Unilateral Cochlear Implants for Severe, Profound, or Moderate Sloping to Profound Bilateral Sensorineural Hearing Loss: A Systematic Review and Consensus Statements

Why Do Cochlear Implant Candidates Defer Surgery? A Retrospective Case-Control Study

OBJECTIVE(S)

Despite undergoing thorough cochlear implant (CI) candidacy evaluation and counseling, some patients ultimately elect against implantation. This study sought to identify patient-related and socioeconomic factors predicting CI deferral.

METHODS

A retrospective study of adult (≥18 years old) CI candidates presenting between 2007 and 2021 at a tertiary academic CI center was performed. The primary outcome was device implantation. Data collected included age, gender, hearing status, race, zip code of residence, median family income (MFI), distance traveled from the CI center, marital status, employment status, and insurance status. Multivariable binary logistic regression was performed to identify predictors of implantation.

RESULTS

A total of 200 patients qualifying for CI were included, encompassing 77 adults deferring surgery (CI-deferred) and 123 consecutive adults electing for surgery (CI-pursued). Age, gender, hearing status, insurance type, employment status, distance from the implant center, and MFI were comparable between the groups (p > 0.05). Compared to CI-pursued patients, CI-deferred patients were more likely to be non-Caucasian (24.7% vs. 9.8%, p = 0.015) and unmarried (55.8% vs. 38.2%, p = 0.015). On multivariable logistic regression, older age (OR 0.981, 0.964-0.998, p = 0.027), African American race (OR 0.227, 0.071-0.726, p = 0.012), and unmarried status (OR 0.505, 0.273-0.935, p = 0.030) were independent predictors of implant deferral.

CONCLUSION

This study demonstrates that increasing age at evaluation, African American race, and unmarried status are predictors for deferring CI surgery despite being implant candidates. These patients may benefit from increased outreach in the form of counseling, education, and social support prior to undergoing CI surgery.

LEVEL OF EVIDENCE

3 - retrospective study with internal control group Laryngoscope, 134:2857-2863, 2024.

Understanding Patient Utilization Patterns of Cochlear Implant Processors

OBJECTIVE

To evaluate the extent of benefit the second processor provides and to better understand utilization patterns regarding cochlear implant (CI) sound processors.

BACKGROUND

Institutional contracts determine the external CI sound processor hardware that a patient is eligible for. Despite the high prevalence of CI worldwide, there is a paucity in the literature regarding patient preferences and how patients utilize provided external hardware.

METHODS

A close-ended, multiple-choice survey was mailed to all patients over the age of 18 years who underwent CI between 2016 to 2020 at a tertiary academic medical center. Patients who received their CI hardware prior to 2018 were provided 2 processors, whereas those who received their hardware in 2018 or later were provided 1 processor.

RESULTS

A total of 100/263 surveys were returned for a response rate of 38.0%. Of the cohort with 1 processor, 31.3% experienced a period without a functioning processor and access to sound compared to 5.6% of the cohort with 2 processors (P = -.003). Of the cohort with 2 processors, 24.3% noted that they often or always utilize their second processor. When asked how important having a second processor was, 62.9% of the 2-processor group responded that it was very important (P = .001). The most common reason for utilizing the second processor was a damaged primary processor. Patients who received 2 processors had a significantly lower number of postoperative audiology clinic visits for device troubleshooting (P < .001).

CONCLUSION

Patients who have 2 CI external processors identify this as being very important to them and experience significantly less time without access to sound due to lack of a functioning processor. As institutional contracts often dictate whether a patient will receive 1 or 2 sound processors with their CI hardware, it is important to understand patient preferences and utilization patterns in order to guide patient-centric policies.

AI model for predicting adult cochlear implant candidacy using routine behavioral audiometry

OBJECTIVE

To describe an AI model to facilitate adult cochlear implant candidacy prediction based on basic demographical data and standard behavioral audiometry.

METHODS

A machine-learning approach using retrospective demographic and audiometric data to predict candidacy CNC word scores and AzBio sentence in quiet scores was performed at a tertiary academic center. Data for the model were derived from adults completing cochlear implant candidacy testing between January 2011 and March 2023. Comparison of the prediction model to other published prediction tools and benchmarks was performed.

RESULTS

The final dataset included 770 adults, encompassing 1045 AzBio entries, and 1373 CNC entries. Isophoneme scores and word recognition scores exhibited strongest importance to both the CNC and AzBio prediction models, followed by standard pure tone average and low-frequency pure tone average. The mean absolute difference between the predicted and actual score was 15 percentage points for AzBio sentences in quiet and 13 percentage points for CNC word scores, approximating anticipated test-retest constraints inherent to the variables incorporated into the model. Our final combined model achieved an accuracy of 87 % (sensitivity: 90 %; precision: 80 %).

CONCLUSION

We present an adaptive AI model that predicts adult cochlear implant candidacy based on routine behavioral audiometric and basic demographical data. Implementation efforts include a public-facing online prediction tool and accompanying smartphone program, an embedded notification flag in the electronic medical record to alert providers of potential candidates, and a program to retrospectively engage past patients who may be eligible for cochlear implantation based on audiogram results.

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.

Functional Hearing Preservation in Cochlear Implantation: The Miami Cocktail Effect

OBJECTIVE

To investigate if pharmacological treatment with prednisone and L-N-acetylcysteine (STE + NAC) influence functional hearing preservation in cochlear implant (CI) surgery.

STUDY DESIGNS

Preimplantation and postimplantation longitudinal case-control study.

SETTING

Tertiary referral center.

PATIENTS

Pediatric and adult recipients of CI with preimplantation functional hearing defined as an average of air-conducted thresholds at 125, 250, and 500 Hz (low-frequency pure-tone average [LFPTA]) <80 dB.

INTERVENTIONS

Preimplantation and postimplantation audiometry. Weight-adjusted oral prednisone and L-N-acetylcysteine starting 2 days before surgery (Miami cocktail). Prednisone was continued for 3 days and L-N-acetylcysteine for 12 days after surgery, respectively. Cochlear implantation with conventional length electrodes.

MAIN OUTCOME MEASURES

Proportion of patients with LFPTA <80 dB, and LFPTA change at 1-year postimplantation.

RESULTS

All 61 patients received intratympanic and intravenous dexamethasone intraoperatively, with 41 patients receiving STE + NAC and 20 patients not receiving STE + NAC. At 1-year postimplantation, the proportion of functional hearing preservation was 83% in the STE + NAC group compared with 55% of subjects who did not receive STE + NAC ( p = 0.0302). The median LFPTA change for STE + NAC-treated and not treated subjects was 8.33 dB (mean, 13.82 ± 17.4 dB) and 18.34 dB (mean, 26.5 ± 23.4 dB), respectively ( p = 0.0401, Wilcoxon rank test). Perioperative STE + NAC treatment resulted in 10 dB of LFPTA better hearing than when not receiving this treatment. Better low-frequency preimplantation hearing thresholds were predictive of postimplantation functional hearing. No serious side effects were reported.

CONCLUSION

Perioperative STE + NAC, "The Miami Cocktail," was safe and superior to intraoperative steroids alone in functional hearing preservation 1-year after cochlear implantation.

CROS or hearing aid? Selecting the ideal solution for unilateral CI patients with limited aidable hearing in the contralateral ear

A hearing aid or a contralateral routing of signal device are options for unilateral cochlear implant listeners with limited hearing in the unimplanted ear; however, it is uncertain which device provides greater benefit beyond unilateral listening alone. Eighteen unilateral cochlear implant listeners participated in this prospective, within-participants, repeated measures study. Participants were tested with the cochlear implant alone, cochlear implant + hearing aid, and cochlear implant + contralateral routing of signal device configurations with a one-month take-home period between each in-person visit. Audiograms, speech perception in noise, and lateralization were evaluated. Subjective feedback was obtained via questionnaires. Marked improvement in speech in noise and non-implanted ear lateralization accuracy were observed with the addition of a contralateral hearing aid. There were no significant differences in speech recognition between listening configurations. However, the chronic device use questionnaires and the final device selection showed a clear preference for the hearing aid in spatial awareness and communication domains. Individuals with limited hearing in their unimplanted ears demonstrate significant improvement with the addition of a contralateral device. Subjective questionnaires somewhat contrast with clinic-based outcome measures, highlighting the delicate decision-making process involved in clinically advising one device or another to maximize communication benefits.

Outcome Prediction of Speech Perception in Quiet and in Noise for Cochlear Implant Candidates Based on Pre-Operative Measures

(1) Background: The fitting of cochlear implants (CI) is an established treatment, even in cases with considerable residual hearing but insufficient speech perception. The aim of this study was to evaluate a prediction model for speech in quiet and to provide reference data and a predictive model for postoperative speech perception in noise (SPiN) after CI provision. (2) Methods: CI candidates with substantial residual hearing (either in hearing threshold or in word recognition scores) were included in a retrospective analysis (n = 87). Speech perception scores in quiet 12 months post-surgery were compared with the predicted scores. A generalized linear model was fitted to speech reception thresholds (SRTs) after CI fitting to identify predictive variables for SPiN. (3) Results: About two-thirds of the recipients achieved the expected outcome in quiet or were better than expected. The mean absolute error of the prediction was 13.5 percentage points. Age at implantation was the only predictive factor for SPiN showing a significant correlation (r = 0.354; p = 0.007). (4) Conclusions: Outcome prediction accuracy for speech in quiet was comparable to previous studies. For CI recipients in the included study population, the SPiN outcome could be predicted only based on the factor age.

