Auditory cortical plasticity after cochlear implantation in asymmetric hearing loss is related to spatial hearing: a PET H215O study.

In asymmetric hearing loss (AHL), the normal pattern of contralateral hemispheric dominance for monaural stimulation is modified, with a shift towards the hemisphere ipsilateral to the better ear. The extent of this shift has been shown to relate to sound localization deficits. In this study, we examined whether cochlear implantation to treat postlingual AHL can restore the normal functional pattern of auditory cortical activity and whether this relates to improved sound localization. The auditory cortical activity was found to be lower in the AHL cochlear implanted (AHL-CI) participants. A cortical asymmetry index was calculated and showed that a normal contralateral dominance was restored in the AHL-CI patients for the nonimplanted ear, but not for the ear with the cochlear implant. It was found that the contralateral dominance for the nonimplanted ear strongly correlated with sound localization performance (rho = 0.8, P < 0.05). We conclude that the reorganization of binaural mechanisms in AHL-CI subjects reverses the abnormal lateralization pattern induced by the deafness, and that this leads to improved spatial hearing. Our results suggest that cochlear implantation enables the reconstruction of the cortical mechanisms of spatial selectivity needed for sound localization.

Ultrarare heterozygous pathogenic variants of genes causing dominant forms of early-onset deafness underlie severe presbycusis.

Presbycusis, or age-related hearing loss (ARHL), is a major public health issue. About half the phenotypic variance has been attributed to genetic factors. Here, we assessed the contribution to presbycusis of ultrarare pathogenic variants, considered indicative of Mendelian forms. We focused on severe presbycusis without environmental or comorbidity risk factors and studied multiplex family age-related hearing loss (mARHL) and simplex/sporadic age-related hearing loss (sARHL) cases and controls with normal hearing by whole-exome sequencing. Ultrarare variants (allele frequency [AF] < 0.0001) of 35 genes responsible for autosomal dominant early-onset forms of deafness, predicted to be pathogenic, were detected in 25.7% of mARHL and 22.7% of sARHL cases vs. 7.5% of controls (P = 0.001); half were previously unknown (AF < 0.000002). MYO6, MYO7A, PTPRQ, and TECTA variants were present in 8.9% of ARHL cases but less than 1% of controls. Evidence for a causal role of variants in presbycusis was provided by pathogenicity prediction programs, documented haploinsufficiency, three-dimensional structure/function analyses, cell biology experiments, and reported early effects. We also established Tmc1N321I/+ mice, carrying the TMC1:p.(Asn327Ile) variant detected in an mARHL case, as a mouse model for a monogenic form of presbycusis. Deafness gene variants can thus result in a continuum of auditory phenotypes. Our findings demonstrate that the genetics of presbycusis is shaped by not only well-studied polygenic risk factors of small effect size revealed by common variants but also, ultrarare variants likely resulting in monogenic forms, thereby paving the way for treatment with emerging inner ear gene therapy.

Evolution in the management of vestibular schwannoma: a single-center 15-year experience.

PURPOSE: To highlight the changes in the management of vestibular schwannoma (VS) since 2004 with a focus on small- to middle-size VS. METHODS: Retrospective analysis of the decisions made in skull base tumor board between 2004 and 2021. RESULTS: 1819 decisions were analyzed (average age 59.25, 54% females). Overall, 850 (47%) cases were allocated to a Wait and Scan (WS) approach, 416 (23%) received radiotherapy and 553 (30%) were treated surgically (MS). All stages considered WS increased from 39% before 2010 to 50% after 2010. Similarly, Stereotactic Radio Therapy (SRT) increased from 5 to 18%. MS decreased from 46 to 25%. It was more commonly proposed to younger patients and larger tumors, p < 0.001. For Koos stages 1, 2, and 3 there was a statistically significant increase in SRT, and a decrease in MS, p < 0.001. WS also increased for stages 1 and 2. However, such a trend was not observed for stage 3. MS remained the primary treatment modality for stage 4 tumors throughout the study period, p = 0.057. The significance of advanced age as a factor favoring SRT decreased over time. The opposite is true for serviceable hearing. There was also a decrease in the percentage of the justification "young age" in the MS category. CONCLUSION: The is a continuing trend towards non-surgical treatment. Small- to medium-sized VS witnessed an increase in both WS and SRT. There is only an increase in SRT for moderately large VS. Physicians are less and less considering young age as a factor favoring MS over SRT. There is a tendency towards favoring SRT when hearing is serviceable.

