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Introduction: In the past years, some groups established methods to use promontory stimulation and subjective responses as a tool for preoperative stimulation of the cochlea before cochlear implant (CI) surgery by a temporary transtympanic needle placed on the middle ear. Our research group tested CI candidates when the presence of the auditory nerve could not be confirmed by other pre-operative tests and analyzed objective results of electrical auditory brainstem response recorded with trans-tympanic promontory stimulation in local anesthesia (LA-TT-EABR) with a “golfclub” electrode placed on the round window niche (Polterauer et al. 2018). However, EABR recording suffers from an electrical artifact from the stimulation and focuses on the excitability of the solely auditory nerve. We hypothesize that late evoked potential response (EALR) can be used for the assessment of the auditory pathway up to the cortical area with less electrical artifact interference. Methods: The trans-tympanic electrically evoked auditory late response in local anesthesia (LA-TT-EALR) was added to our protocol right after the LA-TT-EABR in a unique recording session. In this study, we investigated the feasibility of LA-TT-EALR using MED-EL hardware and software. These two pre-operative trans-tympanic measurements, LATT- EABR and LA-TT-EALR, were compared. Results: In a total n=18 tested subjects, it could be possible to record LA-TT-EABR in 10 and LA-TT-EALR in 13. In contrast to the fact that acoustically evoked auditory late responses are often hard to detect, and an electrical artifact heavily affects LA-TT-EABR, we did not experience these problems on LA-TT-EALR recordings. The matching between two measurements was present in 67% of the cases. Conclusion: LA-TT-EALR may be a complement to the existing state-of-the-art LA-TT-EABR for pre-operative assessment before cochlear implantation offering information about auditory pathways in the auditory brainstem and cortex with a small increase of recording time. The equivalency of these two methods is encouraging.

Współczesne systemy implantów ślimakowych poprzez bezpośrednią stymulację zakończeń nerwu słuchowego zapewniają uzyskanie prawidłowych reakcji akustycznych. Jednak warunkiem poprawnego funkcjonowania implantu jest dokładne zbadanie stymulowanej elektrycznie drogi słuchowej, a następnie odpowiednie – optymalne dla danego pacjenta – ustawienie parametrów stymulacji. W tym celu stosowane są zarówno metody psychoakustyczne, jak i obiektywne. Do niedawna za pomocą metod obiektywnych u użytkowników implantów ślimakowych możliwe było przeprowadzenie pomiarów funkcjonowania zakończeń nerwu słuchowego oraz kolejnych, wyższych pięter drogi słuchowej. Obecnie dzięki rejestracji wywołanych akustycznie potencjałów z nerwu słuchowego możemy badać także aktywność zachowanych komórek słuchowych oraz lepiej poznać mechanizmy funkcjonujące w ślimaku.

When listening with a cochlear implant through one ear and acoustically through the other, binaural benefits and spatial hearing abilities are generally poorer than in other bilaterally stimulated configurations. With the working hypothesis that binaural neurons require interaurally matched inputs, we review causes for mismatch, their perceptual consequences, and experimental methods for mismatch measurements. The focus is on the three primary interaural dimensions of latency, frequency, and level. Often, the mismatch is not constant, but rather highly stimulus-dependent. We report on mismatch compensation strategies, taking into consideration the specific needs of the respective patient groups. Practical challenges typically faced by audiologists in the proposed fitting procedure are discussed. While improvement in certain areas (e.g., speaker localization) is definitely achievable, a more comprehensive mismatch compensation is a very ambitious endeavor. Even in the hypothetical ideal fitting case, performance is not expected to exceed that of a good bilateral cochlear implant user.

