Cochlear Implant Recipients Research Articles

Individualized post-operative prediction of cochlear implantation outcomes in children with prelingual deafness using functional near-infrared spectroscopy.

The goal of this study was to develop an objective measure and predictor of cochlear implantation (CI) outcomes using functional near-infrared spectroscopy (fNIRS) for young children with prelingual deafness. Sound-evoked hemodynamic responses were recorded from auditory and language-related cortical regions of 47 child CI recipients (35.47 ± 17.24 months of age) using fNIRS shortly after CI activation (0.26 ± 0.30 months). There were four sound conditions (natural speech, instrumental music, multi-speaker babble noise, and speech-in-noise). Post-CI auditory and verbal communication performance was evaluated using clinical questionnaires with caretakers. Both classification and individualized regression models were constructed to predict post-CI behavioral improvement from fNIRS data using support vector machine (SVM) learning algorithms. Auditory cortical responses shortly after CI hearing onset yielded highly accurate prediction of behavioral development in young CI children. For classification models, optimal prediction was achieved using cortical responses to two or more sound conditions, with the highest accuracy of 98.20% (precision = 98.17%, sensitivity = 98.96%, area under the curve of the receiver operating characteristic curve = 99.61%) obtained with the combination of speech, noise, and music stimuli. Similarly, for regression models, best prediction of individual development was achieved using three (highest r = 0.919) or four (r = 0.966) sound conditions. The predictability of cortical responses far outperformed (Cohen's d: 18.56) that of the collection of audiological and demographic parameters (classification accuracy: 0.62) under the same SVM algorithms and could not benefit from the inclusion of the latter. Machine learning models using auditory cortical hemodynamic responses shortly after CI activation were able to predict individualized post-CI behavioral improvement in children with prelingual deafness. Level 5.

Postoperative Auditory Progress in Cochlear-Implanted Children With Auditory Neuropathy.

This study aims to evaluate the effect of auditory neuropathy spectrum disorder (ANSD) on postoperative auditory perception and listening difficulties in pediatric cochlear implant (CI) recipients. The Children's Auditory Perception Test (CAPT) assesses auditory perception skills, and the Children's Home Inventory of Listening Difficulties (CHILD) Scale evaluates daily listening difficulties. The study involved pediatric CI recipients (n = 40) aged between 5 and 7 years, with and without diagnosis of ANSD. The research ensured homogeneity across various factors, including chronological age, age at diagnosis, age at initial implantation, bilateral simultaneous surgery, etiologies of hearing loss, and family education level. The findings have demonstrated that children without ANSD exhibited better performance in integrating visual-auditory stimuli and overall listening performance, distant sound source scores, and noisy environment scores (respectively p = .047, p = .001, p = .028, and p = .010). Additionally, children with better speech perception also have a better ability to integrate audiovisual stimuli (p = .005, r = .438). There are significant differences in postoperative listening skills and auditory perceptions between children with and without an ANSD who have CIs. Accordingly, children without an ANSD perform better.

Are tinnitus burden and tinnitus exacerbation after cochlear implantation influenced by insertion technique, array dislocation, and intracochlear trauma?

Although numerous studies suggest that cochlear implantation (CI) generally alleviates the overall burden of tinnitus, certain patients experience tinnitus exacerbation following CI. The exact cause of this exacerbation is still uncertain. This prospective study aimed to investigate whether cochlear trauma, resulting from scalar dislocation of the electrode array, affected postoperative tinnitus intensity, tinnitus burden, and speech perception. Additionally, the influence of CI insertion technique, insertion depth, insertion angle, and cochlear morphology on postoperative tinnitus was assessed. We evaluated 66 CI recipients preoperatively at 2 days, 4 weeks, and 12- and 24-months following surgery. Digital volume tomography was employed to document scalar position, insertion depth, and cochlear morphology postoperatively. Speech perception was analyzed using Freiburg monosyllables. The tinnitus burden was evaluated using the tinnitus questionnaire, while the tinnitus intensity was quantified using a visual analog scale. Study results pertaining to tinnitus intensity and burden did not reveal a significant difference in elevation regarding scalar position and dislocation after CI surgery compared to preoperative tinnitus levels. However, dislocation was only identified in four patients, and scala vestibuli insertions were observed in two patients. Comparing preoperative and 1-year postoperative outcomes, CI was noted to substantially reduce the tinnitus burden. When the speech processor was worn, the tinnitus intensity was significantly diminished. In comparison to round window (RW) insertion, the insertion technique cochleostomy (CS) did not exhibit a significant difference or a trend toward increased tinnitus intensity. This study demonstrates that CI significantly decreases the tinnitus burden. The observation implies that the electrical stimulation of the auditory pathway, facilitated by wearing the speech processor, significantly reduced the tinnitus intensity. The incidence of dislocations and scala vestibuli insertions has declined to the extent that it is no longer feasible to formulate statistically significant conclusions.

