[Online training for hearing implant surgery : A new approach to otological training. German version]. / Online-Training für Hörimplantatchirurgie : Ein neuer Ansatz in der otologischen Ausbildung.

OBJECTIVE: Education in microsurgery of the ear includes staged training to allow for mastering of the complex microsurgical procedures, particularly in the context of middle ear reconstruction and cochlear implantation. Traditional surgical training includes temporal bone preparations by cadaver dissection and supervised operating room practice. As these on-site trainings are limited, there is a need to broaden education facilities in an on-line format. Therefore, a first basic on-line training for otosurgery was developed. MATERIALS AND METHODS: The system consists of an artificial temporal bone model together with a set of basic surgical instruments and implant dummies. As an essential part of the training kit, a high-resolution camera set is included that allows for connection to a video streaming platform and enables remote supervision of the trainees' surgical steps by experienced otological surgeons. In addition, a pre-learning platform covering temporal bone anatomy and instrumentation and pre-recorded lectures and instructional videos has been developed to allow trainees to review and reinforce their understanding before hands-on practice. RESULTS: Over the three courses held to date, 28 participants with varying levels of prior surgical experience took part in this otological surgical training program. The immediate feedback of the participants was evaluated by means of a questionnaire. On this basis, the high value of the program became apparent and specific areas could by identified where further refinements could lead to an even more robust training experience. CONCLUSION: The presented program of an otosurgical online training allows for basal education in practical exercises on a remote system. In this way, trainees who have no direct access to on-site instruction facilities in ear surgery now have the chance to start their otosurgical training in an educational setting adapted to modern technologies.

Unifying information theory and machine learning in a model of electrode discrimination in cochlear implants.

Despite the development and success of cochlear implants over several decades, wide inter-subject variability in speech perception is reported. This suggests that cochlear implant user-dependent factors limit speech perception at the individual level. Clinical studies have demonstrated the importance of the number, placement, and insertion depths of electrodes on speech recognition abilities. However, these do not account for all inter-subject variability and to what extent these factors affect speech recognition abilities has not been studied. In this paper, an information theoretic method and machine learning technique are unified in a model to investigate the extent to which key factors limit cochlear implant electrode discrimination. The framework uses a neural network classifier to predict which electrode is stimulated for a given simulated activation pattern of the auditory nerve, and mutual information is then estimated between the actual stimulated electrode and predicted ones. We also investigate how and to what extent the choices of parameters affect the performance of the model. The advantages of this framework include i) electrode discrimination ability is quantified using information theory, ii) it provides a flexible framework that may be used to investigate the key factors that limit the performance of cochlear implant users, and iii) it provides insights for future modeling studies of other types of neural prostheses.

Initial Experience With a Recently Developed Lateral Wall Electrode.

OBJECTIVE: To review our hearing preservation rates and speech recognition outcomes in patients undergoing cochlear implantation with a recently developed lateral wall electrode. STUDY DESIGN: Retrospective cohort study. METHODS: Retrospective case series of all patients, both pediatric and adult, undergoing cochlear implantation with the Advanced Bionics Hifocus™ SlimJ electrode between December 2017 and January 2020. Main outcomes included hearing preservation rates using several definitions, speech recognition testing primarily through Arizona Biosciences (AzBio) and Consonant-Nucleus-Consonant (CNC) testing, intra- and postoperative complications. RESULTS: Sixty-one ears underwent implantation with the new electrode. Hearing preservation rates were 13.0% to 36.0% depending on the definition used. Speech recognition testing showed significant increases from pre- to postoperative condition (Implant-only AzBio: 24.1 to 48.3, P = .004, binaural AzBio: 46.1 to 65.9, P = .002, Implant-only CNC: 9.7 to 35.1, P < .001, binaural CNC: 29.8 to 59.40, P < .001) with last speech recognition testing occurring an average of 8.8 months postoperatively. The elderly population had the worst hearing preservation rates across all definitions. Five explantations were required due to two infections and three device failures. CONCLUSION: Hearing preservation rates varied significantly depending on the definition used, but users experienced a significant improvement in speech recognition testing after implantation. More work is needed in the community to standardize the definition of residual hearing and hearing preservation. LEVEL OF EVIDENCE: 4 Laryngoscope, 131:2782-2788, 2021.

