Evidence-Based Approach for Making Cochlear Implant Recommendations for Infants With Residual Hearing

Prognostic Value of Electrophysiological and MRI Findings for Pediatric Cochlear Implant Outcomes: A Systematic Review

PURPOSE

Magnetic resonance imaging (MRI), electric compound action potential (eCAP), and electric auditory brainstem response (eABR) are among the routine assessments performed before and/or after cochlear implantation. The objective of this review was to systematically summarize and critically appraise existing evidence of the prognostic value of eCAP, eABR, and MRI for predicting post-cochlear implant (CI) speech perception outcomes in children, with a particular focus on the lesion site.

METHOD

The present systematic review was conducted according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses 2020 statement. Three electronic databases (ProQuest, PubMed, and Scopus) were searched with no restrictions on language, publication status, or year of publication. Studies on children identified with sensorineural hearing loss, auditory neuropathy spectrum disorder, cochlear nerve deficiency, or cochleovestibular nerve abnormalities reporting the relevance of eCAP, eABR, and/or MRI results to CI speech perception outcomes were included. The literature search yielded 1,887 publications. Methodological quality and strength of evidence were assessed by the Crowe Critical Appraisal Tool and the Grading of Recommendations Assessment, Development, and Evaluation tool, respectively.

RESULTS

Of the 25 included studies, the relevance of eCAP, eABR, and/or MRI findings to post-CI speech perception outcomes was reported in 10, 11, and 11 studies, respectively. The studies were strongly in support of the prognostic value of eABR and MRI for CI outcomes. However, the relevance of eCAP findings to speech perception outcomes was uncertain.

CONCLUSION

Despite the promising findings, caution is warranted in interpreting them due to the observational and retrospective design of the included studies, as well as the heterogeneity of the population and the limited control of confounding factors within these studies.

SUPPLEMENTAL MATERIAL

https://doi.org/10.23641/asha.26169859.

[Indications for Cochlear Implants in Children: Where is the Journey Heading?]

The indications for cochlear implants in children were gradually expended during the last 30 years. This concerns both the age at implantation and the audiological criteria, unilateral or bilateral treatment, the treatment of unilateral deafness and of children with multiple disabilities. Due to the improvement in hearing preservation and new technical developments, it is to be expected that the indication limits will continue to shift in the coming decades.

Benefits and risks related to cochlear implantation for children with residual hearing: a systematic review

OBJECTIVE

This study aimed to synthesise information concerning the potential benefits and risks related to cochlear implants (CIs) versus hearing aids (HAs) in children with residual hearing.

DESIGN

A systematic review of articles published from January 2003 to January 2019 was conducted.

STUDY SAMPLE

Our review included studies that compared the benefits and risks of CIs versus HAs in children (≤18 years old) with residual hearing. A total of 3265 citations were identified; 8 studies met inclusion criteria.

RESULTS

Children with CIs showed significantly better speech perception scores post-CI than pre-CI. There was limited evidence related to improvement in everyday auditory performance, and the results showed non-significant improvement in speech intelligibility. One study on social-emotional functioning suggested benefits from CIs. In four studies, 37.2% (16/43) of children showed loss of residual hearing and 14.0% (8/57) had discontinued or limited use of their device.

CONCLUSIONS

Children with CIs showed improvement in speech perception outcomes compared to those with HAs. However, due to the limited number of studies and information to guide decision-making related to other areas of development, it will be important to conduct further research of both benefits and risks of CIs in this specific population to facilitate decision-making.

Determining cochlear implant candidacy in children with residual hearing: A scoping review

OBJECTIVES

The purpose of this review was to summarize what is known about criteria, assessments, and recommendations for evaluating cochlear implant (CI) candidacy in children with residual hearing.

METHODS

Peer-reviewed studies were identified through a systematic search in five electronic databases. Articles were screened and assessed for eligibility. From the eligible studies, data were extracted to summarize and present a narrative synthesis of the findings.

RESULTS

A total of seven articles (two reviews and five primary studies) were included in the final analysis. Hearing levels better than the moderately severe to severe range (65-90 dB HL) tend to be supported as audiological candidacy criteria for pediatric CI. Recommendations for candidacy consideration based on audiologic thresholds range from 65 to 80 dB Hl pure-tone average as the lower boundary. Our review did not identify any specific assessment protocols. However, additional decision-making considerations related to borderline hearing loss configurations and assessment tools (the Speech Intelligibility Index and the Pediatric Minimum Speech Test Battery) were identified. Supplementary assessment considerations were also reported.

