Long-term outcomes on spatial hearing, speech recognition and receptive vocabulary after sequential bilateral cochlear implantation in children

Language, cognitive, and speech in noise perception abilities of children with cochlear ımplants: a comparative analysis by implantation period and bilateral versus unilateral cochlear implants

PURPOSE

The purpose of this study was to compare the language, cognitive, and speech in noise (SiN) perception abilities of children with cochlear implants (CIs) to those of their peers with NH by grouping them according to their implantation period (12-18 months/19-24 months) and unilateral/bilateral CI use.

METHODS

The sample comprised 50 children with cochlear implants (CIs) and 20 children with normal hearing (NH), ages 6-9 years. Children's language, cognitive, and speech in noise (SiN) perception skills were assessed.

RESULTS

Children with CIs between 12 and 18 months and 19 and 24 months performed more poorly than children with NH on language, verbal memory (VM), verbal-short-term memory (V-STM), verbal working memory (V-WM), rapid naming, and speech in noise (SiN) perception abilities measures (p < 0.001). In addition, children with CIs between 19 and 24 months performed worse on rapid naming and V-WM tasks than children with CIs between 12 and 18 months (p < 0.017). Children with unilateral and bilateral CI performed more poorly than children with NH on language, VM, V-STM, V-WM, rapid naming, and SiN perception abilities assessments (p < 0.001). Additionally children with unilateral CI users performed poorly than children with bilateral CI users on SiN perception (p < 0.017).

CONCLUSIONS

In children with congenital hearing loss (CHL), cochlear implantation between 12 and 18 months or sequential bilateral implantation is not sufficient for these children to perform like their NH peers in language, cognitive, and SiN perception abilities. In addition, intervention approaches should focus not only on increasing language skills, but also on cognitive abilities.

School adjustment of adolescents with sequential bilateral cochlear implants in mainstream school

OBJECTIVES

Little is known about the school adjustment of adolescents with sequential bilateral cochlear implants (CIs) in mainstream educational settings. This study aims to investigate the school adjustment of adolescents with sequential bilateral CIs, in comparison to those of age-matched adolescents with typical hearing (TH), to explore the relationships between individual variables and school adjustment in the bilateral CI group, and to assess the factors leading to strong school adjustment in the bilateral CI group.

METHODS

Twenty-five adolescents with sequential bilateral CIs and 30 adolescents with TH, aged 13-19 years, participated in this study. The adolescents completed the school adjustment scale (SAS).

RESULTS

The two groups were not significantly different on overall SAS scores. However, the TH group scored higher on the SAS than the sequential bilateral CI group with regard to communication skills and relationships with peers. In the bilateral CI group, SAS scores significantly correlated with open-set sentence and receptive vocabulary scores. Receptive vocabulary scores were a significant predictive factor for the level of school adjustment for the bilateral CI group.

CONCLUSION

Adolescents who received sequential bilateral CIs adapted well to mainstream schools. However, they did experience barriers to communication and to make friends in mainstream schools, and their level of school adjustment was affected by their receptive vocabulary skills.

Comparison of Outcomes in Unilateral and Bilateral Pediatric Cochlear Implants: Our Experience

The aim of our study is to compare the outcomes in unilateral and bilateral cochlear implants in pediatric age and also between simultaneous and sequential cochlear implant surgery. This retrospective study was carried out with 83 children aged between 12 months to 2.5 years which included 41 children with bilateral Cochlear implants and 42 with unilateral implants. Out of these 41 children, 21 were simultaneous and 20 were sequential cochlear implant. All the children were operated at civil hospital Gandhinagar, Gujarat, India. CAP, SIR, localization, traffic noise and speech in noise scores were assessed at regular intervals over the period of 4 years. Also the drug administration time, surgical time, operating room time were assessed for simultaneous and sequential cochlear implant surgery. Children with bilateral simultaneous implants fared significantly better with CAP, SIR, localization, speech noise and traffic noise scores than sequential bilateral implants and unilateral implants with a significant difference of means t tests between the two groups. Simultaneous cochlear implant surgery is associated with reduced surgical time, operating room time, it shortens the total in patient stay. There is less of drug administration and bilateral ones are stimulated simultaneously. Bilateral cochlear implants perform better with respect to auditory perception skills and spontaneous speech when compared with unilateral implants, but simultaneous surgery is better and safe option for pediatric cochlear implantation.