Intensity patterns at the peaks of brain activity in fMRI and PET are highly correlated with neural models of spatial integration.

Spatial integration during the brain's cognitive activity prompts changes in energy used by different neuroglial populations. Nevertheless, the organisation of such integration in 3D -brain activity remains undescribed from a quantitative standpoint. In response, we applied a cross-correlation between brain activity and integrative models, which yielded a deeper understanding of information integration in functional brain mapping. We analysed four datasets obtained via fundamentally different neuroimaging techniques (functional magnetic resonance imaging [fMRI] and positron emission tomography [PET]) and found that models of spatial integration with an increasing input to each step of integration were significantly more correlated with brain activity than models with a constant input to each step of integration. In addition, marking the voxels with the maximal correlation, we found exceptionally high intersubject consistency with the initial brain activity at the peaks. Our method demonstrated for the first time that the network of peaks of brain activity is organised strictly according to the models of spatial integration independent of neuroimaging techniques. The highest correlation with models integrating an increasing at each step input suggests that brain activity reflects a network of integrative processes where the results of integration in some neuroglial populations serve as an input to other neuroglial populations.

Cochlear Implantation and Other Treatments in Single-Sided Deafness and Asymmetric Hearing Loss: Results of a National Multicenter Study Including a Randomized Controlled Trial.

INTRODUCTION: Cochlear implantation is a recent approach proposed to treat single-sided deafness (SSD) and asymmetric hearing loss (AHL). Several cohort studies showed its effectiveness on tinnitus and variable results on binaural hearing. The main objective of this study is to assess the outcomes of cochlear implantation and other treatment options in SSD/AHL on quality of life. METHODS: This prospective multicenter study was conducted in 7 tertiary university hospitals and included an observational cohort study of SSD/AHL adult patients treated using contralateral routing of the signal (CROS) hearing aids or bone-anchored hearing systems (BAHSs) or who declined all treatments, and a randomized controlled trial in subjects treated by cochlear implantation, after failure of CROS and BAHS trials. In total, 155 subjects with SSD or AHL, with or without associated tinnitus, were enrolled. After 2 consecutive trials with CROS hearing aids and BAHSs on headband, all subjects chose any of the 4 treatment options (abstention, CROS, BAHS, or cochlear implant [CI]). The subjects who opted for a CI were randomized between 2 arms (CI vs. initial observation). Six months after the treatment choice, quality of life was assessed using both generic (EuroQoL-5D, EQ-5D) and auditory-specific quality-of-life indices (Nijmegen Cochlear implant Questionnaire [NCIQ] and Visual Analogue Scale [VAS] for tinnitus severity). Performances for speech-in-noise recognition and localization were measured as secondary outcomes. RESULTS: CROS was chosen by 75 subjects, while 51 opted for cochlear implantation, 18 for BAHSs, and 11 for abstention. Six months after treatment, both EQ-5D VAS and auditory-specific quality-of-life indices were significantly better in the "CI" arm versus "observation" arm. The mean effect of the CI was particularly significant in subjects with associated severe tinnitus (mean improvement of 20.7 points ± 19.7 on EQ-5D VAS, 20.4 ± 12.4 on NCIQ, and 51.4 ± 35.4 on tinnitus). No significant effect of the CI was found on binaural hearing results. Before/after comparisons showed that the CROS and BAHS also improved significantly NCIQ scores (for CROS: +7.7, 95% confidence interval [95% CI] = [4.5; 10.8]; for the BAHS: +14.3, 95% CI = [7.9; 20.7]). CONCLUSION: Cochlear implantation leads to significant improvements in quality of life in SSD and AHL patients, particularly in subjects with associated severe tinnitus, who are thereby the best candidates to an extension of CI indications.

