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Objectives: One of the main elements of a fully implantable system is the totally implantable microphone (TIM). The Carina system uses a sub-cutaneous, omnidirectional microphone, which is surgically implanted on the mastoid bone behind the ear. The most frequently used TIM position is on the posterior inferior mastoid line, but due to anatomical reasons or surgeon's preference, it might also be positioned in other locations behind the ear. This may lead to variability in the directional response. Additionally, the retro-auricular microphone position does not seem ideal to pick up sounds from the front. The aim of this study was to investigate the directional response of the Carina TIM in various microphone positions on the mastoid to be able to make a judgement on which microphone position will be best for optimal speech discrimination. Materials & Methods: The Carina TIM was positioned in four different positions on two different artificial heads (Cochlear Haddock and Cortex MK2) and a human cadaveric whole head. The heads were placed in the middle of a horizontal arch with loudspeakers having a distance of 15° from each other. A broadband noise (MLS) with a duration of 1.5 s was played consecutively via the loudspeakers and recorded by the Carina TIM and a reference microphone. Results and Conclusions: The directivity index (DI) and directivity vector (DV) will be calculated for each microphone position on all heads. The DI and DV for the broadband signal as well as for the octave bands will be analyzed and compared for the various microphone positions. Differences between the artificial heads and the cadaver head will be presented. Preliminary results show differences in the DI and DV for the various microphone positions for both, the cadaver head and the artificial heads, which suggests that there is an optimal position for the TIM and that the microphone position may have an influence on the hearing performance. Polar plots with the different directional responses will be shown and discussed. [ABSTRACT FROM AUTHOR]

Audiological rehabilitation (AR) is important to improve auditory and communication skills of persons with hearing impairment (HI), in order to optimize participation in society. The complexity of encountered difficulties due to HI requires a holistic approach to AR, consisting of sensory management, auditory-cognitive training and counselling. Although the importance of providing a comprehensive AR program is widely acknowledged, the majority of people with HI is not entitled to it (e.g., people with SSD). Computerized AR offers an efficient, cost- and time-effective method for a large group of persons with disabling HI, adapted to their personal needs. We developed a prototype of the LUISTER AR e-health scheme that consists of an assessment battery to determine the communication status, a variety of linguistic auditory- cognitive exercises as well as a generic, non-linguistic training task and a binaural training task. We are currently evaluating the feasibility and usability of this prototype e-health scheme on a tablet in adults with SSD and a CI. These data will be presented, as well as on-task improvement and data logging of the intensity and frequency of training. [ABSTRACT FROM AUTHOR]

Objectives: Five transmission pathways are involved in bone conduction (BC) perception, of which the cochlea is the major contributor 1 . This contribution was confirmed by intracochlear pressure (ICP) measurements in chinchilla's and in one fresh-fresh frozen human temporal bone (TB) 2, 3 . The aim of this study is to evaluate an appropriate (reversible) fixation method to study BC transmission and to collect reference data to compute a standardized range. Results of intracochlear pressure measurements with BC stimulation on human temporal bones (TBs) are presented. Additionally relevant factors in relation to totally implantable systems such as CI will be discussed by the moderator. Methods: Four fresh-frozen human TBs, compliant to ASTM-standards, are used for the ICP experiment after surgical preparations. Sound stimulation is conducted either through an insert phone via an artificial ear canal (air conduction, AC) or via bone conduction stimulator. After drilling the cochleostomies (Ø 350 m) under saline, two fiber-optic pressure sensors (FOP-M260, FISO Technologies Inc.) are inserted in scala vestibuli (SV) and scala tympani (ST) followed by sealing with alginate and dental cement. Different conditions are investigated during the experiment for both AC and BC: normal, stapes fixation, incudo-stapedial-joint cut. Differential pressure between SV and ST is measured. Results & Conclusion: The use of alginate and dental cement and releasing the sensor from the micromanipulator was deemed the better fixation method, as sensor and promontory moved in phase and without relative motion. Relevance in relation to totally implantable systems will be presented during the session. References 1 S. Stenfelt and R. L. Goode, J. Acoust. Soc. Am., 2005 2 D. Chhan et al., Hear. Res., 2013 3 C. Stieger et al., AIP Conf. Proc., 2015 [ABSTRACT FROM AUTHOR]

A growing body of evidence suggests that musical activities can enhance the listening brain and develop executive functions, including Literacy. Empowering families of newly diagnosed babies and infants with a hearing loss, through early intervention home based support is proven to be beneficial. Music can captivate babies and allows them to explore and demonstrate their awareness of sound in an easy, more developmentally appropriate way, through body movements, facial expressions, vocalizations and playing instruments. Babies listen for predictable melodies and harmonies as found in lullabies (Barker & Macklinlay, 2006). The BabyBeats™ early intervention resource is a musical habilitation resource which was designed to help improve early parent- child bonding, listening behaviour, communication skills, and social emotional development, pre- and post-implantation. To give parents the opportunity to engage with their child in their daily routines a mobile application was created. The families visiting our centre used the app and audit data were collected based on a simple parental and professional questionnaire. The collected feedback was positive and ideas from the resource were carried over into the family's everyday routines. In the monitoring phase increased vocalization, attention, and anticipation of the activities were observed. Increased confidence in singing, moving, and playing with their baby was also reported by these families. These outcomes are encouraging as they support the aims of the musical rehabilitation resource and help the natural development of attachment, supporting babies and toddlers to build early developmental skills essential for later language development as they are waiting for a cochlear implant. [ABSTRACT FROM AUTHOR]

Objectives: Cochlear implantation (CI) in adult subjects with acquired single sided deafness (SSD) or asymmetric hearing loss (AHL) is investigated prospectively. Audiological performance is evaluated, as well as potential improvements of tinnitus and anxiety/depression. Materials and Methods: A multinational, multicenter, prospective study design was implemented with participating centers in Germany, Austria, and Belgium. Speech discrimination was tested in quiet, and in noise using an adaptive paradigm with the speech coming from the front and the noise from three different locations (either from the front, or the implant side, or the contralateral side). Tinnitus was evaluated by Visual Analogue Scale (VAS) and questionnaire, anxiety and depression by the Hospital Anxiety and Depression Scale (HAS). A pitch matching task was performed by some clinics, and localization abilities were also tested. Results and Conclusions: To date, 36 subjects from 7 clinics were included in the data analysis (mean age 53, range 18-81 years). No adverse events have been noted. After 3 months of CI use, a significant speech intelligibility benefit with the implant (noise on the contralateral side) was observed: 0.3 dB (N=23). The significant speech intelligibility benefit was maintained at 6 months (N=20) and increased to 1.75 dB (N=18) at 12 months. The tinnitus impairment decreased significantly by 2.5 points on the VAS after 3 months (N=26). A significant decrease of 2 points was maintained by 12 months (N=19). The tinnitus questionnaire was in line with this improvement. CI in subjects with SSD and AHL is able to improve speech discrimination in quiet and noise. Impairment by tinnitus decreased significantly. These benefits were apparent as short as 3 months after implantation and persisted with time. As CI is a safe procedure, it should continue to be considered in subjects with unilateral or asymmetric hearing loss. [ABSTRACT FROM AUTHOR]