Prior to cochlear implantation, audiological tests are performed to determine candidacy in subjects with a hearing loss. This is usually done by measuring the acoustic auditory brainstem response (ABR). Unfortunately, for some subjects, a reproducible ABR recording cannot be obtained, even at high acoustic levels. Having a healthy stimulating auditory nerve is required for cochlear implantation in order to benefit from the electrical pulses that are generated by the implant and to improve speech comprehension. In some subjects, this prerequisite cannot be measured using routine audiological tests. In this study, the feasibility of recording electrically evoked auditory brainstem responses (eABR) using a stimulating transtympanic electrode, placed on the round window niche, together with MED-EL clinical system is investigated. The results show that it is possible to record reproducible eABR measurements using PromBERA. The response was also confirmed with intraoperative eABR measurements that were stimulated using the implanted CI electrode array. Similarities between the intraoperative measurements and the preoperative recorded waveforms were observed. In summary, the integrity and excitability of the auditory nerve can be objectively measured using the PromBERA in subjects where standard clinical testing procedures are unable to provide the information required.

OBJECTIVES: The intracochlear electrocochleography (ECoG) could be recorded directly from the cochlear implant (CI) electrode in CI recipients with residual hearing. The primary objective of this study is to identify the most sensitive frequency to record cochlear microphonics (CM) in CI users with a wide degree of hearing abilities and deep electrode insertion. The secondary objective is to identify the optimum location within the cochlea to record intracochlear potentials. MATERIALS AND METHODS: CMs were recorded from the CI electrodes in eight females and eight males implanted with CIs Pulsar, Concerto, or Sonata, Med-El Corp. RESULTS: Among the tone pips of various frequencies, 1k or 500 Hz were the most sensitive for CI users. The most sensitive place in the cochlea to record the CM potentials depended on the tone frequency used. The deeper into the cochlea the mean maximum CM peak-to-peak amplitude was measured, the lower the stimulating tone frequency was. CONCLUSION: The most optimal recording parameters identified for intracochlear CM recording can be useful for intraoperative and postoperative monitoring of cochlear health in CI users with residual hearing.

7th IEEE Asia-Pacific Conference on Applied Electromagnetics, APACE 2016 -- 11 December 2016 through 13 December 2016 -- 127632 ‘Second Consensus Meeting on Management of Complex Inner Ear Malformations: Long Term Results of ABI in Children and Decision Making Between CI and ABI’ took place on 5–6 April 2013 in Kyrenia, Northern Cyprus with the participation of 20 centers from 11 countries. These centers presented their auditory brainstem implantation (ABI) experience in children and infants and also provided the selection criteria and cochlear implant (CI) results in patients with an abnormal cochlea and nerve. In addition, Cochlear and Med El companies provided presentations regarding solutions to problems during revision surgery and future projections of device technology. According to the results from different centers, it was evident that an ABI is capable of providing hearing sensation in prelingually deafened children with complex inner ear malformations and diseases. It is possible to obtain a pure tone average with an ABI between 30 and 60 dB HL in most of these patients. It has been observed that the majority of children obtain Categories of Auditory Performance (CAP) scores around 5, but occasionally certain ABI users obtained scores of up to CAP 8-II, NEAP-Nottingham Early Assessment Package. The Ear Foundation 2009). CAP scores tend to increase with earlier implantation, i.e. under 2 years of age. However, after 3 years of use, it usually reaches a plateau. Children with additional disorders cannot reach CAP scores of children without disorders. However, they obtain an improvement of cognitive functions but duration of ABI use and increasing chronological age also play a role in this improvement.

[Objective]: To use an intracochlear test electrode to assess the integrity and the functionality of the auditory nerve in cochlear implant (CI) recipients and to compare electrical auditory brainstem responses (eABR) via the test electrode with the eABR responses with the CI., [Setting]: Otolaryngology department, tertiary referral hospital., [Patients]: Ten subjects (age at implantation 55 yr, range, 19–72) were subsequently implanted with a MED-EL CONCERTO CI on the side without any useful residual hearing., [Interventions]: Following identification of the round window (RW), the test electrode was inserted in the cochlea previous to cochlear implantation., [Main Outcome Measures]: To assess the quality of an eABR waveform, scoring criteria from Walton et al. (2008) were chosen. The waveforms in each session were classified by detecting waves III and V by the algorithm and visual assessment of the waveform. Speech performance was evaluated with monosyllables, disyllables, and sentence recognition tests., [Results]: It was possible to evoke electrical stimulation responses along with both the test electrode and the CI in all subjects. No significant differences in latencies or amplitudes after stimulation were found between the test electrode and the CI. All subjects obtained useful hearing with their CI and use their implants daily., [Conclusions]: The intracochlear test electrode may be suitable to test the integrity of the auditory nerve by recording eABR signals. This allows for further research on the status of the auditory nerve after tumor removal and correlation with auditory performance.

