Impact of unilateral vs. bilateral evaluation on cochlear implant candidacy.

BACKGROUND: The indication criteria for cochlear implantation differ considerably across regions. OBJECTIVES: To estimate the effects of different candidacy criteria on the number of cochlear implant (CI) candidates. METHODS: We analysed a very large clinical audiological database comprising pure-tone thresholds and speech-audiometric data in order to identify CI candidates on the basis of different audiometric candidacy criteria. In particular, we simulated the effects of three different CI candidacy criteria. RESULTS: The bilateral evaluation of CI candidacy has the strongest influence on the number of potential CI candidates. Additionally, the cut-off criteria for middle-ear implants have a large effect on numbers of candidates when air conduction has deteriorated.Conclusions and Significance: Expanding the indication criteria opens up the possibility of improving the accurate identification of individual cases suitable for cochlear-implant provision.

Associations between illness perceptions, word recognition, and perceived sound quality in cochlear implant users.

OBJECTIVE: Illness perceptions refer to thoughts and ideas an individual has about an illness. The aim was to understand how cochlear implant (CI) users' illness perceptions, in addition to their monosyllabic word recognition abilities, are associated with their self-perceived sound quality. DESIGN: Data were collected during routine CI check-up appointments. Participants completed the Brief Illness Perception Questionnaire (assessing their illness perceptions) and the Hearing Implant Sound Quality Index (assessing their subjective sound quality). Additionally, monosyllabic word recognition abilities were measured with the Freiburg Monosyllable Word Test. Hierarchical regression analysis were utilised to model users' sound quality ratings. Participants' age was entered first as a control variable. In the next step, monosyllabic word recognition was entered. Finally, participants' illness perceptions were entered. STUDY SAMPLE: Fifty-five participants with unilateral CI provision. RESULTS: Monosyllabic word recognition was significant in the second step. When illness perceptions and monosyllabic word recognition were both included in the third step, illness perceptions, but not monosyllabic word recognition, were significant. The model explained 22% of the variance of subjective sound quality. CONCLUSIONS: Monosyllabic word recognition abilities and illness perceptions of CI users are important for their self-reported sound quality, but illness perceptions appear to be potentially more relevant.

Electrically evoked compound action potentials in cochlear implant users with preoperative residual hearing.

Introduction: Residual hearing in cochlear implant (CI) candidates requires the functional integrity of the nerve in particular regions of the cochlea. Nerve activity can be elicited as electrically evoked compound action potentials (ECAP) after cochlear implantation. We hypothesize that ECAP thresholds depend on preoperative residual hearing ability. Materials and methods: In a retrospective study, we analyzed 84 adult cochlear implant users who had received a Nucleus® CI632 Slim Modiolar Electrode and who preoperatively had had residual hearing. Inclusion criteria were severe to profound hearing loss with preoperative measurable hearing in the ear to receive the implant, postlingual hearing loss, German as native language and correct placement of the electrode, inserted completely into the scala tympani. Electrically evoked compound action potential (ECAP) was recorded intraoperatively. The angular insertion was measured for each electrode contact from postoperative computed tomography to estimate the corresponding spiral ganglion frequency. Pure-tone audiometry and allocated ECAP thresholds were tested to investigate possible correlation. Results: The average of hearing thresholds, tested at 0.5, 1, 2, and 4 kHz (4FPTA) was 82 ± 18 (range 47-129) dB HL. The success rate for recording ECAP thresholds was 96.9%. For all comparable pure-tone frequencies (1, 2, 4, and 8 kHz), there was significant correlation between preoperative hearing levels and intraoperative ECAP thresholds (p < 0.001). Higher hearing thresholds are associated with increased ECAP thresholds. Conclusion: In CI candidates with adequate residual hearing, intraoperative electrophysiological measurement records lower thresholds. This outcome may be explained by the neural survival density of the peripheral system, with less neural degeneration.

Evolving a Model for Cochlear Implant Outcome.