We report a case of a severe ear infection in a 35-year-old man treated with ixekizumab for psoriasis. Ixekizumab is a humanized monoclonal antibody that selectively prevents the interaction between interleukin 17 A and its receptor. Biologicals like ixekizumab are used to achieve symptom relief in autoimmune diseases including psoriasis. Unlike the mild upper respiratory tract infections usually described as side-effects of this treatment, we report a case of a patient who presented with a severe otitis media, complicated with a facial paresis and nasopharyngeal abscess. To the best of our knowledge, this is the first case presenting a severe, complicated ear infection as a possible side effect of ixekizumab. We conclude that when using ixekizumab, vigilance for upper airway infections is needed and if necessary, interruption of therapy should be considered. However, further research is needed to confirm this hypothesis., (© 2024. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

The round window (RW) membrane plays an important role in normal inner ear mechanics. Occlusion or reinforcement of the RW has been described in the context of congenital anomalies or after cochlear implantation and is applied as a surgical treatment for hyperacusis. Multiple lumped and finite element models predict a low-frequency hearing loss with air conduction of up to 20 dB after RW reinforcement and limited to no effect on hearing with bone conduction stimulation. Experimental verification of these results, however, remains limited. Here, we present an experimental study measuring the impact of RW reinforcement on the middle and inner ear mechanics with air and bone conduction stimulation. In a within-specimen repeated measures design with human cadaveric specimens (n = 6), we compared the intracochlear pressures in scala vestibuli (P SV ) and scala tympani (P ST ) before and after RW reinforcement with soft tissue, cartilage, and bone cement. The differential pressure (P DIFF ) across the basilar membrane - known to be closely related to the hearing sensation - was calculated as the complex difference between P SV and P ST . With air conduction stimulation, both P SV and P ST increased on average up to 22 dB at frequencies below 1500 Hz with larger effect sizes for P ST compared to P SV . The P DIFF , in contrast, decreased up to 11 dB at frequencies between 700 and 800 Hz after reinforcement with bone cement. With bone conduction, the average within-specimen effects were less than 5 dB for either P SV , P ST, or P DIFF . The inter-specimen variability with bone conduction, however, was considerably larger than with air conduction. This experimental study shows that RW reinforcement impacts air conduction stimulation at low frequencies. Bone conduction stimulation seems to be largely unaffected. From a clinical point of view, these results support the hypothesis that delayed loss of air conduction hearing after cochlear implantation could be partially explained by the impact of RW reinforcement., (Copyright © 2024 The Author(s). Published by Elsevier B.V. All rights reserved.)

Objectives: Assessing listening difficulties and associated complaints can be challenging. Often, measures of peripheral auditory functions are within normal ranges, making clinicians feel unsure about proper management strategies. The range and nature of observed or experienced difficulties might be better captured using a qualitative measure. The Evaluation of Children's Listening and Processing Skills (ECLiPS) questionnaire was designed to broadly profile the auditory and cognitive problems often present in children with listening difficulties. This 38-item questionnaire was initially standardized in British children aged 6 to 11 years, was subsequently modified for use with North-American children, and was recently translated into Flemish-Dutch. This study aimed to compare typical scores of the Flemish version with the UK and US versions, and to evaluate and compare its psychometric quality based on Rasch analysis., Design: We selected 112 Flemish children aged 6 to 11 years with verified normal hearing and typical development, and asked two caregivers of every child to fill out the ECLiPS. Data from two comparator samples were analyzed, including responses for 71 North-American children and 650 British children. Typical values for ECLiPS factors and aggregates were determined as a function of age and gender, and meaningful differences across samples were analyzed. Rasch analyses were performed to evaluate whether ECLiPS response categories work as intended, and whether item scores fit a linear equal interval measurement scale that works the same way for everyone. Item and person metrics were derived, including separation and reliability indices. We investigated whether items function similarly across linguistically and culturally different samples., Results: ECLiPS scores were relatively invariant to age. Girls obtained higher scores compared with boys, mainly for items related to memory and attention, and pragmatic and social skills. Across ECLiPS versions, the most pronounced differences were found for items probing social skills. With respect to its psychometric quality, ECLiPS response categories work as intended, and ECLiPS items were found to fit the Rasch measurement scale. Cultural differences in responses were noted for some items, belonging to different factors. Item separation and reliability indices generally pointed toward sufficient variation in item difficulty. In general, person separation (and reliability) metrics, quantifying the instrument's ability to distinguish between poor and strong performers (in a reproducible manner), were low. This is expected from samples of typically developing children with homogeneous and high levels of listening ability., Conclusions: Across the languages assessed here, the ECLiPS caregiver questionnaire was verified to be a psychometrically valid qualitative measure to assess listening and processing skills, which can be used to support the assessment and management of elementary school children referred with LiD., Competing Interests: The authors have no conflicts of interest to disclose., (Copyright © 2024 The Authors. Ear & Hearing is published on behalf of the American Auditory Society, by Wolters Kluwer Health, Inc.)

Robotic devices have recently enhanced cochlear implantation by improving precision resulting in reduced intracochlear damage during electrode insertion. This study aimed to gain first insights into the expected dimensions of the cone-like workspace from the posterior tympanotomy towards the round window membrane. This retrospective chart review analyzed ten postoperative CT scans of adult patients who were implanted with a CI in the past ten years. The dimensions of the cone-like workspace were determined using four landmarks (P1-P4). In the anteroposterior range, P1 and P2 were defined on the edge of the bony layer over the facial nerve and chorda tympani nerve, respectively. In the inferosuperior range, P3 was defined on the bony edge of the incus buttress and P4 was obtained at a distance of 0.45 mm between the facial nerve and the chorda tympani nerve. After selecting the landmarks, the calculations of the dimensions of the surgical access space were done in a standardized coordinate system and presented using descriptive statistics. The cone-like space is limited by two maximal angles, α and β . The average angle α of 19.84 (±3.55) degrees defines the angle towards the round window membrane between P1 and P2. The second average angle β of 53.56 (±10.29) degrees defines the angle towards the round window membrane between P3 and P4. Based on the angles the mean anteroposterior range of 2.25 (±0.42) mm and mean inferosuperior range of 6.73 (±2.42) mm. The distance from the posterior tympanotomy to the round window membrane was estimated at 6.05 (±0.71) mm. These findings present data on the hypothetical maximum workspace in which a future robotically steered insertion tool can be positioned for an optimal automated electrode insertion. A larger sample size is necessary before generalizing these dimensions to a population. Further research including preoperative CT scans is needed for planning robotic-steered cochlear implantation., Competing Interests: The authors declare the following financial interests/personal relationships which may be considered as potential competing interests: Maarten Schoovaerts reports financial support was provided by Research Foundation 10.13039/501100011878Flanders. Nicolas Verhaert reports financial support was provided by Research Foundation 10.13039/501100011878Flanders. Alexander Geerardyn reports financial support was provided by Research Foundation 10.13039/501100011878Flanders. If there are other authors, they declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (© 2024 The Authors.)

