Single Sided Deaf Cochlear Implant Users in the Difficult Listening Situation: Speech Perception and Subjective Benefit

The temporal mismatch across listening sides affects cortical auditory evoked responses in normal hearing listeners and cochlear implant users with contralateral acoustic hearing

Combining a cochlear implant with contralateral acoustic hearing typically enhances speech understanding, although this improvement varies among CI users and can lead to an interference effect. This variability may be associated with the effectiveness of the integration between electric and acoustic stimulation, which might be affected by the temporal mismatch between the two listening sides. Finding methods to compensate for the temporal mismatch might contribute to the optimal adjustment of bimodal devices and to improve hearing in CI users with contralateral acoustic hearing. The current study investigates cortical auditory evoked potentials (CAEPs) in normal hearing listeners (NH) and CI users with contralateral acoustic hearing. In NH, the amplitude of the N1 peak and the maximum phase locking value (PLV) were analyzed under monaural, binaural, and binaural temporally mismatched conditions. In CI users, CAEPs were measured when listening with CI only (CIS_only), acoustically only (AS_only) and with both sides together (CIS+AS). When listening with CIS+AS, various interaural delays were introduced between the electric and acoustic stimuli. In NH listeners, interaural temporal mismatch resulted in decreased N1 amplitude and PLV. Moreover, PLV is suggested as a more sensitive measure to investigate the integration of information between the two listening sides. CI users showed varied N1 latencies between the AS_only and CIS_only listening conditions, with increased N1 amplitude when the temporal mismatch was compensated. A tendency towards increased PLV was also observed, however, to a lesser extent than in NH listeners, suggesting a limited integration between electric and acoustic stimulation. This work highlights the potential of CAEPs measurement to investigate cortical processing of the information between two listening sides in NH and bimodal CI users.

Masked Speech Perception with Bone Conduction Device, Contralateral Routing of Signals Hearing Aid, and Cochlear Implant Use in Adults with Single-Sided Deafness: A Prospective Hearing Device Comparison using a Unified Testing Framework

INTRODUCTION

For the treatment of single-sided deafness (SSD), common treatment choices include a contralateral routing of signals (CROS) hearing aid, a bone conduction device (BCD), and a cochlear implant (CI). The primary aim of this study was to compare speech understanding in noise and binaural benefits in adults with postlingual SSD between preoperative unaided baseline, preoperative CROS and BCD trial devices, and CI, following recommendations from a consensus protocol. In addition, we investigated the effect of masker type on speech understanding.

METHODS

This was a prospective study with twelve participants. Binaural effects of head shadow, squelch, summation, and spatial release from masking were assessed by measuring speech reception thresholds (SRTs) in five different spatial target-masker configurations using two different maskers: two-talker babble (TTB), and speech-shaped noise (SSN). Preoperatively, participants were assessed unaided and with CROS and BCD trial devices. After cochlear implantation, participants were assessed at 1, 3, and 6 months post-activation.

RESULTS

For TTB, significant improvements in SRT with a CI relative to preoperatively unaided were found in all spatial configurations. With CI at 6 months, median benefits were 7.8 dB in SSSDNAH and 5.1 dB in S0NAH (head shadow), 3.4 dB in S0N0 (summation), and 4.6 dB in S0NSSD and 5.1 dB in SAHNSSD (squelch). CROS yielded a significant head shadow benefit of 2.4 dB in SSSDNAH and a significant deterioration in squelch of 2.5 dB in S0NSSD and SAHNSSD, but no summation effect. With BCD, there was a significant summation benefit of 1.5 dB, but no head shadow nor squelch effect. For SSN, significant improvements in SRT with CI compared to preoperatively unaided were found in three spatial configurations. Median benefits with CI at 6 months were: 8.5 dB in SSSDNAH and 4.6 dB in S0NAH (head shadow), 1.4 dB in S0N0 (summation), but no squelch. CROS showed a significant head shadow benefit of 1.7 dB in SSSDNAH, but no summation effect, and a significant deterioration in squelch of 2.9 dB in S0NSSD and 3.2 dB in SAHNSSD. With BCD, no binaural effect was obtained. Longitudinally, we found significant head shadow benefits with a CI in SSSDNAH in both maskers at all postoperative intervals and in S0NAH at 3 and 6 months post-activation.