A basement membrane extract-based three-dimensional culture system promotes the neuronal differentiation of cochlear Sox10-positive glial cells in vitro

Spiral ganglion neurons (SGNs) in the mammalian cochleae are essential for the delivery of acoustic information, and damage to SGNs can lead to permanent sensorineural hearing loss as SGNs are not capable of regeneration. Cochlear glial cells (GCs) might be a potential source for SGN regeneration, but the neuronal differentiation ability of GCs is limited and its properties are not clear yet. Here, we characterized the cochlear Sox10-positive (Sox10+) GCs as a neural progenitor population and developed a basement membrane extract-based three-dimensional (BME-3D) culture system to promote its neuronal generation capacity in vitro. Firstly, the purified Sox10+ GCs, isolated from Sox10-creER/tdTomato mice via flow cytometry, were able to form neurospheres after being cultured in the traditional suspension culture system, while significantly more neurospheres were found and the expression of stem cell-related genes was upregulated in the BME-3D culture group. Next, the BME-3D culture system promoted the neuronal differentiation ability of Sox10+ GCs, as evidenced by the increased number, neurite outgrowth, area of growth cones, and synapse density as well as the promoted excitability of newly induced neurons. Notably, the BME-3D culture system also intensified the reinnervation of newly generated neurons with HCs and protected the neurospheres and derived-neurons against cisplatin-induced damage. Finally, transcriptome sequencing analysis was performed to identify the characteristics of the differentiated neurons. These findings suggest that the BME-3D culture system considerably promotes the proliferation capacity and neuronal differentiation efficiency of Sox10+ GCs in vitro, thus providing a possible strategy for the SGN regeneration study.

Speech Understanding and Subjective Listening Effort in Noise With Different OTEs and Sound Processing Technologies

OBJECTIVE

To determine speech reception thresholds (SRTs) in noise and subjective listening effort (LE) in cochlear implant (CI) recipients for application of three sound processing (SP) technologies with two off-the-ear (OTE) CI sound processors, a fixed moderately directional microphone (Standard), an adaptive directional microphone (Beam), and the spatial noise-reduction setting ForwardFocus, with the Kanso 2 (OTE2), and Beam with the Kanso (OTE1).

STUDY DESIGN

Prospective repeated measures, within-subject design.

SETTING

Single tertiary-referral center.

PATIENTS

Twenty CI recipients with bilateral severe-to-profound sensorineural hearing loss.

MAIN OUTCOME MEASURES

SRTs were assessed in two spatial configurations with frontal speech and noise from 90-180-270 degrees (S0N90-180-270) or from the CI side (S0NCI). SRTs were obtained for sentences of the Oldenburg sentence test presented in International Collegium of Rehabilitative Audiology (ICRA) noise ICRA5-250. LE for speech understanding in noise was evaluated in S0N90-180-270 and assessed in effort scale categorical units (ESCUs) by using Adaptive Categorical Listening Effort Scaling (ACALES). LEs at 5-dB signal-to-noise ratio (SNR) were calculated from fitted psychometric curves.

RESULTS

With OTE2 in S0N90-180-270, SRT with ForwardFocus (-4.28 dB SNR) was better than with Beam (-3.13 dB SNR) and Standard (0.43 dB SNR). ForwardFocus showed lower LE5dB (2.61 ESCU) compared with Beam (4.60 ESCU) and Standard (5.32 ESCU). In a comparison of both OTEs in S0N90-180-270 regarding best-performing SP technology, ForwardFocus with OTE2 yielded a better SRT and better LE5dB than Beam with OTE1 (SRT: -1.70 dB SNR; LE5dB: 4.00 ESCU). With OTE2 in S0NCI, SRT was improved with ForwardFocus (-2.78 dB SNR) compared with Beam (-1.23 dB SNR) and Standard (1.83 dB SNR).

CONCLUSION

With respect to SP technology and OTE, CI recipients experience best SRT and lowest LE in S0N90-180-270 when using ForwardFocus with OTE2. ACALES is feasible for assessing subjective LE in CI recipients.

Cochlear implant referral patterns in the UK suggest a postcode lottery with inequitable access for older adults; results of a pilot audit in five Audiology sites

OBJECTIVE

To use a standardised reporting tool to identify potential eligible candidates for cochlear implant (CI) referral and quantify the proportion of adults who had a CI referral discussion after presenting with an audiogram within United Kingdom (UK) audiometric criteria.

DESIGN

Retrospective multicentre 6-month audit of Audiology clinic databases.

STUDY SAMPLE

A total of 810 adults from five geographically diverse UK Audiology sites.

RESULTS

Data were collected in late 2019 after UK CI audiometric candidacy criteria changed; one site collected only 3 months of data. The proportion of potential eligible adults (based only on audiometry) considered for CI referral was 64% (521 out of 810) and varied by site (from 50% to 83%). About 24% of patients (123 out of 521) declined CI referral; this also varied across sites (12-45%). The median age of patients where CI referral was not considered was 80 years - significantly higher than the group where CI referral was considered (73 years).

CONCLUSIONS

CI referral is dependent on where adults live, and how old they are. Older adults are significantly less likely to be considered for CI referral by Audiologists. Audiology clinics need more support to empower staff to talk to patients about CI referral.

Investigation of Maximum Monosyllabic Word Recognition as a Predictor of Speech Understanding with Cochlear Implant

Background: The cochlear implant (CI) is an established treatment option for patients with inadequate speech understanding and insufficient aided scores. Nevertheless, reliable predictive models and specific therapy goals regarding achievable speech understanding are still lacking. Method: In this retrospective study, 601 cases of CI fittings between 2005 and 2021 at the University Medical Center Freiburg were analyzed. We investigated the preoperative unaided maximum word recognition score (mWRS) as a minimum predictor for post-interventional scores at 65 dB SPL, WRS65(CI). The WRS65(CI) was compared with the preoperative-aided WRS, and a previously published prediction model for the WRS65(CI) was reviewed. Furthermore, the effect of duration of hearing loss, duration of HA fitting, and etiology on WRS65(CI) were investigated. Results: In 95.5% of the cases, a significant improvement in word recognition was observed after CI. WRS65(CI) achieved or exceeded mWRS in 97% of cases. Etiology had a significant impact on WRS65(CI). The predicted score was missed by more than 20 percentage points in 12.8% of cases. Discussion: Our results confirmed the minimum prediction via mWRS. A more precise prediction of the expected WRS65(CI) is possible. The etiology of hearing loss should be considered in the indication and postoperative care to achieve optimal results.

The Benefits of Cochlear Implantation for Adults: A Systematic Umbrella Review

OBJECTIVES

The uptake of cochlear implants among adults who could benefit (based on pure-tone audiometry) in developed countries is estimated to be less than 10%. Concerns about potential surgical complications, fear of losing residual hearing, and limited awareness about the benefits of this intervention contribute to the low adoption rate. To enhance quality of life and improve the uptake of cochlear implants, it is essential to have a clear understanding of their benefits.

DESIGN

This umbrella review aims to summarize the major benefits of cochlear implant usage in adults, by synthesizing findings from published review articles. A comprehensive search of databases including MEDLINE, EMBASE, PsycINFO, and Google Scholar, was conducted. The search was limited to English-language review articles published between 1990 and 2022, focusing on cochlear implant outcomes in at least 5 adults (aged ≥18 years). Two independent reviewers screened titles, abstracts, and full-text articles, and conducted a quality assessment using the Joanna Briggs Checklist for Systematic Reviews and Research Syntheses.

RESULTS

Forty-two articles were included in this review. There were 15 systematic reviews with meta-analysis, 25 systematic reviews without meta-analysis, and 2 systematic scoping reviews. All 42 articles underwent quality assessment using the Joanna Briggs Institute Checklist for Systematic Reviews and Research Syntheses, of which 40% (n = 17) satisfied 9 out of 11 quality criteria. This umbrella review shows that cochlear implants are associated with improvements in speech perception and recognition as well as improved quality of life and cognition. These benefits are observed in a significant proportion of adults undergoing the procedure, highlighting its effectiveness as a viable intervention for individuals with severe to profound hearing loss.

CONCLUSIONS

The potential benefits of cochlear implantation appear to outweigh the risks and complications associated with the procedure. It is recommended that adults with severe to profound hearing loss in particular, engage in informed discussions with healthcare professionals to consider cochlear implantation as a viable treatment option.

The impact of cochlear implantation on quality of life and psychological status in single-sided deafness or asymmetric hearing loss with tinnitus and influencing factors of implantation intention: a preliminary study

PURPOSE

The current study aims to explore the therapeutic effect of cochlear implants (CIs) on tinnitus in patients with single-sided deafness or asymmetric hearing loss (SSD/AHL) as well as the improvement of tinnitus-related quality of life and psychological status. In addition, we also explored whether the levels of quality of life and psychological status was related to the patient's implantation intention.

METHODS

Seven patients decided to receive cochlear implantation. Before and after implantation, they completed the Visual Analogue Scale (VAS) and the Tinnitus Questionnaire (TQ) to assess tinnitus severity, the Speech, Spatial and Qualities of Hearing Scale (SSQ), and the Medical Outcomes Study Short Form 36 Health Survey Questionnaire (SF-36) to assess the quality of life, the Simplified Coping Style Questionnaire (SCSQ) to assess psychological status. The other 8 SSD patients refused cochlear implantation. Their scores of the above questionnaires were compared with those of patients received implantation.

