Evidence-Based Recommendation for Bilateral Cochlear Implantation in Adults.

The Optimized Pitch and Language (OPAL) strategy enhances pitch perception through coding of fundamental frequency (F0) amplitude modulation information in the stimulus envelope delivered to a cochlear implant. Previous research using a prototype of the strategy demonstrated significant benefits in musical pitch and lexical tone discrimination tasks with no degradation in speech recognition when compared with the clinical Advanced Combination Encoder (ACE) strategy in a small group of subjects. Based on those studies, a modified version of the strategy was implemented in the commercial Nucleus CP900 series processor. The aims of the present study were to establish whether the CP900 OPAL implementation continued to provide improved F0 pitch perception in a speech intonation task with no degradation to speech perception in quiet and noise, when compared with the clinical ACE strategy in a larger cohort of subjects. Further aims were to evaluate fitting procedures and subject acclimatization to the strategy after take-home experience. Twenty experienced adult cochlear implant recipients were enrolled in the study. Two subjects withdrew during the study leaving 18 sets of data for analysis. A repeated-measures single-subject design with take-home experience was used to test for improved speech intonation perception using OPAL compared with ACE and for comparable performance between strategies for open-set word recognition in quiet at two presentation levels, sentence recognition in adaptive 4-talker babble noise, and speech intelligibility ratings. The stimulation rate employed for OPAL was 1200 pulses per second/channel which was higher than the default clinical rate of 900 pulses per second/channel used for ACE by all subjects in the present study. Two variations of the OPAL "F0 restore gain" (the gain applied to restore the loudness of modulated channels) were investigated: "custom" measured per subject and "default" which was the average of all subject custom gains. A significant group mean benefit on the intonation test of 8.5% points was shown for OPAL compared with ACE. There was a significant period of adaptation to OPAL with significantly poorer sentence in noise scores acutely and after only 2 weeks of take-home experience. After 4 weeks of take-home experience, comparable word perception in quiet and sentence perception in noise for OPAL were obtained. Furthermore, there was good subject acceptability in the field with comparable speech intelligibility ratings between strategies. Results of the fitting procedure showed that OPAL did not require any additional steps compared with fitting of ACE. A default F0 restore gain provided comparable outcomes to a custom gain setting. The CP900 OPAL implementation provided a significant benefit to perception of speech intonation when compared with ACE. Comparable speech perception (in quiet and noise) and subjective ratings of speech intelligibility between strategies were also achieved after a period of acclimatization. These outcomes are consistent with results of earlier studies using prototype versions of the strategy and reaffirm its potential for improvement of F0 pitch perception in speech while preserving coding of segmental speech information. Furthermore, the OPAL strategy can be programmed into subject's processors using the same fitting procedures used for ACE thereby simplifying its adoption in clinical settings.

Assessment of the clinical effectiveness of bilateral cochlear implantation compared with unilateral cochlear implantation or bimodal stimulation, in adults with severe-to-profound hearing loss. In 2007, the National Institute for Health and Clinical Excellence (NICE) in the U.K. conducted a systematic review on cochlear implantation. This study forms an update of the adult part of the NICE review. The electronic databases MEDLINE and Embase were searched for English language studies published between October 2006 and March 2011. Studies were included that compared bilateral cochlear implantation with unilateral cochlear implantation and/or with bimodal stimulation, in adults with severe-to-profound sensorineural hearing loss. Speech perception in quiet and in noise, sound localization and lateralization, speech production, health-related quality of life, and functional outcomes were analyzed. Data extraction forms were used to describe study characteristics and the level of evidence. The effect size was calculated to compare different outcome measures. Pooling of data was not possible because of the heterogeneity of the studies. As in the NICE review, the level of evidence of the included studies was low, although some of the additional studies showed less risk of bias. All studies showed a significant bilateral benefit in localization over unilateral cochlear implantation. Bilateral cochlear implants were beneficial for speech perception in noise under certain conditions and several self-reported measures. Most speech perception in quiet outcomes did not show a bilateral benefit. The current review provides additional evidence in favor of bilateral cochlear implantation, even in complex listening situations.