People with single-sided deafness (SSD) or asymmetric hearing loss (AHL) have particular difficulty understanding speech in noisy listening situations and in sound localization. The objective of this multicenter study is to evaluate the effect of a cochlear implant (CI) in adults with single-sided deafness (SSD) or asymmetric hearing loss (AHL), particularly regarding sound localization and speech intelligibility with additional interest in electric-acoustic pitch matching. A prospective longitudinal study at 7 European tertiary referral centers was conducted including 19 SSD and 16 AHL subjects undergoing cochlear implantation. Sound localization accuracy was investigated in terms of root mean square error and signed bias before and after implantation. Speech recognition in quiet and speech reception thresholds in noise for several spatial configurations were assessed preoperatively and at several post-activation time points. Pitch perception with CI was tracked using pitch matching. Data up to 12 months post activation were collected. In both SSD and AHL subjects, CI significantly improved sound localization for sound sources on the implant side, and thus overall sound localization. Speech recognition in quiet with the implant ear improved significantly. In noise, a significant head shadow effect was found for SSD subjects only. However, the evaluation of AHL subjects was limited by the small sample size. No uniform development of pitch perception with the implant ear was observed. The benefits shown in this study confirm and expand the existing body of evidence for the effectiveness of CI in SSD and AHL. Particularly, improved localization was shown to result from increased localization accuracy on the implant side.

Objectives: Increased neonatal referral rate of conductive hearing loss (CHL) related to otitis media with effusion (OME) following universal neonatal hearing screening (UNHS) may cause an unnecessary clinical, emotional, and financial burden. This study analyzes the long-term, audiological, and medical characteristics of CHL associated with OME in neonates in order to establish a standardized protocol following technology-driven improvements in detection and referral rates in UNHS., Methods: A retrospective study of all neonates with OME-related CHL referred to the University Hospital of Leuven (Belgium) after failing UNHS with the MAICO devices between January 1, 2013 and December 31, 2021 was performed. Follow-up consultations, auditory tests, referral side, birth month, hearing loss degree, underlying pathologies and risk factors, time to normalization, and need for ventilation tubes were assessed., Results: The incidence of CHL related to OME was stable between 2013 and 2021. Of all referred infants with OME, 52.3 % demonstrated spontaneous recovery. The average time to hearing normalization was significantly longer in children with underlying congenital pathologies compared to those without. Moreover, 74.4 % of these children received ventilation tubes compared to 32.0 % of children without underlying pathologies. No correlation was found between the incidence of OME-related CHL with either a hearing loss degree, admission to neonatal intensive care, or history of a nasogastric feeding tube., Conclusions: In children who failed UNHS due to OME, hearing recovers spontaneously without surgical intervention in 2/3 of the infants without underlying conditions within one year. In children with underlying congenital disorders, the time to hearing recovery is longer and the risk for surgical intervention is higher, underlining the need for implementing a UNHS standardized protocol., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier B.V. All rights reserved.)

Purpose:  Vestibular implant electrode positioning close to the afferent nerve fibers is considered to be key for effective and selective electrical stimulation. However, accurate positioning of vestibular implant electrodes inside the semicircular canal ampullae is challenging due to the inability to visualize the target during the surgical procedure. This study investigates the accuracy of a new surgical protocol with real-time fluoroscopy and intraoperative CT imaging, which facilitates electrode positioning during vestibular implant surgery., Methods:  Single-center case-controlled cohort study with a historic control group at a tertiary referral center. Patients were implanted with a vestibulocochlear implant, using a combination of intraoperative fluoroscopy and cone beam CT imaging. The control group consisted of five patients who were previously implanted with the former implant prototype, without the use of intraoperative imaging. Electrode positioning was analyzed postoperatively with a high-resolution CT scan using 3D slicer software. The result was defined as accurate if the electrode position was within 1.5 mm of the center of the ampulla., Results: With the new imaging protocol, all electrodes could be positioned within a 1.5 mm range of the center of the ampulla. The accuracy was significantly higher in the study group with intraoperative imaging (21/21 electrodes) compared to the control group without intraoperative imaging (10/15 electrodes), (p = 0.008)., Conclusion:  The combined use of intraoperative fluoroscopy and CT imaging during vestibular implantation can improve the accuracy of electrode positioning. This might lead to better vestibular implant performance., (© 2024. The Author(s).)

The aim of this article is to determine the efficacy of otoendoscopy during microscopic cholesteatoma surgery on residual cholesteatoma rates postoperatively. The medical records of patients (aged 4-90) with primary acquired cholesteatoma who underwent microscopic cholesteatoma surgery (exclusively transcanal approach or canal wall-up tympano-mastoidectomy) with subsequent otoendoscopic examination (80 ears) for intraoperative cholesteatoma residues were retrospectively reviewed. All cases with mixed microscopic/endoscopic, fully endoscopic, or fully microscopic dissection were excluded, as well as cases where a canal wall-down technique was used. After microscopic cholesteatoma removal, the otoendoscope was used to inspect the middle ear recesses for intraoperative cholesteatoma residues. The intra- and postoperative cholesteatoma residue rate were evaluated. On endoscopic examination, intraoperative cholesteatoma residues were encountered in 24 patients (30%). A total of 30 foci were detected. Most of them were found in the superior retrotympanum (15 foci). In 9 cases an antral remnant guided the surgeon to convert to a canal wall up tympanomastoidectomy. During the postoperative follow-up period, residual cholesteatoma was detected on postoperative magnetic resonance imaging in 6 patients (7.5%). Adding an otoendoscopic examination to microscopic cholesteatoma surgery reduced the postoperative cholesteatoma residues rate (odds ratio=0.16). A negative otoendoscopic examination led to a cholesteatoma residue-free follow-up period in 95% of cases(NPV=0.95). Otoendoscopy is effective in identifying intraoperative cholesteatoma residues after microscopic cholesteatoma surgery. It reduces the postoperative cholesteatoma residue rate, and a negative otoendoscopic examination increases the likelihood of a cholesteatoma residue-free follow-up.