Associated factors and outcomes for quality of life in children receiving cochlear implantation before seven years of age.

To evaluate the relationship of cochlear implant-related factors with quality of life (QOL) outcomes in pediatric cochlear implantation (CI) recipients. In this cross-sectional study, data from 146 children who received CI before 7 years of age were collected. QOL was measured using the Children using Hearing Implants Quality of Life (CuHI-QoL) questionnaire. Auditory and language abilities were measured using categories of auditory performance II(CAP-II) scale and speech intelligibility rating (SIR) scale. The reliability and validity of the CuHI-QOL scale were tested using internal consistency tests and correlation analysis, respectively. Bivariate correlations were used to compare CuHI-QOL scores and educational placements to cochlear implant-related factors. QOL scores were further compared using ANOVA in different groups based on age at CI with different durations of implant use. The mean total CuHI-QOL scores was 60.13 (SD 8.97). The Cronbach's alpha of overall CuHI-QOL scale was 0.820. The CuHI-QOL total score was strongly to moderately correlated with CAP score (r = 0.542), SIR score (r = 0.545), duration of implant use (r = 0.403), and educational placement (r = 0.478). ANOVA showed the CuHI-QOL scores after 5 years post-CI were higher than those less than 2 years post-CI in children implanted ≤ 3 years of age. Good QOL could be obtained for children with CI and were significantly associated with young age at implantation, good auditory and speech abilities, speech rehabilitation training pre-CI, long duration of cochlear implant use, and mainstream educational placement.

Clinical Outcomes for Adult Single-Sided Deafness Cochlear Implantees Exceeding the 5% Candidacy Criterion

Objectives: While single-sided deafness cochlear implants (SSD-CIs) have now received regulatory approval in the United States, candidate-ear candidacy criteria (no better than 5% word-recognition score) are stricter than for traditional CI candidates (50 to 60% speech recognition, best-aided condition). SSD implantation in our center began before regulatory approval, using a criterion derived from traditional candidacy: 50% consonant-nucleus-consonant (CNC) word-identification score in the candidate ear. A retrospective analysis investigated whether SSD patients exceeding the 5% CNC criterion nevertheless benefitted from a CI as assessed by spatial-hearing tests (speech understanding in noise [SIN] and localization) and by a patient-reported outcome measure quality-of-life instrument validated for patients with CIs. Design: A retrospective chart review assessed the clinical experience of a single CI center. Subjects consisted of 27 adult CI recipients with SSD (N = 21) or asymmetric hearing loss (AHL; N = 6) implanted since September 2019 with at least 3 months of postoperative follow-up. Patients with revision surgery or simultaneous labyrinthectomy and CI surgery were excluded from the sample. Subjects were divided into 2 groups based on preoperative CNC scores measured under best-aided conditions with a behind-the-ear hearing aid in the sound field at 0.9 m from a front loudspeaker, and the better ear masked using an insert earphone with 45 dB HL speech-weighted noise. The “MEETS” group had preoperative CNC word scores <5%; the “EXCEEDS” group had scores >5%. The clinical protocol also included intelligibility tests using AzBio sentences in the same test conditions as CNC; binaural spatial testing (broadband-noise sound localization, and matrix-sentence speech-reception thresholds in spatially separated noise) using a custom-built 7-speaker array; and the CI Quality of Life (CIQOL) instrument. To evaluate CI benefit, preoperative unaided performance was compared with postoperative binaural (acoustic ear + CI ear) performance at a clinic visit closest to 6 months postsurgery. Results: Of 27 SSD-CI recipients, 11 subjects exceeded the 5% preoperative CNC candidacy criterion. Both the MEETS and EXCEEDS groups improved significantly on all 5 primary study outcome measures (CI-alone CNC and AzBio, binaural SIN and sound localization, and CIQOL). The only statistically significant differences observed between the MEETS and EXCEEDS groups were that preoperative CNC and AzBio scores were significantly higher for the EXCEEDS group, as expected given that the groups were defined based on preoperative speech-perception scores in quiet. There were no statistically significant differences between the MEETS and EXCEEDS groups in postoperative scores in any test or in the magnitude of the improvement from preoperative to postoperative assessment. Conclusions: SSD- and AHL-CI recipients exceeding the 5% CNC preoperative candidacy criterion significantly improved in CI-alone speech perception, spatial hearing, and subjectively reported CIQOL outcomes and the observed benefits were indistinguishable from SSD- and AHL-CI recipients who met the 5% criterion. A less-restrictive SSD-CI and AHL-CI candidacy criterion should be considered, and larger-scale clinical trials to evaluate CI efficacy using a less-stringent candidate-ear criterion are warranted.