CONCLUSION

There is limited information regarding specific assessment protocols for children with residual hearing. The literature is primarily focused on guidelines related to audiologic criteria, although it is widely recommended that other areas of functioning should also be considered. Most recommendations appear to be based on expert opinion, clinical expertise, and evidence from overall pediatric CI outcomes rather than empirical evidence targeting children with residual hearing. There is an ongoing need for research to further develop protocols and tools that can assist clinicians and families in making cochlear implantation decisions for children with residual hearing.

Variability in Cochlear Implantation Outcomes in a Large German Cohort With a Genetic Etiology of Hearing Loss

OBJECTIVES

The variability in outcomes of cochlear implantation is largely unexplained, and clinical factors are not sufficient for predicting performance. Genetic factors have been suggested to impact outcomes, but the clinical and genetic heterogeneity of hereditary hearing loss makes it difficult to determine and interpret postoperative performance. It is hypothesized that genetic mutations that affect the neuronal components of the cochlea and auditory pathway, targeted by the cochlear implant (CI), may lead to poor performance. A large cohort of CI recipients was studied to verify this hypothesis.

DESIGN

This study included a large German cohort of CI recipients (n = 123 implanted ears; n = 76 probands) with a definitive genetic etiology of hearing loss according to the American College of Medical Genetics (ACMG)/Association for Molecular Pathology (AMP) guidelines and documented postoperative audiological outcomes. All patients underwent preoperative clinical and audiological examinations. Postoperative CI outcome measures were based on at least 1 year of postoperative audiological follow-up for patients with postlingual hearing loss onset (>6 years) and 5 years for children with congenital or pre/perilingual hearing loss onset (≤6 years). Genetic analysis was performed based on three different methods that included single-gene screening, custom-designed hearing loss gene panel sequencing, targeting known syndromic and nonsyndromic hearing loss genes, and whole-genome sequencing.

RESULTS

The genetic diagnosis of the 76 probands in the genetic cohort involved 35 genes and 61 different clinically relevant (pathogenic, likely pathogenic) variants. With regard to implanted ears (n = 123), the six most frequently affected genes affecting nearly one-half of implanted ears were GJB2 (21%; n = 26), TMPRSS3 (7%; n = 9), MYO15A (7%; n = 8), SLC26A4 (5%; n = 6), and LOXHD1 and USH2A (each 4%; n = 5). CI recipients with pathogenic variants that influence the sensory nonneural structures performed at or above the median level of speech performance of all ears at 70% [monosyllable word recognition score in quiet at 65 decibels sound pressure level (SPL)]. When gene expression categories were compared to demographic and clinical categories (total number of compared categories: n = 30), mutations in genes expressed in the spiral ganglion emerged as a significant factor more negatively affecting cochlear implantation outcomes than all clinical parameters. An ANOVA of a reduced set of genetic and clinical categories (n = 10) identified five detrimental factors leading to poorer performance with highly significant effects ( p < 0.001), accounting for a total of 11.8% of the observed variance. The single strongest category was neural gene expression accounting for 3.1% of the variance.

CONCLUSIONS

The analysis of the relationship between the molecular genetic diagnoses of a hereditary etiology of hearing loss and cochlear implantation outcomes in a large German cohort of CI recipients revealed significant variabilities. Poor performance was observed with genetic mutations that affected the neural components of the cochlea, supporting the "spiral ganglion hypothesis."

An Umbrella Review of Cochlear Implant Outcomes in Children With Auditory Neuropathy

PURPOSE

The objective of this overview of systematic reviews (SRs; umbrella review) was to systematically summarize and critically appraise current evidence of cochlear implant (CI) outcomes in children with auditory neuropathy spectrum disorder (ANSD).

METHOD

This study was guided by the Preferred Reporting Items for Systematic Reviews and Meta-Analyses 2020 statement. The methodological quality and the risk of bias in the included SRs were assessed using A MeaSurement Tool to Assess systematic Reviews 2 checklist and the Risk of Bias in Systematic Reviews tool, respectively.

RESULTS

According to eight included SRs, children with ANSD achieve CI outcomes (speech perception performance) similar to their peers with sensorineural hearing loss. In children with postsynaptic ANSD (cochlear nerve deficiency), cochlear nerve hypoplasia is associated with better speech recognition outcomes compared with cochlear nerve aplasia, especially in the absence of additional disabilities. Except for one study, the overall quality of the included SRs was critically low, and except for three studies, evidence of a high risk of bias was identified in other included SRs.