Introduction: Benefits of bilateral cochlear implants (CI) may be compromised by delays to implantation of either ear. This study aimed to evaluate the effects of sequential bilateral CI use in children who received their first CI at young ages, using a clinical set-up. Methods: One-channel cortical auditory evoked potentials and speech perception in quiet and noise were evoked at repeated times (0, 3, 6, 12 months of bilateral CI use) by unilateral and bilateral stimulation in 28 children with early-onset deafness. These children were unilaterally implanted before 3.69 years of age (mean ± SD of 1.98 ± 0.73 years) and received a second CI after 5.13 ± 2.37 years of unilateral CI use. Comparisons between unilaterally evoked responses were used to measure asymmetric function between the ears and comparisons between bilateral responses and each unilateral response were used to measure the bilateral benefit. Results: Chronic bilateral CI promoted changes in cortical auditory responses and speech perception performance; however, large asymmetries were present between the two unilateral responses despite ongoing bilateral CI use. Persistent cortical differences between the two sides at 1 year of bilateral stimulation were predicted by increasing age at the first surgery and inter-implant delay. Larger asymmetries in speech perception occurred with longer inter-implant delays. Bilateral responses were more similar to the unilateral responses from the first rather than the second CI. Conclusion: These findings are consistent with the development of the aural preference syndrome and reinforce the importance of providing bilateral CIs simultaneously or sequentially with very short delays.

Objectives To perform a systematic literature review (SLR) on hearing and quality-of-life (QoL) benefits of bilateral versus unilateral cochlear implants (CIs) in adults with sensorineural hearing loss (SNHL), and to quantify benefits through a meta-analysis when feasible. Methods Embase, MEDLINE, and Cochrane were searched from January 2005–June 2022. Eligible studies presented effectiveness of CIs and/or QoL of adult CI users. Articles that presented numerical point estimates for, or numerical difference between, bilateral and unilateral CI, and measures of uncertainty were considered for meta-analysis, with data analyzed using fixed- and random-effects models. Results Thirty-five articles were included. There was a trend of significant improvement with bilateral CIs in sound localization and binaural redundancy. A meta-analysis confirmed statistically significant benefits in speech perception (in quiet, 12.6 percentage point [95% confidence interval: 7.1, 18.1] improvement; in noise, improvement in speech reception threshold of 1.5 dB signal-to-noise ratio [–1.5 dB; 95% confidence interval: −2.5, −0.4]). There were beneficial trends of bilateral CIs regarding head-shadow effect and binaural release from masking. Significant improvements in hearing-specific QoL were observed; generic QoL was mostly unchanged. Discussion Bilateral CIs provide audiological benefit over unilateral CI, resulting in hearing-specific QoL improvements. Lack of changes in generic QoL may reflect that instrument domains are insensitive to hearing-related changes when going from unilateral to bilateral CIs. Meta-analyses could not be performed for all hearing and QoL outcomes owing to variability in methodologies across studies. Conclusions These findings should be used to inform clinical decision-making to ensure the best outcomes for adults with bilateral SNHL.

The main objective of this study was to examine the effect of a classifier-based noise management algorithm (AutoSense Sky OS 3.0) on speech perception in noise in pediatric cochlear implant (CI) recipients and to compare the speech perception outcomes with typically hearing peers. This prospective observational study included nine children (ages 9-15 years) with bilateral CIs and nine age-matched, typically hearing peers. Speech perception outcomes were measured in noise using Pediatric AzBio sentences to compare performance in the omnidirectional microphone mode with the classifier-based automatic noise management mode at four signal-to-noise ratios. Ratings of listening ease and speech clarity were recorded to obtain subjective measures of benefit. Results from the bilateral CI recipients were compared to a group of typically hearing children. Paired t tests were used to evaluate outcomes. Classifier-based noise management improved speech perception in noise compared to listening in the omnidirectional microphone mode. CI group averages revealed a 21.4 percentage point and 47.1 percentage point improvement in speech perception when using the Sky OS 3.0 algorithm at 0 and -5 dB SNR, respectively. Listening ease and speech clarity were improved when using the classifier-based noise management algorithm. Pediatric CI recipients can benefit from classifier-based noise management. Given the difficult listening environments children face, especially in typical classroom settings while listening for learning, audiologists should consider activating classifier-based noise management in this population.