Good cochlear implantation outcomes in subjects with mono-allelic WFS1-associated sensorineural hearing loss – a case series

Objective This study aimed to evaluate long-term cochlear implant (CI) outcomes in individuals with mono-allelic pathogenic variants in WFS1, which is associated with both Wolfram-like syndrome and DFNA6/14/38. Design Retrospective case series. Study sample Seven CI recipients, ranging from eight months to 58 years of age, were included in the study, including four with Wolfram-like syndrome and three with DFNA6/14/38. A total of ten cochlear implantations were performed among these subjects. Results At one-year post-implantation, a mean phoneme score of 90 ± 9% at 65 dB SPL in quiet was found, which remained stable up to ten years post-implantation with a mean phoneme score of 94 ± 6%. Despite these excellent outcomes, one subject achieved no speech recognition with CI and eventually became a non-user. This individual had a prolonged absence of auditory stimulation prior to implantation and encountered multiple challenges during rehabilitation. Conclusion Individuals with Wolfram-like syndrome or DFNA6/14/38 demonstrate consistently good outcomes following implantation, which remain stable over time. These findings affirm cochlear implantation as an effective rehabilitation option for these individuals. Furthermore, the stable and good CI outcomes contradict the suggested link between WFS1-associated sensorineural hearing loss and auditory neuropathy.

Changes in Outcomes Expectations During the Cochlear Implant Evaluation Process.

Patient expectations are a critical factor in determining cochlear implant (CI) candidacy. However, minimal data are available on how potential CI recipients develop their expectations and if expectations can be modified by providers. In addition, there is little insight into the resources patients use to inform their decision to undergo implantation. This project aims to assess (1) the role of the CI evaluation (CIE) process on patients' expectations, (2) the extent to which patients' pre-CI outcome expectations can be modified, (3) the information patients use to inform their expectations, and patients' preferences for the discussion/display of potential CI outcomes. Prospective mixed methods study of 32 adult CI patients undergoing CIEs. Outcome measures included: pre-CI Cochlear Implant Quality of Life-35 Profile scores (CIQOL-35 Profile); pre-CIE/post-CIE/day of surgery CIQOL-Expectations scores; post-CIE/day of surgery Decisional Conflict Scale (DCS) scores; and pre-CI aided CNC-word and AzBio sentence scores. Thematic analyses of key informant interviews with 19 potential CI recipients were also performed. In aim 1, CI CIQOL-Expectation domain scores remained essentially unchanged following the CIE when averaged across all participants (d = 0.01 to 0.17). However, changes in expectations were observed for many participants at the individual level. Regarding the second aim, participants with higher pre-CIE expectations showed a decrease in expectations following the CIE for all CIQOL domains except emotional and social (d = -0.27 to -0.77). In contrast, the only significant change in participants with lower expectations was an increase in expectations in the environment score from pre-CIE to the day of surgery (d = 0.76). Expectations remained essentially unchanged or continued to change in the same direction between the post-CIE and the day of surgery, narrowing the gap between participants with higher and lower expectations. Overall, participants demonstrated low overall conflict related to their decision to proceed with cochlear implantation (mean DCS of 11.4 post-CIE and 14.2 at time of surgery out of 100) but DCS scores were higher for participants with lower pre-CIE expectations (d = 0.71). In aim 3, key informant interviews demonstrated no differences between the low- and high expectation cohorts regarding resources used to develop their perception of CI outcomes. Potential CI recipients placed high value in talking with patients who had previously received a CI, and preferred discussing CI functional abilities via clinical vignettes described in the CIQOL Functional Staging System rather than by discussing speech recognition or CIQOL-35 Profile scores. The results of the present study suggest that, although overall expectations averaged across the cohort remained essentially unchanged, individual participants' pre-CI expectations can be modified and there is value in measuring these expectations using the CIQOL-Expectations tool to determine if they are realistic. This information can then be utilized during personalized counseling to present a more accurate representation of likely CI outcomes for each patient. Discussions between potential CI recipients and current CI users may also provide valuable information to inform their expectations. In addition, communicating potential CI benefits using CIQOL functional stages and associated clinical vignettes may result in more realistic patient expectations and support shared decision-making related to CI surgery.

When to Start Computer-Based Auditory Training After Cochlear Implantation: Effects on Quality of Life and Speech Recognition.