CONCLUSIONS

Current evidence supports CI benefits for children with ANSD. To improve the quality of evidence, well-designed, prospective studies with appropriate sample sizes, using valid outcome measures, clarifying matching criteria, and taking into account the role of confounding factors are essential.

Cochlear Implant Decision Making for Children With Residual Hearing: Perspectives of Practitioners

PURPOSE

Cochlear implants (CIs) are increasingly considered for children with residual hearing who benefit from hearing aids (HAs). However, the decision-making process for families of these children and for practitioners is particularly challenging because there is no clear audiological cut point for CI candidacy. This study aimed to understand Canadian practitioners' perspectives of the CI decision-making process and how they guide families of children with residual hearing.

METHOD

Semistructured interviews were conducted with a total of 17 practitioners through four focus groups and one individual interview. Interviews were transcribed verbatim, and a thematic analysis was carried out.

RESULTS

Data were organized into five broad domains: candidacy issues for children with residual hearing, practitioners' roles in decision support, additional considerations affecting decision making, factors facilitating decision making, and practitioners' needs.

CONCLUSIONS

This study found that practitioners' confidence in determining candidacy and supporting parents has increased due to their experiences with positive outcomes for these children. Practitioners indicated that there was a need for more research to guide the decision-making process.

The feasibility of cochlear implantation in early infancy

OBJECTIVES

To determine the key image anatomical parameters that are relevant to cochlear implantation (CI) using temporal bone high-resolution computed tomography (HRCT) scans and to identify age group differences in order to provide image anatomical support for early CI.

METHODS

The data of 346 temporal bone HRCTs of 173 children from 5 months to 18 years of age were retrospectively selected and reviewed. Parameters of the human temporal bone that are relevant to CI key surgical steps include mastoid thickness (MT), the facial recess width (FRW), and an angle representing the round window visibility. All measurements are performed on axial images.

RESULTS

There was no significant difference in the above morphological values by gender (p > 0,05). Two-sided FRW was not significantly different (p > 0,05), but MT and angle A were significantly different (p < 0,001). FRW and angle were independent of age (p > 0,05). However, MT had been found to exhibit postnatal development. The linear function of MT were calculated as y = 2463 × group(s) + 20,574 (p < 0,001).

CONCLUSIONS

Based on preoperative imaging analysis at different ages, middle ear development was stable at 5 months of age, allowing early CI in infancy with severe to severe hearing loss at this age. These data must be considered exploratory and more extensive clinical studies are needed.

Genetic etiological analysis of auditory neuropathy spectrum disorder by next-generation sequencing

Objective

Auditory neuropathy spectrum disease (ANSD) is caused by both environmental and genetic causes and is defined by a failure in peripheral auditory neural transmission but normal outer hair cells function. To date, 13 genes identified as potentially causing ANSD have been documented. To study the etiology of ANSD, we collected 9 probands with ANSD diagnosed in the clinic and performed targeted next-generation sequencing.

Methods

Nine probands have been identified as ANSD based on the results of the ABR tests and DPOAE/CMs. Genomic DNA extracted from their peripheral blood was examined by next-generation sequencing (NGS) for a gene panel to identify any potential causal variations. For candidate pathogenic genes, we performed co-segregation among all family members of the pedigrees. Subsequently, using a mini-gene assay, we examined the function of a novel splice site mutant of OTOF.

Results

We analyzed nine cases of patients with ANSD with normal CMs/DPOAE and abnormal ABR, discovered three novel mutants of the OTOF gene that are known to cause ANSD, and six cases of other gene mutations including TBC1D24, LARS2, TIMM8A, MITF, and WFS1.

Conclusion

Our results extend the mutation spectrum of the OTOF gene and indicate that the genetic etiology of ANSD may be related to gene mutations of TBC1D24, LARS2, TIMM8A, MITF, and WFS1.