CONCLUSION

With a CI, a clear benefit for masked speech perception was observed for all binaural effects. Benefits with CROS and BCD were more limited. CROS usage was detrimental to the squelch effect.

Impact of processing-latency induced interaural delay and level discrepancy on sensitivity to interaural level differences in cochlear implant users

PURPOSE

This study investigated whether an interaural delay, e.g. caused by the processing latency of a hearing device, can affect sensitivity to interaural level differences (ILDs) in normal hearing subjects or cochlear implant (CI) users with contralateral normal hearing (SSD-CI).

METHODS

Sensitivity to ILD was measured in 10 SSD-CI subjects and in 24 normal hearing subjects. The stimulus was a noise burst presented via headphones and via a direct cable connection (CI). ILD sensitivity was measured for different interaural delays in the range induced by hearing devices. ILD sensitivity was correlated with results obtained in a sound localization task using seven loudspeakers in the frontal horizontal plane.

RESULTS

In the normal hearing subjects the sensitivity to interaural level differences deteriorated significantly with increasing interaural delays. In the CI group, no significant effect of interaural delays on ILD sensitivity was found. The NH subjects were significantly more sensitive to ILDs. The mean localization error in the CI group was 10.8° higher than in the normal hearing group. No correlation between sound localization ability and ILD sensitivity was found.

CONCLUSION

Interaural delays influence the perception of ILDs. For normal hearing subjects a significant decrement in sensitivity to ILD was measured. The effect could not be confirmed in the tested SSD-CI group, probably due to a small subject group with large variations. The temporal matching of the two sides may be beneficial for ILD processing and thus sound localization for CI patients. However, further studies are needed for verification.

Cochlear Implants for Single-Sided Deafness: Quality of Life, Daily Usage, and Duration of Deafness

OBJECTIVE

To report our experience for adults undergoing cochlear implantation (CI) for single-sided deafness (SSD).

METHODS

This is a retrospective case series for adults with SSD who underwent CI between January 2013 and May 2021 at our institution. CNC and AzBio speech recognition scores, Tinnitus Handicap Inventory (THI), Speech, Spatial, and Qualities of Hearing Scale (SSQ12), datalogging, and the Cochlear Implant Quality of Life (CIQOL)-10 Global measure were utilized.

RESULTS

Sixty-six adults underwent CI for SSD (median 51.3 years, range 20.0-74.3 years), and 57 (86.4%) remained device users at last follow-up. Compared to pre-operative performance, device users demonstrated significant improvement in speech recognition scores and achieved peak performance at six months post-activation for CNC (8.0% increased to 45.6%, p < 0.0001) and AzBio in quiet (12.2% increased to 59.5%, p < 0.0001). THI was decreased at 6 months post-implantation (58.1-14.6, p < 0.0001), with 77% of patients reporting improved or resolved tinnitus. Patients demonstrated improved SSQ12 scores as well as the disease-specific CIQOL-10 Global questionnaire. Duration of deafness was not associated with significant differences in speech recognition performance. Average daily wear time was positively associated with CNC and AzBio scores as well as post-operative CIQOL-10 scores.

CONCLUSIONS

Herein we present the largest cohort of adult CI recipients with SSD with data on speech recognition scores, tinnitus measures, and SSQ12. Novel insights regarding the correlation of datalogging, duration of deafness, and CI-specific quality of life (CIQOL-10) metrics are discussed. Data continue to support CI as an efficacious treatment option for SSD.

LEVEL OF EVIDENCE

4 Laryngoscope, 133:2362-2370, 2023.

Cochlear Implantation Outcomes in Adults With Single-Sided Deafness: A Systematic Review and Meta-analysis

OBJECTIVE

To assess spatial hearing, tinnitus, and quality-of-life outcomes in adults with single-sided deafness (SSD) who underwent cochlear implantation.

DATABASES REVIEWED

PubMed, MEDLINE, Embase, Cochrane Central Register of Controlled Trials, Web of Science, and Scopus databases were searched from January 2008 to September 2021 following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines.