Treatment choice in single-sided deafness and asymmetric hearing loss. A prospective, multicentre cohort study on 155 patients.

OBJECTIVES: To describe the treatment choice in a cohort of subjects with single-sided deafness (SSD) and asymmetric hearing loss (AHL). To assess the reliability of the treatment trials. DESIGN: In this national, multicentre, prospective study, the choice of subjects was made after two consecutive trials of Contralateral Routing Of the Signal (CROS) hearing aids and a Bone Conduction Device (BCD) on a headband. Subjects could proceed with one of these two options, opt for cochlear implantation or decline all treatments. SETTING: Seven tertiary university hospitals. PARTICIPANTS: One hundred fifty-five subjects with SSD or AHL fulfilling the candidacy criteria for cochlear implantation, with or without associated tinnitus. MAIN OUTCOME MEASURES: After the two trials, the number of subjects choosing each option was described. Repeated assessments of both generic and auditory-specific quality of life were conducted, as well as hearing assessments (speech recognition in noise and horizontal localization). RESULTS: CROS was chosen by 75 subjects, followed by cochlear implantation (n = 51), BCD (n = 18) and abstention (n = 11). Patients who opted for cochlear implantation had a poorer quality of life (P = .03). The improvement of quality of life indices after each trial was significantly associated with the final treatment choice (P = .008 for generic indices, P = .002 for auditory-specific indices). The follow-up showed that this improvement had been overestimated in the CROS group, with a long-term retention rate of 52.5%. CONCLUSIONS: More than one third of SSD/AHL subjects are unsatisfied after CROS and BCD trials. Repeated quality of life assessments help counselling the patient for his/her treatment choice.

Stimulus-specific information is represented as local activity patterns across the brain.

Modern neuroimaging represents three-dimensional brain activity, which varies across brain regions. It remains unknown whether activity of different brain regions has similar spatial organization to reflect similar cognitive processes. We developed a rotational cross-correlation method allowing a straightforward analysis of spatial activity patterns distributed across the brain in stimulation specific contrast images. Results of this method were verified using several statistical approaches on real and simulated random datasets. We found, for example, that the seed patterns in the fusiform face area were robustly correlated to brain regions involved in face-specific representations. These regions differed from the non-specific visual network meaning that activity structure in the brain is locally preserved in stimulus-specific regions. Our findings indicate spatially correlated perceptual representations in cerebral activity and suggest that the 3D coding of the processed information is organized using locally preserved activity patterns across the brain. More generally, our results demonstrate that information is represented and shared in the local spatial configurations of brain activity.

Early Sentence Recognition in Adult Cochlear Implant Users.