Computer-based auditory training (CBAT) has been shown to improve outcomes in adult cochlear implant (CI) users. This study evaluates in new CI users whether starting CBAT within 3 months of activation or later impacts CI outcomes. Prospective natural experiment. Tertiary academic medical center. Sixty-five new adult CI users. CBAT use over the first-year postactivation. Speech recognition scores and CIQOL-35 Profile score improvements between CI recipients who started CBAT resources early (<3 mo) and late (3-12 mo) postactivation. A total of 43 CI recipients started using CBAT within 3 months postactivation (early) and 22 after 3 months (late). Patients who used CBAT within 3 months postactivation showed significantly greater improvement in consonant-nucleus-consonant words (CNCw) (48.3 ± 24.2% vs 27.8 ± 24.9%; d = 0.84), AzBio Sentences in quiet (55.1 ± 28.0% vs 35.7 ± 36.5%; d = 0.62), and CIQOL-35 listening domain scores (18.2 ± 16.3 vs 6.9 ± 12.9, d = 0.73 [0.023, 1.43]), at 3 months postactivation, compared to those who had not yet initiated CBAT. However, by 12 months postactivation, after which all CI recipients had started CBAT, there were no differences observed between patients who started CBAT early or late in speech recognition scores (CNCw: d = 0.26 [-0.35, 0.88]; AzBio: d = 0.37 [-0.23, 0.97]) or in any CIQOL global or domain score (d-range = 0.014-0.47). Auditory training with self-directed computer software (CBAT) may yield speech recognition and quality-of-life benefits for new adult CI recipients. While early users showed greater improvement in outcomes at 3 months postactivation than users who started later, both groups achieved similar benefits by 12 months postactivation.

EVALUATION OF REMOTE CHECK IN CHILDREN WITH COCHLEAR IMPLANTS

ObjectiveThis study evaluates the feasibility of reducing in-person appointments by utilizing Remote Check (RC) in pediatric cochlear implant (CI) recipients and investigates the most suitable age range for implementing RC. MethodsFifty-eight pediatric CI recipients, aged 1 to 17 years, were evaluated using a web-based RC application by audiologists. Most (84.5%) used verbal communication. Inclusion criteria required stable map status, caregiver tech proficiency, and a compatible phone. ResultsRemote assessments were beneficial, with 89.7% of participants successfully completing RC. Aided threshold tests (ATT) were completed in 73.2% of participants, while speech-in-noise tests (Digit Triplet Test, DTT) were completed in 47.3%. Children as young as 4 successfully completed ATT, while a minimum age of 7 was required for DTT. A significant relationship between age and test success was demonstrated. Verbally communicative children had higher completion success rates. Parental education was significantly correlated with DTT success, with higher success rates in children whose parents had undergraduate degrees. With RC use, 69% of children did not need clinic visits, emphasizing the need for personalized and remote support for optimal cochlear implant performance. In-person appointments were primarily required due to concerns about the duration of device usage. ConclusionThe study confirms the effectiveness and feasibility of using RC in pediatric CI users, even as young as one year old with stable aided hearing. The findings advocate for the integration of RC into routine follow-up protocols, offering a more accessible option for enhanced patient care.

Evaluating cochlear implant outcomes in DFNA9 subjects: a comprehensive study on cerebral white matter lesions and vestibular abnormalities.

This study assessed whether the Fazekas score could account for the variability in cochlear implantation (CI) outcomes among individuals with DFNA9 and evaluated signal loss in the semicircular canals (SCCs) on magnetic resonance imaging (MRI) among individuals with DFNA9. This retrospective cross-sectional study included CI recipients with DFNA9. Pre-implantation MRI-scans were reviewed to determine the Fazekas score, localizing and grading cerebral white matter lesions (WML), and identify abnormalities in the SCCs. CI performance was assessed by evaluating phoneme scores one year post-implantation. The function of the SCCs was evaluated using rotatory chair testing with electronystagmography (ENG) and the video Head Impulse Test (vHIT). Forty-five subjects (49 ears) were enrolled. The phoneme scores significantly improved from 35% (IQR 11-50) pre-implantation to 84% (IQR 76-90) one year post-implantation. No correlation was observed between the Fazekas score and the one-year post-implantation phoneme score (rsp=0.003, p = 0.986). Signal loss in at least one SCCs was detected in 97.7% of subjects and 77.8% of ears. There was no correlation between vestibular test results and fluid signal loss in the SCCs on MRI. Most individuals with DFNA9 show improved speech recognition with CI. The observed variability in CI outcomes was not linked to the Fazekas score. Additionally, our study confirms a high prevalence of focal sclerosis in DFNA9. Recognizing the limitations of this study, further research is needed to explore the predictive role of the Fazekas score on CI outcomes and its relationship with vestibular function.

Tonotopic and Default Frequency Fitting for Music Perception in Cochlear Implant Recipients