METHODS

Studies reporting spatial hearing, tinnitus, and quality-of-life outcomes in adult cochlear implant (CI) recipients (≥18 yr old) with SSD were evaluated. Study characteristics, demographic data, spatial hearing (speech recognition in noise, sound source localization), tinnitus (severity, loudness), and quality-of-life outcomes were collected.

RESULTS

From an initial search of 1,147 articles, 36 studies that evaluated CI use in 796 unique adults with SSD (51.3 ± 12.4 yr of age at time of implantation) were included. The mean duration of deafness was 6.2 ± 9.6 years. There was evidence of improvement for speech recognition in noise using different target-to-masker spatial configurations, with the largest benefit observed for target-to-masker configurations assessing head shadow (mean, 1.87-6.2 dB signal-to-noise ratio). Sound source localization, quantified as root-mean-squared error, improved with CI use (mean difference [MD], -25.3 degrees; 95% confidence interval [95% CI], -35.9 to -14.6 degrees; p < 0.001). Also, CI users reported a significant reduction in tinnitus severity as measured with the Tinnitus Handicap Inventory (MD, -29.97; 95% CI, -43.9 to -16.1; p < 0.001) and an improvement in spatial hearing abilities as measured with the Spatial, Speech, and Qualities of Hearing questionnaire (MD, 2.3; 95% CI, 1.7 to 2.8; p < 0.001).

CONCLUSIONS

Cochlear implantation and CI use consistently offer improvements in speech recognition in noise, sound source localization, tinnitus, and perceived quality of life in adults with SSD.

Hearing rehabilitation for unilateral deafness using a cochlear implant: the influence of the subjective duration of deafness on speech intelligibility

BACKGROUND

For patients with single sided deafness (SSD) or severe asymmetric sensorineural hearing loss (ASHL), cochlear implantation remains the only solution to restore bilateral hearing capacity. Prognostically, the duration of hearing loss in terms of audiological outcome is not yet clear. Therefore, the aim of this study was to retrospectively investigate the influence of subjective deafness duration on postoperative speech perception after cochlear implantation for SSD as well as its impact on quality of life.

MATERIALS AND METHODS

The present study included a total of 36 adults aged 50.2 ± 15.5 years who underwent CI for SSD/ASHL at our clinic between 2010 and 2015. Patients were audiometrically assessed at 3 and 12-36 months postoperatively. Test results were correlated with self-reported duration of deafness. Quality of life was assessed by questionnaire.

RESULTS

Mean duration of deafness was 193.9 ± 185.7 months. The side-separated hearing threshold showed an averaged target range between 30 and 40 dB HL. Freiburg monosyllable test increased from 0% pre-operatively to 20% after 3 months (p = 0.001) and to 50% after 12-36 months (p = 0.002). There was a significant correlation between audiometric outcome and subjective deafness duration at 12-36 months postoperatively (r = - 0.564; p = 0.02) with a cutoff for open-set monosyllable recognition at a duration of deafness of greater than 408 months. Quality of life was significantly improved by CI.

CONCLUSIONS

CI implantation in unilaterally deafened patients provides objective and subjective benefits. Duration of deafness is unlikely to be an independent negative predictive factor and thus should not generally be considered as contraindication.