Purpose: The small size of the cochlea, and its location deeply embedded in thick temporal bone, poses a challenge for intra-cochlear guidance and diagnostics. Current radiological imaging techniques are not able to visualize the cochlear microstructures in detail. Rotational optical coherence tomography (OCT) fibers show great potential for intra-cochlear guidance. The generated images could be used to map, and study, the tiny cochlear microstructures relevant for hearing., Methods: This work describes the design of a rotational OCT probe with an outer diameter of 0.9 mm. It further discusses a robotic system, which features a remote center of motion mechanism, dedicated to the probe's positioning, fine manipulation and stable insertion into the cochlear micro-spaces. Furthermore, the necessary calibration steps for 3D reconstruction are described, followed by a detailed quantitative analysis, comparing the 3D reconstructions using a synthetic, 2:1 scaled scala tympani model with a reconstruction from micro-CT, serving as the ground truth. Finally, the potential of the system is demonstrated by scanning a single ex vivo cadaveric human cochlea., Results: The study investigates five insertions in the same 2:1 scaled tympani model, along with their corresponding 3D reconstruction. The comparison with micro-CT results in an average root-mean-square error of 74.2 µm, a signed distance error of 38.1 µm and a standard deviation of 63.6 µm. The average F-score of the reconstructions, using a distance threshold of 100 and 74.2 µm, resulted in 83.0% and 71.8%, respectively. Insertion in the cadaveric human cochlea showed the challenges for straight insertion, i.e., navigating the hook region., Conclusion: Overall, the system shows great potential for intra-cochlear guidance and diagnostics, due to the system's capability for precise and stable insertion into the basal turn in the scala tympani. The system, combined with the calibration procedure, results in detailed and precise 3D reconstructions., (© 2024. CARS.)

The study evaluates the accuracy of predicting intracochlear pressure during bone conduction stimulation using promontory velocity and ear canal pressure, as less invasive alternatives to intracochlear pressure. Stimulating with a percutaneous bone conduction device implanted in six human cadaveric ears, measurements were taken across various intensities, frequencies, and stimulation positions. Results indicate that intracochlear pressure linearly correlates with ear canal pressure ( R 2  = 0.43, RMSE = 6.85 dB), and promontory velocity ( R 2  = 0.47, RMSE = 6.60 dB). Normalizing data to mitigate the influence of stimulation position leads to a substantial improvement in these correlations. R 2 values increased substantially to 0.93 for both the ear canal pressure and the promontory velocity, with RMSE reduced considerably to 2.02 (for ear canal pressure) and 1.94 dB (for promontory velocity). Conclusively, both ear canal pressure and promontory velocity showed potential in predicting intracochlear pressure and the prediction accuracy notably enhanced when accounting for stimulation position. Ultimately, these findings advocate for the continued use of intracochlear pressure measurements to evaluate future bone conduction devices and illuminate the role of stimulation position in influencing the dynamics of bone conduction pathways., Competing Interests: GF is employed by Cochlear Ltd. The remaining authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2024 Wils, Geerardyn, Putzeys, Fierens, Denis and Verhaert.)

Hypothesis: Trauma to the osseous spiral lamina (OSL) or spiral ligament (SL) during cochlear implant (CI) insertion segregates with electrode type and induces localized intracochlear ossification and fibrosis., Background: The goal of atraumatic CI insertion is to preserve intracochlear structures, limit reactive intracochlear tissue formation, and preserve residual hearing. Previous qualitative studies hypothesized a localized effect of trauma on intracochlear tissue formation; however, quantitative studies failed to confirm this., Methods: Insertional trauma beyond the immediate insertion site was histologically assessed in 21 human temporal bones with a CI. Three-dimensional reconstructions were generated and virtually resectioned perpendicular to the cochlear spiral at high resolution. The cochlear volume occupied by ossification or fibrosis was determined at the midpoint of the trauma and compared with regions proximal and distal to this point., Results: Seven cases, all implanted with precurved electrodes, showed an OSL fracture beyond the immediate insertion site. Significantly more intracochlear ossification was observed at the midpoint of the OSL fracture, compared with the -26 to -18 degrees proximal and 28 to 56 degrees distal to the center. No such pattern was observed for fibrosis. In the 12 cases with a perforation of the SL (9 straight and 3 precurved electrodes), no localized pattern of ossification or fibrosis was observed around these perforations., Conclusion: OSL fractures were observed exclusively with precurved electrodes in this study and may serve as a nidus for localized intracochlear ossification. Perforation of the SL, in contrast, predominantly occurred with straight electrodes and was not associated with localized ossification., Competing Interests: The other coauthors have no conflict of interest to declare., (Copyright © 2024, Otology & Neurotology, Inc.)

Objectives: Current surgical techniques aim to preserve intracochlear structures during cochlear implant (CI) insertion to maintain residual cochlear function. The optimal technique to minimize damage, however, is still under debate. The aim of this study is to histologically compare insertional trauma and intracochlear tissue formation in humans with a CI implanted via different insertion techniques., Methods: One recent temporal bone from a donor who underwent implantation of a full-length CI (576°) via round window (RW) insertion was compared with nine cases implanted via cochleostomy (CO) or extended round window (ERW) approach. Insertional trauma was assessed on H&E-stained histological sections. 3D reconstructions were generated and virtually re-sectioned to measure intracochlear volumes of fibrosis and neo-ossification., Results: The RW insertion case showed electrode translocation via the spiral ligament. 2/9 CO/ERW cases showed no insertional trauma. The total volume of the cochlea occupied by fibro-osseous tissue was 10.8% in the RW case compared with a mean of 30.6% (range 8.7%-44.8%, N = 9) in the CO/ERW cases. The difference in tissue formation in the basal 5 mm of scala tympani, however, was even more pronounced when the RW case (12.3%) was compared with the cases with a CO/ERW approach (mean of 93.8%, range 81% to 100%, N = 9)., Conclusions: Full-length CI insertions via the RW can be minimally traumatic at the cochlear base without inducing extensive fibro-osseous tissue formation locally. The current study further supports the hypothesis that drilling of the cochleostomy with damage to the endosteum incites a local tissue reaction., Level of Evidence: 4: Case-control study Laryngoscope, 134:945-953, 2024., (© 2023 The American Laryngological, Rhinological and Otological Society, Inc.)