Hearing Preservation After Cochlear Reimplantation Using Electrocochleography: A Case Report.

Studies have shown that hearing preservation is possible in the context of reimplantation, but residual hearing could not be predicted or expected in these cases. We describe a case in which a patient with mild to profound sensorineural hearing loss who underwent cochlear implantation with a lateral wall array and had hearing preserved postoperatively. She developed facial nerve stimulation which was unresponsive to reprogramming. Using electrocochleography to measure intracochlear trauma during the insertion process, the patient underwent reimplantation with a perimodiolar electrode and hearing was preserved postoperatively. This case demonstrates the potential to use electrocochleography for hearing preservation during reimplantation. Laryngoscope, 131:2348-2351, 2021.

Measurements of the local evoked potential from the cochlear nucleus in patients with an auditory brainstem implant and its implication to auditory perception and audio processor programming.

The measurement of the electrically evoked compound action potential (ECAP) in cochlear implant (CI) patients is widely used to provide evidence of a functioning electrode-nerve interface, to confirm proper location of the electrode array and to program the sound processor. In patients with an auditory brainstem implant (ABI), a likewise versatile measurement would be desirable. The ECAP measurement paradigm "Alternating Polarity" was utilized to record responses via the implanted ABI electrode array placed on the cochlear nucleus. Emphasizing on the different location of stimulation and recording, these responses are called local evoked potentials (LEP). LEP measurements were conducted during the clinical routine in 16 ABI patients (12 children and 4 adults), corresponding to 191 electrode contacts. A retrospective analysis of these data revealed, that LEP responses were observed in 64.9% of all measured electrode contacts. LEP responses predicted auditory perception with a sensitivity of 90.5%. False-positive rate was 33.7%. Objective LEP thresholds were highly significantly (p < 0.001) correlated both to behavioral thresholds (Pearson's r = 0.697) and behavioral most comfortable levels (r = 0.840). Therefore, LEP measurements have the potential to support fitting in ABI patients.

Early Outcomes of Simultaneous Translabyrinthine Resection and Cochlear Implantation.

OBJECTIVES/HYPOTHESIS: Hearing rehabilitation after translabyrinthine resection of a vestibular schwannoma (VS) has largely been based on the transfer of acoustic stimulus to the contralateral ear, typically through a contralateral routing of signal hearing aid or bone-anchored hearing aid (BAHA). Cochlear implant, either as a subsequent surgery or simultaneously, has become a more common treatment option; however, there is still relatively limited data available on its success. The purpose of this study is to evaluate the early outcomes of simultaneous cochlear implantation in patients with sporadic VS undergoing translabyrinthine resection. STUDY DESIGN: Prospective, nonrandomized study. METHODS: A prospective study of nonrandomized patients was completed at a tertiary care neurotology center. Audiologic outcomes, primarily based on AzBIO in quiet and background noise, as well as consonant-nucleus-consonant (CNC) testing of the affected ears were utilized. Tinnitus, dizziness, and spatial hearing questionnaries were also completed. Audiologic outcomes and questionnaires were compared between the pre- and postoperative groups. RESULTS: Ten patients were included in the study with 3 month follow-up data. There was statistically significant improvement in AzBO with +10 and +5 signal to noise ratio and in quiet, as well as in CNC testing (P < .05). There was a significant improvement in Tinnitus Handicap Inventory between the two groups. CONCLUSIONS: Simultaneous cochlear implantation is a viable treatment for hearing loss after translabyrinthine approach to VS. These patients have improved hearing in background noise and tinnitus compared to their preoperative state. Further prognostic data are required to determine which patients are the best candidates. LEVEL OF EVIDENCE: 4 Laryngoscope, 131:E2312-E2317, 2021.

Feasibility of TMS in patients with new generation cochlear implants.