Selective attention decoding in bimodal cochlear implant users

The growing group of cochlear implant (CI) users includes subjects with preserved acoustic hearing on the opposite side to the CI. The use of both listening sides results in improved speech perception in comparison to listening with one side alone. However, large variability in the measured benefit is observed. It is possible that this variability is associated with the integration of speech across electric and acoustic stimulation modalities. However, there is a lack of established methods to assess speech integration between electric and acoustic stimulation and consequently to adequately program the devices. Moreover, existing methods do not provide information about the underlying physiological mechanisms of this integration or are based on simple stimuli that are difficult to relate to speech integration. Electroencephalography (EEG) to continuous speech is promising as an objective measure of speech perception, however, its application in CIs is challenging because it is influenced by the electrical artifact introduced by these devices. For this reason, the main goal of this work is to investigate a possible electrophysiological measure of speech integration between electric and acoustic stimulation in bimodal CI users. For this purpose, a selective attention decoding paradigm has been designed and validated in bimodal CI users. The current study included behavioral and electrophysiological measures. The behavioral measure consisted of a speech understanding test, where subjects repeated words to a target speaker in the presence of a competing voice listening with the CI side (CIS) only, with the acoustic side (AS) only or with both listening sides (CIS+AS). Electrophysiological measures included cortical auditory evoked potentials (CAEPs) and selective attention decoding through EEG. CAEPs were recorded to broadband stimuli to confirm the feasibility to record cortical responses with CIS only, AS only, and CIS+AS listening modes. In the selective attention decoding paradigm a co-located target and a competing speech stream were presented to the subjects using the three listening modes (CIS only, AS only, and CIS+AS). The main hypothesis of the current study is that selective attention can be decoded in CI users despite the presence of CI electrical artifact. If selective attention decoding improves combining electric and acoustic stimulation with respect to electric stimulation alone, the hypothesis can be confirmed. No significant difference in behavioral speech understanding performance when listening with CIS+AS and AS only was found, mainly due to the ceiling effect observed with these two listening modes. The main finding of the current study is the possibility to decode selective attention in CI users even if continuous artifact is present. Moreover, an amplitude reduction of the forward transfer response function (TRF) of selective attention decoding was observed when listening with CIS+AS compared to AS only. Further studies to validate selective attention decoding as an electrophysiological measure of electric acoustic speech integration are required.

Task force Guideline of Brazilian Society of Otology - hearing loss in children - Part II - Treatment

OBJECTIVES

To provide an overview of the main evidence-based recommendations for the diagnosis of hearing loss in children and adolescents aged 0-18 years.

METHODS

Task force members were educated on knowledge synthesis methods, including electronic database search, review and selection of relevant citations, and critical appraisal of selected studies. Articles written in English or Portuguese on childhood hearing loss were eligible for inclusion. The American College of Physicians' guideline grading system and the American Thyroid Association's guideline criteria were used for critical appraisal of evidence and recommendations for therapeutic interventions.

RESULTS

The topics were divided into 2 parts: (1) treatment of sensorineural hearing loss: individual hearing aids, bilateral cochlear implants, cochlear implants in young children, unilateral hearing loss, and auditory neuropathy spectrum disorder; and (2) treatment of conductive/mixed hearing loss: external/middle ear malformations, ventilation tube insertion, and tympanoplasty in children.

CONCLUSIONS

In children with hearing loss, in addition to speech therapy, Hearing AIDS (HAs) or implantable systems may be indicated. Even in children with profound hearing loss, both the use of HAs and behavioral assessments while using the device are important.

(Even Off-Label) Cochlear Implantation in Single-Sided Deafness and Asymmetric Hearing Loss Results in Measurable Objective and Subjective Benefit

OBJECTIVE

To quantify objective and subjective outcomes in cochlear implant (CI) recipients with asymmetric hearing loss, including single-sided deafness (SSD) whose candidacy was determined on an ear-specific basis when word recognition was 50% or less.

STUDY DESIGN

Retrospective case review.

SETTING

Tertiary referral center.

BACKGROUND

The effectiveness of CI in cases of SSD and asymmetric hearing loss (AHL) has been described in terms of tinnitus suppression, improved speech recognition in quiet and noise, enhanced localization ability, and improved quality of life. However, CI is not yet routinely offered as a top option or standard of care for these individuals. Recent Food and Drug Administration (FDA) labeling limits aided word recognition in the ear to be implanted to only 5% in cases of AHL/SSD, which is significantly poorer than 40 to 50%, which is often referenced in cases of bilateral hearing loss. Anecdotal experience suggests that patients with much better preoperative word recognition than 5% can benefit from CI.

METHODS

We conducted a retrospective chart review of all adult CI candidates, with one ear exhibiting consonant-nucleus-consonant (CNC) word recognition scores at least 50% and one ear not meeting CI candidacy (i.e., CNC word recognition >50%). Outcome variables of interest included word and sentence recognition and subjective handicap questionnaires (hearing, tinnitus, dizziness) and the Speech Spatial Qualities questionnaire.