Cochlear implants are an effective technique for enhancing speech perception abilities in quiet environments for people with severe to profound deafness. Nevertheless, complex sound signals perception, such as music perception, remains challenging for cochlear implant users. To assess the benefit of a tonotopic map on music perception in new cochlear implant users. A prospective, randomized, double-blind, 2-period crossover study including 26 new cochlear implant users was performed over a 6-month period (June 2021 to November 2021). An anatomical tonotopic map was created using postoperative flat-panel computed tomography and a reconstruction software based on Greenwood function. New cochlear implant users older than 18 years with bilateral severe to profound sensorineural hearing loss or complete hearing loss for less than 5 years were selected in the University Hospital Centre of Rennes in France. The trial was conducted from June to November 2021 (inclusion) and to February 2022 (end of the assessment procedure at 12 weeks postactivation), and the analysis itself was completed in December 2022. Each participant was randomized to receive a conventional map followed by a tonotopic map or vice versa. Participants performed pitch-scaling tasks (multidimensional qualitative assessment, melodic contour identification, melodic recognition test) after 6 weeks of each setting. Thirteen participants were randomized to each sequence. Two of the 26 participants recruited (1 in each sequence) had to be excluded due to the COVID-19 pandemic. The multidimensional qualitative assessment (Gabrielsson test), melodic contour identification, and melodic recognition scores were significantly higher with the tonotopic setting than the conventional one (mean effect [ME], 7.8; 95% CI, 5.0-10.5; ME, 12.1%; 95% CI, 5.7%-18.4%; ME, 14.4%, 95% CI, 8.5%-20.2%; and ME, 2.1, 95% CI, 1.7-2.5, respectively). Among the different dimensions evaluated by the Gabrielsson test, the mean scores for clarity, spaciousness, fullness, nearness, and total impression were significantly higher with tonotopic fitting. Ninety-two percent of the participants kept the tonotopy-based map after the study period. In this randomized clinical trial of patients with new cochlear implants, a tonotopic-based fitting was associated with better results in perception of complex sound signals such as music listening experience. ClinicalTrials.gov Identifier: NCT04922619.

Music Perception and Music-Related Quality of Life in Adult Cochlear Implant Users: Exploring the Need for Music Rehabilitation.

Cochlear implant (CI) users face difficulties in accurately perceiving basic musical elements such as pitch, melody, and timbre. Music significantly affects the quality of life (QoL) of CI users. Individually and culturally influenced music perception exceeds psychophysical measures in capturing the subjective music enjoyment of CI users. Understanding the music perception, enjoyment, and habits of CI users is crucial for approaches to improve music-related QoL (MuRQoL). Therefore, this study aims to investigate music perception skills, experiences, and participation in music activities in a large group of adult CI users, and to understand the importance of these factors and their impact on QoL of CI users. This study included 214 CI recipients with diverse auditory experiences who were aged between 18 and 65 years and were unilateral, bimodal, or bilateral users for at least 1 year and 193 normal hearing (NH) controls. All participants completed the information forms and the MuRQoL questionnaire. To assess the impact of music on QoL and identify personalized rehabilitation needs, the scores for each question in both parts of the questionnaire were intersected on a matrix. Data were presented in detail for the CI group and compared between CI and NH groups. A statistically significant difference was found between the matched CI and NH groups in favor of the NH group in terms of music perception and music engagement. Participants who received music education at any point in their lives had significantly higher MuRQoL questionnaire scores. There was no significant relationship found between the duration of auditory rehabilitation, pre-CI hearing aid usage, music listening modality, and MuRQoL questionnaire scores. Unilateral CI users had significantly lower scores in music perception and music engagement subsections compared with bimodal and bilateral CI users. Also, it was found that music had a strong negative impact on QoL in 67/214 of the CI users. Although CI users scored significantly lower than NH individuals on the first part of the questionnaire, which asked about musical skills, enjoyment, and participation in musical activities, findings suggest that CI users value music and music enjoyment just as much. The study reveals the influence of factors such as education level, age, music education, type of hearing loss and auditory rehabilitation on music perception, music enjoyment, and participation in music activities through self-report. The results indicate that for many CI users, music has a strong negative impact on QoL, highlighting the need for personalized music interventions, the inclusion of self-report questionnaires, and music perception tests in clinical evaluations.

Impact of adult cochlear implantation on the partner relationship: a conceptual framework informed by cochlear implant recipient and partner perceptions

Purpose (1) To understand the impact of adult cochlear implantation on the partner relationship, as perceived by adult cochlear implant (CI) recipients and their intimate partners. (2) To generate a conceptual framework for guiding future research and clinical adult cochlear implantation interventions. Method Concept mapping, a participatory, mixed-method approach, was used for data collection, analysis and interpretation. Participants attended sessions to generate, sort and rate statements describing the changes in their relationship due to cochlear implantation. Participants included 15 CI recipients (mean age: 51.6 years; SD: 8.2) and 12 partners (mean age: 50.9 years; SD: 8.2). Results Five concepts emerged from the data, describing changes in the partner relationship following cochlear implantation: (1) Social Interactions, (2) Partner Involvement, (3) Communication, (4) Emotional Adjustment, and (5) Relationship Intimacy. The concept Relationship Intimacy was rated the highest in positivity and importance. Findings also underscored improved social interactions, communication dynamics, and emotional adjustment. Conclusions The Relationship Intimacy cluster emerged as pivotal, highlighting its essential role in improving post-implantation relationships. CI recipients experienced enhanced autonomy, while partners’ roles evolved regarding assistance and support. The diverse effects of implantation on partner relationships highlight the importance of adopting a patient- and family-centered approach to audiological intervention.