OBJECTIVE: The presence of a cochlear implant is being considered an absolute contraindication for experiments and/or treatments. We aimed to verify TMS (Transcranial Magnetic Stimulation) compatibility of a new generation of cochlear implants. METHODS: In a series of experiments, we test if MED-EL cochlear implants -compatible with stable fields of magnetic resonance imaging scanning- are fully resistant even to rapidly varying magnetic fields as those generated by single pulses and low and high-frequency trains of repetitive TMS (rTMS) applied with a figure of eight coil and different magnetic stimulators. RESULTS: With a TMS intensity equal or below 2.2 Tesla (T) the cochlear implant and all its electronic components remain fully functional, even when the combination of frequency, intensity and number of pulses exceeds the currently available safety guidelines. Induced forces on the implant are negligible. With higher magnetic fields (i.e., 3.2 T), one device was corrupted. CONCLUSIONS: Results exclude the risk of electronic damaging, demagnetizing or displacements of the studied cochlear implants when exposed to magnetic fields of up to 2.2 T delivered through a focal coil. SIGNIFICANCE: They open the way to use focal rTMS protocols with the aim of promoting neural plasticity in auditory networks, possibly helping the post-implant recovery of speech perception performance.

Surgical anatomy of basal turn in relation to middle cranial fossa and round window as pertaining to middle fossa cochlear implant technique.

PURPOSE: The purpose of this investigation was to evaluate the relation of the basal turn of cochlea with middle cranial fossa and round window as pertaining to middle cranial fossa cochlear implant technique. METHODS: Fifty-four formalin preserved temporal bones were micro-dissected to expose the basal turn. The point (f) was marked on the basal turn of cochlea where there was minimum distance of basal turn of cochlea from the floor of middle cranial fossa (f1). The f-f1 distance, the angle (∠smf) and distance of point "f" from the round window (s-f) was measured. RESULTS: The mean minimum distance between basal turn of cochlea and floor of middle cranial fossa (f-f1) was 2.0 ± 0.7 mm.The point f was at mean distance (s-f) and angle (∠smf) of 14.7 ± 1.6 mm and 217° ± 13.7° from round window, respectively. CONCLUSIONS: The information may be helpful for designing appropriate electrode array for middle fossa technique especially for deciding the length of electrode array towards round window, as otherwise electrode may extend into vestibule of inner ear. In the cases where bone thickness between superior part of basal turn of cochlea and middle cranial fossa is < 1.5 mm, surgeon should be extra cautious.

Scalar Translocation Comparison Between Lateral Wall and Perimodiolar Cochlear Implant Arrays - A Meta-Analysis.

OBJECTIVES/HYPOTHESIS: Two types of electrode arrays for cochlear implants (CIs) are distinguished: lateral wall and perimodiolar. Scalar translocation of the array can lead to intracochlear trauma by penetrating from the scala tympani into the scala vestibuli or scala media, potentially negatively affecting hearing performance of CI users. This systematic review compares the lateral wall and perimodiolar arrays with respect to scalar translocation. STUDY DESIGN: Systematic review. METHODS: PubMed, Embase, and Cochrane databases were reviewed for studies published within the last 11 years. No other limitations were set. All studies with original data that evaluated the occurrence of scalar translocation or tip fold-over (TF) with postoperative computed tomography (CT) following primary cochlear implantation in bilateral sensorineuronal hearing loss patients were considered to be eligible. Data were extracted independently by two reviewers. RESULTS: We included 33 studies, of which none were randomized controlled trials. Meta-analysis of five cohort studies comparing scalar translocation between lateral wall and perimodiolar arrays showed that lateral wall arrays have significantly lower translocation rates (7% vs. 43%; pooled odds ratio = 0.12). Translocation was negatively associated with speech perception scores (weighted mean 41% vs. 55%). Tip fold-over of the array was more frequent with perimodiolar arrays (X2  = 6.8, P < .01). CONCLUSIONS: Scalar translocation and tip fold-overs occurred more frequently with perimodiolar arrays than with lateral wall arrays. In addition, translocation of the array negatively affects hearing with the cochlear implant. Therefore, if one aims to minimize clinically relevant intracochlear trauma, lateral wall arrays would be the preferred option for cochlear implantation. Laryngoscope, 131:1358-1368, 2021.

Double Ring in Cochlear Otosclerosis: A Limit to Cochlear Implantation? The Solution Is the Surgical Approach.

We present a case of a 50-year patient with a severe form of otosclerosis (double ring) that was successfully implanted. We used a bone-anchored hearing implant for restoring the hearing in the right side and a cochlear implant in the left side; both surgeries did not show any complications. For reducing the risk of a secondary bone ossification related to the trauma of cochleostomy for electrode's insertion, we used a round window approach. The patient recovered a normal auditory threshold and normal speech perception capacity both in silence and noise conditions 1 year after surgery.