BACKGROUND: Cochlear implantation is an efficient treatment for postlingually deafened adults who do not benefit sufficiently from acoustic amplification. Implantation is indicated when it can be foreseen that speech recognition with a cochlear implant (CI) is superior to that with a hearing aid. Especially for subjects with residual speech recognition, it is desirable to predict CI outcome on the basis of preoperative audiological tests. PURPOSE: The purpose of the study was to extend and refine a previously developed model for CI outcome prediction for subjects with preoperative word recognition to include subjects with no residual hearing by incorporating additional results of routine examinations. RESULTS: By introducing the duration of unaided hearing loss (DuHL), the median absolute error (MAE) of the prediction was reduced. While for subjects with preoperative speech recognition, the model modification did not change the MAE, for subjects with no residual speech recognition before surgery, the MAE decreased from 23.7% with the previous model to 17.2% with the extended model. CONCLUSIONS: Prediction of word recognition with CI is possible within clinically relevant limits. Outcome prediction is particularly important for preoperative counseling and in CI aftercare to support systematic monitoring of CI fitting.

Surgical Versus Noninvasive Manual Repositioning After Cochlear Implant Partial Magnet Dislocation.

Objectives: To compare surgical magnet repositioning (SMR) and noninvasive manual magnet repositioning (MMR) as treatments for partial magnet dislocation (PMD) of the internal magnet in a cochlear implant (CI) caused by magnetic resonance imaging (MRI). The primary objective was the success rate, while the secondary objectives were total postinterventional CI downtime and complications. Methods: This single-center retrospective study was conducted at a tertiary referral medical center. Patients with CI treated for PMD between January 1, 2007 and September 30, 2022 were included. SMR served as primary treatment until June 2019 and as secondary treatment after the introduction of MMR. Results: A total of 51 cases of PMD were observed in 42 patients and 43 devices (18 ♀; 24 ♂; 12 with bilateral CI). MMR was performed successfully in 19 out of 20 cases (95%), while 32 cases were managed successfully by SMR. The median age at first magnet repositioning was 53.8 years (minimum 19 years, maximum 93 years). When MMR was performed, the mean time from diagnosis to treatment (0.5 ± 1.5 days vs 9.8 ± 7.6 days; P < .01), the mean time from repositioning to CI reactivation (1.4 ± 4.3 days vs 13.1 ± 6.7 days; P < .01), and the mean total CI downtime (1.9 ± 4.8 days vs 22.9 ± 11.9 days; P < .01) were significantly shorter compared to SMR. Significantly fewer complications were experienced with MMR [n = 0 (0%) vs n = 8 (25%); P = .04]. Conclusion: In case of PMD caused by MRI, noninvasive MMR shows a high success rate with a shorter total CI downtime as well as a lower complication rate compared to SMR. Therefore, MMR should be considered as first line treatment with SMR as a second option in case of failure.

Validation of a predictive model for speech discrimination after cochlear impIant provision.

BACKGROUND: If sufficient speech discrimination is no longer achieved with conventional hearing systems, an audiological indication for a cochlear implant (CI) is given. However, there are no established target criteria for CI aftercare with regard to the level of speech comprehension to be achieved. The aim of this study is to validate an existing predictive model for speech comprehension after CI provision. This is applied to different patient groups. MATERIALS AND METHODS: The prospective study included 124 postlingually deaf adults. The model is based on preoperative maximum monosyllabic recognition score, aided monosyllabic recognition score at 65 dBSPL, and age the time of implantation. The model was investigated with regard to prediction accuracy for monosyllabic recognition with CI after 6 months. RESULTS: Mean speech discrimination improved from 10% with hearing aid to 65% with CI after 6 months, with a statistically significant improvement in 93% of cases. Deterioration of aided unilateral speech discrimination was not observed. The mean prediction error was 11.5 percentage points in the cases with preoperative scores better than zero and 23.2 percentage points in all other cases. CONCLUSION: Cochlear implantation should also be considered in patients with moderately severe to severe hearing loss and insufficient speech discrimination with hearing aids. The model based on preoperatively measured data for predicting speech discrimination with CI can be used in preoperative consultation and in the context of postoperative quality assurance.

Risk of magnetic resonance imaging-induced magnet dislocation for different types of cochlear implants: a single-center retrospective study.