RESULTS

Statistically and clinically significant improvement in speech understanding (word, sentence, sentence in noise) was noted for both the SSD and AHL groups in the implanted ear. There were statistically and clinically significant subjective improvements noted for both groups on the Hearing Handicap Inventory, the Tinnitus Handicap Inventory, and the Speech Spatial Qualities questionnaire by 1 month after activation. There were no significant differences between the AHL and SSD groups on either objective or subjective measures of the implanted ear. Individual word understanding improved for the majority of recipients across both groups and is not dependent on meeting the FDA criteria of less than 5%.

CONCLUSIONS

Cochlear implantation is a viable option with measurable objective and perceived benefits for recipients with preoperative aided CNC word scores exceeding current FDA labeling. There is no significant difference between the AHL and SSD groups, suggesting that candidacy and outcome expectations should be set based on the ear to be implanted alone, without regard for the ability of the better hearing ear.

American Cochlear Implant Alliance Task Force Guidelines for Clinical Assessment and Management of Adult Cochlear Implantation for Single-Sided Deafness

The indications for cochlear implantation have expanded to include individuals with profound sensorineural hearing loss in the impaired ear and normal hearing (NH) in the contralateral ear, known as single-sided deafness (SSD). There are additional considerations for the clinical assessment and management of adult cochlear implant candidates and recipients with SSD as compared to conventional cochlear implant candidates with bilateral moderate to profound sensorineural hearing loss. The present report reviews the current evidence relevant to the assessment and management of adults with SSD. A systematic review was also conducted on published studies that investigated outcomes of cochlear implant use on measures of speech recognition in quiet and noise, sound source localization, tinnitus perception, and quality of life for this patient population. Expert consensus and systematic review of the current literature were combined to provide guidance for the clinical assessment and management of adults with SSD.

A Modelling Study on the Comparison of Predicted Auditory Nerve Firing Rates for the Personalized Indication of Cochlear Implantation

The decision of whether to perform cochlear implantation is crucial because implantation cannot be reversed without harm. The aim of the study was to compare model-predicted time–place representations of auditory nerve (AN) firing rates for normal hearing and impaired hearing with a view towards personalized indication of cochlear implantation. AN firing rates of 1024 virtual subjects with a wide variety of different types and degrees of hearing impairment were predicted. A normal hearing reference was compared to four hearing prosthesis options, which were unaided hearing, sole acoustic amplification, sole electrical stimulation, and a combination of the latter two. The comparisons and the fitting of the prostheses were based on a ‘loss of action potentials’ (LAP) score. Single-parameter threshold analysis suggested that cochlear implantation is indicated when more than approximately two-thirds of the inner hair cells (IHCs) are damaged. Second, cochlear implantation is also indicated when more than an average of approximately 12 synapses per IHC are damaged due to cochlear synaptopathy (CS). Cochlear gain loss (CGL) appeared to shift these thresholds only slightly. Finally, a support vector machine predicted the indication of a cochlear implantation from hearing loss parameters with a 10-fold cross-validated accuracy of 99.2%.

The Quality of Life in the Elderly with Acquired Single-Sided Deafness

This study was aimed at assessing the negative impact of an acquired single-sided deafness on quality of life of the elderly. Prospective analysis of outpatient records was carried out to identify elderly patients with single-sided deafness using pure tone audiometry. The main inclusion criteria were age over 60, a 90 dB or higher threshold of an affected ear, a 30 dB or less threshold of an intact ear, and an acquired single-sided hearing loss with sudden onset and a deafness duration of less than 5 years. Taking the inclusion criteria into account, two groups were formed: the main group with single-sided deaf patients (n = 25) and the control group of patients with normal hearing (n = 25). All participants were surveyed with the PSQ, HHIE, and THI questionnaires. Some changes in psychological status in the group of patients with single-sided deafness in comparison with the group of normal hearing participants were revealed. The scores of the questionnaires showed increased stress and anxiety levels and deterioration in their quality of life. Patients with single-sided deafness complained about severe tinnitus in an affected ear, worse intelligibility of speech in a noisy environment and a constant need to adapt to the different acoustic situations that in turn affected psychoemotional homeostasis badly, intensifying the severity of stress, and their quality of life.

Impact of Reverberation on Speech Perception and Sound Localization Accuracy in Cochlear Implant Users With Single-Sided Deafness

OBJECTIVES

The aim of this study was to compare the impact of reverberation on sound localization accuracy and speech perception in noise between subjects with single-sided deafness using a cochlear implant (SSD-CI) and a normal-hearing control group.

