS: The study included 50 children aged 1 year to 4 years with bilateral sensorineural deafness, operated on by Nucleus CI512 Profile + CP900 CI systems («Cochlear¼, Australia). In all patients, the electrode array was fully inserted. The dynamics and thresholds of ECAP were recorded and assessed in dynamics: when performing NRT intraoperatively, when the CI system was activated, and after 3 and 6 months. To assess the thresholds, the 1st, 6th, 11th, 16th and 22nd electrodes of the multichannel electrode array were selected. RESULTS: The average threshold values and the NRT threshold profile determined intraoperatively and during measurements at different times after the activation of the CI system were significantly different (p<0.001), while the average postoperative results were characterized by relative stability. It was shown that the thresholds determined on the electrodes located in the middle of the electrode lattice are more stable than the thresholds determined on the apical and basal electrodes. In most patients, the NRT threshold values determined at the time of the activation of the CI system and after 3 and 6 months were significantly lower than the thresholds determined intraoperatively. The data obtained allow us to conclude that NRT is a stable and accurate technique that allows you to objectify the process of setting up an individual card for the stimulation of the speech processor at the rehabilitation stage after cochlear implantation.

[Evoked potentials in the rehabilitation of the patients after cochlear implantation]. / Vyzvannye potentsialy v reabilitatsii patsientov posle kokhlearnoi implantatsii.

The objective methods for the hearing examination of the patients after cochlear implantation provide an important tool for the speech processor fitting. The aim of the present study was to evaluate the possibilities and the informative value of the electrically evoked compound action potential (ECAP) and electrically evoked auditory brainstem response (EABR) combined recording technique. For this reason, the comparison of the ECAP and EABR thresholds with comfortable levels of stimulation, obtained on the basis of subjective response and psychophysical testing of the patients with good results after cochlear implantation was performed. 19 patients with the CI experience from 1 to 5 years were included in our study. The combined registration of ECAP and EABR can be used to evaluate the functional capacity of the central auditory pathways and for the fitting of the complicated patients, especially those in whom the registration proved impossible with the use of other objective techniques. The ECAP and EABR threshold values were well correlated with the individual stimulation map profiles in the patients with the CI experience of less than two years (p<0.05). The results obtained in the present study allow us to conclude that combined registration of ECAP and EABR could be used for the determination of stimulation comfort level parameters and individual stimulation map profiles, especially in combination with the minimum amount of psychoacoustic information received from the patient.

[The effectiveness of the speech therapist and audiologist collaboration during speech processor fitting]. / Éffektivnost' sovmestnoi raboty surdopedagoga i surdologa v khode nastroek rechevogo protsessora.

The aim of the study was to present the first clinical experience of clinical trials of new methodology of the CI speech processor fitting with the new software Nucleus Fitting Software - NFS. At all 4 fittings sessions there were 15 children. During the fitting sessions 2 techniques were used - with the new NFS software and classical technique were used. The efficiency and need of collaboration of the speech therapist and the audiologist in the CI fitting sessions is proved. Results of inspection have shown that in 76.6% parents have established emotional cooperation with the children. Most of children have begun to seize the spontaneous speech in natural communication (60% - words, 23.3% - simple phrases). The results received by us allow to recommend the offered technique of the facilitated speech processor fitting technique for widespread introduction in clinical practice.

Phenotype in a patient with p.D50N mutation in GJB2 gene resemble both KID and Clouston syndromes.

Keratitis-ichthyosis-deafness (KID) syndrome (OMIM 148210) is a rare ectodermal dysplasia syndrome characterized by vascularizing keratitis, congenital profound sensorineural hearing loss, and progressive erythrokeratoderma. We have found a 148G-A transition in the GJB2 gene, resulting in an asp50-to-asn (D50N) substitution in a girl with congenital deafness. This finding allowed us to diagnose а KID syndrome. But clinical features were uncommon because of a mild skin manifestation, lack of keratitis and unusual appearance resembling Clouston syndrome. Molecular genetic tests showed that it was de novo mutation because parents have normal genotype. Several autosomal dominant mutations in the GJB2 gene (сonnexin 26) now established to underlie many of the affected cases, with the majority of patients harboring the p.D50N mutation. Skin disease-associated mutation of connexin proteins can cause functional disturbances in gap junction intercellular conductance. It is likely that multiple disease mechanisms are involved across the wide spectrum of hereditary diseases relating to connexin proteins. The clinical data may provide additional insights into the dysregulation mechanisms of mutations result in the disease.