RESULTS

Six months after cochlear implantations, the tinnitus perception, loudness, and annoyance significantly decreased compared to that before implantation. In terms of quality of life and physiological status, no statistically significant changes were detected in SSQ, SF-36, and SCSQ measurements. The score of annoyance subcategory of VAS and all subcategories of SSQ of patients refused implantation were better than those of implanted patients before implantation.

CONCLUSIONS

These results suggest that CIs can significantly reduce tinnitus severity. Patients refused implantation had better status in the annoyance of VAS and all subcategories of SSQ scores than those received implantation.

Word Recognition with a Cochlear Implant in Relation to Prediction and Electrode Position

BACKGROUND

the word recognition score (WRS) achieved with cochlear implants (CIs) varies widely. To account for this, a predictive model was developed based on patients' age and their pre-operative WRS. This retrospective study aimed to find out whether the insertion depth of the nucleus lateral-wall electrode arrays contributes to the deviation of the CI-achieved WRS from the predicted WRS.

MATERIALS AND METHODS

patients with a pre-operative maximum WRS > 0 or a pure-tone audiogram ≥80 dB were included. The insertion depth was determined via digital volume tomography.

RESULTS

fifty-three patients met the inclusion criteria. The median WRS achieved with the CI was 70%. The comparison of pre- and post-operative scores achieved with a hearing aid and a CI respectively in the aided condition showed a median improvement of 65 percentage points (pp). A total of 90% of the patients improved by at least 20 pp. The majority of patients reached or exceeded the prediction, with a median absolute error of 11 pp. No significant correlation was found between the deviation from the predicted WRS and the insertion depth.

CONCLUSIONS

our data support a previously published model for the prediction of the WRS after cochlear implantation. For the lateral-wall electrode arrays evaluated, the insertion depth did not influence the WRS with a CI.

Strategies for the implementation of the living guidelines for cochlear implantation in adults

Introduction

Clinical guidelines for cochlear implants (CI) exist in several countries, however, they lack consistency and often do not encompass the full user journey. This study aims to explore the barriers and facilitators for implementing global Living Guidelines for cochlear implantation in adults with severe, profound or moderate sloping to profound sensorineural hearing loss (SPSNHL) as well as identify guideline implementation (GI) tools that may support uptake.

Methods

A convenience sample of Task Force members were recruited for semi-structured interviews. Interview transcripts were thematically analysed to group country-specific barriers, facilitators and GI tools into three levels: health care provider (HCP), consumer and structural. Once identified, barriers and facilitators were classified into four themes related to awareness, economic, guideline or other.

Results

Interviews were conducted with 38 Task Force members, representing 20 countries. Lack of CI and hearing loss awareness was a major barrier at the HCP (85% of countries), consumer (80%) and structural (20%) levels. Economic and guideline barriers followed at the HCP (35%; 25%), consumer (45%; 0%) and structural (55%; 30%) levels, respectively. Facilitators focused on raising awareness of hearing loss and CIs as well as guideline related initiates at the HCP (80%; 70%), consumer (70%; 10%) and structural (25%; 70%) levels. GI tools including education, economic evaluations, quick reference resources and social media can help improve awareness and uptake.

Conclusion

Awareness is the primary barrier to implementing Living Guidelines globally for adults with SPSNHL. Endorsement from key professional bodies and using the best available evidence can enhance uptake.

Factors Affecting Performance in Adults With Cochlear Implants: A Role for Cognition and Residual Cochlear Function

OBJECTIVE

To evaluate the impact of preoperative and perioperative factors on postlinguistic adult cochlear implant (CI) performance and design a multivariate prediction model.

STUDY DESIGN

Prospective cohort study.

SETTING

Tertiary referral center.

PATIENTS AND INTERVENTIONS

Two hundred thirty-nine postlinguistic adult CI recipients.

MAIN OUTCOME MEASURES

Speech-perception testing (consonant-nucleus-consonant [CNC], AzBio in noise +10-dB signal-to-noise ratio) at 3, 6, and 12 months postoperatively; electrocochleography-total response (ECochG-TR) at the round window before electrode insertion.

RESULTS

ECochG-TR strongly correlated with CNC word score at 6 months ( r = 0.71, p < 0.0001). A multivariable linear regression model including age, duration of hearing loss, angular insertion depth, and ECochG-TR did not perform significantly better than ECochG-TR alone in explaining the variability in CNC. AzBio in noise at 6 months had moderate linear correlations with Montreal Cognitive Assessment (MoCA; r = 0.38, p < 0.0001) and ECochG-TR ( r = 0.42, p < 0.0001). ECochG-TR and MoCA and their interaction explained 45.1% of the variability in AzBio in noise scores.

CONCLUSIONS

This study uses the most comprehensive data set to date to validate ECochG-TR as a measure of cochlear health as it relates to suitability for CI stimulation, and it further underlies the importance of the cochlear neural substrate as the main driver in speech perception performance. Performance in noise is more complex and requires both good residual cochlear function (ECochG-TR) and cognition (MoCA). Other demographic, audiologic, and surgical variables are poorly correlated with CI performance suggesting that these are poor surrogates for the integrity of the auditory substrate.

Improved Cochlear Implant Performance Estimation Using Tonotopic-Based Electrocochleography

Importance

Cochlear implantation produces remarkable results in postlingual deafness, although auditory outcomes vary. Electrocochleography (ECochG) has emerged as a valuable tool for assessing the cochlear-neural substrate and evaluating patient prognosis.

Objective

To assess whether ECochG-total response (ECochG-TR) recorded at the best-frequency electrode (BF-ECochG-TR) correlates more strongly with speech perception performance than ECochG-TR measured at the round window (RW-ECochG-TR).

Design, Setting, and Participants

This single-center cross-sectional study recruited 142 patients from July 1, 2021, to April 30, 2022, with 1-year follow-up. Exclusions included perilymph suctioning, crimped sound delivery tubes, non-native English speakers, inner ear malformations, nonpatent external auditory canals, or cochlear implantation revision surgery.

Exposures

Cochlear implantation.

Main Outcomes and Measures

Speech perception testing, including the consonant-nucleus-consonant (CNC) words test, AzBio sentences in quiet, and AzBio sentences in noise plus 10-dB signal to noise ratio (with low scores indicating poor performance and high scores indicating excellent performance on all tests), at 6 months postoperatively; and RW-ECochG-TR and BF-ECochG-TR (measured for 250, 500, 1000, and 2000 Hz).

Results

A total of 109 of the 142 eligible postlingual adults (mean [SD] age, 68.7 [15.8] years; 67 [61.5%] male) were included in the study. Both BF-ECochG-TR and RW-ECochG-TR were correlated with 6-month CNC scores (BF-ECochG-TR: r = 0.74; 95% CI, 0.62-0.82; RW-ECochG-TR: r = 0.67; 95% CI, 0.54-0.76). A multivariate model incorporating age, duration of hearing loss, and angular insertion depth did not outperform BF-ECochG-TR or RW-ECochG-TR alone. The BF-ECochG-TR correlation with CNC scores was significantly stronger than the RW-ECochG-TR correlation (r difference = -0.18; 95% CI, -0.31 to -0.01; z = -2.02). More moderate correlations existed between 6-month AzBio scores in noise, Montreal Cognitive Assessment (MoCA) scores (r = 0.46; 95% CI, 0.29-0.60), and BF-ECochG-TR (r = 0.42; 95% CI, 0.22-0.58). MoCA and the interaction between BF-ECochG-TR and MoCA accounted for a substantial proportion of variability in AzBio scores in noise at 6 months (R2 = 0.50; 95% CI, 0.36-0.61).

Conclusions and Relevance

In this case series, BF-ECochG-TR was identified as having a stronger correlation with cochlear implantation performance than RW-ECochG-TR, although both measures highlight the critical role of the cochlear-neural substrate on outcomes. Demographic, audiologic, and surgical factors demonstrated weak correlations with cochlear implantation performance, and performance in noise was found to require a robust cochlear-neural substrate (BF-ECochG-TR) as well as sufficient cognitive capacity (MoCA). Future cochlear implantation studies should consider these variables when assessing performance and related interventions.

The Effects of Stimulus Repetition Rate on Electrically Evoked Auditory Brainstem Potentials in Postlingually Deafened Adult Cochlear Implant Recipients

Background: By using outcome prediction scores, it is possible to distinguish between good and poor performers with cochlear implants (CI) after CI implantation. The reasons for poor performance, despite good basic conditions, can be manifold. On the one hand, the postoperative fitting may be inadequate; on the other, neurophysiological disease processes may impair speech understanding with a CI. These disease processes are not yet fully understood. In acoustics, it is known that the auditory brainstem responses (ABR) and their latencies and amplitudes allow differential diagnosis based on reference values for normal-hearing individuals. The aim of this study was to provide reference values for electrically evoked brainstem responses (EABRs) in terms of rate-dependent latencies and amplitudes. Methods: 20 ears of 18 experienced adult CI recipients with a predicted and measured good postoperative word recognition score were recruited from the clinic's patient pool. In the same stimulation mode and intensity we measured latencies and interpeak-latencies of EABRs and electrically evoked compound action potentials (ECAPs). With a defined supra-threshold stimulation intensity above the individual ECAP threshold, we applied stimulation at several rates between 11 and 91 stimuli per second. Results: We found rate dependences for EABR latency t3 and t5 in the order of 0.19 ms and 0.37 ms, respectively, while ECAP was not affected by rate. Correspondingly, the interpeak intervals' rate dependences for t5-t1, t5-t3 and t3-t1 were of the order of 0.37 ms, 0.18 ms and 0.19 ms. Comparing the EABR amplitudes between the stimulation rates 11/s and 81/s, we found that at 81/s the amplitudes were significantly reduced down: to 73% for A3 and 81% for A5. These rate dependences of latency and amplitude in EABR have characteristics comparable to those of acoustic ABR. Conclusions: These data may serve to provide reference values for EABR and ECAP latencies, interpeak intervals and amplitudes with respect to stimulation rate. Altered response patterns of ECAPs and EABRs to normalised stimulation modes could be used in the future to describe and classify neuropathological processes in a better-differentiated way.