BACKGROUND: When performing magnetic resonance imaging (MRI) in patients with a cochlear implant (CI), complication rates vary widely in the literature. The primary objective of this retrospective study was to determine the prevalence of complications, in particular magnet dislocation, in patients with CI undergoing 1.5 Tesla (T) MRI. As a secondary objective, the prevalence of magnet dislocation for specific cochlear implant device types was elaborated. METHODS: In a single-center retrospective study, all patients with a cochlear implant presenting for an MRI examination at 1.5 T at our institution between January 1st, 2010 and December 31st, 2020 were included. Implants with axial and diametrical magnets were included in the study. MRI safety measures were applied before imaging. The prevalence of complications was evaluated. Magnet dislocation rates were calculated for device types with at least 20 MRI exposures. RESULTS: During the study period, 196 MRI examinations were performed in a total of 128 patients, accounting for 149 different implants (21 implanted bilaterally) with a total of 231 implant exposures to MRI (average 1.69 ± 1.57; min. 1, max. 12). Complications were reported in 50 out of 231 cochlear implant exposures (21.6%). Magnet dislocation occurred in a total of 27 cases (11.7%). Dislocation rates were 29.6% for the Cochlear® CI500 series (24 dislocations from 81 exposures), 1.1% for the Cochlear® CI24RE series (1 from 87) and 0% for the MED-EL® Synchrony (0 from 36). The dislocation rate for the CI500 was significantly higher than for the CI24RE (χ2(1) = 26.86; p < 0.001; ϕ = 0.40) or the Synchrony (χ2(1) = 13.42; p < 0.001; ϕ = 0.34). CONCLUSIONS: For 1.5 T MRI, the risk of magnet dislocation ranges from 0 to 29.6% and depends on the CI device type. Implants with a diametrical magnet can be considered potentially MRI-safe, whereas in CIs with axial magnets, the CI500 is at high risk of magnet dislocation. Therefore, apart from a strict indication for an MRI and adherence to safety protocols, post-MRI follow-up examination to rule out magnet dislocation is recommended.

[Validation of a predictive model for speech discrimination after cochlear implant provision]. / Validierung eines Modells zur Vorhersage des Sprachverstehens nach Cochleaimplantation.

BACKGROUND: If sufficient speech discrimination is no longer achieved with conventional hearing systems, an audiological indication for a cochlear implant (CI) is given. However, there are no established target criteria for CI aftercare with regard to the level of speech comprehension to be achieved. The aim of this study is to validate an existing predictive model for speech comprehension after CI provision. This is applied to different patient groups. MATERIALS AND METHODS: The prospective study included 124 postlingually deaf adults. The model is based on preoperative maximum monosyllabic recognition score, aided monosyllabic recognition score at 65 dBSPL, and age the time of implantation. The model was investigated with regard to prediction accuracy for monosyllabic recognition with CI after 6 months. RESULTS: Mean speech discrimination improved from 10% with hearing aid to 65% with CI after 6 months, with a statistically significant improvement in 93% of cases. Deterioration of aided unilateral speech discrimination was not observed. The mean prediction error was 11.5 percentage points in the cases with preoperative scores better than zero and 23.2 percentage points in all other cases. CONCLUSION: Cochlear implantation should also be considered in patients with moderately severe to severe hearing loss and insufficient speech discrimination with hearing aids. The model based on preoperatively measured data for predicting speech discrimination with CI can be used in preoperative consultation and in the context of postoperative quality assurance.

Association between lateral wall electrode array insertion parameters and audiological outcomes in bilateral cochlear implantation.

PURPOSE: The aims of this study were to compare speech recognition at different postoperative times for both ears in bilaterally implanted patients and to assess the influence of the time of deafness, frequency-to-place mismatch, angular insertion depth (AID) and angular separation between neighbouring electrode contacts on audiometric outcomes. METHODS: This study was performed at an academic tertiary referral centre. A total of 19 adult patients (6 men, 13 women), who received sequential bilateral implantation with lateral wall electrode arrays, were analysed in retrospective. Statistical analysis was performed using two-sided t test, Wilcoxon test, median test, and Spearman's correlation. RESULTS: Postlingually deafened patients (deafness after the age of 10) had a significantly better speech perception (WRS65[CI]) than the perilingually deafened subjects (deafness at the age of 1-10 years) (p < 0.001). Comparison of cochlear duct length between peri- and postlingually deafened subjects showed a slightly significantly smaller cochleae in perilingual patients (p = 0.045). No association between frequency-to-place mismatch as well as angular separation and speech perception could be detected. There was even no significant difference between the both ears in the intraindividual comparison, even if insertion parameters differed. CONCLUSION: The exact electrode position seems to have less influence on the speech comprehension of CI patients than already established parameters as preoperative speech recognition or duration of deafness.