Development of Sound Localization in Infants and Young Children with Cochlear Implants

Cochlear implantation as a treatment for severe-to-profound hearing loss allows children to develop hearing, speech, and language in many cases. However, cochlear implants are generally provided beyond the infant period and outcomes are assessed after years of implant use, making comparison with normal development difficult. The aim was to study whether the rate of improvement of horizontal localization accuracy in children with bilateral implants is similar to children with normal hearing. A convenience sample of 20 children with a median age at simultaneous bilateral implantation = 0.58 years (0.42−2.3 years) participated in this cohort study. Longitudinal follow-up of sound localization accuracy for an average of ≈1 year generated 42 observations at a mean age = 1.5 years (0.58−3.6 years). The rate of development was compared to historical control groups including children with normal hearing and with relatively late bilateral implantation (≈4 years of age). There was a significant main effect of time with bilateral implants on localization accuracy (slope = 0.21/year, R2 = 0.25, F = 13.6, p < 0.001, n = 42). No differences between slopes (F = 0.30, p = 0.58) or correlation coefficients (Cohen’s q = 0.28, p = 0.45) existed when comparing children with implants and normal hearing (slope = 0.16/year since birth, p = 0.015, n = 12). The rate of development was identical to children implanted late. Results suggest that early bilateral implantation in children with severe-to-profound hearing loss allows development of sound localization at a similar age to children with normal hearing. Similar rates in children with early and late implantation and normal hearing suggest an intrinsic mechanism for the development of horizontal sound localization abilities.

The Impact of Hearing Aids on Speech Perception in Mandarin-Speaking Children

Background. Severe hearing loss can affect speech perception in children, and hearing aids as a medical device may help improve speech perception in children. Objective. To explore the effects of fitting hearing aids (HAs) on speech perception in children with severe hearing loss (60–70 dB HL). Methods. Ninety-five children with bilateral severe hearing loss who were fitted bilaterally with HAs before the age of 3 years were followed up. The subjects were grouped according to their age at the time of fitting, i.e., <1, 1–2 , and 2–3 years groups. The Mandarin Early Speech Perception test was used to evaluate speech perception of Mandarin monosyllabic words at 12, 24, and 36 months after fitting. Results. There were significant improvements in vowel, consonant, and tone perception scores from 12 to 36 months after fitting HAs in the three age groups, and the mean score at 36 months after fitting was significantly improved at >85%. The mean speech pattern and spondee perception scores averaged at >90% at 12 months after fitting and were comparable to the scores of 2-year-old children with normal hearing. Conclusions. HA helps with speech perception in children with severe hearing loss.

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%.

American Cochlear Implant Alliance Task Force Guidelines for Determining Cochlear Implant Candidacy in Children

This article summarizes the available evidence on pediatric cochlear implantation to provide current guidelines for clinical protocols and candidacy recommendations in the United States. Candidacy determination involves specification of audiologic and medical criteria per guidelines of the Food and Drug Administration. However, recommendations for a cochlear implant evaluation also should maintain flexibility and consider a child’s skill progression (i.e., month-for-month progress in speech, language, and auditory development) and quality of life with appropriately fit hearing aids. Moreover, evidence supports medical and clinical decisions based on other factors, including (a) ear-specific performance, which affords inclusion of children with asymmetric hearing loss and single-sided deafness as implant candidates; (b) ear-specific residual hearing, which influences surgical technique and device selection to optimize hearing; and (c) early intervention to minimize negative long-term effects on communication and quality of life related to delayed identification of implant candidacy, later age at implantation, and/or limited commitment to an audiologic rehabilitation program. These evidence-based guidelines for current clinical protocols in determining pediatric cochlear implant candidacy encourage a team-based approach focused on the whole child and the family system.

A Scoping Review of Studies Comparing Outcomes for Children With Severe Hearing Loss Using Hearing Aids to Children With Cochlear Implants

OBJECTIVES

Clinical practice regarding children's candidature for cochlear implantation varies internationally, albeit with a recent global trend toward implanting children with more residual hearing than in the past. The provision of either hearing aids or cochlear implants can influence a wide range of children's outcomes. However, guidance on eligibility and suitability for implantation is often based on a small number of studies and a limited range of speech perception measures. No recent reviews have catalogued what is known about comparative outcomes for children with severe hearing-loss using hearing aids to children using cochlear implants. This article describes the findings of a scoping review that addressed the question "What research has been conducted comparing cochlear implant outcomes to outcomes in children using hearing aids with severe hearing-loss in the better-hearing ear?" The first objective was to catalogue the characteristics of studies pertinent to these children's candidature for cochlear implantation, to inform families, clinicians, researchers, and policy-makers. The second objective was to identify gaps in the evidence base, to inform future research projects and identify opportunities for evidence synthesis.