How Can We Compare Cochlear Implant Systems across Manufacturers? A Scoping Review of Recent Literature

Electric stimulation via a cochlear implant (CI) enables people with severe-to-profound sensorineural hearing loss to regain speech understanding and music appreciation and, thus, allow them to actively engage in social life. Three main manufacturers (CochlearTM, MED-ELTM, and Advanced BionicsTM "AB") have been offering CI systems, thus challenging CI recipients and otolaryngologists with a difficult decision as currently no comprehensive overview or meta-analysis on performance outcomes following CI implantation is available. The main goals of this scoping review were to (1) map the literature on speech and music performance outcomes and to (2) find whether studies have performed outcome comparisons between devices of different manufacturers. To this end, a literature search was conducted to find studies that address speech and music outcomes in CI recipients. From a total of 1592 papers, 188 paper abstracts were analyzed and 147 articles were found suitable for an examination of full text. From these, 42 studies were included for synthesis. A total of 16 studies used the consonant-nucleus-consonant (CNC) word recognition test in quiet at 60 db SPL. We found that aside from technical comparisons, very few publications compared speech outcomes across manufacturers of CI systems. However, evidence suggests that these data are available in large CI centers in Germany and the US. Future studies should therefore leverage large data cohorts to perform such comparisons, which could provide critical evaluation criteria and assist both CI recipients and otolaryngologists to make informed performance-based decisions.

Associations Between Body Composition and Sensorineural Hearing Loss Among Adults Based on the UK Biobank

OBJECTIVE

To explore the association between body composition and sensorineural hearing loss (SNHL).

STUDY DESIGN

Cross-sectional study, prospective study and Mendelian randomization (MR) analyses.

SETTING

UK Biobank.

METHODS

This cross-sectional study included 147,296 adult participants with complete data on body composition and the speech-reception-threshold (SRT) test. We further conducted a prospective study with 129,905 participants without SNHL at baseline and followed up to 15 years to explore the association between body composition and new-onset SNHL. Multivariable logistic regression and Cox regression models were used. Subgroup analyses stratified by age and sex were performed. We further assessed the causal association between body composition and SNHL using two-sample MR analyses.

RESULTS

Our cross-sectional study revealed that fat percentage, especially leg (odds ratio [OR] 1.46, p = .029) and arm (OR 1.43, p = .004), were significant risk factors for SNHL. However, fat-free mass, especially in the arm (OR 0.27, p < .001) and leg (OR 0.58, p < .001) showed significant protective effects against SNHL, which was substantially consistent with the results of the prospective study. In addition, we found that young women with SNHL were more susceptible to body composition indicators. However, MR analyses revealed no evidence of significant causal association.

CONCLUSION

Fat percentage, especially in the leg and arm, was a significant risk factor for SNHL, whereas fat-free mass, especially in the leg and arm, had significant protective effects against SNHL, however, these associations may not be causal.

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.

The Impact of Patient Factors on Objective Cochlear Implant Verification Using Acoustic Cortical Auditory-Evoked Potentials

INTRODUCTION

Hearing loss is a major global public health issue that negatively impacts quality of life, communication, cognition, social participation, and mental health. The cochlear implant (CI) is the most efficacious treatment for severe-to-profound sensorineural hearing loss. However, variability in outcomes remains high among CI users. Our previous research demonstrated that the existing subjective methodology of CI programming does not consistently produce optimal stimulation for speech perception, thereby limiting the potential for CI users to derive the maximum device benefit to achieve their peak potential. We demonstrated the benefit of utilising the objective method of measuring auditory-evoked cortical responses to speech stimuli as a reliable tool to guide and verify CI programming and, in turn, significantly improve speech perception performance. The present study was designed to investigate the impact of patient- and device-specific factors on the application of acoustically-evoked cortical auditory-evoked potential (aCAEP) measures as an objective clinical tool to verify CI mapping in adult CI users with bilateral deafness (BD).

METHODS

aCAEP responses were elicited using binaural peripheral auditory stimulation for four speech tokens (/m/, /g/, /t/, and /s/) and recorded by HEARLab™ software in adult BD CI users. Participants were classified into groups according to subjective or objective CI mapping procedures to elicit present aCAEP responses to all four speech tokens. The impact of patient- and device-specific factors on the presence of aCAEP responses and speech perception was investigated between participant groups.

RESULTS

Participants were categorised based on the presence or absence of the P1-N1-P2 aCAEP response to speech tokens. Out of the total cohort of adult CI users (n = 132), 63 participants demonstrated present responses pre-optimisation, 37 participants exhibited present responses post-optimisation, and the remaining 32 participants either showed an absent response for at least one speech token post-optimisation or did not accept the optimised CI map adjustments. Overall, no significant correlation was shown between patient and device-specific factors and the presence of aCAEP responses or speech perception scores.

CONCLUSION

This study reinforces that aCAEP measures offer an objective, non-invasive approach to verify CI mapping, irrespective of patient or device factors. These findings further our understanding of the importance of personalised CI rehabilitation through CI mapping to minimise the degree of speech perception variation post-CI and allow all CI users to achieve maximum device benefit.

Cochlear implants and deafness: a global case study to increase policy awareness and action on an under-resourced health issue

There has been a major growth in global health networks in recent decades to address health issues including tobacco use, alcohol abuse, and maternal mortality. Most conditions that incur high costs have provoked networks of advocates working to mitigate the impact, increase investment in research, and establish campaigns. Global health networks often work simultaneously across policy, knowledge creation, and advocacy. Until recently there has been limited activity in global health networks and advocacy addressing hearing loss and deafness which has contributed to its relatively low visibility with policymakers compared to other health conditions. This discussion paper reports on a global consultation that explored the views of advocacy groups and individuals on advocacy for the management of hearing loss, and cochlear implantation (CI). It focussed on stakeholders' views of current advocacy endeavours, opportunities and barriers, and the possible development of a global advocacy network to improve access to cochlear implantation and the supporting services. The subsequent development of a global health network, the Cochlear Implant International Community of Action (CIICA) is discussed and the conditions necessary for the successful development of health networks are explored. This paper will be of interest to those wishing to understand the factors influencing the development of health networks and advocacy.

Listening efficiency in adult cochlear-implant users compared with normally-hearing controls at ecologically relevant signal-to-noise ratios

Introduction

Due to having to work with an impoverished auditory signal, cochlear-implant (CI) users may experience reduced speech intelligibility and/or increased listening effort in real-world listening situations, compared to their normally-hearing (NH) peers. These two challenges to perception may be usefully integrated in a measure of listening efficiency: conceptually, the amount of accuracy achieved for a certain amount of effort expended.

Methods

We describe a novel approach to quantifying listening efficiency based on the rate of evidence accumulation toward a correct response in a linear ballistic accumulator (LBA) model of choice decision-making. Estimation of this objective measure within a hierarchical Bayesian framework confers further benefits, including full quantification of uncertainty in parameter estimates. We applied this approach to examine the speech-in-noise performance of a group of 24 CI users (M age: 60.3, range: 20-84 years) and a group of 25 approximately age-matched NH controls (M age: 55.8, range: 20-79 years). In a laboratory experiment, participants listened to reverberant target sentences in cafeteria noise at ecologically relevant signal-to-noise ratios (SNRs) of +20, +10, and +4 dB SNR. Individual differences in cognition and self-reported listening experiences were also characterised by means of cognitive tests and hearing questionnaires.

Results

At the group level, the CI group showed much lower listening efficiency than the NH group, even in favourable acoustic conditions. At the individual level, within the CI group (but not the NH group), higher listening efficiency was associated with better cognition (i.e., working-memory and linguistic-closure) and with more positive self-reported listening experiences, both in the laboratory and in daily life.

Discussion

We argue that listening efficiency, measured using the approach described here, is: (i) conceptually well-motivated, in that it is theoretically impervious to differences in how individuals approach the speed-accuracy trade-off that is inherent to all perceptual decision making; and (ii) of practical utility, in that it is sensitive to differences in task demand, and to differences between groups, even when speech intelligibility remains at or near ceiling level. Further research is needed to explore the sensitivity and practical utility of this metric across diverse listening situations.

Cochlear implants: the effects of age on outcomes

INTRODUCTION

Cochlear implants (CIs) provide access to sound for children and adults who do not receive adequate benefit from hearing aids. Age at implantation is known to affect outcomes across the lifespan.

AREAS COVERED

The effects of age on CI outcomes are examined for infants, children, adolescents, and older adults. A variety of outcome measures are considered, including speech perception, language, cognition, and quality of life measures.