Auditory Localization Performance in Cochlear Implant Recipients With Single-Sided Deafness: The Challenges and Limitations of Current Outcome Metrics.

Acoustic localization accuracy metrics currently employed in clinical literature both overestimate and underestimate performance benefit of cochlear implantation (CI) for single-sided deafness (SSD). Although localization in SSD with CI has been investigated, performance characterization has relied heavily on average error. Although attractively concise, this measure may misrepresent performance. Here, we characterize frequency-specific localization on a granular level in subjects with CI for SSD as a critical analysis of localization outcome metrics. Eight CI recipients with SSD were recruited. Stimuli of broadband (BBN) and narrowband noise (NBN) at low (500 Hz), mid (1000 Hz), and high (4000 Hz) frequencies were presented in a semianechoic chamber. Localization accuracy was quantified in mean angular error (MAE) and linear regression slope. Use of a CI for SSD subjects improved localization performance by slope for all stimuli ( p ≤ 0.0033) to a level that was equal to normal-hearing controls at 1 and 4 kHz ( p ≥ 0.2281). MAE was also significantly improved for SSD subjects using CI for BBN stimuli ( p ≪ 0.0001); however, no statistically significant improvement in MAE was seen for NBN ( p ≥ 0.5773) with CI use. Descriptive analysis of individual subject performance highlights the reasons for contradictory results. There is inherent challenge in characterizing localization benefit for individuals with CI for SSD. Our data demonstrate the limitations of utilization of average error as the sole metric for outcome benefit. We emphasize the importance of continued research investigating alternative outcome measures as we work toward a more refined understanding of the potential benefits and limitations of cochlear implantation for SSD.

Evaluating Wideband Tympanometry Absorbance Changes in Cochlear Implant Recipients: Mechanical Insights and Influencing Parameters.

Background: Cochlear implant (CI) electrode insertion can change the mechanical state of the ear whereby wideband tympanometry absorbance (WBTA) may serve as a sensitive tool to monitor these mechanical changes of the peripheral auditory pathway after CI surgery. In WBTA, the amount of acoustic energy reflected by the tympanic membrane is assessed over a wide frequency range from 226 Hz to 8000 Hz. The objective of this study was to monitor changes in WBTA in CI recipients before and after surgery. Methods: Following otoscopy, WBTA measurements were conducted twice in both ears of 38 standard CI recipients before and in the range of 4 to 15 weeks after CI implantation. Changes from pre- to postoperative absorbance patterns were compared for the implanted as well as the contralateral control ear for six different frequencies (500 Hz, 750 Hz, 1000 Hz, 2000 Hz, 3000 Hz, 4000 Hz). Furthermore, the influence of the time point of the measurement, surgical access, electrode type, sex and side of the implantation were assessed for the implanted and the control ear in a linear mixed model. Results: A significant decrease in WBTA could be observed in the implanted ear when compared with the contralateral control ear for 750 Hz (p < 0.01) and 1000 Hz (p < 0.05). The typical two-peak pattern of WBTA measurements was seen in both ears preoperatively but changed to a one-peak pattern in the newly implanted ear. The linear mixed model showed that not only the cochlear implantation in general but also the insertion through the round window compared to the cochleostomy leads to a decreased absorbance at 750 and 1000 Hz. Conclusions: With WBTA, we were able to detect mechanical changes of the acoustical pathway after CI surgery. The implantation of a CI led to decreased absorbance in the lower frequencies and the two-peak pattern was shifted to a one-peak pattern. The result of the linear mixed model indicates that WBTA can detect mechanical changes due to cochlear implantation not only in the middle ear but also in the inner ear.

Speech Recognition and Subjective Hearing Abilities for Electric-Acoustic Stimulation Users With Unilateral Hearing Loss.

Some cochlear implant (CI) recipients with unilateral hearing loss (UHL) have functional acoustic hearing in the implanted ear, warranting the fitting of an ipsilateral electric-acoustic stimulation (EAS) device. The present study assessed speech recognition and subjective hearing abilities over time for EAS users with UHL. Prospective, repeated-measures. Tertiary referral center. Adult CI recipients with normal-to-moderate low-frequency acoustic thresholds in the implanted ear and a contralateral pure-tone average (0.5, 1, and 2 kHz) ≤25 dB HL. Participants were evaluated preoperatively and at 1, 3, and 6 months post-activation. Speech recognition for the affected ear was evaluated with CNC words in quiet. Masked speech recognition in the bilateral condition was evaluated with AzBio sentences in a 10-talker masker (0 dB SNR) for three spatial configurations: target from the front and masker either colocated with the target or presented 90 degrees toward the affected or contralateral ear. Responses to the Speech, Spatial, and Qualities of Hearing Scale subscales were used to assess subjective hearing abilities. Participants experienced significant improvements in CNC scores ( F(3,13) = 14.90, p < 0.001), and masked speech recognition in the colocated ( F(3,11) = 3.79, p = 0.043) and masker toward the contralateral ear ( F(3,11) = 4.75, p = 0.023) configurations. They also reported significantly better abilities on the Speech Hearing ( F(3,13) = 5.19, p = 0.014) and Spatial Hearing ( F(3,13) = 10.22, p = 0.001) subscales. Adults with UHL and functional acoustic hearing in the implanted ear experience significant improvements in speech recognition and subjective hearing abilities within the initial months of EAS use as compared with preoperative performance and perceptions.