[Reoperations after cochlear implantation]. / Reoperatsii pri kokhlearnoi implantatsii.

The objective of the present study: the improvement of the quality and effectiveness of the surgical stage of cochlear implantation on the basis of the comprehensive analysis of performed reoperations. PATIENTS: 84 patients of the 2413 ones who had undergone cochlear implantation were re-examined by revision surgery within various periods after the first intervention. MAIN RESULTS: In certain patients, the correction of the intracochlear electrode array position was performed and in 72 cases the replacement of the implant was done. The most frequent cause of the replacement of the implant was the failure of the device. In the case of the extrusion and inflammation, the two-stage surgical treatment was applied. The exposure of the different parts of the cochlear implant with the duration up to 2 weeks was considered as a complication which could be adequately corrected. The surgical treatment of such patients was carried out in a single stage. The reparation processes at the place of the first intervention were strongly expressed, especially in children. Standardization of the cochlear implantation surgical stage based on the determination of its optimum volume in our Center led to a decrease in the number of reoperations and made the learning process easier to master for young otosurgeons. CONCLUSION: It is can be concluded that the reoperation after primary cochlear implantation is a highly effective technique and, taking into account the listed features, doesn't present difficulties for the qualified otosurgeon.

[The results of cochlear implantation in the patient with hereditary and non-hereditary hearing loss]. / Rezul'taty kokhlearnoi implantatsii u patsientov s nasledstvennymi i nenasledstvennymi formami tugoukhosti.

The objective of the present study was to evaluate the effectiveness of rehabilitation of the patients after cochlear implantation in the early and late periods after operation taking into consideration the etiology of congenital deafness. The comprehensive clinico-audiological examination performed during the period from 2010 to 2015 involved 246 children who had undergone cochlear implantation (CI). All children were operated at the National Research Center for Audiology and Hearing Rehabilitation in the period from 2003 to 2013. 83 (56%) patients were aged 1 to 3 years at the time of surgery. Their age varied from 3 to 18 years when they underwent the clinico-audiological examination. Thus, the study is based on the experience with cochlear implantation varying from 3 to 12 years. The genetic analysis revealed mutations in the GJB2 gene in 49% of the children, in agreement with the data of earlier studies. 85% of all the children with GJB2 deafness surgically treated at the age under 4 years attend ordinary institutions of learning. Within 24 months after the onset of the observations the majority of the children with hereditary deafness (63%) were referred to the groups with good and excellent results of the rehabilitation and only 6 (12%) patients presented with unsatisfactory results. It was shown that the acquired causes of the loss of hearing including severe prenatal pathology have a negative influence on the long-term outcomes of rehabilitation. The results of the genetic analysis for the elucidation of the cause of impaired hearing can be employed as a prognostic criteria not only for the prediction but also for the guarantee of the success of cochlear implantation provided the rehabilitative process was initiated in a proper time.

[The impact of implantable technologies on the quality of life in the patients with hearing loss]. / Vliyanie implantatsionnykh tekhnologii na kachestvo zhizni patsientov s narusheniem slukha.

The improvement of the effectiveness of the rehabilitation of the patients with hearing disorders is a priority task for an audiologist. One part of the present work was to assess satisfaction of the patients treated with the use of the hearing aids, drug therapy, and the surgical operations. The aim of the study was to evaluate the influence of the implantation of the Baha bone conduction system on the quality of life of the treated patients. The Russian-language versions of the Glasgow Benefit Inventory and Glasgow Children Benefit inventory questionnaires were used. The survey was conducted among the patients with bilateral moderate and moderate-to-severe conductive hearing loss due to congenital malformation of the external and middle ears or chronic suppurative otitis media followed by canal-down operation. A total of 47 patients took part in the present multicenter study. The results demonstrate the high effectiveness of rehabilitation with the use of the implantable bone conduction system. The beneficial effect of the treatment was especially well apparent in the children. The results are comparable with the data of the similarly designed investigations reported in the literature. Peculiarities of the data obtained in the present study and statistical characteristics made it possible to validate the Russian-language versions of the Glasgow Benefit Inventory and Glasgow Children Benefit inventory questionnaires.