ObjectiveTo evaluate objective and subjective hearing outcomes in experienced cochlear implant users with single sided deafness (SSD CI) who used fitting maps created via anatomy-based fitting (ABF) and clinically-based fitting (CBF).ParticipantsTwelve SSD CI users with postlingual hearing loss.InterventionOTOPLAN (Version 3. (MED-EL) was used to determine intracochlear electrode contact positions using post-operative high-resolution flat panel volume computed tomography. From these positions, the corresponding center frequencies and bandwidths were derived for each channel. These were implemented in the clinical fitting software MAESTRO to yield an ABF map individualized to each user.Main Outcome MeasuresABF and CBF maps were compared. Objective speech perception in quiet and in noise, binaural effects, and self-perceived sound quality were evaluated.ResultsSignificantly higher speech perception in noise scores were observed with the ABF map compared to the CBF map (mean SRT50: -6.49 vs. -4.8 dB SNR for the S0NCI configuration and − 3.85 vs. -2.75 dB SNR for the S0N0 configuration). Summation and squelch effects were significantly increased with the ABF map (0.86 vs. 0.21 dB SNR for summation and 0.85 vs. -0.09 dB SNR for squelch). No improvement in speech perception in quiet or spatial release from masking were observed with the ABF map. A similar level of self-perceived sound quality was reported for each map. Upon the end of the study, all users opted to keep the ABF map. This preference was independent of the angular insertion depth of the electrode array.ConclusionsExperienced SSD CI users preferred using the ABF map, which gave them significant improvements in binaural hearing and some aspects of speech perception.

Objectives/HypothesesChildren with unilateral sensory hearing loss (UHL) struggle to understand speech in noise and locate the origin of sound and have reduced quality of hearing. This clinical trial will determine the benefits of cochlear implantation in children with UHL.Study DesignProspective clinical trial.MethodsTwenty children with at least moderate to profound sensory hearing loss and poor speech perception (word score <30%) in one ear and normal hearing in the contralateral ear participated in a Food and Drug Administration‐approved clinical trial. Subjects were evaluated for speech perception in quiet, speech perception in noise, sound localization, and subjective benefits after implantation.ResultsCNC word score perception in quiet significantly improved (1% to 50%, P < .0001) by 12 months after activation. Speech perception in noise by BKB‐SIN significantly improved in all three noise configurations; there was a 3.6 dB advantage in head shadow (P < .0001), a 1.6 dB advantage in summation (P = .003), and a 2.5 dB advantage in squelch (P = .0001). Localization improved by 26° at 9 months (P < .0001). Speech, Spatial, and Qualities (SSQ) demonstrated significant improvements in speech (5.2 to 7.4, P = .0012), qualities of hearing (5.9 to 7.5, P = .0056), and spatial hearing (2.7 to 6.6, P < .0001). SSQ subscales associated with binaural hearing were significantly improved, as was listening effort (P = .0082). Subjects demonstrated a non‐significant improvement in fatigue.ConclusionsThis study demonstrates that children with UHL significantly benefit from cochlear implantation.Level of EvidenceLevel 3 Laryngoscope, 132:S1–S18, 2022