Benefit of sequential bilateral cochlear implantation in children between 5 to 18 years old: A prospective cohort study

Objective

To determine the benefit of sequential cochlear implantation after a long inter-implantation interval in children with bilateral deafness receiving their second implant between 5 and 18 years of age.

Study design

Prospective cohort-study.

Setting

Tertiary multicenter.

Patients

85 children with bilateral deafness and unilateral implantation receiving a contralateral cochlear implant at the age of 5 to 18 years.

Method

The primary outcomes were speech recognition in quiet and noise (CVC) scores. The secondary outcomes were language outcomes and subjective hearing abilities, all measured before and 12 months after sequential bilateral cochlear implantation. Medians of the paired data were compared using the Wilcoxon signed-rank test. Univariable linear regression analyses was used to analyze associations between variables and performance outcomes.

Results

A significant benefit was found for speech recognition in quiet (96% [89–98] vs 91% [85–96]; p < 0.01) and noise (65% [57–75] vs 54% [47–71]; p = 0.01) in the bilateral CI condition compared to unilateral (n = 75, excluded 10 non-users). No benefit was seen for language outcomes. The subjective sound quality score was statistically significant higher in bilateral compared to the unilateral CI condition. Pre-operative residual hearing level in the ear of the second implant, the inter-implant interval and age at time of second implantation was not significantly associated with performance scores.

Conclusion

After 12 months of use, sequential bilateral cochlear implantation showed improved speech perception in quiet and noise and improved subjective sound quality outcomes in children despite a great inter-implantation interval (median of 8 years [range 1–16 years]).

Wellbeing as Capability: Findings in Hearing-Impaired Adolescents and Young Adults With a Hearing Aid or Cochlear Implant

In the Western world, for deaf and hard-of-hearing children, hearing aids or cochlear implants are available to provide access to sound, with the overall goal of increasing their wellbeing. If and how this goal is achieved becomes increasingly multifarious when these children reach adolescence and young adulthood and start to participate in society in other ways. An approach to wellbeing that includes personal differences and the relative advantages and disadvantages that people have, is the capability approach, as developed by Nobel Prize laureate Amartya Sen. Capability is the set of real opportunities people have to do and be things they have reason to value. We interviewed 59 young people, aged 13 through 25, with cochlear implants (37) or hearing aids (22) to capture their capability. We found that their hearing devices enabled them to actively participate in a predominantly hearing society, with few differences between cochlear implant and hearing aid recipients. They did, however, report challenges associated with prejudices and expectations, and with feeling poorly understood, all of which appeared to impact their capability. Through the lens of capability, alleged differences between hearing aid and cochlear implant recipients began to fade. We discuss the implications for initiatives focused on the long-term support young recipients of hearing devices to meet their specific requirements over time.

Novel Approaches to Measure Spatial Release From Masking in Children With Bilateral Cochlear Implants

OBJECTIVES

To investigate the role of auditory cues for spatial release from masking (SRM) in children with bilateral cochlear implants (BiCIs) and compare their performance with children with normal hearing (NH). To quantify the contribution to speech intelligibility benefits from individual auditory cues: head shadow, binaural redundancy, and interaural differences; as well as from multiple cues: SRM and binaural squelch. To assess SRM using a novel approach of adaptive target-masker angular separation, which provides a more functionally relevant assessment in realistic complex auditory environments.

DESIGN

Children fitted with BiCIs (N = 11) and with NH (N = 18) were tested in virtual acoustic space that was simulated using head-related transfer functions measured from individual children with BiCIs behind the ear and from a standard head and torso simulator for all NH children. In experiment I, by comparing speech reception thresholds across 4 test conditions that varied in target-masker spatial separation (colocated versus separated at 180°) and listening conditions (monaural versus binaural/bilateral listening), intelligibility benefits were derived for individual auditory cues for SRM. In experiment II, SRM was quantified using a novel measure to find the minimum angular separation (MAS) between the target and masker to achieve a fixed 20% intelligibility improvement. Target speech was fixed at either +90 or -90° azimuth on the side closer to the better ear (+90° for all NH children) and masker locations were adaptively varied.