OBJECTIVE: Normal-hearing subjects listening to acoustic simulations of cochlear implants (CI) can obtain sentence recognition scores near 100% in quiet and in 10 dB signal-to-noise ratio (SNR) noise with acute exposure. However, average sentence recognition scores for real CI listeners are generally lower, even after months of experience, and there is a high degree of heterogeneity. Our aim was to identify the relative importance and strength of factors that prevent CI listeners from achieving early, 1-mo scores as high as those for normal-hearing-listener acoustic simulations. DESIGN: Sentence recognition scores (100 words/list, 65 dB SPL) using CI alone were collected for all adult unilateral CI listeners implanted in our center over a 5-yr period. Sentence recognition scores in quiet and in 10 dB SNR 8-talker babble, collected from 1 to 12 mo, were reduced to a single dependent variable, the "initial" score, via logarithmic regression. "Initial" scores equated to an improved estimate of 1-mo scores, and integrated the time to rise above zero score for poorer performing subjects. Demographic, device, and medical data were collected for 118 subjects who met standard CI candidacy criteria. Computed tomography of the electrode array allowing determination of the insertion depth as an angle, and the presence or absence of scala dislocation was available for 96 subjects. Predictive factors for initial scores were selected using stepwise multiple linear regression. The relative importance of predictive factors was estimated as partial r with a low bias method, and statistical significance tested with type II analysis of variance. RESULTS: The etiologies chronic otitis and autoimmune disease were associated with lower, widely variable sentence recognition scores in the long-term. More than 60% of CI listeners scored >50/100 in quiet at 1 mo. Congenital hearing loss was associated with significantly lower initial scores in quiet (r 0.23, p < 0.001), as was longer duration of hearing loss (r 0.12, p < 0.001, -0.76 pts per year). Initial scores were negatively correlated with insertion depth (r 0.09, p < 0.001, -0.1 pts per degree), with the highest initial scores being obtained for insertion depths of 300° to 400°. A much greater proportion of scala dislocations was found for perimodiolar arrays compared with straight arrays. Scores were negatively correlated with the proportion of the active electrode array found in scala vestibuli for Nucleus perimodiolar devices (r 0.14, p < 0.01, coefficient -25). Similar overall results were obtained for sentence recognition scores in noise (+10 dB SNR). The intercept value for the obtained regression functions indicated that CI listeners with the least limiting factors generally scored ~95/100 in quiet and ~90/100 in noise. In addition, CI listeners with insertion angles as low as 315° to 360° could obtain sentence recognition scores >80/100 even at 1 day after activation. Insertion depths of 360° were estimated to produce frequency-place mismatches of about one octave upward shift. CONCLUSIONS: Patient-related factors etiology and duration of deafness together explained ~40% of the variance in early sentence recognition scores, and electrode position factors ~20%. CI listeners with insertion depths of about one turn obtained the highest early sentence recognition scores in quiet and in noise, and these were comparable with those reported in the literature for normal-hearing subjects listening to 8 to 12 channel vocoder simulations. Differences between device brands were largely explained by differences in insertion depths. This indicates that physiological frequency-place mismatches of about one octave are rapidly accommodated by CI users for understanding sentences, between 1 day to 1 mo postactivation, and that channel efficiency may be significantly poorer for more deeply positioned electrode contacts.

Cochlear implantation as a treatment for single-sided deafness and asymmetric hearing loss: a randomized controlled evaluation of cost-utility.

BACKGROUND: Single-sided deafness (SSD) and asymmetric hearing loss (AHL) have recently been proposed as a new indication for cochlear implantation. There is still no recommended treatment for these hearing deficits, and most options considered rely on the transfer of sound from the poor ear to the better ear, using Contralateral Routing of the Signal (CROS) hearing aids or bone conduction (BC) devices. In contrast, cochlear implantation allows the poor ear to be stimulated and binaural hearing abilities to be partially restored. Indeed, most recently published studies have reported an improvement in the spatial localisation of an incoming sound and better speech recognition in noisy environments after cochlear implantation in SSD/AHL subjects. It also provides consistent relief of tinnitus when associated. These encouraging hearing outcomes raise the question of the cost-utility of this expensive treatment in an extended indication. METHODS: The final endpoint of this national multicentre study is to determine the incremental cost-utility ratio (ICUR) of cochlear implantation in comparison to the current standard of care in France through simple observation, using a randomised controlled trial. Firstly, the study comprises a prospective and descriptive part, where 150 SSD/AHL subjects try CROS hearing aids and a BC device for three weeks each. Secondly, the choice is made between CROS hearing aids, BC implanted device and cochlear implantation. Hearing outcomes and quality of life measurements are described after 6 months for the subjects who chose CROS, BC or declined any option. The subjects who opt for cochlear implantation are randomised between one group where the cochlear implant is inserted without delay and one group of simple initial observation. Hearing outcomes and quality of life measurements are compared after 6 months. DISCUSSION: The present study was designed to assess the efficiency of cochlear implantation in SSD/AHL. A favourable cost-utility ratio in this extended indication would strengthen the promising clinical results and justify a reimbursement by the health insurance. The efficiency of other options (CROS, BC) will also be described. TRIAL REGISTRATION: This research has been registered in ClinicalTrials.gov (http://www.clinicaltrials.gov/), the 29th July 2014 under the n°NCT02204618.

Five-Year Hearing Outcomes in Bilateral Simultaneously Cochlear-Implanted Adult Patients.