Hearing impairment constitutes a significant health problem in developed countries. If hearing loss is slowly progressive, the first signs may not be noticed in time, or remain untreated until the moment the auditory dysfunction becomes more apparent. The present study will focus on DFNA9, an autosomal dominant disorder caused by pathogenic variants in the COCH gene. Although several cross-sectional studies on this topic have been conducted, a crucial need for longitudinal research has been reported by many authors. Longitudinal trajectories of individual hearing thresholds were established as function of age and superimposed lowess curves were generated for 101 female and male carriers of the p.Pro51Ser variant. The average number of times patients have been tested was 2.49 years with a minimum of 1 year and a maximum of 4 years. In addition, interaural and sex differences were studied, as they could modify the natural evolution of the hearing function. The current study demonstrates that, both in female carriers and male carriers, the first signs of hearing decline, i.e. hearing thresholds of 20 dB HL, become apparent as early as the 3rd decade in the highest frequencies. In addition, a rapid progression of SNHL occurs between 40 and 50 years of age. Differences between male and female carriers in the progression of hearing loss are most obvious between the age of 50 and 65 years. Furthermore, interaural discrepancies also manifest from the age of 50 years onwards. High-quality prospective data on the long-term natural evolution of hearing levels offer the opportunity to identify different disease stages in each cochlea and different types of evolution. This will provide more insights in the window of opportunity for future therapeutic intervention trials., (© 2024. The Author(s).)

Lumped element models facilitate investigating the fundamental mechanisms of human ear sound conduction. This systematic review aims to guide researchers to the optimal model for the investigated parameters. For this purpose, the literature was reviewed up to 12 July 2023, according to the PRISMA guidelines. Seven models are included via database searching, and another 19 via cross-referencing. The quality of the models is assessed by comparing the predicted middle ear transfer function, the tympanic membrane impedance, the energy reflectance, and the intracochlear pressures (ICPs) (scala vestibuli, scala tympani, and differential) with experimental data. Regarding air conduction (AC), the models characterize the pathway from the outer to the inner ear and accurately predict all six aforementioned parameters. This contrasts with the few existing bone conduction (BC) models that simulate only a part of the ear. In addition, these models excel at predicting one observable parameter, namely, ICP. Thus, a model that simulates BC from the coupling site to the inner ear is still lacking and would increase insights into the human ear sound conduction. Last, this review provides insights and recommendations to determine the appropriate model for AC and BC implants, which is highly relevant for future clinical applications., (© 2023 Author(s). All article content, except where otherwise noted, is licensed under a Creative Commons Attribution (CC BY) license (http://creativecommons.org/licenses/by/4.0/).)

A cochlear implant is a neuroprosthetic device that can restore speech perception for people with severe to profound hearing loss. Because of recent evolutions, a growing number of people with a cochlear implant have useful residual acoustic hearing. While combined electro-acoustic stimulation has been shown to improve speech perception for this group of people, some studies report limited adoption rates. Here, we present electro-vibrational stimulation as an alternative combined stimulation strategy that similarly targets the full cochlear reserve. This novel strategy combines the electrical stimulation by the cochlear implant with low-frequency bone conduction stimulation. In a first evaluation of electro-vibrational stimulation, speech perception in noise was assessed in 9 subjects with a CI and symmetrical residual hearing. We demonstrate a statistically significant and clinically relevant improvement for speech perception in noise of 1.9 dB signal-to-noise ratio. This effect was observed with a first prototype that provides vibrational stimulation to both ears with limited transcranial attenuation. Future integration of electro-vibrational stimulation into one single implantable device could ultimately allow cochlear implant users to benefit from their low-frequency residual hearing without the need for an additional insert earphone., (© 2023. The Author(s).)

Objectives: Audiological rehabilitation includes sensory management, auditory training (AT), and counseling and can alleviate the negative consequences associated with (untreated) hearing impairment. AT aims at improving auditory skills through structured analytical (bottom-up) or synthetic (top-down) listening exercises. The evidence for AT to improve auditory outcomes of postlingually deafened adults with a cochlear implant (CI) remains a point of debate due to the relatively limited number of studies and methodological shortcomings. There is a general agreement that more rigorous scientific study designs are needed to determine the effectiveness, generalization, and consolidation of AT for CI users. The present study aimed to investigate the effectiveness of a personalized AT program compared to a nonpersonalized Active Control program with adult CI users in a stratified randomized controlled clinical trial., Design: Off-task outcomes were sentence understanding in noise, executive functioning, and health-related quality of life. Participants were tested before and after 16 weeks of training and after a further 8 months without training. Participant expectations of the training program were assessed before the start of training., Results: The personalized and nonpersonalized AT programs yielded similar results. Significant on-task improvements were observed. Moreover, AT generalized to improved speech understanding in noise for both programs. Half of the CI users reached a clinically relevant improvement in speech understanding in noise of at least 2 dB SNR post-training. These improvements were maintained 8 months after completion of the training. In addition, a significant improvement in quality of life was observed for participants in both treatment groups. Adherence to the training programs was high, and both programs were considered user-friendly., Conclusions: Training in both treatments yielded similar results. For half of the CI users, AT transferred to better performance with generalization of learning for speech understanding in noise and quality of life. Our study supports the previous findings that AT can be beneficial for some CI users., Competing Interests: The authors have no conflicts of interest to disclose., (Copyright © 2022 Wolters Kluwer Health, Inc. All rights reserved.)

Foreign body response (FBR), inflammation, and fibrotic encapsulation of neural implants remain major problems affecting the impedance of the electrode-tissue interface and altering the device performance. Adhesion of proteins and cells (e.g., pro-inflammatory macrophages, and fibroblasts) triggers the FBR cascade and can be diminished by applying antifouling coatings onto the implanted devices. In this paper, we report the deposition and characterization of a thin (±6 nm) sulfobetaine-based coating onto microfabricated platinum electrodes and cochlear implant (CI) electrode arrays. We found that this coating has stable cell and protein-repellent properties, for at least 31 days in vitro, not affected by electrical stimulation protocols. Additionally, its effect on the electrochemical properties relevant to stimulation (i.e., impedance, charge injection capacity) was negligible. When applied to clinical CI electrode arrays, the film was successful at inhibiting fibroblast adhesion on both the silicone packaging and the platinum/iridium electrodes. In vitro, in fibroblast cultures, coated CI electrode arrays maintained impedance values up to five times lower compared to non-coated devices. Our studies demonstrate that such thin sulfobetaine containing layers are stable and prevent protein and cell adhesion in vitro and are compatible for use on CI electrode arrays. Future in vivo studies should be conducted to investigate its ability to mitigate biofouling, fibrosis, and the resulting impedance changes upon long-term implantation in vivo., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 Elsevier B.V. All rights reserved.)