RESULTS

In experiment I, children with BiCIs as a group had smaller intelligibility benefits from head shadow than NH children. No group difference was observed in benefits from binaural redundancy or interaural difference cues. In both groups of children, individuals who gained a larger benefit from interaural differences relied less on monaural head shadow, and vice versa. In experiment II, all children with BiCIs demonstrated measurable MAS thresholds <180° and on average larger than that from NH children. Eight of 11 children with BiCIs and all NH children had a MAS threshold <90°, requiring interaural differences only to gain the target intelligibility benefit; whereas the other 3 children with BiCIs had a MAS between 120° and 137°, requiring monaural head shadow for SRM.

CONCLUSIONS

When target and maskers were separated at 180° on opposing hemifields, children with BiCIs demonstrated greater intelligibility benefits from head shadow and interaural differences than previous literature showed with a smaller separation. Children with BiCIs demonstrated individual differences in using auditory cues for SRM. From the MAS thresholds, more than half of the children with BiCIs demonstrated robust access to interaural differences without needing additional monaural head shadow for SRM. Both experiments led to the conclusion that individualized fitting strategies in the bilateral devices may be warranted to maximize spatial hearing for children with BiCIs in complex auditory environments.

Involving Children and Teenagers With Bilateral Cochlear Implants in the Design of the BEARS (Both EARS) Virtual Reality Training Suite Improves Personalization

Older children and teenagers with bilateral cochlear implants often have poor spatial hearing because they cannot fuse sounds from the two ears. This deficit jeopardizes speech and language development, education, and social well-being. The lack of protocols for fitting bilateral cochlear implants and resources for spatial-hearing training contribute to these difficulties. Spatial hearing develops with bilateral experience. A large body of research demonstrates that sound localisation can improve with training, underpinned by plasticity-driven changes in the auditory pathways. Generalizing training to non-trained auditory skills is best achieved by using a multi-modal (audio-visual) implementation and multi-domain training tasks (localisation, speech-in-noise, and spatial music). The goal of this work was to develop a package of virtual-reality games (BEARS, Both EARS) to train spatial hearing in young people (8–16 years) with bilateral cochlear implants using an action-research protocol. The action research protocol used formalized cycles for participants to trial aspects of the BEARS suite, reflect on their experiences, and in turn inform changes in the game implementations. This participatory design used the stakeholder participants as co-creators. The cycles for each of the three domains (localisation, spatial speech-in-noise, and spatial music) were customized to focus on the elements that the stakeholder participants considered important. The participants agreed that the final games were appropriate and ready to be used by patients. The main areas of modification were: the variety of immersive scenarios to cover age range and interests, the number of levels of complexity to ensure small improvements were measurable, feedback, and reward schemes to ensure positive reinforcement, and an additional implementation on an iPad for those who had difficulties with the headsets due to age or balance issues. The effectiveness of the BEARS training suite will be evaluated in a large-scale clinical trial to determine if using the games lead to improvements in speech-in-noise, quality of life, perceived benefit, and cost utility. Such interventions allow patients to take control of their own management reducing the reliance on outpatient-based rehabilitation. For young people, a virtual-reality implementation is more engaging than traditional rehabilitation methods, and the participatory design used here has ensured that the BEARS games are relevant.

Lateralization of interaural level differences in children with bilateral cochlear implants

OBJECTIVES

To investigate the perception of interaural level differences (ILDs) in children with bilateral cochlear implants (BiCIs) and compare them to normal hearing peers. As intracranial shifts in perception of ILDs might have an effect on localization, this was further investigated.

METHODS

ILD responses on four different frequency bands (broadband, low-pass, mid-pass and high-pass) were measured in 9 children with BiCIs and 15 children with normal hearing. In the children with BiCIs, 7 of them were implanted sequentially and 2 of them simultaneously. The outcomes were compared with the outcomes from a previous study on advanced localization using the same stimuli as in the current study. The effect of chronological age, inter-implant delay and preoperative residual hearing were also taken into account.

RESULTS

No significant differences in ILD responses between children with BiCIs and children with normal hearing were found. For broadband stimuli, children with sequential BiCIs showed a significant shift in their response towards the first implant. A significant correlation was found between inter-implant delay and shift in ILD response for the broadband and high-pass stimuli. The shift in ILD response had no effect on localization.