DESIGN

We included studies comparing separate groups of children using hearing aids to those using cochlear implants and also repeated measures studies comparing outcomes of children with severe hearing loss before and after cochlear implantation. We included any outcomes that might feasibly be influenced by the provision of hearing aids or cochlear implants. We searched the electronic databases Medline, PubMed, and CINAHL, for peer-reviewed journal articles with full-texts written in English, published from July 2007 to October 2019. The scoping methodology followed the approach recommended by the Joanna Briggs Institute regarding study selection, data extraction, and data presentation.

RESULTS

Twenty-one eligible studies were identified, conducted across 11 countries. The majority of children studied had either congenital or prelingual hearing loss, with typical cognitive function, experience of spoken language, and most implanted children used one implant. Speech and language development and speech perception were the most frequently assessed outcomes. However, some aspects of these outcomes were sparsely represented including voice, communication and pragmatic skills, and speech perception in complex background noise. Two studies compared literacy, two sound localization, one quality of life, and one psychosocial outcomes. None compared educational attainment, listening fatigue, balance, tinnitus, or music perception.

CONCLUSIONS

This scoping review provides a summary of the literature regarding comparative outcomes of children with severe hearing-loss using acoustic hearing aids and children using cochlear implants. Notable gaps in knowledge that could be addressed in future research includes children's quality of life, educational attainment, and complex listening and language outcomes, such as word and sentence understanding in background noise, spatial listening, communication and pragmatic skills. Clinician awareness of this sparse evidence base is important when making management decisions for children with more residual hearing than traditional implant candidates. This review also provides direction for researchers wishing to strengthen the evidence base upon which clinical decisions can be made.

Prelinguistic Vocal Development in Children With Cochlear Implants: A Systematic Review

OBJECTIVES

This systematic review is designed to (a) describe measures used to quantify vocal development in pediatric cochlear implant (CI) users, (b) synthesize the evidence on prelinguistic vocal development in young children before and after cochlear implantation, and (c) analyze the application of the current evidence for evaluating change in vocal development before and after cochlear implantation for young children. Investigations of prelinguistic vocal development after cochlear implantation are only beginning to uncover the expected course of prelinguistic vocal development in children with CIs and what factors influence that course, which varies substantially across pediatric CI users. A deeper understanding of prelinguistic vocal development will improve professionals' abilities to determine whether a child with a CI is exhibiting sufficient progress soon after implantation and to adjust intervention as needed.

DESIGN

We systematically searched PubMed, ProQuest, and CINAHL databases for primary reports of children who received a CI before 5 years 0 months of age that included at least one measure of nonword, nonvegetative vocalizations. We also completed supplementary searches.

RESULTS

Of the 1916 identified records, 59 met inclusion criteria. The included records included 1125 total participants, which came from 36 unique samples. Records included a median of 8 participants and rarely included children with disabilities other than hearing loss. Nearly all of the records met criteria for level 3 for quality of evidence on a scale of 1 (highest) to 4 (lowest). Records utilized a wide variety of vocalization measures but often incorporated features related to canonical babbling. The limited evidence from pediatric CI candidates before implantation suggests that they are likely to exhibit deficits in canonical syllables, a critical vocal development skill, and phonetic inventory size. Following cochlear implantation, multiple studies report similar patterns of growth, but faster rates producing canonical syllables in children with CIs than peers with comparable durations of robust hearing. However, caution is warranted because these demonstrated vocal development skills still occur at older chronological ages for children with CIs than chronological age peers with typical hearing.

CONCLUSIONS

Despite including a relatively large number of records, the evidence in this review regarding changes in vocal development before and after cochlear implantation in young children remains limited. A deeper understanding of when prelinguistic skills are expected to develop, factors that explain deviation from that course, and the long-term impacts of variations in vocal prelinguistic development is needed. The diverse and dynamic nature of the relatively small population of pediatric CI users as well as relatively new vocal development measures present challenges for documenting and predicting vocal development in pediatric CI users before and after cochlear implantation. Synthesizing results across multiple institutions and completing rigorous studies with theoretically motivated, falsifiable research questions will address a number of challenges for understanding prelinguistic vocal development in children with CIs and its relations with other current and future skills. Clinical implications include the need to measure prelinguistic vocalizations regularly and systematically to inform intervention planning.

Factors affecting phoneme discrimination in children with sequential bilateral cochlear implants

OBJECTIVES

To investigate the effects of a number of variables on phoneme discrimination (PD) performance in children with sequential bilateral cochlear implants (SeqBiCIs) and compare PD performance between the 2 implantation sides and between children with bilateral cochlear implants (BiCIs) and their age-matched peers with normal hearing (NH).