EXPERT OPINION/COMMENTARY

For those meeting candidacy criteria, CIs are beneficial at any age. In general, younger age is related to greater benefit when considering pre-lingual deafness. Other factors such as additional disabilities, may mitigate this effect. Post-lingually deafened adults demonstrate similar benefit regardless of age, though the oldest individuals (80+) may see smaller degrees of improvement from preoperative scores. Benefit can be measured in many ways, and the areas of greatest benefit may vary based on age: young children appear to see the greatest effects of age at implantation on language measures, whereas scores on cognitive measures appear to be most impacted for the oldest population. Future research should consider implantation at extreme ages (5-9 months or > 90 years), unconventional measures of CI benefit including qualitative assessments, and longitudinal designs.

Impact of Patient Frailty on Speech Recognition and Quality of Life Outcomes in Adult Cochlear Implant Users

OBJECTIVE

The process of cochlear implantation (CI) and subsequent post-cochlear implant care is extensive and can be difficult to navigate for patients considered medically frail. This study investigates potential impact of patient frailty on speech recognition and quality of life outcomes after CI.

STUDY DESIGN

Retrospective review of a prospectively maintained database.

SETTING

Tertiary cochlear implant center.

PATIENTS

Three hundred seventy adults undergoing CI for traditional bilateral hearing loss indication.

INTERVENTIONS

None.

MAIN OUTCOME MEASURES

Comparison of pre-CI to 12-month post-CI change in consonant-nucleus-consonant phoneme/words, AzBio sentences in quiet/+10SNR, and Cochlear Implant Quality of Life (CIQOL)-35 Profile domain and global scores based on degree of patient frailty as assessed using the five-factor modified frailty index and Charlson Comorbidity Index.

RESULTS

The average age at implantation was 65.4 years (±SD, 15.7; 19-94 years). Overall, there were minimal to absent and nonsignificant differences in speech recognition outcomes (consonant-nucleus-consonant phoneme/words, and AzBio sentences +10SNR) based on pre-CI patient frailty. The exception was less improvement in AzBio quiet sentence score in patients noted to be severely frail based on Charlson Comorbidity Index (57.1% vs. 35.2%, d = 0.7 [0.3, 1]). Similar findings were observed for CIQOL-35 Profile domain and global scores where no associations were found other than decreased improvement in the social domain in patients noted to be severely frail (21.7 vs. -0.3, d = 1 [0.4, 1.7]).

CONCLUSIONS

Although some differences in outcomes were noted based on cochlear implant user frailty, these were small and isolated to only a few outcome measures. Therefore, assuming the patient is medically safe for surgery, preoperative frailty should not dissuade clinicians from recommending CI.

Changes on clinical and participatory outcomes in people with severe-to-profound hearing loss after cochlear implantation: protocol of a multicentre prospective observational cohort study - Societal Merit of Intervention on Hearing Loss Evaluation (SMILE)

INTRODUCTION

Cochlear implantation (CI) is a (cost-)effective intervention for people with severe or profound hearing loss. Since its introduction experience increased and the technology evolved, leading to better results and relaxation of CI eligibility criteria. Meanwhile, with national healthcare costs increasing there is a need for evidence of healthcare technology's value. This protocol describes a study to investigate clinical and participatory outcomes after CI for the currently (expanded) eligible hearing impaired population. The study adds to the current evidence base through its multicentre design, long-term follow-up and use of participatory outcomes alongside standard clinical outcomes.

METHODS

This multicentre prospective observational cohort study will include at least 156 adult patients with severe-to-profound hearing loss, approximately evenly divided into two groups (1, ages 18-65 years and 2, age >65 years). The measurements consist of audiometry, cognition tests, listening effort tests and multiple generic and disease specific questionnaires. Questionnaires will be administered twice before CI, soon after inclusion at CI referral and shortly before CI surgery, with an annual follow-up of 3 years after CI. The Impact on Participation and Autonomy questionnaire will be used to assess participation. Generalised models (linear, logistic, Poisson) will be used. Mixed effects models will be used to investigate changes over time while exploring differences in subgroups and the influence of covariates.

ETHICS AND DISSEMINATION

The study has received ethical approval from the Medical Ethical Committee of all participating centres. The results could provide valuable insights into changes in participatory outcomes of people with severe-to-profound hearing loss after CI. Results will be disseminated through peer-reviewed journals, scientific conferences and professional and patient organisation meetings.

TRIAL REGISTRATION NUMBER

NCT05525221.

From hearing aids to cochlear implants: The journey for private patients in New Zealand

OBJECTIVES

To understand adults' journey from hearing aids to cochlear implants (CIs).

METHODS

Qualitative, exploratory design using semi-structured interviews with twelve postlingually-deafened adults.

RESULTS AND DISCUSSION

All participants reported social isolation and/or depression. 'Not hearing well enough' was the most-common motivator to seek a CI. Due to the long wait for a public CI, they opted to pay for their implant privately. Funding was the most prominent barrier identified, with most participants using their own savings. The biggest struggle was in the period 3-months post switch-on. Many participants felt progress was slow and that they should have been doing better. After this period, benefits were most noted in quiet, with environmental sounds, and in helping them become more sociable. Music and telephone use were still areas many struggled with.

CONCLUSIONS

Participants reported the CI was worth the cost, that they would recommend it to others, and would do it again. Self-motivation was the biggest facilitator to success, with hearing professionals playing an integral role throughout the entire journey. There was a large variety of subthemes reflecting the diversity and individuality of the transition.

A new paradigm of hearing loss and preservation with cochlear implants: Learnings from fundamental studies and clinical research

In 2010 Cochlear initiated a coordinated preclinical research program to identify the factors and underlying mechanisms of acoustic hearing loss following cochlear implantation and device use. At its inception the program was structured around several major hypotheses implicated in the loss of acoustic hearing. The understanding of causes evolved over the course of the program, leading to an increased appreciation of the role of the biological response in post-implant hearing loss. A systematic approach was developed which mapped the cochlear implant journey along a timeline that considers all events in an individual's hearing history. By evaluating the available data in this context, rather than by discrete hypothesis testing, causative and associated factors may be more readily detected. This approach presents opportunities for more effective research management and may aid in identifying new prospects for intervention. Many of the outcomes of the research program apply beyond preservation of acoustic hearing to factors important to overall cochlear health and considerations for future therapies.

Cochlear Implant Adult Speech Perception Outcomes: Seniors Have Similar Good Outcomes

OBJECTIVE

The primary aim was to analyze the speech perception outcomes of patients with cochlear implants 65 years and older, compared with those younger than 65 years. The secondary aim was to analyze if preoperative hearing levels, severe compared with profound, had an effect on speech perception outcomes in senior citizens.

STUDY DESIGN

Retrospective case review of 785 patients, between 2009 and 2016.

SETTING

A large cochlear implant program.

PATIENTS

Cochlear implant adult recipients younger than 65 years and 65 years and older at the time of surgery.

INTERVENTIONS

Therapeutic-cochlear implant.

MAIN OUTCOME MEASURES

Speech perception outcomes, using City University of New York (CUNY) sentences and Consonant-Nucleus-Consonant (CNC) words. Outcomes were measured preoperatively and postoperatively at 3, 6and 12 months for cohorts younger than 65 years and 65 years and older.

RESULTS

Adult recipients younger than 65 years compared with those 65 years and older had comparable outcomes for CUNY sentence scores outcomes (p = 0.11) and CNC word scores (p = 0.69). The preoperative four-frequency average severe hearing loss (HL) cohort was significantly better compared with the profound HL cohort, for both the CUNY sentence scores (p < 0.001) and CNC word scores (p < 0.0001). The four-frequency average severe HL cohort had better outcomes irrespective of age.

CONCLUSIONS

Senior citizens have similarly good speech perception outcomes as adults younger than 65 years. Those with preoperative severe HL have better outcomes than profound loss. These finds are reassuring and can be used when counseling older cochlear implant candidates.

Multifunctional Self-Assembled Peptide Hydrogels for Biomedical Applications

Self-assembly is a growth mechanism in nature to apply local interactions forming a minimum energy structure. Currently, self-assembled materials are considered for biomedical applications due to their pleasant features, including scalability, versatility, simplicity, and inexpensiveness. Self-assembled peptides can be applied to design and fabricate different structures, such as micelles, hydrogels, and vesicles, by diverse physical interactions between specific building blocks. Among them, bioactivity, biocompatibility, and biodegradability of peptide hydrogels have introduced them as versatile platforms in biomedical applications, such as drug delivery, tissue engineering, biosensing, and treating different diseases. Moreover, peptides are capable of mimicking the microenvironment of natural tissues and responding to internal and external stimuli for triggered drug release. In the current review, the unique characteristics of peptide hydrogels and recent advances in their design, fabrication, as well as chemical, physical, and biological properties are presented. Additionally, recent developments of these biomaterials are discussed with a particular focus on their biomedical applications in targeted drug delivery and gene delivery, stem cell therapy, cancer therapy and immune regulation, bioimaging, and regenerative medicine.