METHODS

Nine SSD-CI subjects and 21 normal-hearing subjects participated in the study. In Experiment 1, the sound localization accuracy was measured with and without reverberation. In Experiment 2, speech reception thresholds were determined with four asymmetrically arranged noise sources in free-field and in reverberation. For the realization of reverberation, a room simulation system comprising of 128 loudspeakers was used.

RESULTS

No significant impact of reverberation was found on the sound localization accuracy of the SSD-CI subjects (free-field: 12.6°, reverberation: 11.9°), whereas the normal-hearing subjects performed significantly worse in reverberation (free-field: 1.8°, reverberation: 3.3°).Both subject groups experienced significantly deteriorated speech reception thresholds due to reverberation (pSSD-CI = 0.008, pNH < 0.001). Mean speech reception thresholds in the SSD-CI subjects were -9.7 dB SNR (free-field) and -4.2 dB SNR (reverberation) and a median individual decrease of 5.7 dB SNR in reverberation. Mean speech reception thresholds in the normal-hearing group were -14.0 dB SNR (free-field) and -10.3 dB SNR (reverberation).

CONCLUSION

A strong deterioration of sound localization accuracy due to reverberation did not occur. However, although partial restoration of binaural hearing is assumed in SSD-CI users, the impact of reverberation on speech perception in noise is much stronger compared to normal-hearing.

Mythbusters! The Truth about Common Misconceptions in Cochlear Implantation

Cochlear implantation (CI) is the preferred method of hearing rehabilitation when patients cannot perform well with traditional amplification. Unfortunately, there are still significant misconceptions around this life-changing intervention. The goal of this article is to address some of the most common myths around CI surgery. After reading this article, the learner will be able to explain the utility of CI in patients with residual hearing and recognize that insurance coverage is widespread. The reader will be able to list common risks associated with this well-tolerated procedure including anesthetic risk and the risk of vestibular dysfunction. Additionally, the reader will be able to identify the significant positive impact of CI on patients' quality of life. Finally, the reader will identify that many patients can safely have an MRI scan after implantation, including nearly all contemporary recipients.

Assessment of Receptive and Expressive Language Skills Among Young Children With Prelingual Single-Sided Deafness Managed With Early Cochlear Implantation

IMPORTANCE

Pediatric single-sided deafness (SSD) can seriously affect development, causing impaired spatial hearing skills, speech-language delays, and academic underachievement. Early cochlear implantation likely improves hearing-related outcomes, but its association with language development remains unclear.

OBJECTIVE

To investigate whether early cochlear implantation is associated with language outcomes for children with prelingual SSD.

DESIGN, SETTING, AND PARTICIPANTS

The Cochlear Implant for Children and One Deaf Ear study was initiated in 2015 and recruited participants at 4 academic hospitals in Flanders, Belgium, through 2019. This cohort study included 3 groups of children aged 2 to 5 years: children with SSD and a cochlear implant, children with SSD without a cochlear implant, and a control group with normal hearing. Language and hearing skills were assessed 1 to 2 times per year until the age of 10 years. Study completion rates were high (82%). Data analysis was performed from October to December 2020.

EXPOSURE

Unilateral cochlear implant.

MAIN OUTCOMES AND MEASURES

Longitudinal vocabulary, grammar, and receptive language scores. The implanted group was hypothesized to outperform the nonimplanted group on all language tests.

RESULTS

During the recruitment period, 47 children with prelingual SSD without additional disabilities were identified at the participating hospitals. Fifteen of the 34 children with an intact auditory nerve received a cochlear implant (44%, convenience sample). Sixteen of the remaining children were enrolled in the SSD control group (50%). Data from 61 children (mean [SD] age at the time of enrollment, 2.08 [1.34] years; 26 girls [42%]) were included in the analysis: 15 children with SSD and a cochlear implant, 16 children with SSD without a cochlear implant, and 30 children with normal hearing. Children with SSD and a cochlear implant performed in line with their peers with normal hearing with regard to grammar. In contrast, children with SSD without a cochlear implant had worse grammar scores than the group with implants (-0.76; 95% CI, -0.31 to -1.21; P = .004) and the group with normal hearing (-0.53; 95% CI, -0.91 to -0.15; P = .02). The 3 groups had similar vocabulary and receptive language abilities.