OBJECTIVE: To report the speech performance and sound localization in adult patients 5 years after bilateral simultaneous cochlear implantation and to evaluate the change in speech scores between 1 and 5 years. DESIGN: In this prospective multicenter study, 26 patients were evaluated 5 years after implantation using long straight electrode arrays (MED-EL Combi 40+, standard electrode array, 31 mm). Speech perception was measured using disyllabic words in quiet and noise, with the speech coming from the front and a cocktail party background noise coming from 5 loudspeakers. Speech localization measurements were performed in noise under the same test conditions. These results were compared to those obtained at 1 year reported in a previous study. RESULTS: Five years after implantation, an improvement in speech performance scores compared to 1 year after implantation was found for the poorer ear both in quiet and in noise (+12.1 ± 2.6%, p < 0.001). The lower the speech score of the poorer ear at 1 year, the greater the improvement at 5 years, both in quiet (r = -0.62) and at a signal-to-noise ratio of +15 dB (r = -0.58). The sound localization on the horizontal plane in noise provided by bilateral implantation was better than the unilateral one and remained stable after the results observed at 1 year. CONCLUSION: In adult patients simultaneously and bilaterally implanted, the poorest speech scores improved between 1 and 5 years after implantation. These findings are an additional element to recommend bilateral implantation in adult patients. The use of both cochlear implants and speech training sessions for patients with poor performance should continue in the period after 1 year following implantation, since the speech scores will improve over time.

Quality of life and auditory performance in adults with asymmetric hearing loss.

We evaluated the relationship between binaural hearing deficits and quality of life. The study included 49 adults with asymmetric hearing loss (AHL), and 11 adult normal-hearing listeners (NHL) served as controls. Speech reception thresholds (SRT) were assessed with the French Matrix Test. Quality of life was evaluated with the Speech, Spatial and Qualities of Hearing Scale (SSQ) and the Glasgow Health Status Inventory. Speech recognition in noise was significantly poorer for AHL subjects [-0.12 dB signal-to-noise ratio (SNR) in dichotic (with speech presented to the poorer ear and noise to the better ear), -1.72 dB in diotic and -6.84 dB in reverse-dichotic conditions] compared to NHL (-4.98 dB in diotic and -9.58 dB in dichotic conditions). Scores for quality-of-life questionnaires were significantly below norms. Significant correlations were found between the SRT for the dichotic condition and the SSQ total score (r = -0.38, p = 0.01), and pure-tone average thresholds for both groups.

Identification and evaluation of cochlear implant candidates with asymmetrical hearing loss.

OBJECTIVE: Recommendation for cochlear implant (CI) treatment for individuals with severe to profound single-sided deafness (SSD) and asymmetrical hearing loss (AHL) is on the rise. This raises the need for greater consistency in the definition of CI candidacy for these cases and in the assessment methods of patient-related benefits to permit effective comparison and interpretation of the outcomes with both conventional and implantable options across studies. METHOD: During a dedicated seminar on implant treatment in AHL patients, the panellists of the closing round table reviewed the clinical experience presented with the aim to define clear audiometric characteristics for both AHL and SSD cases, as well as a common data set enabling consistent evaluation of hearing benefits in this population. CONCLUSIONS: The panellists agreed on a clear differentiation between AHL and SSD CI candidates, defining average pure-tone thresholds up to 4 kHz for better and poorer ears. Agreement was reached on a minimum set of assessment procedures, and included the necessity of trials with conventional CROS/BICROS hearing aids and bone conduction devices before considering CI treatment. Objective assessment of sound localisation abilities was identified as the most relevant criterion to quantify performance before and after treatment. In parallel, subjective assessment of overall hearing ability was recommended via the Speech, Spatial and Qualities of hearing questionnaire. Longitudinal follow-up of these parameters and the hours of daily use were considered essential to reflect the potential treatment benefits for this population. The consistency in the data collection and its report will further support health authorities in their decision on acceptable gains from available hearing loss treatment options.

Effect of corticosteroids on facial function after cerebellopontine angle tumor removal: a double-blind study versus placebo.