DESIGN

All participants completed the Auditory Speech Sound Evaluation Phoneme Discrimination Test.

STUDY SAMPLE

The sample included 23 children with SeqBiCIs as the study group and 23 with NH as the control group.

RESULTS

A significant difference was found between the scores of the two groups under the CI₁ and CI₂ conditions (p = 0.001), CI₁ and BiCI conditions (p = 0.002), and CI₂ and BiCI conditions (p = 0.001). PD scores with CI₁ significantly depend on age at CI₁ and duration of bilateral use. PD scores with CI₁ were significant predictors of PD performance with CI₂. Duration of BiCI use was a significant predictor of PD scores with BiCI.

CONCLUSIONS

The age at CI₁ and the duration of bilateral cochlear implant use were found to improve phoneme discrimination performance in children with a sequential bilateral cochlear implant. According to the success of the CI₁, it is possible to predict the success of CI₂ use.

Clinical characteristics and outcomes of children with cochlear implants who had preoperative residual hearing

OBJECTIVE

Cochlear implants (CI) candidacy criteria have expanded to include children with more residual hearing. This study explored the clinical profiles and outcomes of children with CIs who had preoperative residual hearing in at least one ear.

DESIGN

A retrospective chart review was conducted to collect clinical characteristics and speech perception data. Pre- and post-CI auditory and speech perception data were analysed using a modified version of the Pediatric Ranked Order Speech Perception (PROSPER) score.

STUDY SAMPLE

This study included all children with residual hearing who received CIs in one Canadian paediatric centre from 1992 to 2018.

RESULTS

A total of 100 of 389 (25.7%) children with CIs had residual hearing (median 77.6 dB HL, better ear). The proportion of children with residual hearing increased from 1992 to 2018. Children who had auditory behaviour and speech perception tests (n = 83) showed higher modified PROSPER scores post-CI compared to pre-CI. Phonologically Balanced Kindergarten (PBK) test scores were available for 71 children post-CI; 81.7% (58/71) of children achieved > 80% on the PBK.

CONCLUSIONS

One in four children who received CIs had residual hearing, and most of them had severe hearing loss at pre-CI. These children showed a high level of speech perception with CIs.

Speech Perception and Language Outcomes for Infants Receiving Cochlear Implants Before or After 9 Months of Age: Use of Category-Based Aggregation of Data in an Unselected Pediatric Cohort

Purpose This retrospective study aimed to amass large data sets to enable statistical comparisons of communication outcomes for infants receiving cochlear implants (CIs) before 9 months of age compared to groups who received their first CI between 9 months and 3.5 years of age. Method Speech perception scores and experienced clinicians' observations were used to refine the Categories of Auditory Performance Index (CAPI), thus creating its revised version, namely, the CAPI-Revised (CAPI-R). Standardized and criterion-referenced language data were used to create the novel Categories of Linguistic Performance (CLIP). The association between CAPI-R and CLIP data at two time points post implant (at 2 years of device experience and at 5 years of age) was examined in a large unselected cohort stratified for age at first implant: before 9 months (Group 1), between 9 and 12 months (Group 2), between 13 and 18 months (Group 3), between 19 and 24 months (Group 4), between 25 and 30 months (Group 5), between 31 and 36 months (Group 6), and between 37 and 42 months (Group 7). Results CAPI-R medians were 5 at 2 years of device experience, and 6 at 5 years of age. At 2 years of device experience, there was no significant difference in CAPI-R medians for children who received their first CI before 9 months compared to all other age-at-implant groups. At 5 years of age, a significantly better CAPI-R median was demonstrated by Group 1 (CI before 9 months) compared to Groups 4, 5, 6, and 7. CLIP medians were 3 at 2 years of device experience, and at 5 years of age. At 2 years device experience, and at 5 years of age, the Group 1 CLIP medians were significantly better than later age-at-implant groups. Conclusion Median CAPI-R outcomes supported access to CIs before 18 months of age for speech perception, and median CLIP outcomes supported access to CIs before 9 months of age for optimum language development.

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.

Hearing Loss in Children: A Review

IMPORTANCE

Hearing loss in children is common and by age 18 years, affects nearly 1 of every 5 children. Without hearing rehabilitation, hearing loss can cause detrimental effects on speech, language, developmental, educational, and cognitive outcomes in children.