Cochlear Implantation Following Explorative Tympanotomy in Patients With Sudden Sensorineural Hearing Loss: Surgical Features and Audiological Outcomes.

OBJECTIVE: To investigate the anatomical status of the round window niche and hearing outcome of cochlear implantation (CI) after explorative tympanotomy (ExT) with sealing of the round window membrane in patients with sudden sensorineural hearing loss at a tertiary referral medical center. METHODS: Between January 1, 2007, and July 30, 2020, 1602 patients underwent CI at our department. Out of these, all patients previously treated by ExT with sealing of the round window membrane because of unilateral sudden hearing loss were included in the study. A retrospective chart review was conducted concerning method of round window membrane sealing, intraoperative findings during CI, postoperative imaging, and hearing results. RESULTS: Twenty one patients (9 females; 8 right ears; 54.3 years [± 12.9 years]) underwent ExT with sealing of the round window membrane with subsequent CI after 26.6 months (± 32.9 mo) on average. During CI, in 76% of cases (n = 16), the round window niche was blocked by connective tissue due to the previous intervention but could be removed completely in all cases. The connective tissue itself and its removal had no detrimental effects on the round window membrane. Postoperative computed tomography scan showed no electrode dislocation. Mean postoperative word recognition score after 3 months was 57.4% (± 17.2%) and improved significantly to 73.1% (± 16.4%, P = .005) after 2 years. CONCLUSION: Performing CI after preceding ExT, connective tissue has to be expected blocking the round window niche. Remaining tissue can be removed safely and does not alter the round window membrane allowing for a proper electrode insertion. Short- and long-term hearing results are satisfactory. Consequently, ExT with sealing of the round window membrane in patients with sudden sensorineural hearing loss does not impede subsequent CI that can still be performed safely.

Children with cochlear implant and additional disabilities benefit from consistent device use.

OBJECTIVES: Although the prevalence of additional disabilities (AD) in children with a cochlear implant (CI) is high, children with such disabilities are often excluded from clinical studies, or their specific characteristics are only partially included. The literature shows that several factors need to be considered in evaluating auditory and language development in CI children with AD, including demographic variables as well as the severity and type of disability. Current findings on device use in children show correlations with auditory and language outcome, but little is known about device use specifically in children with AD. The purpose of this study was to determine the auditory and language outcome of CI children with AD and to analyse their datalogging-based daily device use, both 1 year and 2 years after implantation. In addition, any potential correlations between outcome and device use were to be identified. METHODS: A cohort of 32 CI children with 5 different types of AD were included in this retrospective analysis. The children's auditory and language outcome was assessed by the parental questionnaires LittlEARS and ELFRA and by the professional observation tool CAP (Categories of Auditory Performance) 1 and 2 years after implantation. Longitudinal device use was analysed by using the CI system-integrated data-logging; daily duration of CI use, number of coil disconnections and exposure to different listening scenes were recorded. RESULTS: Overall, the cohort's auditory and language performance showed significant progress over time, while reduced abilities became more obvious after 2 years of CI experience. The mean daily duration of CI use increased significantly from 7.8 ± 2.8 to 8.2 ± 2.7 h after 2 years. High numbers of daily coil disconnections were detected, with a significant mean decrease from 83.4 ± 73.1 to 66.3 ± 54.6 whereas the percentage exposure to different listening environments was widely stable over time. Significant rank correlations were identified between outcomes measured by ELFRA and CAP with daily duration of CI use, numbers of coil disconnections and percentage of exposure to speech-characterised listening scenes. CONCLUSION: The auditory and language outcome in CI children with AD is variable, but it progresses over time. Children benefit from a consistent daily device use as well as from a high exposure to speech-characterised environments. Device use should be monitored constantly, with particular focus on daily duration of CI use and, in particular, on the number of coil disconnections if children have a severe motor impairment. Objective data-logging is an important addition to outcome assessment by testing, observations and parental questionnaires. Although assessment in children with AD is a major challenge for professionals, comprehensive assessment is needed to improve cochlear implant services with special adaption to children with AD, and this should include audiological, development-related and psychosocial information. A unified system to classify types of disabilities could help to improve procedures for analysing different outcomes.

