[The current tendencies and prospects of the neural response telemetry in the rehabilitation of the patients after cochlear implantation].

The objective of the present study was to estimate the potential of the modern technique for telemetry of the neural response during rehabilitation of the patients following cochlear implantation. The methods for the purpose included comparison of the results of intra- and postoperative registration on neural response telemetry (NRT) and evaluation of the influence of perimodiolar localization of electrodes of cochlear implants on the threshold level of stimulation and propagation of excitation inside the cochlea. The results of the study confirm the possibility of using the registration of the electrically evoked auditory nerve potential for fitting the speech processor of the cochlear implant. In addition, it was shown that the application of the perimodiolar electrode significantly narrows the intracochlear excitation distribution profile which enhances the rehabilitative effectiveness of cochlear implantation.

[The effectiveness of rehabilitation following bilateral cochlear implantation].

The Russian Federation similar to many other countries witnesses the continuous rise in the number of patients undergoing bilateral cochlear implantation. The objective of the present study was to estimate the effectiveness of rehabilitation following bilateral cochlear implantation. A total of 28 patients admitted to the Russian Research and Practical Centre of Audiology and Hearing Rehabilitation between 2011 and 2012 were available for the examination with the use of tonal threshold audiometry. Twenty one patient underwent sequential cochlear implantation, simultaneous implantation was effected in the remaining 7 ones. The patients were tested by a speech therapist. The tonal threshold audiometry in the free sound field showed that the auditory thresholds corresponded to grade I hearing impairment. Free-field sound perception threshold in the bilaterally implanted patients with two active speech processors was significantly better than in those having one speech processor. All the patients exhibited binaural summation effect. Surdopedagogical testing revealed positive dynamics of the speech development. The positive dynamics was especially well apparent pronounced in the patients operated simultaneously or when the period between two implantations did not exceed 1 year. A reduction of the duration of the period between two surgical interventions resulted in the decreased difference between sound perception in two ears, improvement of sound localization, and acceleration of speech development. All the patients showed good speech recognition in the complex acoustic environment and the ability to locate sounds.

[The experience of the work of a regional cochlear implantation center].

The objective of the present study was to determine the main lines of the development of a regional cochlear implantation centre and to estimate the effectiveness of rehabilitation of the children treated with the use of cochlear implantation. Analysis of the results of the work of the branch of the Russian Research and Practical Centre of Audiology and Hearing Rehabilitation based at Voronezh Regional Children's Clinical Hospital No 1 provided materials for the establishment of the principle directions of activities of the regional cochlear implantation centre where a total of 161 children have been kept under observation during the last years. Fifty six of the 138 children at the age varying from 1 to 12 years were given the surgical treatment. The patients were followed up within two and more years after connection of the speech processor. The study group was comprised only of the pre-lingually deaf children. It is concluded that the performance of most cochlear implantation procedures based at local centres allows to reduce the cost of rehabilitation and makes the high-tech medical aid more readily available to the patients; moreover, the practical introduction of remote speech processor programming software into the work of regional cochlear implantation centres enhances the effectiveness of the rehabilitative measures based at local medical facilities.

[Novel possibilities for the rehabilitation of patients presenting with congenital external and middle ear malformations].

The objective of the present study was to estimate the advantages of cochlear Baha BIA 400 abutments in the intraoperative and early postoperative periods. A total of 10 implantations of the systems with the use of hydroxyapatite bone cement were performed in 9 patients of different age. Stability of the implants and intensity of skin reactions were evaluated. The data obtained indicate that the use of cochlear Baha BIA 400 abutments significantly simplifies and shortens the surgical stage of rehabilitation producing a good cosmetic result. The use of the Osstell instrument made it possible to estimate stability of the implants intraoperatively and evaluate the effectiveness of osteointegration during the follow-up period. Analysis of the results of the study provided a basis on which to improve the quality and shorten duration of the rehabilitative treatment of the patients presenting with congenital external and middle ear malformations. Moreover, the data obtained can be used to develop practical recommendations for the further work in this area.