CONCLUSION

Children with BiCIs are able to perceive ILD responses similar to those of normal hearing children. The inter-implant delay has a negative effect on the lateralization of the response towards the first implant side, indicative of deprivation of high-frequency sounds prior to receiving a second implant. This shift, however, is not associated with a shift in localization response.

Bimodal Fitting and Bilateral Cochlear Implants in Children With Significant Residual Hearing: The Impact of Asymmetry in Spatial Release of Masking on Localization

Purpose This study aimed to gain more insight into the primary auditory abilities of children with significant residual hearing in order to improve decision making when choosing between bimodal fitting or sequential bilateral cochlear implantation. Method Sound localization abilities, spatial release of masking, and fundamental frequency perception were tested. Nine children with bimodal fitting and seven children with sequential bilateral cochlear implants were included in the study. As a reference, 15 children with normal hearing and two children with simultaneous bilateral cochlear implants were included. Results On all outcome measures, the implanted children performed worse than the normal hearing children. For high-frequency localization, children with sequential bilateral cochlear implants performed significantly better than children with bimodal fitting. Compared to children with normal hearing, the left-right asymmetry in spatial release of masking was significant. When the implant was hindered by noise, bimodally fitted children obtained significantly lower spatial release of masking compared to when the hearing aid was hindered by noise. Overall, the larger the left-right asymmetry in spatial release of masking, the poorer the localization skills. No significant differences were found in fundamental frequency perception between the implant groups. Conclusions The data hint to an advantage of bilateral implantation over bimodal fitting. The extent of asymmetry in spatial release of masking is a promising tool for decision making when choosing whether to continue with the hearing aid or to provide a second cochlear implant in children with significant residual hearing.

Sonority-Related Novel Word Learning Ability of Children With Cochlear Implants With Optimal Oral Language Exposure

OBJECTIVES

The present study investigated how children with cochlear implants (CIs), with optimal exposure to oral language, perform on sonority-related novel word learning tasks. By optimal oral language exposure, we refer to bilateral cochlear implantation below the age of 2 years. Sonority is the relative perceptual prominence/loudness of speech sounds of the same length, stress, and pitch. The present study is guided by a previous study that investigated the sonority-related novel word learning ability of a group of children with CIs, in the Greek language, of which the majority were implanted beyond the age of 2 unilaterally.

DESIGN

A case-control study with 15 Dutch-speaking participants in each of the three groups, i.e., children with CIs, normal-hearing children (NHC), and normal-hearing adults, was conducted using a sonority-related novel "CVC" word learning task. All children with CIs are implanted before the age of 2 years with preimplant hearing aids. Thirteen out of the 15 children had bilateral CIs. The CVC words were constructed according to four sonority conditions, where N is nonsonorous and S is a sonorous phoneme: NSN, NSS, SSN, and SSS. Outcome measures were accuracy and reaction times (RTs). In addition, the Peabody picture vocabulary test and the digit span forward test were administered to the children.

RESULTS

There were no statistical differences in accuracy or RTs between the children groups on the overall score and across the different conditions. However, children with CIs, unlike NHC, scored statistically less accurately and with longer RTs relative to normal-hearing adults, on the overall task. Within-group comparisons showed that none of the groups performed statistically differently on any of the conditions. The NHC showed higher receptive vocabulary scores relative to children with CIs. In addition, the group of children with CIs entailed a statistically significantly higher number of children with "weak" short-term memory.

CONCLUSIONS

Children with CIs who have optimal oral language exposure showed age-appropriate sonority-related novel word learning abilities and strategies relative to their NH peers. However, children with CIs continue to show lower receptive vocabulary scores than NHC, despite the equivalent novel word learning ability. This suggests that children with CIs may have difficulties in retaining newly learned words. Future work should look into possible causes of the gap in performance. This would eventually aid in rehabilitation tailored to the needs of the individual.