The aim of this study was to assess the effect of corticosteroids administered intra- and postoperatively on the occurrence of facial palsy after a cerebellopontine angle (CPA) tumor resection, and to investigate pre- and intraoperative prognostic factors. A multicenter, prospective, randomized, double-blind and versus-placebo study was conducted between 2006 and 2010. Three hundred and ten patients operated on for a CPA tumor (96% vestibular schwannomas, 4% miscellaneous) were included by five participating centers. The population was stratified into patients with small (≤15 mm CPA on axial MRI views) and large tumors. In each group, patients were randomized to receive corticosteroid (1 mg/kg/day i.v. methylprednisolone intraoperatively and at postoperative days 1-5) or placebo. Steroids did not affect the facial function at postoperative days 1, 8 and 30 in patients with small or large tumors as evaluated by House and Brackmann grading.

Speech prosody perception in cochlear implant users with and without residual hearing.

OBJECTIVES: The detection of fundamental frequency (F0) variations plays a prominent role in the perception of intonation. Cochlear implant (CI) users with residual hearing might have access to these F0 cues. The objective was to study if and how residual hearing facilitates speech prosody perception in CI users. DESIGN: The authors compared F0 difference limen (F0DL) and question/statement discrimination performance for 15 normal-hearing subjects (NHS) and two distinct groups of CI subjects, according to the presence or absence of acoustic residual hearing: one "combined group" (n = 11) with residual hearing and one CI-only group (n = 10) without any residual hearing. To assess the relative contribution of the different acoustic cues for intonation perception, the sensitivity index d' was calculated for three distinct auditory conditions: one condition with original recordings, one condition with a constant F0, and one with equalized duration and amplitude. RESULTS: In the original condition, combined subjects showed better question/statement discrimination than CI-only subjects, d' 2.44 (SE 0.3) and 0.91 (SE 0.25), respectively. Mean d' score of NHS was 3.3 (SE 0.06). When F0 variations were removed, the scores decreased significantly for combined subjects (d' = 0.66, SE 0.51) and NHS (d' = 0.4, SE 0.09). Duration and amplitude equalization affected the scores of CI-only subjects (mean d' = 0.34, SE 0.28) but did not influence the scores of combined subjects (d' = 2.7, SE 0.02) or NHS (d' = 3.3, SE 0.33). Mean F0DL was poorer in CI-only subjects (34%, SE 15) compared with combined subjects (8.8%, SE 1.4) and NHS (2.4%, SE 0.05). In CI subjects with residual hearing, intonation d' score was correlated with mean residual hearing level (r = -0.86, n = 11, p < 0.001) and mean F0DL (r = 0.84, n = 11, p < 0.001). CONCLUSION: Where CI subjects with residual hearing had thresholds better than 60 dB HL in the low frequencies, they displayed near-normal question/statement discrimination abilities. Normal listeners mainly relied on F0 variations which were the most effective prosodic cue. In comparison, CI subjects without any residual hearing had poorer F0 discrimination and showed a strong deficit in speech prosody perception. However, this CI-only group appeared to be able to make some use of amplitude and duration cues for statement/question discrimination.

Visual activity predicts auditory recovery from deafness after adult cochlear implantation.

Modern cochlear implantation technologies allow deaf patients to understand auditory speech; however, the implants deliver only a coarse auditory input and patients must use long-term adaptive processes to achieve coherent percepts. In adults with post-lingual deafness, the high progress of speech recovery is observed during the first year after cochlear implantation, but there is a large range of variability in the level of cochlear implant outcomes and the temporal evolution of recovery. It has been proposed that when profoundly deaf subjects receive a cochlear implant, the visual cross-modal reorganization of the brain is deleterious for auditory speech recovery. We tested this hypothesis in post-lingually deaf adults by analysing whether brain activity shortly after implantation correlated with the level of auditory recovery 6 months later. Based on brain activity induced by a speech-processing task, we found strong positive correlations in areas outside the auditory cortex. The highest positive correlations were found in the occipital cortex involved in visual processing, as well as in the posterior-temporal cortex known for audio-visual integration. The other area, which positively correlated with auditory speech recovery, was localized in the left inferior frontal area known for speech processing. Our results demonstrate that the visual modality's functional level is related to the proficiency level of auditory recovery. Based on the positive correlation of visual activity with auditory speech recovery, we suggest that visual modality may facilitate the perception of the word's auditory counterpart in communicative situations. The link demonstrated between visual activity and auditory speech perception indicates that visuoauditory synergy is crucial for cross-modal plasticity and fostering speech-comprehension recovery in adult cochlear-implanted deaf patients.