Recently, cochlear implant (CI) eligibility criteria have broadened to include individuals with partial deafness, a condition in which, prior to implantation, a significant amount of low-frequency hearing remains. Cochlear implantation aimed for hearing preservation in partial deafness has been recognized as a new method of partial deafness treatment. However, it is not only hearing preservation that has a great influence on the performance of such users; it is also the fitting of the audio processor consisting of acoustic and electric part. In this paper the authors review results of recent studies that underline the importance of correct fitting of the audio processor in order to achieve good benefits in Electric-Acoustic Stimulation (EAS).

A favela no Rio de Janeiro constitui um fenômeno que, no espaço das últimas décadas, evoluiu, criando vários mecanismos sociais ausentes em outras partes da cidade. O artigo foca a análise das relações de poder na favela a partir dos trabalhos de Hannah Arendt e Erich Fromm, apontando na direção de soluções sistêmicas típicas de sistemas totalistas, o que traz consigo várias consequências para a formação humana do indivíduo. Le bidonville carioca constitue un phénomène qu’a augmenté dans les dernières décennies, en créant plusiers mécanismes sociaux qui n’existent pas dans les autres espaces de la ville. L’article souligne l’analyse des rapports de pouvoir dans le bidonville carioca à partir des travaux de Hannah Arendt et Erich Fromm, en indiquant des solutions systémiques propres aux systèmes « totalistes », ce qui apporte plusiers effets sur la formation humaine de l’individu. The slum of Rio de Janeiro is a phenomenon which, during the time of decades of evolution, has created several social mechanisms absent in other parts of the city. The article is focused on analyzing the relations of power in the slum, from the theoretical concepts of Hannah Arendt and Erich Fromm. It shows the evolution of the relations of power in the slum into direction of systematic solutions characteristic for totalistic systems, which brings with itself various consequences for human individual development. La favela del Rio de Janeiro constituyó un fenómeno, cual en espacio de las décadas del desarrollo ha creado varios mecanismos sociales ausentes en las otras partes de la cuidad. El artículo concentra-se en una reseña de las relaciones del poder en la favela, desde los conceptos teoréticos de Hannah Arendt y Erich Fromm. El artículo apunta a la evolución de las relaciones del poder en la favela en la dirección de las soluciones sistemáticas particulares para las sistemas totalistas, lo que lleva consigo varias consecuencias para desarrollo individual del sujeto.

Objective The aim of this study was to assess the benefit of having preserved acoustic hearing in the implanted ear for speech recognition in complex listening environments. Design The present study included a within-subjects, repeated-measures design including 21 English-speaking and 17 Polish-speaking cochlear implant (CI) recipients with preserved acoustic hearing in the implanted ear. The patients were implanted with electrodes that varied in insertion depth from 10 to 31 mm. Mean preoperative low-frequency thresholds (average of 125, 250, and 500 Hz) in the implanted ear were 39.3 and 23.4 dB HL for the English- and Polish-speaking participants, respectively. In one condition, speech perception was assessed in an eight-loudspeaker environment in which the speech signals were presented from one loudspeaker and restaurant noise was presented from all loudspeakers. In another condition, the signals were presented in a simulation of a reverberant environment with a reverberation time of 0.6 sec. The response measures included speech reception thresholds (SRTs) and percent correct sentence understanding for two test conditions: CI plus low-frequency hearing in the contralateral ear (bimodal condition) and CI plus low-frequency hearing in both ears (best-aided condition). A subset of six English-speaking listeners were also assessed on measures of interaural time difference thresholds for a 250-Hz signal. Results Small, but significant, improvements in performance (1.7-2.1 dB and 6-10 percentage points) were found for the best-aided condition versus the bimodal condition. Postoperative thresholds in the implanted ear were correlated with the degree of electric and acoustic stimulation (EAS) benefit for speech recognition in diffuse noise. There was no reliable relationship among measures of audiometric threshold in the implanted ear nor elevation in threshold after surgery and improvement in speech understanding in reverberation. There was a significant correlation between interaural time difference threshold at 250 Hz and EAS-related benefit for the adaptive speech reception threshold. Conclusions The findings of this study suggest that (1) preserved low-frequency hearing improves speech understanding for CI recipients, (2) testing in complex listening environments, in which binaural timing cues differ for signal and noise, may best demonstrate the value of having two ears with low-frequency acoustic hearing, and (3) preservation of binaural timing cues, although poorer than observed for individuals with normal hearing, is possible after unilateral cochlear implantation with hearing preservation and is associated with EAS benefit. The results of this study demonstrate significant communicative benefit for hearing preservation in the implanted ear and provide support for the expansion of CI criteria to include individuals with low-frequency thresholds in even the normal to near-normal range.