[Word production in children with cochlear implant based on chronological age and hearing age]. / Hör- und Lebensalter-bezogene Wortproduktion von Kindern mit Cochlea-Implantat.

BACKGROUND: For congenitally deaf children, an early bilateral provision with cochlear implant (CI) is a favourable condition for language acquisition. The objective of the present study was to determine the word production in CI children. The focus was on a comparison of chronological age and hearing age performance and on the evaluation of potential effects of multilingualism, additional disabilities and age at provision. METHODS: The data of 62 children with bilateral CI (age at provision in months M=12,1; SD=6,2) were retrospectively analysed. Vocabulary was assessed by the test Aktiver Wortschatztest für 3- bis 5-jährige Kinder - Revision and compared for chronological age and hearing age. Group comparisons and correlation analysis was conducted regarding multilingualism, additional disabilities and age at provision. RESULTS: The cohort performed significantly better when referenced to hearing age: level were within or above the norm in more than 50%; referenced to chronological age in around 37%. The descriptive performance differences for multilingualism and additional disabilities were only significant for children with both characteristics. Performance of monolingual children without additional disabilities was not significantly associated with age at provision. CONCLUSION: CI children may achieve an adequate expressive vocabulary at the age of 3 to 5 years. Multilingualism and additional disabilities seem to be particular challenges for CI children and need a more precise definition in further studies. The use of both chronological and hearing age as reference marks allows a differentiated assessment of the language status. This may lead to benefits in therapeutic interventions and parent councelling.

Age-Related Decline of Speech Perception.

Hearing loss is one of the most common disorders worldwide. It affects communicative abilities in all age groups. However, it is well known that elderly people suffer more frequently from hearing loss. Two different model approaches were employed: A generalised linear model and a random forest regression model were used to quantify the relationship between pure-tone hearing loss, age, and speech perception. Both models were applied to a large clinical data set of 19,801 ears, covering all degrees of hearing loss. They allow the estimation of age-related decline in speech recognition for different types of audiograms. Our results show that speech scores depend on the specific type of hearing loss and life decade. We found age effects for all degrees of hearing loss. A deterioration in speech recognition of up to 25 percentage points across the whole life span was observed for constant pure-tone thresholds. The largest decrease was 10 percentage points per life decade. This age-related decline in speech recognition cannot be explained by elevated hearing thresholds as measured by pure-tone audiometry.

Prediction of Speech Intelligibility by Means of EEG Responses to Sentences in Noise.

Objective: Understanding speech in noisy conditions is challenging even for people with mild hearing loss, and intelligibility for an individual person is usually evaluated by using several subjective test methods. In the last few years, a method has been developed to determine a temporal response function (TRF) between speech envelope and simultaneous electroencephalographic (EEG) measurements. By using this TRF it is possible to predict the EEG signal for any speech signal. Recent studies have suggested that the accuracy of this prediction varies with the level of noise added to the speech signal and can predict objectively the individual speech intelligibility. Here we assess the variations of the TRF itself when it is calculated for measurements with different signal-to-noise ratios and apply these variations to predict speech intelligibility. Methods: For 18 normal hearing subjects the individual threshold of 50% speech intelligibility was determined by using a speech in noise test. Additionally, subjects listened passively to speech material of the speech in noise test at different signal-to-noise ratios close to individual threshold of 50% speech intelligibility while an EEG was recorded. Afterwards the shape of TRFs for each signal-to-noise ratio and subject were compared with the derived intelligibility. Results: The strongest effect of variations in stimulus signal-to-noise ratio on the TRF shape occurred close to 100 ms after the stimulus presentation, and was located in the left central scalp region. The investigated variations in TRF morphology showed a strong correlation with speech intelligibility, and we were able to predict the individual threshold of 50% speech intelligibility with a mean deviation of less then 1.5 dB. Conclusion: The intelligibility of speech in noise can be predicted by analyzing the shape of the TRF derived from different stimulus signal-to-noise ratios. Because TRFs are interpretable, in a manner similar to auditory evoked potentials, this method offers new options for clinical diagnostics.