[The audiological phenotype and the prevalence of GJB2-related sensorineural loss of hearing in the infants suffering acoustic disturbances].

The objective of the present work was to study specific features of the audiological phenotype and the prevalence of GJB2-related sensorineural hearing loss (SNHL) in the infants suffering acoustic disturbances. The study included 264 children with bilateral non-syndromic sensorineural loss of hearing diagnosed during the first year of life by means of detailed audiological examination that included tympanometry, registration of short-latency auditory action potentials (SLAAP), delayed evoked otoacoustic emission (DEOAE), distortion product-frequency otoacoustic emission (DPFOAE), and auditory brain-stem response (ABR). In addition, stationary acoustically evoked responses (SAER) were recorded in 38 children presenting with hearing impairment associated with GJB2-related sensorineural loss of hearing. The follow-up dynamic study involved 113 children subjected to repeated audiological examination. The study revealed the genotype with pathological mutations in 182 (69.0%) children including 171 (64.8%) ones with biallelic mutations and 11 (4.2%) with a single mutation (heterozygous genotype). Eighty two (31.0%) children had genotype without mutations. A total of 21 different mutations and 30 different genotypes were identified. Analysis of the family histories of the children showed that neither the absence of relatives suffering from hearing impairment nor the presence of risk factors of acquired hearing impairment excludes the possibility of GJB2-related sensorineural loss of hearing in the infants. Otoacoustic emission fails to be registered in the majority of the children with the altered genotype (87%) during the stay in the maternity house. Mutations in the GJB2 gene are most frequently diagnosed in the patients with the moderate, moderately severe, and severe loss of hearing. At the same time, almost half of the infants presenting with the mild loss of hearing were found to exhibit changes in the GJB2 gene. The thresholds of registration of short-latency auditory action potentials remain stable in 90.0% of the children presenting with GJB2-related sensorineural loss of hearing which makes it possible to choose the strategy of their rehabilitative treatment (the use of hearing aids or cochlear implantation) during the very first months of life and predict the favourable outcome of cochlear implantation and hearing aid measures. The results of the present work illustrate the importance and practical significance of genetic studies (GJB2 gene tresting) of the infants suffering sensorineural loss of hearing and other acoustic disturbances for the elucidation of etiology of these conditions, prognosis of the disease, and the choice of the strategy for its treatment.

[Johanson-Blizzard syndrome: audiological features and results of cochlear implantation].

Johanson-Blizzard syndrome is a rare congenital autosomal recessive disease characterized by the association of congenital deficiency of the exocrine pancreatic function and multiple malformations. One of the most common manifestations of this pathology is sensorineural hearing loss of different severity and anomalous development of the inner ear. The case of cochlear implantation in the patient presenting with bilateral sensorineural deafness, congenital malformation of the inner ear, and stenosis of the internal auditory canal is reported.

[Cochlear implantation in immunocompromised patients].

This paper reports a clinical case that gives evidence of the possibility of cochlear implantation after liver transplantation. Patient K. aged 3 years 10 months was admitted to the Russian Research and Practical Centre of Audiology and Hearing Rehabilitation with the diagnosis of type IB glycogenosis after maternal liver transplantation associated with chronic neutropenia, chronic cutaneous and mucosal infection, partial symptomatic partial epilepsy, retarded psycho-motor development, and complaints of the absence of auditory response. The audiological examination provided materials for the diagnosis of grade IV bilateral sensorineural hearing loss tending toward deafness. Cochlear implantation recommended to the patient was performed on February 20, 2013 using the HiRes 90 K implant with the HiFocus Helix electrode (Advanced Bionics, USA). The surgical intervention and the postoperative period passed without complications. The speech processor was activated one month after surgery. The results of surdopedagogical testing gave evidence of successful rehabilitation promising the further improvement. It is concluded that immunosuppressive therapy is not an absolute contraindication for cochlear implantation, but this procedure requires detailed examination and thorough preparation for the forthcoming surgery.