CONCLUSIONS AND RELEVANCE

These findings suggest that early cochlear implantation is associated with normal grammar development in young children with prelingual SSD. Although further follow-up will reveal the long-term outcomes of the cochlear implant for other skills, the current results will help clinicians and policy makers identify the best treatment option for these children.

Development of cortical auditory responses to speech in noise in unilaterally deaf adults following cochlear implantation

BACKGROUND

For patients with single-sided deafness (SSD), restoration of binaural function via cochlear implant (CI) has been shown to improve speech understanding in noise. The objective of this study was to investigate changes in behavioral performance and cortical auditory responses following cochlear implantation.

DESIGN

Prospective longitudinal study.

SETTING

Tertiary referral center.

METHODS

Six adults with SSD were tested before and 12 months post-activation of the CI. Six normal hearing (NH) participants served as experimental controls. Speech understanding in noise was evaluated for various spatial conditions. Cortical auditory evoked potentials were recorded with /ba/ stimuli in quiet and in noise. Global field power and responses at Cz were analyzed.

RESULTS

Speech understanding in noise significantly improved with the CI when speech was presented to the CI ear and noise to the normal ear (p<0.05), but remained poorer than that of NH controls (p<0.05). N1 peak amplitude measure in noise significantly increased after CI activation (p<0.05), but remained lower than that of NH controls (p<0.05) at 12 months. After 12 months of CI experience, cortical responses in noise became more comparable between groups.

CONCLUSION

Binaural restoration in SSD patients via cochlear implantation improved speech performance noise and cortical responses. While behavioral performance and cortical auditory responses improved, SSD-CI outcomes remained poorer than that of NH controls in most cases, suggesting only partial restoration of binaural hearing.

New Medical Device and Therapeutic Approvals in Otolaryngology: State of the Art Review of 2019

OBJECTIVE

To review new devices and drugs relevant to otolaryngology-head and neck surgery that were approved by the US Food and Drug Administration (FDA) in 2019.

DATA SOURCES

Approval notifications for 2019 were extracted from the ENT (ear, nose, and throat) and general and plastic surgery sections of the FDA's medical devices and therapeutics listings.

REVIEW METHODS

New therapeutics and medical devices identified from the query were analyzed by members of the American Academy of Otolaryngology-Head and Neck Surgery's Medical Devices and Drugs Committee. Technologies were assessed by 2 independent reviewers to ascertain relevance to otolaryngology, prioritized, and classified to subspecialty field with critical review based on extant scientific literature.

CONCLUSIONS

Query of the FDA drug and device database returned 105 ENT devices (50 cleared, 55 with premarket approval, and 0 de novo), 543 general and plastic surgery devices (372 cleared, 170 with premarket approval, and 1 de novo), and 46 new otolaryngology-relevant drug approvals that occurred in 2019. Advances spanned all subspecialty areas with otology predominating, primarily due to hearing-related technologies. While scientific evidence was available for all new devices, there was significant heterogeneity in rigor of supporting scientific data.

IMPLICATIONS FOR PRACTICE

Technological and pharmaceutical innovation is an important catalyst for advances in the surgical specialties. Familiarity with new devices and therapeutics in otolaryngology-head and neck surgery ensures that clinicians keep abreast of developments with potential to improve prevailing standards of care.

Restoration of cortical symmetry and binaural function: Cortical auditory evoked responses in adult cochlear implant users with single sided deafness

Background

Cochlear implantation for single-sided deafness (SSD) is the only treatment option with the potential to restore binaural hearing cues. Significant binaural benefit has been measured in adults by speech in noise and localisation tests, who receive a cochlear implant for SSD, however, little is known on the cortical changes that help provide this benefit. In the present study, detection of sound in the auditory cortex, speech testing and localisation was used to investigate the ability of a cochlear implant (CI) to restore auditory cortical latencies and improve binaural benefit in the adult SSD population.