Outcomes Using the Optimized Pitch and Language Strategy Versus the Advanced Combination Encoder Strategy in Mandarin-Speaking Cochlear Implant Recipients.

The experimental Optimized Pitch and Language (OPAL) strategy enhances coding of fundamental frequency (F0) information in the temporal envelope of electrical signals delivered to channels of a cochlear implant (CI). Previous studies with OPAL have explored performance on speech and lexical tone perception in Mandarin- and English-speaking CI recipients. However, it was not clear which cues to lexical tone (primary and/or secondary) were used by the Mandarin CI listeners. The primary aim of the present study was to investigate whether OPAL provides improved recognition of Mandarin lexical tones in both quiet and noisy environments compared with the Advanced Combination Encoder (ACE) strategy. A secondary aim was to investigate whether, and to what extent, removal of secondary (duration and intensity envelope) cues to lexical tone affected Mandarin tone perception. Thirty-two CI recipients with an average age of 24 (range 7 to 57) years were enrolled in the study. All recipients had at least 1 year of experience using ACE. Each subject attended two testing sessions, the first to measure baseline performance, and the second to evaluate the effect of strategy after provision of some take-home experience using OPAL. A minimum take-home duration of approximately 4 weeks was prescribed in which subjects were requested to use OPAL as much as possible but were allowed to also use ACE when needed. The evaluation tests included recognition of Mandarin lexical tones in quiet and in noise (signal to noise ratio [SNR] +5 dB) using naturally produced tones and duration/intensity envelope normalized versions of the tones; Mandarin sentence in adaptive noise; Mandarin monosyllabic and disyllabic word in quiet; a subset of Speech, Spatial, and Qualities of hearing questionnaire (SSQ, speech hearing scale); and subjective preference for strategy in quiet and noise. For both the natural and normalized lexical tone tests, mean scores for OPAL were significantly higher than ACE in quiet by 2.7 and 2.9%-points, respectively, and in noise by 7.4 and 7.2%-points, respectively. Monosyllabic word recognition in quiet using OPAL was significantly higher than ACE by approximately 7.5% points. Average SSQ ratings for OPAL were significantly higher than ACE by approximately 0.5 points on a 10-point scale. In quiet conditions, 14 subjects preferred OPAL, 7 expressed a preference for ACE, and 9 reported no preference. Compared with quiet, in noisy situations, there was a stronger preference for OPAL (19 recipients), a similar preference for ACE (7 recipients), while fewer expressed no preference. Average daily take-home use of ACE and OPAL was 4.9 and 7.1 hr, respectively. For Mandarin-speaking CI recipients, OPAL provided significant improvements to lexical tone perception for natural and normalized tones in quiet and noise, monosyllabic word recognition in quiet, and subjective ratings of speech intelligibility. Subjects accessed both primary and secondary cues to lexical tone for perception in quiet and noise conditions. The benefits of lexical tone recognition were attributed to enhanced F0 rate cues encoded by OPAL, especially in a noisy environment. The OPAL strategy was well accepted by many of the Mandarin-speaking CI recipients.

Factors to Describe the Outcome Characteristics of a CI Recipient.

Background: In cochlear implant (CI) treatment, there is a large variability in outcome. The aim of our study was to identify the independent audiometric measures that are most directly relevant for describing this variability in outcome characteristics of CI recipients. An extended audiometric test battery was used with selected adult patients in order to characterize the full range of CI outcomes. Methods: CI users were recruited for this study on the basis of their postoperative results and divided into three groups: low (1st quartile), moderate (medium decentile), and high hearing performance (4th quartile). Speech recognition was measured in quiet by using (i) monosyllabic words (40-80 dB SPL), (ii) speech reception threshold (SRT) for numbers, and (iii) the German matrix test in noise. In order to reconstruct demanding everyday listening situations in the clinic, the temporal characteristics of the background noise and the spatial arrangements of the signal sources were varied for tests in noise. In addition, a survey was conducted using the Speech, Spatial, and Qualities (SSQ) questionnaire and the Listening Effort (LE) questionnaire. Results: Fifteen subjects per group were examined (total N = 45), who did not differ significantly in terms of age, time after CI surgery, or CI use behavior. The groups differed mainly in the results of speech audiometry. For speech recognition, significant differences were found between the three groups for the monosyllabic tests in quiet and for the sentences in stationary (S0°N0°) and fluctuating (S0°NCI) noise. Word comprehension and sentence comprehension in quiet were both strongly correlated with the SRT in noise. This observation was also confirmed by a factor analysis. No significant differences were found between the three groups for the SSQ questionnaire and the LE questionnaire results. The results of the factor analysis indicate that speech recognition in noise provides information highly comparable to information from speech intelligibility in quiet. Conclusions: The factor analysis highlighted three components describing the postoperative outcome of CI patients. These were (i) the audiometrically measured supra-threshold speech recognition and (ii) near-threshold audibility, as well as (iii) the subjective assessment of the relationship to real life as determined by the questionnaires. These parameters appear well suited to setting up a framework for a test battery to assess CI outcomes.