This review covers the molecular mechanisms involved in hair cell and hearing losses which can result from trauma generated during the process of cochlear implantation and the contributions of both the intrinsic and extrinsic cell death signaling pathways in producing these trauma/inflammation induced losses. Application of soft surgical techniques to conserve hearing and protect auditory sensory cells during the process of cochlear implantation surgery and insertion of the electrode array during the process of cochlear implantation are reviewed and discussed. The role of drug therapy and mode of drug delivery for the conservation of a cochlear implant patient's residual hearing is presented and discussed.

This review covers the general roles of members of the cysteine protease family of caspases in the process of apoptosis (programmed cell death) looking at their participation in both the "extrinsic" cell death receptor and the "intrinsic" mitochondrial cell death pathways. It defines the difference between initiator and effector caspases and shows the progression of caspase activations that ends up in the apoptotic cell death and elimination of a damaged cell. The review then presents what is currently know about the participation of caspases in the programmed cell death of inner ear sensory cells during the process of normal development and maturation of the inner ear and their importance in this process as illustrated by the results of caspase-3 gene knockout experiments. The participation of specific caspases and the sequence of their activation in the elimination (apoptosis) of damaged sensory cells from adult inner ears after an injury that generates oxidative stress are reviewed. Both the possibility and the potential efficacy of caspase inhibition with a broad-spectrum pancaspase inhibitor as an interventional therapy to treat and rescue oxidative stress-damaged inner ear sensory cells from apoptosis are presented and discussed.

This study investigates the role of hearing in vowel productions of postlingually deafened cochlear implant (CI) users. Based on the hypothesis that competing demands of intelligibility and economy of effort influence vowel production, we predicted that speakers of a language with a more crowded vowel space, such as American English, would show an increase in average vowel spacing (AVS the average inter‐vowel distance in the F1‐F2 plane) with the provision of hearing from a CI; whereas speakers of a language with fewer vowels, such as Spanish, would not. Results of a preliminary on–off study supported the hypothesis: with hearing from a CI, 7 English‐speaking CI users all increased AVS; however, among 7 Spanish speakers, some increased AVS and some reduced it. The current study is exploring these findings further with new groups of CI users and normal‐hearing speakers of English and Spanish and an elaborated paradigm that includes different speaking rates and comparisons between pre‐implant and post‐impla...

This study investigates the effects of speaking condition and auditory feedback on vowel production by postlingually deafened adults. Thirteen cochlear implant users produced repetitions of nine American English vowels prior to implantation, and at one month and one year after implantation. There were three speaking conditions (clear, normal, and fast), and two feedback conditions after implantation (implant processor turned on and off). Ten normal-hearing controls were also recorded once. Vowel contrasts in the formant space (expressed in mels) were larger in the clear than in the fast condition, both for controls and for implant users at all three time samples. Implant users also produced differences in duration between clear and fast conditions that were in the range of those obtained from the controls. In agreement with prior work, the implant users had contrast values lower than did the controls. The implant users' contrasts were larger with hearing on than off and improved from one month to one year postimplant. Because the controls and implant users responded similarly to a change in speaking condition, it is inferred that auditory feedback, although demonstrably important for maintaining normative values of vowel contrasts, is not needed to maintain the distinctiveness of those contrasts in different speaking conditions.