[Application of the mathematical model for prognosis in the rehabilitation of children after cochlear implantation]. / Ispol'zovanie matematicheskoi modeli dlya opredeleniya prognoza reabilitatsii u detei posle kokhlearnoi implantatsii.

Despite the variety of etiological factors, cochlear implantation (CI) remains the only effective method for the rehabilitation of the patients presenting with total deafness. The aim of this study was the enhancement of the efficiency of selection of the candidates for CI, the improvement of the quality of rehabilitation of the patients with cochlear implants, and the determination of the prognostic criteria for clinical trials. PATIENTS AND METHODS: (CI). The decision-making support system (DMSS) based on the artificial neural networks (ANNs) has been created to enhance the efficiency of rehabilitation of the patients with cochlear implants and increase the effectiveness of the selection of candidates for cochlear implantation. The results of the children's rehabilitation after CI have been analyzed by using a mathematical model of artificial neural networks (Kohonen layer). The basis for the assessment of ANNs was formed by the results of the observations of audioverbal perception in 110 patients aged from 6 months to 17 years. The initial data were the average values obtained with the use of the Russian-language version of the Nottingham children's implant profile's test T1 - T3. The testing was performed before CI and 3, 6, 12, 18, and 24 months after it. MAIN RESULTS: The work yielded the four-cluster data structure. It made it possible to estimate the effectiveness of the clinical trials in selected classes depending on the etiology of the disease, the age of the patients, and their experience with the application of hearing aids. The reliable estimation of the dynamics of auditory perception at the stage of rehabilitation and prognosis of the outcomes of CI made it possible to take additional preventive and therapeutic measures in the combination with complementary psychological and educational procedures.

[The Russian-language version of the matrix test (RUMatrix) in free field in patients after cochlear implantation in the long term]. / Russkoyazychnaya versiya matriksnogo frazovogo testa RUMatrix v svobodnom zvukovom pole u patsientov posle kokhlearnoi implantatsii.

The deterioration of speech intelligibility in the patients using cochlear implantation (CI) systems is especially well apparent in the noisy environment. It explains why phrasal speech tests, such as a Matrix sentence test, have become increasingly more popular in the speech audiometry during rehabilitation after CI. The Matrix test allows to estimate speech perception by the patients in a real life situation. The objective of this study was to assess the effectiveness of audiological rehabilitation of CI patients using the Russian-language version of the matrix test (RUMatrix) in free field in the noisy environment. 33 patients aged from 5 to 40 years with a more than 3 year experience of using cochlear implants inserted at the National Research Center for Audiology and Hearing Rehabilitation were included in our study. Five of these patients were implanted bilaterally. The results of our study showed a statistically significant improvement of speech intelligibility in the noisy environment after the speech processor adjustment; dynamics of the signal-to-noise ratio changes was -1.7 dB (p<0.001). CONCLUSION: The RUMatrix test is a highly efficient method for the estimation of speech intelligibility in the patients undergoing clinical investigations in the noisy environment. The high degree of comparability of the RUMatrix test with the Matrix tests in other languages makes possible its application in international multicenter studies.

[The new technologies for the intraoperative registration of the electrically evoked compound action potentials of the acoustical nerve by means of the neural response telemetry method].

The present article reports the results of a clinical study of the new wireless device CR120 designed for the intraoperative registration of electrode resistance and the electrically evoked compound action potential (EAP) of the acoustical nerve by means of neural response telemetry. The study has demonstrated the high effectiveness of the application of the new wireless device in clinical practice. It was shown that the registration of electrically evoked compound action potential with the help of the CR120 Intraoperative Remote Assistant took 22% less time than by the conventional method (p<0.001). Moreover, the trial revealed the strong correlation between the threshold EAP values recorded with the use of the new device and by the classical method.