On closed-loop brain stimulation systems for improving the quality of life of patients with neurological disorders

Emerging brain technologies have significantly transformed human life in recent decades. For instance, the closed-loop brain-computer interface (BCI) is an advanced software-hardware system that interprets electrical signals from neurons, allowing communication with and control of the environment. The system then transmits these signals as controlled commands and provides feedback to the brain to execute specific tasks. This paper analyzes and presents the latest research on closed-loop BCI that utilizes electric/magnetic stimulation, optogenetic, and sonogenetic techniques. These techniques have demonstrated great potential in improving the quality of life for patients suffering from neurodegenerative or psychiatric diseases. We provide a comprehensive and systematic review of research on the modalities of closed-loop BCI in recent decades. To achieve this, the authors used a set of defined criteria to shortlist studies from well-known research databases into categories of brain stimulation techniques. These categories include deep brain stimulation, transcranial magnetic stimulation, transcranial direct-current stimulation, transcranial alternating-current stimulation, and optogenetics. These techniques have been useful in treating a wide range of disorders, such as Alzheimer's and Parkinson's disease, dementia, and depression. In total, 76 studies were shortlisted and analyzed to illustrate how closed-loop BCI can considerably improve, enhance, and restore specific brain functions. The analysis revealed that literature in the area has not adequately covered closed-loop BCI in the context of cognitive neural prosthetics and implanted neural devices. However, the authors demonstrate that the applications of closed-loop BCI are highly beneficial, and the technology is continually evolving to improve the lives of individuals with various ailments, including those with sensory-motor issues or cognitive deficiencies. By utilizing emerging techniques of stimulation, closed-loop BCI can safely improve patients' cognitive and affective skills, resulting in better healthcare outcomes.

Cochlear Implantation in Patients With Known Cognitive Impairment: What Are the Benefits?

OBJECTIVE

To evaluate the outcomes of cochlear implantation (CI) in adults with preoperatively diagnosed cognitive impairment.

STUDY DESIGN

Retrospective cohort study.

SETTING

Tertiary-care academic center.

PATIENTS

Adults undergoing CI with preexisting cognitive impairment.

INTERVENTIONS

Cochlear implantation.

MAIN OUTCOME MEASURES

1) Hearing improvement after CI; 2) morbidity and mortality associated with surgery.

RESULTS

Eight patients met inclusion criteria with mean age 77.8 years (SD, 9.6 y) at time of implantation; 7 were included in subsequent analysis as one did not have speech recognition scores. Average preoperative MoCA cognitive score of 22.6 (SD, 3.9, ≤25 demonstrates cognitive impairment). Average follow-up was 29.0 months (SD, 33.3 mo). Two patients passed away at an average 58.0 months (SD, 31.1 mo) after surgery. Median preoperative pure tone average was 86.3 dB HL ( interquartile range 31.3 dB HL) compared with 33.8 dB HL (IQR 5.0 dB HL) postoperatively ( p = <0.001). Median preoperative speech testing score (AzBio/HINT) was 21% (IQR, 24%) compared with 44% (IQR, 21%) postoperatively ( p = <0.001). There were no observed surgical complications during the follow-up period.

CONCLUSIONS

This study demonstrates that patients with cognitive impairment before CI can experience improved hearing, no increased risk of complications, and good longevity after CI. Further prospective studies are needed to further define the utility of CI in patients with impaired cognition.

Evolution of the candidacy requirements and patient perioperative assessment protocols for cochlear implantation

Cochlear implantation as an approved clinical therapy ushered in an exciting era of innovation for the treatment of hearing loss. The U.S. Food and Drug Administration approved the use of cochlear implants as a treatment option for adults with profound sensorineural hearing loss in 1985. The landscape for treating adults and children with significant hearing loss has changed dramatically over the last three decades. The purpose of this paper is to examine the evolving regulatory process and changes to clinical care. A significant emerging trend in cochlear implantation is the consideration of steroids to preserve hearing during and following surgery. This parallels the quest for hearing preservation in noise-induced hearing disorders, especially considering the current interest in biological drug therapies in this population. The future will likely usher in an era of combination therapeutics utilizing drugs and cochlear implantation. For over 30+ years and following regulatory compliance, the Rocky Mountain Ear Center has developed an extensive candidacy and outcome assessment protocol. This systematic approach evaluates both unaided and aided auditory performance during candidacy stages and post-implantation. Adjunctive measures of cognition and quality-of-life augment the auditory assessment in specific populations. Practical insights into lessons learned have directed further clinical research and have resulted in beneficial changes to clinical care.

Association of Baseline Frailty Status and Age With Postoperative Complications After Cochlear Implantation: A National Inpatient Sample Study

OBJECTIVE

To conduct a national registry-based evaluation of the independent associations of chronological age and frailty, as measured by 5- and 11-factor modified frailty index (mFI-5, mFI-11) score, on postoperative outcomes of participants undergoing cochlear implantation (CI).

STUDY DESIGN

Cross-sectional analysis.

SETTING

Multicenter national database.

PARTICIPANTS

Adults 18 years or older who underwent CI during 2001 to 2018.

MAIN OUTCOME MEASURES

Any postoperative complications (determined as the presence of major, minor, or implant-specific), extended hospital length of stay (eLOS) (≥75th percentile of study population), and nonhome discharge destination.

RESULTS

There were 5,130 participants included with a median age of 60 years (interquartile range, 44-73 y) and slight female predominance (53.5%). Under mFI-5 scoring, there were 2,979 (58.1%) robust (mFI-5 = 0), 1710 (33.3%) prefrail (mFI-5 = 1), 362 (7.1%) frail (mFI-5 = 2), and 78 (1.5%) severely frail (mFI-5 ≥ 3) participants. Three hundred twenty-eight (6.49%) participants experienced a postoperative complication, with 320 (6.2%) discharged to a nonhome destination. Multivariate analysis showed no statistically significant correlation between increasing participant age or frailty status and postoperative complications; however, increasing baseline frailty tier showed an independent association with risk of eLOS (severely frail: odds ratio, 4..83; 95% confidence interval, 3.00-7.75; p < 0.001) and nonhome discharge (severely frail: odds ratio, 6.51; 95% confidence interval, 3.81-11.11; p < 0.001). The mFI-11 showed very similar trends.

CONCLUSION

Among those evaluated, this study demonstrates that CI is a low-risk procedure in participants of all ages. Increasing frailty does not predispose to postoperative complications. However, frail patients are at additional risk for an eLOS and nonhome discharge. Short follow-up time, hospital-coding errors, and selection bias of more robust patients may limit the true results of this study.

Acoustic Change Complex Recorded in Hybrid Cochlear Implant Users

INTRODUCTION

Expanding cochlear implant (CI) candidacy criteria and advances in electrode arrays and soft surgical techniques have increased the number of CI recipients who have residual low-frequency hearing. Objective measures such as obligatory cortical auditory-evoked potentials (CAEPs) may help clinicians make more tailored recommendations to recipients regarding optimal listening mode. As a step toward this goal, this study investigated how CAEPs measured from hybrid CI users differ in two listening modes: acoustic alone (A-alone) versus acoustic plus electric (A + E).

METHODS

Eight successful hybrid CI users participated in this study. Two CAEPs, the P1-N1-P2 and the acoustic change complex (ACC), were measured simultaneously in response to the onset and change of a series of different and spectrally complex acoustic signals, in each of the two listening modes (A-alone and A + E). We examined the effects of listening mode and stimulus type on the onset and ACC N1-P2 amplitudes and peak latencies.

RESULTS

ACC amplitudes in hybrid CI users significantly differed as a function of listening mode and stimulus type. ACC responses in A + E were larger than those in the A-alone mode. This was most evident for stimuli involving a change from low to high frequency.

CONCLUSIONS

Results of this study showed that the ACC varies as a function of listening mode and stimulus type. This finding suggests that the ACC can be used as a physiologic, objective measure of the benefit of hybrid CIs, potentially supporting clinicians in making clinical recommendations on individualized listening mode, or to document subjective preference for a given listening mode. Further research into this potential clinical application in a range of hybrid recipients and/or long electrode users who have residual low-frequency hearing is warranted.

A convolutional neural network-based framework for analysis and assessment of non-linguistic sound classification and enhancement for normal hearing and cochlear implant listeners

Naturalistic sounds encode salient acoustic content that provides situational context or subject/system properties essential for acoustic awareness, autonomy, safety, and improved quality of life for individuals with sensorineural hearing loss. Cochlear implants (CIs) are an assistive hearing device that restores auditory function in hearing impaired individuals. Most CI research advancements have focused on improving speech recognition in noisy, reverberant, or time-varying diverse environments. Relatively few studies have explored non-linguistic sound (NLS) perception among CIs, and those that have carried out such studies generally reported poor perception, suggesting a clear deficit in current CI sound processing systems. In this study, a convolutional neural network (CNN)-based NLS classification model is used as a framework to compare unprocessed and CI-simulated NLS classification and evaluate NLS perception targeted algorithms among CI listeners. Additionally, a NLS enhancement algorithm that focuses on improving identifiability and perception among CI listeners is proposed. The proposed NLS enhancement algorithm is evaluated based on identifiability performance using the CI-simulated NLS classification model. The proposed NLS classification framework was able to achieve near human-level performance with no significant effect of classification modality (model vs human subject) and achieved mean classification scores of 85.86% for NH (p = 0.3758) and 65.25% for CI (p = 0.1725). Among the four different feature-based methods of the proposed NLS enhancement algorithm, the "harmonicity"-based one achieved highest mean classification accuracy of 63.75%, when compared to baseline, and demonstrated significant improvement in performance (p = 0.0403). The resulting proposed comparative NLS classification framework contributes toward (i) advancement of NLS recognition studies, (ii) mitigation of CI user recruitment constraints and listener evaluation with NH listeners, (iii) development of a community shared testbed for comparative NLS studies, and (iv) advancement of NLS enhancement studies (identifiability and perceptual factors) among CI listeners.