Evaluation of a Transimpedance Matrix Algorithm to Detect Anomalous Cochlear Implant Electrode Position.

INTRODUCTION: Transimpedance measurements from cochlear implant electrodes have the potential to identify anomalous electrode array placement, such as tip fold-over (TFO) or fold-back, basal electrode kinking, or buckling. Analysing transimpedance may thus replace intraoperative or post-operative radiological imaging to detect any potential misplacements. A transimpedance algorithm was previously developed to detect deviations from a normal electrode position with the aim of intraoperatively detecting TFO. The algorithm had been calibrated on 35 forced, tip folded electrode arrays in six temporal bones to determine the threshold criterion required to achieve a sensitivity of 100%. Our primary objective here was to estimate the specificity of this TFO algorithm in patients, in a prospective study, for a series of electrode arrays shown to be normally inserted by post-operative imaging. METHODS: Intracochlear voltages were intraoperatively recorded for 157 ears, using Cochlear's Custom Sound™ EP 5 electrophysiological software (Cochlear Ltd., Sydney, NSW, Australia), for both Nucleus® CI512 and CI532 electrode arrays. The algorithm analysed the recorded 22 × 22 transimpedance matrix (TIM) and results were displayed as a heatmap intraoperatively, only visible to the technician in the operating theatre. After all clinical data were collected, the algorithm was evaluated on the bench. The algorithm measures the transimpedance gradients and corresponding phase angles (θ) throughout the TIM and calculates the gradient phase range. If this was greater than the predetermined threshold, the algorithm classified the electrode array insertion as having a TFO. RESULTS: Five ears had no intraoperative TIM and four anomalous matrices were identified from heatmaps and removed from the specificity analysis. Using the 148 remaining data sets (n = 103 CI532 and n = 45 CI512), the algorithm had an average specificity of 98.6% (95.80%-99.75%). CONCLUSION: The algorithm was found to be an effective screening tool for the identification of TFOs. Its specificity was within acceptable levels and resulted in a positive predictive value of 76%, with an estimated incidence of fold-over of 4% in perimodiolar arrays. This would mean 3 out of 4 cases flagged as a fold-over would be correctly identified by the algorithm, with the other being a false positive. The measurements were applied easily in theatre allowing it to be used as a routine clinical tool for confirming correct electrode placement.

[Effectiveness of hearing aid provision for severe hearing loss]. / Wirksamkeit der Hörgeräteversorgung bei hochgradigem Hörverlust.

BACKGROUND AND OBJECTIVE: In practice, the unilateral monosyllabic speech recognition score with hearing aid (WRS65(HA)) is often below the maximum word recognition score with headphones (WRSmax), in particular for subjects with severe hearing loss. The aim of this study was to evaluate the efficiency factor Q of hearing aid provision, the ratio WRS65(HA)/WRSmax, in patients with severe to profound hearing loss. MATERIALS AND METHODS: Data from real-ear measurements (REM), pure tone and speech audiogram, and speech recognition with and without hearing aid of 93 ears in 64 patients were examined. The patients visited the authors' hearing center for hearing aid evaluation in 2019. Deviations of the real-ear measured frequency-dependent output level values from the prescription targets NAL-NL2 and DSL v5.0 were analyzed. Spearman correlation coefficients for the speech intelligibility index (SII) were calculated for the parameters WRS65(HA) and Q. RESULTS: In more than 67% of the hearing aid fittings, output level values matched the target curves of NAL-NL2 or DSL v5.0 in the range of ±5 dB for frequencies from 0.5 to 4 kHz at 65 dB SPL. Nevertheless, WRSmax was not achieved with hearing aid at conversational speech levels of 65 dB SPL (mean deviations: 34.4%). However, WRS65(HA) and Q were best when target values for DSL v5.0 were achieved at 65 dB SPL, which is associated with a higher SII. CONCLUSION: For patients with severe to profound hearing loss, the prescription targets of NAL-NL2 and DSL v5.0 do not provide sufficient amplification for WRSmax to be achieved at a normal speech level of 65 dB SPL. It remains to be investigated whether alternative prescriptions with better audibility for input levels of 50 and 65 dB SPL might improve the effectiveness of hearing aid provision.