The risk of insertion trauma in cochlear implantation is determined by the interplay between individual cochlear anatomy and electrode insertion mechanics. Whereas patient anatomy cannot be changed, new surgical techniques, devices for cochlear monitoring, drugs, and electrode array designs are continuously being developed and tested, to optimize the insertion mechanics and prevent trauma. Preclinical testing of these developments is a crucial step in feasibility testing and optimization for clinical application. Human cadaveric specimens allow for the best simulation of an intraoperative setting. However, their availability is limited and it is not possible to conduct repeated, controlled experiments on the same sample. A variety of artificial cochlear models have been developed for electrode insertion studies, but none of them were both anatomically and mechanically representative for surgical insertion into an individual cochlea. In this study, we developed anatomically representative models of the scala tympani for surgical insertion through the round window, based on microCT images of individual human cochleae. The models were produced in transparent material using commonly-available 3D printing technology at a desired scale. The anatomical and mechanical accuracy of the produced models was validated by comparison with human cadaveric cochleae. Mechanical evaluation was performed by recording insertion forces, counting the number of inserted electrodes and grading tactile feedback during manual insertion of a straight electrode by experienced cochlear implant surgeons. Our results demonstrated that the developed models were highly representative for the anatomy of the original cochleae and for the insertion mechanics in human cadaveric cochleae. The individual anatomy of the produced models had a significant impact on the insertion mechanics. The described models have a promising potential to accelerate preclinical development and testing of atraumatic insertion techniques, reducing the need for human cadaveric material. In addition, realistic models of the cochlea can be used for surgical training and preoperative planning of patient-tailored cochlear implantation surgery., Competing Interests: Declaration of competing interest The authors declare no conflict of interest., (Copyright © 2023 Elsevier B.V. All rights reserved.)

Cochlear implant restores hearing loss through electrical stimulation of the hearing nerve from within the cochlea. Unfortunately, surgical implantation of this neuroprosthesis often traumatizes delicate intracochlear structures, resulting in loss of residual hearing and compromising hearing in noisy environments and appreciation of music. To avoid cochlear trauma, insertion techniques and devices have to be adjusted to the cochlear microanatomy. However, existing techniques were unable to achieve a representative visualization of the human cochlea: classical histology damages the tissues and lacks 3D perspective; standard microCT fails to resolve the cochlear soft tissues; and previously used X-ray contrast-enhancing staining agents are destructive. In this study, we overcame these limitations by performing contrast-enhanced microCT imaging (CECT) with a novel polyoxometalate staining agent Hf-WD POM. With Hf-WD POM-based CECT, we achieved nondestructive, high-resolution, simultaneous, 3D visualization of the mineralized and soft microstructures in fresh-frozen human cochleae. This enabled quantitative analysis of the true intracochlear dimensions and led to anatomical discoveries, concerning surgically-relevant microstructures: the round window membrane, the Rosenthal's canal and the secondary spiral lamina. Furthermore, we demonstrated that Hf-WD POM-based CECT enables quantitative assessment of these structures as well as their trauma., (© 2023. The Author(s).)

The use of two types of speech-in-noise (SPIN) assessment, namely digits-in-noise self-tests and open-set, monosyllabic word tests, to assess the SPIN understanding performance of children with cochlear implants (CI) in mainstream and special education, was investigated. The tests' feasibility and reliability and the influence of specific cognitive abilities on their results were studied. The results of 30 children with CIs in mainstream and special education were compared to those of 60 normal-hearing children in elementary school. Results indicate that the digit triplet test (DTT) was feasible for all children tested in this study, as seen by the familiarity of all the digits, the high stability of the test results (<3 dB SNR), and a small measurement error (≤2 dB SNR). Remembering full triplets did not form a problem and results did not show systematic attention loss. For children with CIs, the performance on the DTT was strongly related to the performance on the open-set monosyllabic word-in-noise task. However, small but significant differences were observed in the performance of children with CIs in mainstream and special education on the monosyllabic word test. Both tests showed little influence of cognitive abilities, making them both useful in situations where the bottom-up auditory aspect of SPIN performance needs to be investigated or in situations where sentence-in-noise tests are too challenging.

Advancements in intracochlear diagnostics, as well as prosthetic and regenerative inner ear therapies, rely on a good understanding of cochlear microanatomy. The human cochlea is very small and deeply embedded within the densest skull bone, making nondestructive visualization of its internal microstructures extremely challenging. Current imaging techniques used in clinical practice, such as MRI and CT, fall short in their resolution to visualize important intracochlear landmarks, and histological analysis of the cochlea cannot be performed on living patients without compromising their hearing. Recently, optical coherence tomography (OCT) has been shown to be a promising tool for nondestructive micrometer resolution imaging of the mammalian inner ear. Various studies performed on human cadaveric tissue and living animals demonstrated the ability of OCT to visualize important cochlear microstructures (scalae, organ of Corti, spiral ligament, and osseous spiral lamina) at micrometer resolution. However, the interpretation of human intracochlear OCT images is non-trivial for researchers and clinicians who are not yet familiar with this novel technology. In this study, we present an atlas of intracochlear OCT images, which were acquired in a series of 7 fresh and 10 fresh-frozen human cadaveric cochleae through the round window membrane and describe the qualitative characteristics of visualized intracochlear structures. Likewise, we describe several intracochlear abnormalities, which could be detected with OCT and are relevant for clinical practice.

In cochlear implant surgery, insertion of perimodiolar electrode arrays into the scala tympani can be complicated by trauma or even accidental translocation of the electrode array within the cochlea. In patients with partial hearing loss, cochlear trauma can not only negatively affect implant performance, but also reduce residual hearing function. These events have been related to suboptimal positioning of the cochlear implant electrode array with respect to critical cochlear walls of the scala tympani (modiolar wall, osseous spiral lamina and basilar membrane). Currently, the position of the electrode array in relation to these walls cannot be assessed during the insertion and the surgeon depends on tactile feedback, which is unreliable and often comes too late. This study presents an image-guided cochlear implant device with an integrated, fiber-optic imaging probe that provides real-time feedback using optical coherence tomography during insertion into the human cochlea. This novel device enables the surgeon to accurately detect and identify the cochlear walls ahead and to adjust the insertion trajectory, avoiding collision and trauma. The functionality of this prototype has been demonstrated in a series of insertion experiments, conducted by experienced cochlear implant surgeons on fresh-frozen human cadaveric cochleae., (© 2022. The Author(s).)