Meta-Analytic Findings on Reading in Children With Cochlear Implants

This meta-analysis study aims to quantify the group differences in reading skills between children with cochlear implants and their hearing peers and between children with cochlear implants and children with hearing aids (aged between 3 and 18 years old). Of the 5,642 articles screened, 47 articles met predetermined inclusion criteria (published between 2002 and 2019). The robust variance estimation based meta-analysis models were used to synthesize all the effect sizes. Children with cochlear implants scored significantly lower than their hearing peers in phonological awareness (g = -1.62, p < 0.001), vocabulary (g = -1.50, p < 0.001), decoding (g = -1.24, p < 0.001), and reading comprehension (g = -1.39, p < 0.001), but not for fluency (g = -0.67, p = 0.054). Compared to children with hearing aids, children with cochlear implants scored significantly lower in phonological awareness (g = -0.30, p = 0.028). The percentage of unilateral cochlear implant negatively impacts the group difference between children with cochlear implants and their hearing peers. Findings from this study confirm a positive shift in reading outcomes for profoundly deaf children due to cochlear implantation. Some children with cochlear implants may need additional supports in educational settings.

Cochlear Implantation

BACKGROUND

Hearing impairment that is too severe to be adequately treated with conventional hearing aids can lead, in children, to severe developmental disturbances of hearing and language, and, in adults, to communicative and social deprivation. Recent advances in medical device technology and in microsurgical techniques have led to an expansion of the indications for cochlear implantation (CI) for adults with progressive hearing loss in older age, and to a restructuring of the process of care for these patients in Germany.

METHODS

This review is based on pertinent publications retrieved by a selective search in PubMed, as well as on the CI guidelines and CI "white book" of the German Society of Otolaryngology and Head and Neck Surgery.

RESULTS

Early and accurate diagnosis is crucial for the successful auditory rehabilitation of high-grade hearing impairment. In children, a key role is played by newborn auditory screening, which is mandatory in Germany and enables the provision of a CI in the first year of life when necessary. 86% of the children receiving a CI achieve linguistic comprehension of fluently spoken sentences. For adults, positive prognostic factors for hearing after the provision of a CI include a highly motivated patient, "postlingual" onset of the hearing impairment (i.e., after the acquisition of language), and a brief duration of deafness. Auditory rehabilitation is associated with significant improvement, not just of hearing and of the comprehension of spoken language, but also of quality of life, particularly in elderly patients. For patients of any age with bilateral hearing loss, CIs should be provided on both sides, if possible. The more common complications of the procedure, with a probability of 2-4% each, are technical implant defects, dizziness, and wound-healing disturbances.

CONCLUSION

Cochlear implantation, performed in specialized centers, is a safe and reliable technique and regularly enables the successful rehabilitation of hearing in both children and adults.

Self-concept of children and adolescents with cochlear implants

OBJECTIVES

Communicative disorders can complicate social interactions and may be detrimental for one's self-concept. This study aims to assess the self-concept of children with Cochlear Implants (CI). Results of educational peer groups (special needs or typical) were compared. Correlations amongst speech perception, language comprehension, self-concept and other study variables are determined.

METHODS

This retrospectively patient file study contained 53 CI participants with a mean age of 14.2 (SD = 2.8). Self-concept was measured with the Dutch language version of the Self-Perception Profile for Children and Adolescents. Proportions of low, normal and high competence scores were compared to a normative sample. Outcomes were analyzed for the total CI group and for the two educational peer groups.

RESULTS

In the Scholastic Competence, Athletic Competence, Physical Appearance and Behavioral Conduct domains larger proportions of high perceived competence levels were found in the CI Total group compared to the hearing normative sample. Children with CIs in the Mainstream educational subgroup were found to have larger proportions of high levels on these domains. Remarkably, children with CI in the Special hearing impaired educational subgroup reported comparable self-concept scores as their hearing peers. Speech perception and language comprehension were positively correlated to Scholastic Competence.

CONCLUSION

This study has shown that self-concept levels of profoundly hearing impaired children with CI are comparable to those of hearing peers. They are generally satisfied with their functioning in various domains. Better speech perception and language comprehension levels are related to higher outcomes in the Scholastic Competence domain.

Capability of deaf children with a cochlear implant

INTRODUCTION

The main idea underlying this paper is that impairments such as deafness are particularly relevant to the extent that they lead to deprivation of capability. Likewise, the impact of healthcare services such as cochlear implants and subsequent rehabilitation can best be inferred from the extent that they protect or restore capability of those affected.