Reliability of cone beam computed tomography in scalar localization of the electrode array: a radio histological study.

Postoperative imaging plays a growing role in clinical studies concerning prognostic factors in cochlear implantation. Indeed, intracochlear position of the cochlear implant has recently been identified as a contributor in functional outcomes and radiological tools must be accurate enough to determine the final placement of the electrode array. The aim of our study was to validate cone beam computed tomography as a reliable technique for scalar localization of the electrode array. We performed therefore a temporal bone study on ten specimens that were implanted with a perimodiolar implant prototype. Cone beam reconstructions were performed and images were analyzed by two physicians both experienced in cochlear implant imaging, who determined the scalar localization of the implant. Temporal bones then underwent histological control to document this scalar localization and hypothetical intracochlear lesions. In four cases, a dislocation from scala tympani to scala vestibuli was suspected on cone beam reconstructions of the ascending part of the basal turn. In three of these four specimens, dislocation in pars ascendens was confirmed histologically. In the remaining temporal bone, histological analysis revealed an elevation with rupture of the basilar membrane. Histological assessment revealed spiral ligament tearing in another bone. We conclude that cone beam is a reliable tool to assess scalar localization of the selectrode array and may be used in future clinical studies.

Innovative protocol of an exploratory study evaluating the acceptability of a humanoid robot at home of deaf children with cochlear implants.

The purpose of this paper is to introduce a research methodology for the assessment of the acceptability of a humanoid robot at home for children with cochlear implants (CI). The quality of audiology rehabilitation for cochlear implanted child administrated at the hospital with pluri-weekly sessions is a major prognostic factor in the outcome on communications abilities, but represents also a constraint for families related to the access to care that are more difficult. Further, home training with tools would balance the equitable distribution of care in the territory and promote the child's progress. The humanoid robot should allow an ecological approach to this complementary training. Before developing this approach, it is necessary to study the acceptability of the humanoid robot at home, both by cochlear implanted child and their families. Ten families were chosen to have a humanoid robot at home, to explore their acceptability of the humanoid robot Pepper. The study lasts for 1 month per participants (i.e. cochlear implemented children and parent). Participants were invited to use the robot at home as much as they want. The humanoid robot Pepper was able to communicate and proposed activities not related to rehabilitation. Once a week during the study, data were collected from participants (questionnaires and robot's logs) and the smooth running of the study was checked. Questionnaires are used to evaluate the acceptability of the robot by children and parents. User data from the robot's logs are used to quantify the time and the actual use of the robot over the period of the study. Results of the experimentation will be reported, once all 10 participants have completed their passation. The robot is anticipated to be used and accepted by children with cochlear implants and their families. Clinical trial registration: Clinical Trials ID: NCT04832373; https://clinicaltrials.gov/.

Evolution of crossmodal reorganization of the voice area in cochlear-implanted deaf patients.

Psychophysical and neuroimaging studies in both animal and human subjects have clearly demonstrated that cortical plasticity following sensory deprivation leads to a brain functional reorganization that favors the spared modalities. In postlingually deaf patients, the use of a cochlear implant (CI) allows a recovery of the auditory function, which will probably counteract the cortical crossmodal reorganization induced by hearing loss. To study the dynamics of such reversed crossmodal plasticity, we designed a longitudinal neuroimaging study involving the follow-up of 10 postlingually deaf adult CI users engaged in a visual speechreading task. While speechreading activates Broca's area in normally hearing subjects (NHS), the activity level elicited in this region in CI patients is abnormally low and increases progressively with post-implantation time. Furthermore, speechreading in CI patients induces abnormal crossmodal activations in right anterior regions of the superior temporal cortex normally devoted to processing human voice stimuli (temporal voice-sensitive areas-TVA). These abnormal activity levels diminish with post-implantation time and tend towards the levels observed in NHS. First, our study revealed that the neuroplasticity after cochlear implantation involves not only auditory but also visual and audiovisual speech processing networks. Second, our results suggest that during deafness, the functional links between cortical regions specialized in face and voice processing are reallocated to support speech-related visual processing through cross-modal reorganization. Such reorganization allows a more efficient audiovisual integration of speech after cochlear implantation. These compensatory sensory strategies are later completed by the progressive restoration of the visuo-audio-motor speech processing loop, including Broca's area.