Objective: We aim to compare the modified Veau-Wardill-Kilner push-back technique (VWK) and the Sommerlad intravelar veloplasty (Sommerlad IVVP) in terms of middle ear outcomes and oronasal fistulae frequency in three years old children., Methods: For this retrospective cohort study, data were collected and anonymized from consecutive patients with cleft palate (with or without cleft lip) who underwent surgery in our hospital between January 2008 and December 2018. Patients with syndromic diagnoses and patients who underwent surgical treatment elsewhere were excluded. We collected data from 101 children (202 ears) regarding middle ear complications at the age of three, including acute otitis media, middle ear effusion, tympanic membrane retraction, tympanic membrane perforation, tympanic membrane atelectasis and chronic otitis media with cholesteatoma. In addition, the presence of oronasal fistulae and the number of ventilation tubes received by the age of three were recorded., Results: The odds of children having a normal middle ear evaluation were 3.07 (95% Confidence interval (95%CI): [1.52, 6.12]; p < 0.05) times higher when children received Sommerlad IVVP compared to modified VWK. With 40.7% compared to 26.7%, a significantly higher incidence of middle ear effusion was present in the modified VWK group compared to Sommerlad IVVP (X 2 (1) = 4.38, p < 0.05). Furthermore, this group needed significantly more ventilation tube reinsertions (X 2 (2) = 12.22, p < 0.05) and was found to have a significantly higher incidence of oronasal fistula (53.5% vs. 17.2%, X 2 (1) = 14.75, p < 0.05). The latter was significantly associated with a higher need for ventilation tube reinsertion (X 2 (1) = 7.34, p < 0.05)., Conclusion: This study shows superior middle ear outcomes and fewer oronasal fistulae after Sommerlad IVVP compared to modified Veau-Wardill-Kilner push-back at the age of three., (Copyright © 2022 Elsevier B.V. All rights reserved.)

Background and Purpose: Enterovirus infections pose a serious threat for patients with humoral deficiencies and may be lethal, whilst the efficacy of proposed treatment options such as corticosteroids, intravenous immunoglobulins and fluoxetine remains debated., Methods: Viral clearance was investigated in a patient with rituximab-induced B-cell depletion and chronic echovirus 13 (E13) meningoencephalitis/myofasciitis in response to intravenous immunoglobulins and fluoxetine using sequential semi-quantitative E13 viral load measurements by real-time reverse transcription polymerase chain reaction. Fluoxetine concentrations in plasma and cerebrospinal fluid were determined by liquid chromatography mass spectrometry., Results: Intravenous immunoglobulins appeared ineffective in this case of E13 infection, whereas virus clearance in cerebrospinal fluid was obtained after 167 days of oral fluoxetine. Since treatment with corticosteroids resulted in a flare of symptoms, rechallenge with viral load measurements was not attempted., Conclusion: In this report of a patient with rituximab-associated chronic echovirus 13 meningoencephalitis, viral clearance in response to single treatment options is assessed for the first time. Our observations further support the in vivo efficacy of fluoxetine against enteroviral infections. More research is needed to establish its efficacy in different enterovirus strains., (© 2022 European Academy of Neurology.)

Aims and Hypotheses: In an environment of absolute silence, researchers have found many of their participants to perceive phantom sounds (tinnitus). With this between-subject experiment, we aimed to elaborate on these research findings, and specifically investigated whether-in line with the fear-avoidance model of tinnitus perception and reactivity-fear or level of perceived threat influences the incidence and perceptual qualities of phantom sound percepts in an anechoic room. We investigated the potential role of individual differences in anxiety, negative affect, noise sensitivity and subclinical hearing loss. We hypothesized that participants who experience a higher level of threat would direct their attention more to the auditory system, leading to the perception of tinnitus-like sounds, which would otherwise be subaudible, and that under conditions of increased threat, narrowing of attention would lead to perceptual distortions., Methods: In total, N  = 78 normal-hearing volunteers participated in this study. In general, the study sample consisted of young, mostly female, university students. Their hearing was evaluated using gold-standard pure tone audiometry and a speech-in-noise self-test (Digit Triplet Test), which is a sensitive screening test to identify subclinical hearing loss. Prior to a four-minute stay in an anechoic room, we randomized participants block design-wise in a threat ( N  = 37) and no-threat condition ( N  = 41). Participants in the threat condition were deceived about their hearing and were led to believe that staying in the room would potentially harm their hearing temporarily. Participants were asked whether they perceived sounds during their stay in the room and rated the perceptual qualities of sound percepts (loudness and unpleasantness). They were also asked to fill-out standardized questionnaires measuring anxiety (State-Trait Anxiety Inventory), affect (Positive and Negative Affect Schedule) and noise sensitivity (Weinstein Noise Sensitivity Scale). The internal consistency of the questionnaires used was verified in our study sample and ranged between α  = 0.61 and α  = 0.90., Results: In line with incidence rates reported in the literature, 74% of our participants reported having heard tinnitus-like sounds in the anechoic room. Speech-in-noise identification ability was comparable for both groups of participants. The experimental manipulation of threat was proven to be effective, as indicated by significantly higher scores on a Threat Manipulation Checklist among participants in the threat condition as compared to those in the no-threat condition ( p  < 0.01). Nevertheless, participants in the threat condition were as likely to report tinnitus percepts as participants in the no-threat condition ( p  = 1), and tinnitus percepts were not rated as being louder ( p  = 0.76) or more unpleasant ( p  = 0.64) as a function of level of threat. For participants who did experience tinnitus percepts, a higher level of threat was associated with a higher degree of experienced unpleasantness ( p  < 0.01). These associations were absent in those who did not experience tinnitus. Higher negative affect was only slightly associated with higher ratings of tinnitus unpleasantness ( p  < 0.01)., Conclusion: Whereas our threat manipulation was successful in elevating the level of fear, it did not contribute to a higher percentage of participants perceiving tinnitus-like sounds in the threat condition. However, higher levels of perceived threat were related to a higher degree of perceived tinnitus unpleasantness. The findings of our study are drawn from a rather homogenous participant pool in terms of age, gender, and educational background, challenging conclusions that are applicable for the general population. Participants generally obtained normophoric scores on independent variables of interest: they were low anxious, low noise-sensitive, and there was little evidence for the presence of subclinical hearing loss. Possibly, there was insufficient variation in scores to find effects., Competing Interests: TEF since 2019 has been employed by Medtronic, Maastricht in a function/role entirely unrelated to this study. At the time the study was conceptualised, data collected and the preliminary analysis conducted TEF declares there was no commercial or financial relationships that could be construed as a potential conflict of interest. The remaining authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2022 Denys, Cima, Fuller, Ceresa, Blockmans, Vlaeyen and Verhaert.)