Phone Speech Recognition Improvement in Noisy Environment: Use of a Bluetooth Accessory.

OBJECTIVE: To evaluate speech understanding in noise and patient satisfaction using the new Cochlear Wireless Phone Clip device. MATERIAL AND METHODS: Twenty-nine experienced cochlear implant (CI) users (>6 months usage) were situated in a soundproof room where a 65 dB SPL Spanish cocktail noise was generated continuously from 4 loudspeakers. Lists of disyllabic words were presented through the clinic landline telephone to the patients. Patients were tested first holding the phone and then with the Cochlear Phone Clip© paired to the CP910 using various mixing ratios (2:1, 4:1, and Phone Clip© only). RESULTS: Statistically significant (P < .001) improvement of speech recognition performance was found in cell phone usage by wireless transmission and also when using this new device. Kepler questionnaire results showed that before using Phone Clip in everyday life, 55.2% of patients described themselves highly or greatly affected by their deafness for telephone use and 80% moderately to greatly affected. Kim questionnaire results showed statistically significant differences (P < .001) in the subjective satisfaction of the Bluetooth-implemented CI compared to the conventional mode for sound quality, noise interference, and sound accuracy. CONCLUSIONS: The wireless Phone Clip© device helps implanted people to improve subjective and objective speech recognition performance through the phone in noisy environments.

Acceptance and Benefits of Electro-Acoustic Stimulation for Conventional-Length Electrode Arrays.

BACKGROUND: Prior studies have shown an advantage for electro-acoustic stimulation (EAS) in cochlear implant (CI) patients with residual hearing, but the degree of benefit can vary. The objective was to explore which factors relate to performance with and acceptance of EAS for CI users with conventional-length electrodes. METHODS: A retrospective chart review was conducted for adults with an average threshold of 75 dB hearing loss or better across 250 and 500 Hz preoperatively (n = 83). All patients underwent cochlear implantation with a conventional-length electrode. Low-frequency audiometric thresholds were measured at initial activation as well as 3 and 12 months postoperatively to determine who met the criteria for EAS. Speech perception for CNC words and AzBio sentences in quiet and +10 dB SNR noise was evaluated 3 and 12 months after activation. RESULTS: Speech perception in quiet and noise was similar regardless of whether or not the patient was eligible for EAS. Less than half of the patients who met the EAS criteria chose to use it, citing reasons such as physical discomfort or lack of perceived benefit. EAS users performed better on CNC words but not sentence recognition than EAS nonusers. CONCLUSIONS: EAS use is dependent on audiologic and nonaudiologic issues. Hearing preservation is possible with conventional electrodes, but hearing preservation alone does not guarantee superior speech perception.

Preserved Cochlear Implant Function After Multiple Electroconvulsive Therapy Treatments.

This case report presents the successful use of multiple treatments of electroconvulsive therapy (ECT) in a patient with a cochlear implant (CI). A 60-year-old man with a left-sided CI and bipolar disorder presented with severe depression. A total of 9 separate sessions of unilateral ECT was administered to the contralateral side of the existing CI. We collected subjective, clinical, and audiological assessment of the patient and the CI prior, during, and after ECT therapy. The patient tolerated ECT well and there were no complications. Unilateral ECT was performed contralateral to the CI without any harm to the patient or implant. Laryngoscope, 131:E1695-E1698, 2021.

O uso do Sistema de Frequência Modulada por crianças e adolescentes atendidos em serviço de saúde auditiva / The use of system of Frequency Modulation by children and adolescents from a hearing health care service