Functional Reorganization of the Central Auditory System in Children with Single-Sided Deafness: A Protocol Using fNIRS.

In children, single-sided deafness (SSD) affects the development of linguistic and social skills and can impede educational progress. These difficulties may relate to cortical changes that occur following SSD, such as reduced inter-hemispheric functional asymmetry and maladaptive brain plasticity. To investigate these neuronal changes and their evolution in children, a non-invasive technique is required that is little affected by motion artifacts. Here, we present a research protocol that uses functional near-infrared spectroscopy (fNIRS) to evaluate the reorganization of cortical auditory asymmetry in children with SSD; it also examines how the cortical changes relate to auditory and language skills. The protocol is designed for children whose SSD has not been treated, because hearing restoration can alter both brain reorganization and behavioral performance. We propose a single-center, cross-sectional study that includes 30 children with SSD (congenital or acquired moderate-to-profound deafness) and 30 children with normal hearing (NH), all aged 5-16 years. The children undergo fNIRS during monaural and binaural stimulation, and the pattern of cortical activity is analyzed using measures of the peak amplitude and area under the curve for both oxy- and deoxyhemoglobin. These cortical measures can be compared between the two groups of children, and analyses can be run to determine whether they relate to binaural hearing (speech-in-noise and sound localization), speech perception and production, and quality of life (QoL). The results could be of relevance for developing individualized rehabilitation programs for SSD, which could reduce patients' difficulties and prevent long-term neurofunctional and clinical consequences.

Stapedotomy Versus Hearing Aids in the Management of Conductive Hearing Loss Caused by Otosclerosis: A Prospective Comparative Study.

OBJECTIVE: To compare the outcomes of patients with unilateral otosclerosis treated consecutively by a hearing aid then stapedotomy. STUDY DESIGN: Monocentric, nonrandomized, prospective, longitudinal, cohort study. SETTING: Tertiary university hospital. PATIENTS: Adult patients with a unilateral conductive hearing loss of at least 30 dB caused by otosclerosis. INTERVENTIONS: Consecutive treatment by an external hearing aid followed by stapedotomy. MAIN OUTCOME MEASURES: Differences between hearing aids and stapedotomy in quality of life, pure-tone audiometry, binaural hearing, tinnitus severity, and patient satisfaction. RESULTS: Twenty-two patients were included, of which 20 (91%) underwent stapedotomy. Stapedotomy demonstrated increased quality of life according to Glasgow Health Status Inventory scores versus hearing aids (+10.4 ± 9.4 [p = 0.0001]). Stapedotomy versus hearing aids showed improved pure-tone averages (-11.1 ± 11.0 dB [p = 0.002]) and air-bone gaps (-11.8 ± 10.7 dB [p = 0.0006]). Stapedotomy was superior to hearing aids for speech-in-noise recognition in the reverse dichotic condition (-8.4 ± 26.9 dB [p = 0.004]) and showed improved sound localization accuracy in root mean square error (-14.5 ± 24.5 degrees [p = 0.02]). Stapedotomy, but not hearing aids, showed improved patient self-evaluated tinnitus after baseline adjustment according to the Tinnitus Handicap Inventory (-8.0 ± 13.4 [p = 0.02]) and visual analog scale for tinnitus intensity (-28.7 ± 34.1 [p = 0.006]). Overall, patients were more satisfied with surgery versus hearing aids. CONCLUSIONS: Stapedotomy remains more effective compared with hearing aids with greater improvements in quality of life, patient satisfaction, hearing outcomes, and self-evaluated tinnitus.