Background: The generally accepted method to assess the functionality of novel bone conduction implants in a preclinical stage is to experimentally measure the vibratory response of the cochlear promontory. Yet, bone conduction of sound is a complex propagation phenomenon, depending on both frequency and amplitude, involving different conduction pathways., Objectives: The aim of this study is to validate the use of intracochlear sound pressure (ICP) as an objective indicator for perceived loudness for bone conduction stimulation. It is investigated whether a correlation exists between intracochlear sound pressure measurements in cadaveric temporal bones and clinically obtained results using the outcome of a loudness balancing experiment., Methods: Ten normal hearing subjects were asked to balance the perceived loudness between air conducted (AC) sound and bone conducted (BC) sound by changing the AC stimulus. Mean balanced thresholds were calculated and used as stimulation levels in a cadaver trial (N = 4) where intracochlear sound pressure was measured during AC and BC stimulation to assess the correlation with the measured clinical data. The intracochlear pressure was measured at the relatively low stimulation amplitude of 80 dBHL using a lock-in amplification technique., Results: Applying AC and BC stimulation at equal perceived loudness on cadaveric heads yield a similar differential intracochlear pressure, with differences between AC and BC falling within the range of variability of normal hearing test subjects., Conclusion: Comparing the perceived loudness at 80 dB HL for both AC and BC validates intracochlear pressure as an objective indicator of the cochlear drive. The measurement setup is more time-intensive than measuring the vibratory response of the cochlear promontory, yet it provides direct information on the level of the cochlear scalae., Competing Interests: Declaration of interest This work has been supported by Flanders Innovation and Entrepreneurship (IWT155047). TP is fully funded by Research Foundation Flanders (FWO 12Y6919N). GF, CB and JW are currently employees of Cochlear Ltd. GF is partly funded by Flanders Innovation and Entrepreneurship (HBC.2018.0184), NV has a senior clinical investigator fund of Research Foundation Flanders (FWO 1804816N)., (Copyright © 2022. Published by Elsevier B.V.)

Active transcutaneous bone conduction (BC) devices offer the benefit of improved power output compared to passive transcutaneous devices and remove the risk of skin infections that are more common in traditional percutaneous BC devices. Despite these advantages, more research is needed on implant location, device coupling, and their influence on device performance. This study is aimed at quantifying the extent to which certain parameters affect device output when using the Osia® system actuator. Parameters under study are (1) implant location, (2) comparison with the actuator of a state-of-the-art BC device, (3) bone undergrowth simulation, and (4) skull fixation. Five human cadaveric heads were implanted with the actuator at three different implant locations: (1) recommended, (2) posterior Osia® positions, and (3) standard Baha® position. At each location, the cochlear promontory velocity and the intracochlear pressure difference were measured. A percutaneous bone conduction actuator was used as a reference for the obtained measurements. Stimulation levels corresponded to a hearing level of 60 dB HL for frequencies between 250 and 6000 Hz. In addition, bone cement was used as a simulation for reactive bone growth. Results obtained in four heads indicate an improved power transmission of the transcutaneous actuator when implanted at the recommended position compared to the actuator of the percutaneous device on its respective recommended location when stimulating at an identical force level. A correlation was found between the promontory vibration and the actuator position, indicating that the same level of stimulation leads to higher promontory vibrations when the device is implanted closer to the ear canal. This is mainly reflected at frequencies higher than 1 kHz, where an increase was observed in both measurement modalities. At lower frequencies (<1 kHz), the power transmission is less influenced by the implant position and differences between the acquired responses are limited. In addition, when no rigid coupling to the skull is provided, power transfer losses of up to 30 dB can be expected., Competing Interests: CB was an independent researcher at the moment of the experiments and data analysis, but at the moment of manuscript preparation, CB has become an employee of Cochlear Ltd. GF and JW are employees of Cochlear Ltd., (Copyright © 2022 Guy Fierens et al.)

Cochlear implantation initiates an inflammatory cascade in which both acute insertion trauma and chronic foreign body reaction lead to intracochlear fibrosis and loss of residual hearing. Several strategies have been proposed to attenuate the local reactive process after implantation, including intracochlear drug delivery. The present study gives an overview of what is being investigated in the field of inner ear therapeutics and cochlear implant surgery. The aim is to evaluate its potential benefit in clinical practice. A systematic search was conducted in PubMed, Embase, and Cochrane Library databases identifying comparative prospective studies examining the effect of direct inner ear drug application on mechanical cochlear trauma. Both animal and human studies were considered and all studies were assessed for quality according to the validated risk of bias tools. Intracochlear administration of drugs is a feasible method to reduce the local inflammatory reaction following cochlear implantation. In animal studies, corticosteroid use had a significant effect on outcome measures including auditory brainstem response, impedance, and histological changes. This effect was, however, only durable with prolonged drug delivery. Significant differences in outcome were predominantly seen in studies where the cochlear damage was extensive. Six additional reports assessing non-steroidal agents were found. Overall, evidence of anti-inflammatory effects in humans is still scarce.

Background: Tinnitus represents a relatively common condition in the global population accompanied by various comorbidities and severe burden in many cases. Nevertheless, there is currently no general treatment or cure, presumable due to the heterogeneity of tinnitus with its wide variety of etiologies and tinnitus phenotypes. Hence, most treatment studies merely demonstrated improvement in a subgroup of tinnitus patients. The majority of studies are characterized by small sample sizes, unstandardized treatments and assessments, or applications of interventions targeting only a single organ level. Combinatory treatment approaches, potentially targeting multiple systems as well as treatment personalization, might provide remedy and enhance treatment responses. The aim of the present study is to systematically examine established tinnitus therapies both alone and in combination in a large sample of tinnitus patients. Further, it wants to provide the basis for personalized treatment approaches by evaluating a specific decision support system developed as part of an EU-funded collaborative project (Unification of treatments and interventions for tinnitus patients; UNITI project)., Methods/study Design: This is a multi-center parallel-arm randomized clinical trial conducted at five different clinical sites over the EU. The effect of four different tinnitus therapy approaches (sound therapy, structured counseling, hearing aids, cognitive behavioral therapy) applied over a time period of 12 weeks as a single or rather a combinatory treatment in a total number of 500 chronic tinnitus patients will be investigated. Assessments and interventions are harmonized over the involved clinical sites. The primary outcome measure focuses on the domain tinnitus distress assessed via the Tinnitus Handicap Inventory., Discussion: Results and conclusions from the current study might not only provide an essential contribution to combinatory and personalized treatment approaches in tinnitus but could also provide more profound insights in the heterogeneity of tinnitus, representing an important step towards a cure for tinnitus., Trial Registration: ClinicalTrials.gov NCT04663828 . Registered on 11 December 2020., (© 2021. The Author(s).)

Making use of magnetic resonance imaging (MRI) for diagnostics on patients with implanted medical devices requires caution due to mutual interactions between the device and the electromagnetic fields used by the scanner that can cause a number of adverse events. The presented study offers a novel test method to quantify the risk of unintended output of acoustically stimulating hearing implants. The design and operating principle of an all-optical, MRI safe vibrometer is outlined, followed by an experimental verification of a prototype. Results obtained in an MRI environment indicate that the system can detect peak displacements down to 8 pm for audible frequencies. Feasibility testing was performed with an active middle ear implant that was exposed to several pulse sequences in a 1.5 Tesla MRI environment. Magnetic field induced actuator vibrations, measured during scanning, turned out to be equivalent to estimated sound pressure levels between 25 and 85 dB SPL, depending on the signal frequency. These sound pressure levels are situated well below ambient sound pressure levels generated by the MRI scanning process. The presented case study therefore indicates a limited risk of audible unintended output for the examined hearing implant during MRI.