METHODS

To explore children's post-implant capabilities, we tested two newly developed digital, adaptive child self-report and parent-report questionnaires in 19 deaf children (aged 8-12 years) and their parents during rehabilitation, as well as in 23 age peers with normal hearing.

RESULTS

Despite the impressive speech-language results that were recorded with cochlear implants, the post-implant capabilities of the deaf children we evaluated differed from those of their hearing peers, with the cochlear implant group appearing particularly disadvantaged in areas such as accessing information, communication, social participation, and participation in school.

CONCLUSION

Deaf children with cochlear implants who are performing well on linguistic and auditory tests can still experience serious limitations in desired functioning. Our findings suggest that a capability approach may reveal aspects of what is being achieved through rehabilitation that might otherwise remain unnoticed, and that could help to further improve the well-being of our patients.IMPLICATIONS FOR REHABILITATIONOverall, children with cochlear implants appeared disadvantaged in certain capability areas, like accessing information, communication, social participation, and participation in school.It may be worthwhile to also ascertain capabilities in these children, representing a domain not covered by clinical measures, tapping directly into areas that are valuable to the patient.

Personality Traits of Profoundly Hearing Impaired Adolescents with Cochlear Implants - A Comparison with Normal Hearing Peers

The aim of this study was to compare the personality traits of adolescents with cochlear implants (CIs) to a reference group (normal-hearing peers). In the past, the personality development of hearing impaired adolescents was severely compromised. Improved speech perception with CI significantly increased their perspectives. In addition, differences between the reference group and CI users were investigated on personality traits according to level of speech perception skills (high/low) and level of language comprehension (adequate/poor). A cohort of 59 adolescents was assessed 10 years after CI implantation. Personality traits were measured using the standardized Dutch Personality Questionnaire, which consists of 5 scales: Inadequacy, Social Inadequacy, Recalcitrance (RE), Perseverance, and Dominance. Speech perception and language comprehension were tested with standardized tests. The distributions of personality scores, in the clinical or non-clinical range, for the CI group were compared to the reference group using the Chi-Square test for Goodness of Fit. Adolescents with CI showed normal or favorable distributions on all personality scales except for the RE scale. There was a significant influence of speech perception and language comprehension on this scale. Consequently, adolescents with CI who demonstrated high speech perception and adequate language comprehension scores showed similar distribution patterns as the reference group on all personality scales. In conclusion; personality traits that reflect social relations, self-conscience, and school- and task orientation in adolescents with CI are similar to those in normal-hearing peers. This holds, despite variations in speech perception ability and language comprehension levels, for the CI group. On the RE scale, the adolescents with CI with low speech perception and poor language comprehension scores are more likely to score in the clinical deviant range and are at risk.

Perceived improvements and challenges following sequential bilateral cochlear implantation in children and adults

OBJECTIVE

Semi-structured interviews were conducted with sequentially implanted bilateral cochlear-implant (biCI) recipients to examine functional aspects of communication that are affected by listening with one versus two CIs.

DESIGN

Participants were 15 adult biCI recipients and parents of 30 children (categorized into three groups by age) with biCIs. All CI users had sequential placement of biCIs with at least six months' experience with the first CI before activation of the second device, and at least three months' experience with both CIs prior to the interview. The parent/paediatric and adult interviews were all conducted by the same examiner. Electronic transcripts of the interview responses were coded for perceived changes or lack thereof in 23 behaviours following biCI. Extent of reported benefit was quantified for each subject within and across these behaviours and at the group level as a function of age.

RESULTS

Most adults and parents of children reported multiple functional changes following biCI use, and changes often translated to enhanced social communication. Nearly all participants were consistent users of biCIs, and were satisfied with their perceived gains in communicating in everyday settings. Most reported ongoing challenges listening in noisy settings. Although many reports on children paralleled those of adults, developmental differences were apparent. Thirteen percent of adults and twenty percent of parents of children in each of the respective groups reported low levels of change.

CONCLUSIONS

Results suggest that many biCI users experience meaningful functional benefits that may be underestimated by traditional outcome measures. We suggest the need to expand measurement approaches to better quantify the nature of these benefits.