Diagnosing complications following cochlear implantation using transcutaneous ultrasound.

PURPOSE: The aim of this study was to investigate the feasibility and reliability of transcutaneous ultrasound for the detection of complications after cochlear implantation. METHODS: In a single center retrospective cohort study, 115 consecutive cases of suspected complications after cochlear implantation (intervention group) were examined. The rate of pathologic ultrasound findings for specific leading symptoms and diagnoses was compared to a control group comprising twenty consecutive cochlear implants in symptom-free patients. RESULTS: Diagnostic ultrasound showed distinctly more pathologic findings in the intervention group (n = 67; 58.3%; p < 0.001) compared to the control group (n = 1; 5%). Ultrasound revealed significantly more pathologic findings in haematoma or seroma around the implant (n = 17; 100%; p < 0.001; ϕ = 0.94) and magnet dislocation (n = 44; 97.7%; p < 0.001; ϕ = 0.92) confirmed by a strong effect. Ultrasound examination showed a medium to high effect size in patients presenting with local infections (n = 3; 21.4%; p = 0.283; ϕ = 0.25) and skin flap oedema (n = 2; 50%; p = 0.061; ϕ = 0.51). In contrast, ultrasound examinations displayed a low effect size in undefined cephalgia (0%; p = 0.444; ϕ = 0.17) and device malfunction or failure (0%; p > 0.999; ϕ = 0.13). CONCLUSION: Transcutaneous ultrasound can be advocated as a feasible and effective method in the diagnostic work-up of magnet dislocation and haematoma or seroma around the implant following cochlear implantation. Contrary, ultrasound findings can be expected to be inconspicuous in patients presenting with undefined cephalgia and device malfunction or failure.

Challenging social media threats using collective well-being-aware recommendation algorithms and an educational virtual companion.

Social media have become an integral part of our lives, expanding our interlinking capabilities to new levels. There is plenty to be said about their positive effects. On the other hand, however, some serious negative implications of social media have been repeatedly highlighted in recent years, pointing at various threats to society and its more vulnerable members, such as teenagers, in particular, ranging from much-discussed problems such as digital addiction and polarization to manipulative influences of algorithms and further to more teenager-specific issues (e.g., body stereotyping). The impact of social media-both at an individual and societal level-is characterized by the complex interplay between the users' interactions and the intelligent components of the platform. Thus, users' understanding of social media mechanisms plays a determinant role. We thus propose a theoretical framework based on an adaptive "Social Media Virtual Companion" for educating and supporting an entire community, teenage students, to interact in social media environments in order to achieve desirable conditions, defined in terms of a community-specific and participatory designed measure of Collective Well-Being (CWB). This Companion combines automatic processing with expert intervention and guidance. The virtual Companion will be powered by a Recommender System (CWB-RS) that will optimize a CWB metric instead of engagement or platform profit, which currently largely drives recommender systems thereby disregarding any societal collateral effect. CWB-RS will optimize CWB both in the short term by balancing the level of social media threats the users are exposed to, and in the long term by adopting an Intelligent Tutor System role and enabling adaptive and personalized sequencing of playful learning activities. We put an emphasis on experts and educators in the educationally managed social media community of the Companion. They play five key roles: (a) use the Companion in classroom-based educational activities; (b) guide the definition of the CWB; (c) provide a hierarchical structure of learning strategies, objectives and activities that will support and contain the adaptive sequencing algorithms of the CWB-RS based on hierarchical reinforcement learning; (d) act as moderators of direct conflicts between the members of the community; and, finally, (e) monitor and address ethical and educational issues that are beyond the intelligent agent's competence and control. This framework offers a possible approach to understanding how to design social media systems and embedded educational interventions that favor a more healthy and positive society. Preliminary results on the performance of the Companion's components and studies of the educational and psychological underlying principles are presented.