RESUMO Objetivo Analisar o uso e os motivos para o não uso do Sistema de Frequência Modulada (FM) por crianças e adolescentes com perda auditiva e usuários de aparelhos de amplificação sonora individual (AASI) e/ou com implante coclear (IC). Métodos Foi aplicado um questionário em forma de entrevista, por meio de contato telefônico. As questões foram retiradas do questionário FM Listening Evaluation for Children, traduzido e adaptado para a língua portuguesa por Jacob et al. (2010) e denominado Avaliação do Sistema FM, bem como outras três perguntas elaboradas pelos pesquisadores. Resultados Foram entrevistados 87 pais/responsáveis, verificando-se que o sistema FM era utilizadopor menos da metade da amostra. Quanto à mediana de uso de horas diárias do sistema, observou-se diferença nos pacientes com FM no IC, que usavam o dispositivo por maior número de horas diárias, do que os usuários de AASI. Igualmente apresentou diferença estatística o principal motivo para onão uso, relacionado ao fato de os pacientes terem recebido novos AASI e/ou IC incompatíveis com a tecnologia obtida anteriormente. Ainda, os entrevistados gostariam que lhes fossem fornecidas melhores orientações. Conclusão a maior parte dos pacientes não utiliza o sistema FM, sendo o principal motivo o uso de novos AASI e/ou IC. Os pacientes com IC usam o FM de forma mais efetiva (diariamente).

ABSTRACT Purpose To analyze de use and reasons for not using of FM systems by children and adolescents with hearing loss and users of hearing aids (HA) and or cochlear implant (CI). Methods A questionnaire applied in the form of an a interview through telephone contact was used. The questions were removed from the questionnaire "FM Listening Evaluation for children", translated and adapted for Portuguese language by Jacob et al. (2010) and named "Avaliação do Sistema FM", and three other questions prepared by the researchers. Results 87 parents/guardians were interviewed, and it was verified that less than half of the sample used the FM system. As for the median use of the FM systems daily hours, there was a statistical difference in patients with FM in CI, Who used the device for a greater number of daily hours than hearing AID users. The main reason for non-use also presented statistical difference to the fact that patients have received new hearing aids and/or CI incompatible with previously obtained. Also, respondents would like the guidance provided improved. Conclusion Most patients did not use the FM system, the main reason being the usage of new hearing aids and/or CI. Patients with CI use FM more effectively (daily).

Electrophysiological effects of slim straight intracochlear electrode position.

OBJECTIVE: The electrical current distribution of a cochlear implant electrode within the cochlea is essential for post-operative hearing performance. The slim straight electrode is designed to enable the placement of contacts in a lateral or medial direction to the modiolus. The electrophysiological effect of this different contact direction is so far unknown. The aim of this study was to determine the influence of intracochlear laterally or medially directed electrode contacts on electrophysiological behaviour. METHOD: A slim straight electrode was inserted into the cochleae of five patients, and the neural response threshold was measured in a laterally and medially directed contact position. The cochleae in five temporal bone specimens were de-capped allowing an insertional observation of the contact position (lateral versus medial) of the electrode. RESULTS: There was no difference in neural response threshold between a lateral and a medial position of the contacts. Temporal bone study indicated no intracochlear torsion of the electrode. CONCLUSION: Our study provides evidence that the intracochlear position of slim straight electrode contacts does not affect the neural response threshold.

Implante coclear de titanio auditivo osteointegrado para hipoacusia mixta conductiva / Osseointegrated auditory titanium cochlear implant for mixed conductive hearing loss