There is a lack of high level of evidence studies comparing the effect of different treatment options for single-sided deafness (SSD). To determine the effect of a cochlear implant (CI), bone conduction device (BCD), contralateral routing of signals hearing aid (CROS), and no treatment on speech perception in noise outcomes in patients with SSD. In this single-center randomized clinical trial, adult patients with SSD were randomized into 3 groups: CI; a trial period with first a BCD on a headband and then a CROS; or a trial period with first a CROS and then a BCD on a headband. After the trial periods, patients opted for a BCD, CROS, or no treatment. Measurements were completed at baseline and at 3, 6, 12, and 24 months of follow-up. Data were collected from July 2014 to October 2021, and data were analyzed from December 2022 to May 2023. CI, BCD then CROS, or CROS then BCD. The primary outcome was the speech reception threshold in noise (SRTn), measured with speech and noise from the front (S0N0), speech directed to the poor ear and noise to the better ear (SpeNbe), and vice versa (SbeNpe). The secondary outcome was disease-specific quality of life (QOL). Of 120 included patients, 60 (50.0%) were female, and the mean (SD) age at inclusion was 53.0 (12.1) years. At the start of follow-up, 28 patients received a CI, 25 a BCD, 34 a CROS, and 26 chose no treatment. At 24 months, the CI group had significantly better speech perception in noise scores than the BCD group (difference in SRTn: SbeNpe, -4.7 dB; 95% confidence interval, -6.6 to -3.0; SpeNbe, -2.2 dB; 95% confidence interval, -4.6 to -1.1), the CROS group (difference in SRTn: S0N0, -1.3 dB; 95% confidence interval, -1.7 to -0.2; SbeNpe, -5.3 dB; 95% confidence interval, -6.0 to -3.1), and the no treatment group (difference in SRTn: SpeNbe, -6.3 dB; 95% confidence interval, -7.5 to -4.9). Compared with the no treatment group, the BCD and CROS groups showed significantly better (difference in SRTn for SpeNbe, -4.1 dB [95% confidence interval, -5.2 to -1.5] and -4.1 dB [95% confidence interval, -6.1 to -3.3], respectively) or worse (difference for SbeNpe, 4.0 dB [95% confidence interval, 2.6 to 6.2] and 4.6 dB [95% confidence interval, 2.8 to 5.7], respectively) speech perception in noise. Self-reported speech perception abilities were significantly better for the CI group compared with the BCD, CROS, and no treatment groups. In this randomized clinical trial, the CI group outperformed the BCD, CROS, and no treatment groups in terms of speech perception in noise and disease-specific QOL in patients with SSD after 24 months of follow-up. These results indicate that patients with SSD can partially regain the advantages of binaural hearing after treatment. trialregister.nl Identifier: NL4457.

Speech perception in noise is an important aspect of the rehabilitation of children with hearing loss. We aimed to evaluate the feasibility and reliability of the Dutch digits-in-noise (DIN) test in the clinical follow-up of children with hearing aids (HAs) and/or cochlear implants (CIs). A second aim of the study was to gain insight in the speech perception in noise performance of children with different degrees of hearing loss. We retrospectively analyzed DIN test data of Dutch-speaking children with hearing loss (N = 188; 5 to 18 years old). A free-field version of the DIN-test was used. Children with open-set phoneme recognition in quiet of >70% at 65 dB SPL (best aided condition) were included. Ages ranged from 5 to 18 years old. All were experienced HA or CI users and had used their device(s) for at least 1 year before the measurement in the study. The DIN-test was performed in the framework of a clinical rehabilitation program. During testing, children wore their own devices with normal daily programs. The average speech reception threshold (SRT) was -3.6 dB (SD 3.6) for the first list and significantly improved to -4.0 dB (SD 3.1) for the second list. HA users had a 4-dB better SRT compared with CI users. The larger the child's hearing loss, the worse the SRT is. However, 15% of the children who completed a first list of 24 trials were unable to complete a second list. Mean adaptive staircase trajectories across trials suggested that learning occurred throughout the first list, and that loss of sustained attention contributed to response variability during the second list. The DIN test can be used to assess speech perception in noise abilities for children with different degrees of hearing loss and using HAs or CIs. The children with hearing loss required a higher signal-to-noise ratio (SNR) than did normal-hearing children and the required SNR is larger as the hearing loss increases. However, the current measurement procedure should be optimized for use in standard pediatric audiological care, as 15% of the children were unable to conduct a second list after the first list to reach a more stable SNR.

The effect of bilateral application of bone-anchored hearing aids (BAHAs) was examined in terms of directional hearing and speech recognition in quiet and in noise in four patients with bilateral congenital atresia who, out of pure necessity, had been using a unilateral bone-conduction hearing aid since early life. This study comprised a prospective clinical evaluation in a single subject design; four patients with bilateral congenital atresia originating from the Nijmegen BAHA series participated. Three patients had Treacher Collins syndrome. All four patients had conductive, most probably, symmetrical, hearing loss. Recently these patients had applied for a second BAHA and were subsequently fitted bilaterally. With two BAHAs, all four patients showed significant improvement in sound localization. Also, speech perception in quiet showed significant improvement with bilateral application, and a significant improvement was found in speech perception in noise in three patients. These results suggest that patients with congenital conductive, symmetrical hearing loss will benefit from bilateral BAHAs.