OBSERVATIONS

Consequences of hearing loss in children include worse outcomes in speech, language, education, social functioning, cognitive abilities, and quality of life. Hearing loss can be congenital, delayed onset, or acquired with possible etiologies including congenital infections, genetic causes including syndromic and nonsyndromic etiologies, and trauma, among others. Evaluation of hearing loss must be based on suspected diagnosis, type, laterality and degree of hearing loss, age of onset, and additional variables such as exposure to cranial irradiation. Hearing rehabilitation for children with hearing loss may include use of hearing aids, cochlear implants, bone anchored devices, or use of assistive devices such as frequency modulating systems.

CONCLUSIONS AND RELEVANCE

Hearing loss in children is common, and there has been substantial progress in diagnosis and management of these cases. Early identification of hearing loss and understanding its etiology can assist with prognosis and counseling of families. In addition, awareness of treatment strategies including the many hearing device options, cochlear implant, and assistive devices can help direct management of the patient to optimize outcomes.

Speech intelligibility and auditory perception of pre-school children with Hearing Aid, cochlear implant and Typical Hearing

Purpose

There is a growing interest in speech intelligibility and auditory perception of deaf children. The aim of the present study was to compare speech intelligibility and auditory perception of pre-school children with Hearing Aid (HA), Cochlear Implant (CI), and Typical Hearing (TH).

Methods

The research design was descriptive-analytic and comparative. The participants comprised 75 male pre-school children aged 4–6 years in the 2017–2018 from Tehran, Iran. The participants were divided into three groups, and each group consisted of 25 children. The first and second groups were respectively selected from pre-school children with HA and CI using the convenience sampling method, while the third group was selected from pre-school children with TH by random sampling method. All children completed Speech Intelligibility Rating and Categories of Auditory Performance Questionnaires.

Results

The findings indicated that the mean scores of speech intelligibility and auditory perception of the group with TH were significantly higher than those of the other groups (P < 0.0001). The mean scores of speech intelligibility in the group with CI did not significantly differ from those of the group with HA (P < 0.38). Also, the mean scores of auditory perception in the group with CI were significantly higher than those of the group with HA (P < 0.002).

Conclusion

The results showed that auditory perception in children with CI was significantly higher than children with HA. This finding highlights the importance of cochlear implantation at a younger age and its significant impact on auditory perception in deaf children.

Long-term treatment outcomes in children with auditory neuropathy spectrum disorder (ANSD)

INTRODUCTION

The present article shows long-term results in the hearing and speech development of children with auditory neuropathy spectrum disorder (ANSD). Some children were followed up for nearly 20 years, monitoring their progress through childhood into adulthood.

METHODS

This retrospective study examined data from 10 children who were diagnosed and treated at our tertiary referral center. All children were provided with hearing aids and/or cochlear implants. The children's hearing and speech development and their social and educational development were evaluated.

RESULTS

Seven children were provided with cochlear implants on both sides; three children, one of which had single-sided deafness, received hearing aids. All children with cochlear implants on both sides used their devices full-time. Speech perception ranged between 100% and 0% on one side. Five children attended a school for the hearing impaired; four children attended a regular school. Four children attended vocational training.

CONCLUSIONS

At present, there is a lack of literature on the long-term outcomes of treatment in children with ANSD. The data presented show that the hearing and speech development in children with ANSD are significantly heterogeneous. Regular school education and social integration of children with ANSD can be achieved with intensive and supportive rehabilitative methods.

Comparison of ABR and ASSR using NB-chirp-stimuli in children with severe and profound hearing loss

INTRODUCTION

Objective techniques for hearing threshold estimation in infants and children with profound or severe hearing loss play a key role in pediatric audiology to prevent speech acquisition disorders by choosing the adequate therapy. Auditory brainstem responses and auditory steady-state responses are available for frequency-dependent hearing threshold estimations and both techniques show strong correlations. However, various systems and stimuli are available, which is one reason why comparison is challenging, and, so far, no single "gold standard" could be established for hearing threshold estimation in children suffering from profound or severe hearing loss. The aim of the study was to compare hearing threshold estimations in children with profound or severe hearing loss derived with narrow-band CE-chirps evoked auditory brainstem responses and auditory steady-state response.

SUBJECTS

and Methods: 71 children (121 ears) with an age from 3 month to 15 years were measured with the Interacoustics Eclipse EP25 ABR system® (Denmark) with narrow-band CE-chirps® at 500, 1000, 2000 and 4000 Hz under identical conditions.