INTRODUCCIÓN: Este documento técnico se realiza a solicitud del SIS. Las anomalías congénitas del oído son defectos de nacimiento que afectan la forma y posición de la oreja. Entre estas se encuentra la microtia. La mayoría de los niños con microtia tienen un oído interno de formación normal, pero carecen de todas o parte de las estructuras que forman el oído externo, incluida la abertura en algunos casos. a. Cuadro clínico Esta condición puede ocurrir en uno o ambos lados de la cabeza. Sin las estructuras externas para canalizar el sonido al oído interno, los niños a menudo tienen dificultades para oír y determinar la dirección del sonido. En algunos casos, existe una ausencia del canal auditivo externo. A esto se le llama atresia aural. b. Tecnología sanitaria Los Implantes Cocleares son dispositivos que estimulan eléctricamente el nervio auditivo y permiten que las personas con pérdidas auditivas profunda reconozcan el sonido. Este dispositivo consta de dos componentes, un componente interno con un receptor y electrodos que se implanta en el oído durante un procedimiento quirúrgico; y un componente externo con micrófono, procesador de voz y transmisor. Puede tener diferentes materiales, siendo el más común el titanio. OBJETIVO: Evaluar la eficacia y seguridad, así como documentos relacionados a la decisión de cobertura del implante coclear de titanio osteointegrado en pacientes con atresia aural u otra malformación de los oídos. METODOLOGÍA: Se realizó una búsqueda en las principales bases de datos bibliográficas: MEDLINE, LILACS, COCHRANE, así como en buscadores genéricos de Internet incluyendo Google Scholar y TRIPDATABASE para identificar revisiones sistemáticas (RS) y ensayos clínicos aleatorizados (ECAs). Adicionalmente, se hizo una búsqueda dentro de la información generada por las principales instituciones internacionales de otorrinolaringología y agencias de tecnologías sanitarias que realizan evaluación de tecnologías sanitarias (ETS), guías de práctica clínica (GPC) y evaluaciones económicas (EE). RESULTADOS: Se identifico una RS, un estudio comparativo observacional. Adicionalmente se incluyó un consenso de expertos, dos GPC y cuatro ETS. No se identificaron EE de la región. La RS(2013, Nadaraja et al.) comparó atresiaplastia (cirugía para atresia aural) versus el dispositivo de conducción ósea osteointegrado de titanio (BAHA ®) en pacientes con atresia aural congénita. La fecha de búsqueda fue desde 1975 al 2012. Para el análisis final se incluyeron 41 observacionales. De los oídos post atresiaplastia, el 73,8% (IC95%=62,2%-85,4%), tenían un umbral de recepción del habla (SRT, del inglés Speech Reception Threshold) inferior a 30 dB (338 oídos), el 60,3% (IC95%=45,8%-74,8%) tenían un promedio de tonos puros (PTA, del inglés Pure Tone Average) inferior a 30 dB (390 oídos), y el 68,9% (IC95%=59,4%-78,3%) tenía una ganancia auditiva o la brecha aire-hueso (ABG, del inglés air-bone gap) inferior a 30 dB (852 oídos). La ganancia auditiva promedio fue de 24,1 dB (IC95%=21,62-26,51) para 516 oídos. Los resultados auditivos se deterioraron con el tiempo. De los pacientes con dispositivo osteointegrado (BAHA®), el 95,9% (IC95%=91,5%-100,0%) tenían una PTA menor de 30 dB (77 oídos), y el 98,2% (IC95%=94,5%-100,0%) tenían una ABG menor que 30 dB (47 oídos); la ganancia auditiva promedio fue de 38,0 dB (IC del 95%, 33,14 y 45,22) en 100 oídos. Si bien se describen los resultados de la comparación, no se hace una estimación de la diferencia. De forma absoluta, se observa que el dispositivo osteointegrado tendría mejores desenlaces que la cirugía (atresioplastía). CONCLUSIONES: La evidencia con respecto al implante coclear osteointegrado de titanio para atresia aural u otras malformaciones congénitas es escasa y se basa en estudios observacionales. La evidencia comparativa es de baja calidad metodológica y evalúa a nuestra tecnología de interés versus cirugía de corrección de la atresia o no realizar intervenciones. Se evidencia que existe una mejoría en los desenlaces de eficacia en las personas que reciben implante coclear osteointegrado, así como los que se someten a la cirugía reconstructiva, sin embargo, el beneficio es mayor en el grupo que utiliza esta tecnología de interés. No se reportan diferencias en la seguridad o eventos serios asociados al uso de los implantes cocleares osteointegrados. Un consenso de expertos internacionales recomienda a los implantes cocleares de titanio osteointegrados para el manejo de atresia aural y dos GPC la consideran dentro de sus opciones de tratamiento para hipoacusia (sin mencionar específicamente a nuestra población objetivo). Las ETS recabadas coinciden en considerar al implante coclear osteointegrado como una opción terapéutica segura y beneficiosa para el paciente en el caso de hipoacusia, mientras que otra ETS la considera relevante para atresia aural u otras malformaciones del oído.