Intervention for a Child with Auditory Neuropathy/Dys-synchrony

In this explorative study, the authors investigated the relationship between auditory and cognitive abilities and self-reported hearing disability. Thirty-two adults with mild to moderate hearing loss completed the Amsterdam Inventory for Auditory Disability and Handicap (AIADH; Kramer, Kapteyn, Festen, & Tobi, 1996) and performed the Text Reception Threshold (TRT; Zekveld, George, Kramer, Goverts, & Houtgast, 2007) test as well as tests of spatial working memory (SWM) and visual sustained attention. Regression analyses examined the predictive value of age, hearing thresholds (pure-tone averages [PTAs]), speech perception in noise (speech reception thresholds in noise [SRTNs]), and the cognitive tests for the 5 AIADH factors. Besides the variance explained by age, PTA, and SRTN, cognitive abilities were related to each hearing factor. The reported difficulties with sound detection and speech perception in quiet were less severe for participants with higher age, lower PTAs, and better TRTs. Fewer sound localization and speech perception in noise problems were reported by participants with better SRTNs and smaller SWM. Fewer sound discrimination difficulties were reported by subjects with better SRTNs and TRTs and smaller SWM. The results suggest a general role of the ability to read partly masked text in subjective hearing. Large working memory was associated with more reported hearing difficulties. This study shows that besides auditory variables and age, cognitive abilities are related to self-reported hearing disability.

Aims: To investigate the long-term effects of the fine structure processing (FSP) coding strategy on speech perception in noise and quality of life in experienced cochlear implant (CI) users. Methods: In a prospective comparative clinical trial, 32 experienced postlingually deafened CI recipients were upgraded from the Tempo+ to the Opus 2 audio processor, implementing FSP in one group and high-definition continuous interleaved sampling (HDCIS) coding strategy in another group with identical frequency ranges. Speech perception in noise testing and the Speech, Spatial and Qualities (SSQ) questionnaire were administered at 0, 6, 12 and 24 months after the upgrade. Results: FSP yielded significant long-term improvement of speech perception in noise of in total 13.2 dB from 16.2 dB SNR at the upgrade to 3.0 dB SNR after 24 months of FSP experience. No significant improvement of speech perception in noise over time was measured for the HDCIS group. With the SSQ questionnaire, a significant benefit of the FSP coding strategy was observed. Conclusions: The FSP coding strategy as implemented in the Med-EL Opus 2 audio processor improves speech perception in noise. This beneficial effect of FSP on speech perception in noise is not immediate but is significant after 12 months and further improves up to 24 months after implementation of FSP.

A significant relationship between hearing loss and cognitive impairment has been previously reported. Overall, improvement in speech perception in quiet and quality of life has been observed after cochlear implantation. However, the impact of hearing loss treatment using cochlear implantation on cognitive functions is yet to be fully elucidated. To investigate the impact of cochlear implantation on cognitive and psychological functions of older adults. Prospective patient-control study. A total of 39 participants took part in the study: 23 cochlear implant (CI) candidates (M = 69.04 ± 12.35 yr) and 16 CI recipients (M = 61.75 ± 15.62 yr). All participants completed an assessment of hearing (pure-tone thresholds and speech perception in quiet), and a computerised, nonverbal test battery of cognitive function assessment, as well as a depression, anxiety, and stress scale. Independent-sample t test scores for the changes between 0 and 12 months revealed that CI recipients performed significantly better on measures of simple reaction time, cognitive flexibility, paired-associate learning, working memory, and strategy use (p < 0.05) compared with implant candidates. Compared with the candidates, recipients also showed significantly lower stress scores (p < 0.05) after 1 year use of a CI. Our results indicate that even in participants with a long duration, severe to profound hearing loss, cochlear implantation has some impact on improving a number of cognitive functions. This finding warrants future longitudinal investigations with a large sample size to examine if the observed cognitive enhancement benefits are sustainable.

The Use of Listening Devices to Ameliorate Auditory Deficit in Children with Autism