Comparing the Outcomes of a Personalized Versus Nonpersonalized Home-Based Auditory Training Program for Cochlear Implant Users

OBJECTIVES

Audiological rehabilitation includes sensory management, auditory training (AT), and counseling and can alleviate the negative consequences associated with (untreated) hearing impairment. AT aims at improving auditory skills through structured analytical (bottom-up) or synthetic (top-down) listening exercises. The evidence for AT to improve auditory outcomes of postlingually deafened adults with a cochlear implant (CI) remains a point of debate due to the relatively limited number of studies and methodological shortcomings. There is a general agreement that more rigorous scientific study designs are needed to determine the effectiveness, generalization, and consolidation of AT for CI users. The present study aimed to investigate the effectiveness of a personalized AT program compared to a nonpersonalized Active Control program with adult CI users in a stratified randomized controlled clinical trial.

DESIGN

Off-task outcomes were sentence understanding in noise, executive functioning, and health-related quality of life. Participants were tested before and after 16 weeks of training and after a further 8 months without training. Participant expectations of the training program were assessed before the start of training.

RESULTS

The personalized and nonpersonalized AT programs yielded similar results. Significant on-task improvements were observed. Moreover, AT generalized to improved speech understanding in noise for both programs. Half of the CI users reached a clinically relevant improvement in speech understanding in noise of at least 2 dB SNR post-training. These improvements were maintained 8 months after completion of the training. In addition, a significant improvement in quality of life was observed for participants in both treatment groups. Adherence to the training programs was high, and both programs were considered user-friendly.

CONCLUSIONS

Training in both treatments yielded similar results. For half of the CI users, AT transferred to better performance with generalization of learning for speech understanding in noise and quality of life. Our study supports the previous findings that AT can be beneficial for some CI users.

Can cochlear implantation prevent cognitive decline in the long-term follow-up?

Cognitive function and hearing are known to both decline in older adults. As hearing loss is proposed to be one modifiable risk factor for dementia, the impact of auditory rehabilitation on cognitive decline has been gaining increasing attention. Despite a large number of studies, long-term data are still rare. In a large prospective longitudinal monocentric study, 50 adults (aged ≥ 50 years) with severe postlingual bilateral hearing loss received a cochlear implant (CI). They underwent comprehensive neurocognitive testing prior to implantation (T1), at 12 months (T2) and up to 65 months (T3) after implantation. Various cognitive subdomains such as attention, inhibition, working memory, verbal fluency, mental flexibility and (delayed) recall were assessed by the computer-based non-auditory test battery ALAcog^©. The observed trajectories of two exemplary cognitive subdomains (delayed recall and working memory) were then fitted over time using multilevel growth models to adjust for sociodemographic covariates and compared with 5-year longitudinal data from a sample of older adults from the representative Survey of Health, Aging and Retirement in Europe (SHARE) study. Postoperatively, auditory functions improved from 6.98% (SD 12.83) to 57.29% (SD 20.18) in monosyllabic speech understanding. Cognitive functions significantly increased from T1 to T3 in attention (p = 0.001), delayed recall (p = 0.001), working memory (OSPAN; p = 0.001), verbal fluency (p = 0.004), and inhibition (p = 0.002). A closer look at follow-up revealed that cognitive improvement could be detected between T1 and T2 and thereafter remained stable in all subtests (p ≥ 0.06). Additional longitudinal analysis confirmed these findings in a rigorous multilevel approach in two exemplary cognitive subdomains. In contrast to the SHARE data, there was no evidence for age-differential associations over time in CI recipients. This suggests that older adults benefit equally from cochlear implantation. CI users with worse preoperative cognitive skills experienced the most benefit (p < 0.0001). Auditory rehabilitation by cochlear implantation has a stimulating effect on cognitive functions beyond an improvement in speech understanding and an increased well-being. Large multicenter studies using standardized protocols have to be undertaken in the future to find out whether hearing restoration might help to prevent cognitive decline.

Genetic Mechanism Study of Auditory Phoenix Spheres and Transcription Factors Prediction for Direct Reprogramming by Bioinformatics

Background: Hearing loss is the most common irreversible sensory disorder. By delivering regenerative cells into the cochlea, cell-based therapy provides a novel strategy for hearing restoration. Recently, newly-identified phoenix cells have drawn attention due to their nearly unlimited self-renewal and neural differentiation capabilities. They are a promising cell source for cell therapy and a potential substitute for induced pluripotent stem cells (iPSCs) in many in vitro applications. However, the underlying genomic mechanism of their self-renewal capabilities is largely unknown. The aim of this study was to identify hub genes and potential molecular mechanisms between differentiated and undifferentiated phoenix cells and predict transcription factors (TFs) for direct reprogramming. Material and Methods: The datasets were downloaded from the ArrayExpress database. Samples of differentiated and undifferentiated phoenix cells with three biological replicates were utilised for bioinformatic analysis. Differentially expressed genes (DEGs) were screened and the Gene Ontology (GO) terms and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment were investigated. The gene set enrichment analysis (GSEA) was conducted to verify the enrichment of four self-defined gene set collections, followed by protein-protein interaction (PPI) network construction and subcluster analysis. The prediction of TFs for direct reprogramming was performed based on the TRANSFAC database. Results: Ten hub genes were identified to be the key candidates for self-renewal. Ten TFs were predicted as the direct reprogramming factors. This study provides a theoretical foundation for understanding phoenix cells and clues for direct reprogramming, which would stimulate further experiments and clinical applications in hearing research and treatment.

Effect of Electrode Insertion Angle on Cochlear Implantation Outcomes in Adult and Children Patients with Sensorineural Hearing Loss

Purpose

To determine the role played by electrode insertion angle in cochlear implantation (CI) outcomes in adult and children patients with sensorineural hearing loss (SNHL).

Methods

Adults (n = 10) and children (n = 19) with SNHL undergoing CI in a tertiary specialized hospital were retrospectively enrolled. The measurements were evaluated before and after CI surgery using sound field audiometry and speech recognition tests. Questionnaires were used to assess subjective benefits. Electrode insertion angles were determined using postoperative X-rays.

Results

Both adult and children patients showed significant improvements in hearing, speech performance, and audiology and speech-related quality of life after CI. The angular insertion depths of adult and children group were 323.70 ± 43.57° and 341.53 ± 57.07°, respectively, showing no significant difference. In the adult group, deeper insertion depths were found to be strongly linked to lower postoperative pure tone thresholds at 12 months and higher postoperative disyllabic Word Recognition and Sentence Recognition Scores at 6 months (all P < 0.05). In the children group, deeper insertion depth had a positive correlation with postoperative monosyllabic Word Recognition Scores 6 and 12 months after CI surgery (both P < 0.05). Multiple linear regression models were constructed to predict disyllabic Word Recognition Scores at 6 and 12 months postoperatively in the children group, in which insertion angle, duration of hearing loss, and preoperative questionnaire result were identified as dependent variables.

Conclusions

Greater angular insertion depths resulted in improved hearing and speech performances after CI. The benefits of greater angular insertion depths can be found in both adult and children patients and last for at least 12 months. Clinicians are expected to determine the optimal implantation direction during CI and ensure the insertion depth to improve the speech rehabilitation of patients.

Guidelines for Best Practice in the Audiological Management of Adults Using Bimodal Hearing Configurations

Clinics are treating a growing number of patients with greater amounts of residual hearing. These patients often benefit from a bimodal hearing configuration in which acoustic input from a hearing aid on 1 ear is combined with electrical stimulation from a cochlear implant on the other ear. The current guidelines aim to review the literature and provide best practice recommendations for the evaluation and treatment of individuals with bilateral sensorineural hearing loss who may benefit from bimodal hearing configurations. Specifically, the guidelines review: benefits of bimodal listening, preoperative and postoperative cochlear implant evaluation and programming, bimodal hearing aid fitting, contralateral routing of signal considerations, bimodal treatment for tinnitus, and aural rehabilitation recommendations.

Current Estimates of Cochlear Implant Utilization in the United States

OBJECTIVE

To present key data from a private marketing report that characterizes U.S. cochlear implant (CI) utilization, potential CI candidate and recipient population sizes, and CI market growth.

PATIENTS

Individuals who may benefit from CI and CI recipients in the United States.

INTERVENTIONS

Cochlear implantation.

MAIN OUTCOME MEASURES

CI utilization, potential CI candidate and recipient population sizes, and CI market size and value.

RESULTS

As of 2015, a cumulative 170,252 people (240,056 devices) had undergone cochlear implantation in the United States. In the year 2015, approximately 30% of devices were implanted in bilateral CI patients, through simultaneous or sequential implantation. When considering traditional audiometric CI candidacy criteria (patients with severe to profound sensorineural hearing loss in the better hearing ear), utilization rates among the population who may benefit from CI approximated 12.7%. When considering expanded criteria including individuals with single-sided deafness or asymmetrical hearing loss (severe to profound hearing loss in the worse hearing ear), utilization rates approximated 2.1%. In 2015, there was a net increase of 20,093 individuals who may have benefited from CI who had not undergone CI, adding to the group of about 1.3 M untreated audiometric CI candidates who existed prior to that year. The CI market was valued at $450.8 M in 2015, with an average device selling price of $25,701 per device.

CONCLUSIONS

CI utilization rates remain low among individuals who meet audiometric criteria for CI. Although the annual proportion of CI recipients to new audiometric candidates has increased, the total population of untreated audiometric CI candidates continues to rise.

Comparison of Speech Test Outcomes After Cochlear Implantation in Patients With and Without Asymmetric Hearing Loss

OBJECTIVES

Determine whether asymmetric hearing loss (AHL) affects postoperative speech outcomes in cochlear implant (CI) patients.