Methods

Twenty-nine adults with acquired single-sided deafness who received a CI in adulthood were studied. Speech perception in noise was tested using the Bamford-Kowal-Bench speech-in-noise test, localisation ability was measured using the auditory speech sounds evaluation (AδE) localisation test and cortical auditory evoked responses, comparing N1-P2 latencies recorded from the normal hearing ear and cochlear implant were used to investigate the synchrony of the cortical pathway from the CI and normal hearing ear (NHe) with binaural hearing function.

Results

There was a significant improvement in speech perception in noise in all spatial configurations S0/N0 (Z = -3.066, p<0.002), S0/NHE (Z = -4.031, p<0.001), SCI/NHE (Z = -3.851, p<0.001). Localization significantly improved when tested with the cochlear implant on (p<0.001) with a shorter duration of deafness correlating to a greater improvement in localisation ability F(1:18) = 6.854; p = 0.017). There was no significant difference in N1-P2 latency recorded from the normal hearing ear and the CI.

Conclusion

Cortical auditory evoked response latencies recorded from the CI and NHe showed no significant difference, indicating that the detection of sound in the auditory cortex occurred simultaneously, providing the cortex with auditory information for binaural hearing.

Outcomes of unilateral idiopathic sudden sensorineural hearing loss: Two decades of experience

OBJECTIVES

(a) Determine the demographic and medical risk factors for patients who presented with unilateral idiopathic sudden sensorineural hearing loss (ISSNHL); (b) identify treatments that patients underwent; (c) evaluate the adequacy of follow-up and compliance with long-term hearing rehabilitation.

METHODS

Retrospective review of patients who presented with unilateral ISSNHL between January 1998 and December 2017 at a tertiary care academic medical center.

RESULTS

Two hundred-four patients met inclusion criteria. Of these, 129 (63.2%) did not undergo treatment at an outside hospital prior to our evaluation. In this subgroup, the average pretreatment pure tone average (PTA) was 61.9 ± 2.5 dB (dB). The most common treatment was oral steroids and was recommended in 76 patients (59.9%). Patients also underwent intratympanic (IT) steroid injections (7.2%) or oral steroids followed by salvage IT injections (19.4%). Mean follow-up duration was 17.9 (±29.2) months, and posttreatment PTA (45.6 ± 2.6 dB) was significantly better than baseline (P < .001). In this cohort, hearing amplification was infrequently recommended. Less than 20% of patients reported active hearing amplification use at their most recent visit. At follow-up, 90 patients (69.8%) reported subjective improvement in hearing after treatment. Only 55 patients (42.6%) showed improvement in PTA compared to their pretreatment audiograms.

CONCLUSION

Many patients with ISSNHL experienced audiometric improvement after treatments, but most had persistent hearing loss. The duration of follow-up was short. Most patients did not use long-term hearing amplification. Future studies are needed to identify factors that contribute to reduced follow-up and low compliance with hearing amplification use in ISSNHL.

LEVEL OF EVIDENCE

2c.

Cortical auditory responses according to hearing rehabilitation in unilateral hearing loss

OBJECTIVE

To assess the impact of rehabilitation systems (CROS: Contralateral Routing of Signal; BAHA: Bone-Anchored Hearing Aid; CI: cochlear implant) on cortical auditory evoked potentials (CAEP) and auditory performance in unilateral hearing loss.

SUBJECTS AND METHOD

Twenty-one adults with unilateral hearing loss, using CROS (n=6), BAHA (n=6) or CI (n=9), were included. Seven normal-hearing subjects served as controls. CAEPs were recorded for a (/ba/) speech stimulus; for patients, tests were conducted with and without their auditory rehabilitation. Amplitude and latency of the various CAEP components of the global field power (GFP) were measured, and scalp potential fields were mapped. Behavioral assessment used sentence recognition in noise, with and without spatial cues.

RESULTS

Only CI induced N1 peak amplitude change (P<0.05). CI and CROS increased polarity inversion amplitude in the contralateral ear, and frontocentral negativity on the scalp potential map. CI improved understanding when speech was presented to the implanted ear and noise to the healthy ear, and vice-versa.

CONCLUSION

Cochlear implantation had the greatest impact on CAEP morphology and auditory performance. A longitudinal study could analyze progression of cortical reorganization.