Factors impacting outcomes of cochlear implantation in children at two University centres in China: Multi-year analysis from the Paediatric Implanted Recipient Observational Study (P-IROS)

Objectives To identify factors affecting functional hearing performance and quality of life (QoL) outcomes in paediatric cochlear implantation (CI) recipients at two University centres in mainland China. Methods Two university centres in mainland China, part of the prospective longitudinal Paediatric Implanted Recipient Observational Study (P-IROS), contributed participant data. Participants were aged under 10 years at time of CI. Functional hearing performance and QoL measures were collected prior to device activation, and at 6-monthly intervals for 2 years post-implantation. Functional hearing endpoints including Categories of Auditory Performance-II (CAP-II) and QoL were evaluated and analysed using ordinal mixed-effects regression models. Results Data were from 288 children with a mean age at implant of 2.74 years. Overall follow-up at 1 year was 59% and 51% at 2 years. Younger age at implantation (p<0.001) and hearing aid use preimplantation (p=0.026) were associated with significant benefit. Bilateral device users (both CI and bimodal) achieved significantly better functional hearing performance on the CAP-II than unilateral CI users (p<0.001). Slower functional hearing improvements were observed in those with lower parental expectations compared to higher expectations (p<0.001). QoL improved over time but followed a different initial trajectory between centres. Conclusion All participants demonstrated significant improvements in auditory performance and QoL over time. Younger age at CI, and bilateral/bimodal device fitting contributed to earlier improvements. Other potential factors that could help inform families, professionals, and health authorities about choice of hearing device and educational supports required included aetiology of hearing loss and level of maternal education.

The Inter-Phase Gap Offset Effect as a Measure of Neural Health in Cochlear Implant Users With Residual Acoustic Hearing.

The inter-phase gap (IPG) offset effect is defined as the dB offset between the linear parts of electrically evoked compound action potential (ECAP) amplitude growth functions for two stimuli differing only in IPG. The method was recently suggested to represent neural health in cochlear implant (CI) users while being unaffected by CI electrode impedances. Hereby, a larger IPG offset effect should reflect better neural health. The aims of the present study were to (1) examine whether the IPG offset effect negatively correlates with the ECAP threshold and the preoperative pure-tone average (PTA) in CI recipients with residual acoustic hearing and (2) investigate the dependency of the IPG offset effect on hair cell survival and intracochlear electrode impedances. Seventeen adult study participants with residual acoustic hearing at 500 Hz undergoing CI surgery at the University Hospital of Zurich were prospectively enrolled. ECAP thresholds, IPG offset effects, electrocochleography (ECochG) responses to 500 Hz tone bursts, and monopolar electrical impedances were obtained at an apical, middle, and basal electrode set during and between 4 and 12 weeks after CI surgery. Pure-tone audiometry was conducted within 3 weeks before surgery and approximately 6 weeks after surgery. Linear mixed regression analyses and t tests were performed to assess relationships between (changes in) ECAP threshold, IPG offset, impedance, PTA, and ECochG amplitude. The IPG offset effect positively correlated with the ECAP threshold in intraoperative recordings (p < 0.001) and did not significantly correlate with the preoperative PTA (p = 0.999). The IPG offset showed a postoperative decrease for electrode sets that showed an ECochG amplitude drop. This IPG offset decrease was significantly larger than for electrode sets that showed no ECochG amplitude decrease, t(17) = 2.76, p = 0.014. Linear mixed regression analysis showed no systematic effect of electrode impedance changes on the IPG offset effect (p = 0.263) but suggested a participant-dependent effect of electrode impedance on IPG offset. The present study results did not reveal the expected relationships between the IPG offset effect and ECAP threshold values or between the IPG offset effect and preoperative acoustic hearing. Changes in electrode impedance did not exhibit a direct impact on the IPG offset effect, although this impact might be individualized among CI recipients. Overall, our findings suggest that the interpretation and application of the IPG offset effect in clinical settings should be approached with caution considering its complex relationships with other cochlear and neural health metrics.