STUDY DESIGN

Retrospective cohort study.

SETTING

Tertiary care hospital.

PATIENTS

Adult English-speaking patients with unilateral CIs implanted between 2014 and 2018 were stratified into NonAHL and AHL groups based on preoperative AzBio scores in quiet from the nonimplanted ear (0-50% vs. 51-100%, respectively).

INTERVENTIONS

CI surgery in the poorer performing ear.

MAIN OUTCOME MEASURES

Postoperative consonant-nucleusconsonant (CNC) word and AzBio sentence test scores in quiet and/or noise at +5 dB signal-to-noise ratio (SNR).

RESULTS

Of 512 patients, 33 non-AHL and 27 AHL patients were included. Average ages were 65.6 and 63.6 years, respectively. As expected, preoperative AzBio scores in quiet from the nonimplanted ear were higher in the AHL group (95% confidence interval [95%CI]: 66.4-76.4%) than the non-AHL group at baseline (95%CI: 12.3-23.6%). In both cohorts, AzBio scores in quiet from the implanted ear improved from baseline, with 24-month scores (95%CI: 73.8 - 84.9%) being higher than preoperative scores (95%CI: 13.2-23.1%). There were also significant differences in AzBio scores in quiet between cohorts overall (p  = 0.0120) on mixed model analysis, with the AHL group performing ∼6.4% better than the non-AHL group; however, differences were not significant when scores were stratified by time. In addition, there were no significant differences in CNC in quiet and AzBio scores in noise at +5 dB SNR between cohorts (p  = 0.1786 and p  = 0.6215, respectively).

CONCLUSIONS

After CI, patients with AHL can achieve scores on word and sentence tests at least comparable to traditional CI candidates, supporting the expansion of CI candidacy to include patients with AHL.

Ecological Momentary Assessment to Obtain Signal Processing Technology Preference in Cochlear Implant Users

Background: To assess the performance of cochlear implant users, speech comprehension benefits are generally measured in controlled sound room environments of the laboratory. For field-based assessment of preference, questionnaires are generally used. Since questionnaires are typically administered at the end of an experimental period, they can be inaccurate due to retrospective recall. An alternative known as ecological momentary assessment (EMA) has begun to be used for clinical research. The objective of this study was to determine the feasibility of using EMA to obtain in-the-moment responses from cochlear implant users describing their technology preference in specific acoustic listening situations. Methods: Over a two-week period, eleven adult cochlear implant users compared two listening programs containing different sound processing technologies during everyday take-home use. Their task was to compare and vote for their preferred program. Results: A total of 205 votes were collected from acoustic environments that were classified into six listening scenes. The analysis yielded different patterns of voting among the subjects. Two subjects had a consistent preference for one sound processing technology across all acoustic scenes, three subjects changed their preference based on the acoustic scene, and six subjects had no conclusive preference for either technology. Conclusion: Results show that EMA is suitable for quantifying real-world self-reported preference, showing inter-subject variability in different listening environments. However, there is uncertainty that patients will not provide sufficient spontaneous feedback. One improvement for future research is a participant forced prompt to improve response rates.

Is the clinical head impulse test helpful in cochlear implantation candidacy evaluation?

Objective

Vestibular dysfunction is a known risk of cochlear implantation (CI). However, the utility of the physical exam to screen CI candidates for vestibular dysfunction is not well-studied. The objective of this study is to evaluate the preoperative role of the clinical head impulse test (cHIT) in subjects undergoing CI surgery evaluation.

Study Design Setting and Subjects

We conducted a retrospective review of 64 adult CI candidacy cases between 2017 and 2020 at a tertiary health care center.

Methods

All patients underwent audiometric testing and evaluation by the senior author. Patients with an abnormal catch-up saccade contralateral to their worse hearing ear during cHIT were referred for formal vestibular testing. Outcomes included clinical and formal vestibular results, operated ear with regard to audiometric and vestibular results, and postoperative vertigo.

Results

Among all CI candidates, 44% (n = 28) reported preoperative disequilibrium symptoms. Overall, 62% (n = 40) of the cHITs were normal, 33% (n = 21) were abnormal, and 5% (n = 3) were inconclusive. There was one patient who presented with a false positive cHIT. Among the patients who endorsed disequilibrium, 43% had a positive preoperative cHIT. Fourteen percent of the subjects (n = 9) without disequilibrium had an abnormal cHIT. In this cohort, bilateral vestibular impairment (71%) was more common than unilateral vestibular impairment (29%). In 3% of the cases (n = 2), surgical management was revisited or altered due to cHIT findings.

Conclusion

There is a high prevalence of vestibular hypofunction in the CI candidate population. Self-reported assessments of vestibular function are often not congruent with cHIT results. Clinicians should consider incorporating cHITs as part of the preoperative physical exam to potentially avoid bilateral vestibular dysfunction in a minority of patients.

Perspectives on Support Material for Referrals to Cochlear Implantation Teams

PURPOSE

This study used a collaborative approach to explore the needs, barriers, and facilitators to developing cochlear implant referral information material that would be valuable for hard of hearing adults and referring audiologists.

METHOD

During the development of a prototype referral aid to be used within the Australian context, a multistage qualitative study was conducted using a consultative process, informal and semistructured interviews, as well as online surveys. A deductive directed content analysis approach was applied to assess respondents' perspectives. A total of 106 participants (37 hard of hearing adults and 69 audiologists) were involved across the multiple phases of this study.

RESULTS

Referral practices for the evaluation of cochlear implantation candidacy in Australia are highly inconsistent, supporting the need to streamline referral information. The following facilitators were identified to support the development of referral material: appropriate content, perceived patient benefit, and objectivity. Areas for improvement related to the broadness of the content, impact on professional identity, and accessibility.

CONCLUSIONS

Practical insight from patients and referrers can inform the development of patient-facing material related to cochlear implant referrals. Streamlining information used in educational material could alleviate confusion inherent to varied health literacy levels and support patients in making informed decisions related to pursuing, or not, cochlear implantation candidacy evaluation services.

Shikonin Attenuates Cochlear Spiral Ganglion Neuron Degeneration by Activating Nrf2-ARE Signaling Pathway

The molecular mechanisms that regulate the proliferation and differentiation of inner ear spiral ganglion cells (SGCs) remain largely unknown. Shikonin (a naphthoquinone pigment isolated from the traditional Chinese herbal medicine comfrey root) has anti-oxidation, anti-apoptosis and promoting proliferation and differentiation effects on neural progenitor cells. To study the protective effect of shikonin on auditory nerve damage, we isolated spiral ganglion neuron cells (SGNs) and spiral ganglion Schwann cells (SGSs) that provide nutrients in vitro and pretreated them with shikonin. We found that shikonin can reduce ouabain, a drug that can selectively destroy SGNs and induce auditory nerve damage, caused SGNs proliferation decreased, neurite outgrowth inhibition, cells apoptosis and mitochondrial depolarization. In addition, we found that shikonin can increase the expression of Nrf2 and its downstream molecules HO-1 and NQO1, thereby enhancing the antioxidant capacity of SGNs and SGSs, promoting cells proliferation, and inhibiting cells apoptosis by activating the Nrf2/antioxidant response elements (ARE) signal pathway. However, knockdown of Nrf2 rescued the protective effect of shikonin on SGNs and SGSs damage. In addition, we injected shikonin pretreatment into mouse that ouabain-induced hearing loss and found that shikonin pretreatment has a defensive effect on auditory nerve damage. In summary, the results of this study indicate that shikonin could attenuate the level of oxidative stress in SGNs and SGSs through the Nrf2-ARE signaling pathway activated, induce the proliferation and differentiation of SGNs, and thereby improve the neurological hearing damage in mice. Therefore, shikonin may be a candidate therapeutic drug for endogenous antioxidants that can be used to treat neurological deafness.

Review of Speech Outcomes in Cochlear Implant Recipients at a Nascent Cochlear Implant Program

Introduction: The use of cochlear implantation to rehabilitate moderate to profound sensorineural hearing loss has become more widespread; however, the adult utilization rate of cochlear implant candidates is still very less. The study aims to examine the percentage of adult patients in a heterogeneous group of cochlear implant recipients at a nascent cochlear implant program who demonstrate improvements in speech outcomes.

Methods: Speech outcome scores were assessed preoperatively and postoperatively at three, six, and 12-month intervals using consonant-nucleus-consonant (CNC) words and AzBio sentences in quiet. Mean speech outcome scores at each time point and binomial distribution tables with 95% CI were used to assess individual improvement in speech understanding.

Results: 45 patients underwent a total of 49 cochlear implantation surgeries. The mean age at surgery was 62 years. The mean preoperative CNC score in the ear to be implanted was 18%±18, while the mean postoperative CNC score at three, six, and 12 months was 35%±21, 44%±23, and 45%±25, respectively. The mean preoperative AzBio score in the ear to be implanted was 22%±26 while the mean postoperative AzBio score at three, six, and 12 months was 50%±29, 56%±27, and 63%±26, respectively. Of the implantations, 74% (32 of 43) and 69% (22 of 32) showed significant improvement at six months or one year using AzBio and CNC binomial distribution tables, respectively.

Conclusions: Findings demonstrate significant improvements in speech perception following cochlear implantation for patients not benefiting from hearing aid aural rehabilitation. The study provides realistic expectations for new and emerging programs hoping to demonstrate cochlear implant utility for improving patients’ speech outcomes.