Aplicación de la tecnología de enrutamiento inalámbrico contralateral de la señal (CROS) en usuarios de implante coclear unilateral / Application of Wireless Contralateral Routing of Signal (CROS) Technology in Unilateral Cochlear Implant Users

INTRODUCCIÓN: La implantación unilateral en la hipoacusia profunda bilateral deja al paciente en una situación de audición monoaural, con los consiguientes problemas audiológicos, en especial por la incapacidad de percepción de la palabra en ambientes con ruido de fondo, por el efecto sombra de la cabeza. Se puede mejorar su rendimiento auditivo aprovechando los sistemas inalámbricos de enrutamiento de la señal (CROS), para dotarlos de una entrada de sonido bilateral. MÉTODO: Se estudiaron 12 usuarios unilaterales de implante coclear adultos, con experiencia con un procesador de sonido Naída CI Q70 que tiene capacidad de comunicación inalámbrica con el CROS. La comprensión del habla en cabina en silencio y en ruido se llevó a cabo utilizando como estímulos el test de oraciones grabadas en español en 3 condiciones: habla dirigida hacia el oído no implantado con y sin CROS activado y habla de frente con UltraZoom. Tras un mes de uso del dispositivo CROS, se evaluó la satisfacción del usuario utilizando cuestionarios. RESULTADOS: En silencio, la diferencia media entre el implante unilateral solo y el implante unilateral con el dispositivo CROS fue del 27,6%, mientras que en presencia de ruido fue del 32,5%. Si se comparan las puntuaciones entre presentar activada o no la opción UltraZoom al utilizar CROS, se demuestra un beneficio de un 35% de inteligibilidad. Todos los sujetos puntuaron su experiencia de uso como satisfactoria. CONCLUSIÓN: El dispositivo CROS utilizado con implante coclear unilateral produce un beneficio objetivo y subjetivo en el reconocimiento de la palabra cuando la señal se dirige hacia el mismo. En este estudio no se reprodujo la condición de presentación de la señal verbal en el oído implantado con ruido en el adaptado con el CROS por haberse demostrado previamente que la discriminación verbal se deteriora de forma importante con respecto al implante unilateral sin CROS

INTRODUCTION: Single cochlear implantation usually provides substantial speech intelligibility benefits but bilaterally deaf, unilaterally implanted subjects will continue to experience limitations due to the head shadow effect, like single-sided deaf individuals. In the treatment of individuals with single-sided deafness one option is contralateral routing of signal (CROS) devices, which constitute a non-surgical intervention of the second ear in unilaterally implanted individuals. METHOD: Twelve experienced adult cochlear implant users with Naída Q70 processor and the CROS device used in combination participated in the study. For the study 3 conditions were provided: cochlear implant only, omnidirectional microphone mode (CROS deactivated); cochlear implant plus CROS activated, omnidirectional microphone mode and cochlear implant plus CROS activated, UltraZoom mode. Speech reception thresholds were determined in quiet and noise. Subjective feedback regarding the practical usability of the CROS device and the perceived benefit were collected. RESULTS: There was a 27.6% improvement in speech understanding in quiet and 32.5% improvement in noise when CROS device was activated. Using advanced directional microphones, a statistically significant benefit of 35% was obtained. The responses to the questionnaires revealed that the subjects perceived benefit in their everyday lives when using the CROS device with their cochlear implants. CONCLUSION: The investigated CROS device used by unilateral CI recipients in cases where bilateral implantation is not an option provides both subjective and objective speech recognition benefit when the signal is directed to the CROS device. Unfavourable conditions where speech is presented from the cochlear implant side and noise from the CROS side or diffusely were not included in this evaluation since the CROS device adds additional noise and performance is expected to decrease as has previously been shown

Image-guided cochlear access by non-invasive registration: a cadaveric feasibility study.

Image-guided cochlear implant surgery is expected to reduce volume of mastoidectomy, accelerate recovery, and improve safety. The purpose of this study was to investigate the safety and effectiveness of image-guided cochlear implant surgery by a non-invasive registration method, in a cadaveric study. We developed a visual positioning frame that can utilize the maxillary dentition as a registration tool and completed the tunnels experiment on 5 cadaver specimens (8 cases in total). The accuracy of the entry point and the target point were 0.471 ± 0.276 mm and 0.671 ± 0.268 mm, respectively. The shortest distance from the margin of the tunnel to the facial nerve and the ossicular chain were 0.790 ± 0.709 mm and 1.960 ± 0.630 mm, respectively. All facial nerves, tympanic membranes, and ossicular chains were completely preserved. Using this approach, high accuracy was achieved in this preliminary study, suggesting that the non-invasive registration method can meet the accuracy requirements for cochlear implant surgery. Based on the above accuracy, we speculate that our method can also be applied to neurosurgery, orbitofacial surgery, lateral skull base surgery, and anterior skull base surgery with satisfactory accuracy.