United Kingdom national paediatric bilateral project: Demographics and results of localization and speech perception testing

OBJECTIVES

To assess longitudinal outcomes in a large and varied population of children receiving bilateral cochlear implants both simultaneously and sequentially.

METHODS

This observational non-randomized service evaluation collected localization and speech recognition in noise data from simultaneously and sequentially implanted children at four time points: before bilateral cochlear implants or before the sequential implant, 1 year, 2 years, and 3 years after bilateral implants. No inclusion criteria were applied, so children with additional difficulties, cochleovestibular anomalies, varying educational placements, 23 different home languages, a full range of outcomes and varying device use were included.

RESULTS

1001 children were included: 465 implanted simultaneously and 536 sequentially, representing just over 50% of children receiving bilateral implants in the UK in this period. In simultaneously implanted children the median age at implant was 2.1 years; 7% were implanted at less than 1 year of age. In sequentially implanted children the interval between implants ranged from 0.1 to 14.5 years. Children with simultaneous bilateral implants localized better than those with one implant. On average children receiving a second (sequential) cochlear implant showed improvement in localization and listening in background noise after 1 year of bilateral listening. The interval between sequential implants had no effect on localization improvement although a smaller interval gave more improvement in speech recognition in noise. Children with sequential implants on average were able to use their second device to obtain spatial release from masking after 2 years of bilateral listening. Although ranges were large, bilateral cochlear implants on average offered an improvement in localization and speech perception in noise over unilateral implants.

CONCLUSION

These data represent the diverse population of children with bilateral cochlear implants in the UK from 2010 to 2012. Predictions of outcomes for individual patients are not possible from these data. However, there are no indications to preclude children with long inter-implant interval having the chance of a second cochlear implant.

Semantic and syntactic reading comprehension strategies used by deaf children with early and late cochlear implantation

Deaf students have traditionally exhibited reading comprehension difficulties. In recent years, these comprehension problems have been partially offset through cochlear implantation (CI), and the subsequent improvement in spoken language skills. However, the use of cochlear implants has not managed to fully bridge the gap in language and reading between normally hearing (NH) and deaf children, as its efficacy depends on variables such as the age at implant. This study compared the reading comprehension of sentences in 19 children who received a cochlear implant before 24 months of age (early-CI) and 19 who received it after 24 months (late-CI) with a control group of 19 NH children. The task involved completing sentences in which the last word had been omitted. To complete each sentence children had to choose a word from among several alternatives that included one syntactic and two semantic foils in addition to the target word. The results showed that deaf children with late-CI performed this task significantly worse than NH children, while those with early-CI exhibited no significant differences with NH children, except under more demanding processing conditions (long sentences with infrequent target words). Further, the error analysis revealed a preference of deaf students with early-CI for selecting the syntactic foil over a semantic one, which suggests that they draw upon syntactic cues during sentence processing in the same way as NH children do. In contrast, deaf children with late-CI do not appear to use a syntactic strategy, but neither a semantic strategy based on the use of key words, as the literature suggests. Rather, the numerous errors of both kinds that the late-CI group made seem to indicate an inconsistent and erratic response when faced with a lack of comprehension. These findings are discussed in relation to differences in receptive vocabulary and short-term memory and their implications for sentence reading comprehension.

Morpho-syntactic reading comprehension in children with early and late cochlear implants

This study explores morpho-syntactic reading comprehension in 19 Spanish children who received a cochlear implant (CI) before 24 months of age (early CI [e-CI]) and 19 Spanish children who received a CI after 24 months (late CI [l-CI]). They all were in primary school and were compared to a hearing control (HC) group of 19 children. Tests of perceptual reasoning, working memory, receptive vocabulary, and morpho-syntactic comprehension were used in the assessment. It was observed that while children with l-CI showed a delay, those with e-CI reached a level close to that which was obtained by their control peers in morpho-syntactic comprehension. Thus, results confirm a positive effect of early implantation on morpho-syntactic reading comprehension. Inflectional morphology and simple sentence comprehension were noted to be better in the e-CI group than in the l-CI group. The most important factor in distinguishing between the HC and l-CI groups or the e-CI and l-CI groups was verbal inflectional morphology.