RESULTS

Auditory brainstem responses and auditory steady-state responses highly correlate (r = 0.694, p < 0.001). Correlation coefficients differ depending on the center frequency and patient age. Generally, auditory steady-state responses show a better hearing threshold than auditory brainstem responses or a remaining hearing threshold when auditory brainstem responses could not be obtained. In approximately 15% of cases this would have affected the therapeutic strategy when only taking one technique into account.

CONCLUSION

Auditory brainstem responses and auditory steady-state responses should be jointly used in the diagnostic approach in children with suspected profound or severe hearing loss.

Evaluation and therapy outcome in children with auditory neuropathy spectrum disorder (ANSD)

OBJECTIVES

The aims of the present study are to: describe diagnostic findings in patients with auditory neuropathy spectrum disorder (ANSD); and demonstrate the outcomes of different therapies like hearing aids (HAs) or cochlear implantation.

METHODS

32 children were diagnosed and treated at our tertiary referral center and provided with HAs or cochlear implants (CIs). All of them underwent free-field or pure-tone audiometry. Additionally, otoacoustic emissions (OAEs), impedance measurements, auditory brainstem responses (ABRs), auditory steady-state responses (ASSR), electrocochleography, and cranial magnetic resonance imaging (cMRI) were all performed. Some patients also underwent genetic evaluation. Following suitable provision pediatric audiological tests, psychological developmental diagnostic and speech and language assessments were carried out at regular intervals in all the children.

RESULTS

OAEs could initially be recorded in most of the children; 17 had no ABRs. The other eight children had a poor ABR morphology. Most of the children had typical, long-oscillating cochlear microphonics (CMs) in their ABRs, which was also observed in all of those who underwent electrocochleography. Eight children were provided with a HA and 17 received a CI. The functional gain was between 32 and 65 decibel (dB) with HAs and between 32 and 50 dB with CI. A speech discrimination level between 35 and 100% was achieved during open-set monosyllabic word tests in quiet with HA or CI. With the Hochmair-Schulz-Moser (HSM) sentence test at 65 dB SPL (sound pressure level), 75% of the children with a CI achieved a speech discrimination in noise score of at least 60% at a signal to noise ratio (SNR) of 5, and four scored 80% or higher. Most of the children (72%) were full-time users of their devices. All the children with a CI used it on a regular basis.

CONCLUSION

Only a few case reports are available in the literature regarding the long-term outcomes of ANSD therapy. The present study reveals satisfactory outcomes with respect to hearing and speech discrimination in children with CIs or HAs. The nearly permanent use of the devices reflects a subjective benefit for the children. Provision with a suitable hearing device depends on audiological results, the speech and language development of an individual child, and any accompanying disorders. Repeated audiological evaluations, interdisciplinary diagnostics, and intensive hearing and speech therapy are essential for adequate rehabilitation of this group of children.

Effects of Early Acoustic Hearing on Speech Perception and Language for Pediatric Cochlear Implant Recipients

Purpose The overall goal of the current study was to identify an optimal level and duration of acoustic experience that facilitates language development for pediatric cochlear implant (CI) recipients-specifically, to determine whether there is an optimal duration of hearing aid (HA) use and unaided threshold levels that should be considered before proceeding to bilateral CIs. Method A total of 117 pediatric CI recipients (ages 5-9 years) were given speech perception and standardized tests of receptive vocabulary and language. The speech perception battery included tests of segmental perception (e.g., word recognition in quiet and noise, and vowels and consonants in quiet) and of suprasegmental perception (e.g., talker and stress discrimination, and emotion identification). Hierarchical regression analyses were used to determine the effects of speech perception on language scores, and the effects of residual hearing level (unaided pure-tone average [PTA]) and duration of HA use on speech perception. Results A continuum of residual hearing levels and the length of HA use were represented by calculating the unaided PTA of the ear with the longest duration of HA use for each child. All children wore 2 devices: Some wore bimodal devices, while others received their 2nd CI either simultaneously or sequentially, representing a wide range of HA use (0.03-9.05 years). Regression analyses indicate that suprasegmental perception contributes unique variance to receptive language scores and that both segmental and suprasegmental skills each contribute independently to receptive vocabulary scores. Also, analyses revealed an optimal duration of HA use for each of 3 ranges of hearing loss severity (with mean PTAs of 73, 92, and 111 dB HL) that maximizes suprasegmental perception. Conclusions For children with the most profound losses, early bilateral CIs provide the greatest opportunity for developing good spoken language skills. For those with moderate-to-severe losses, however, a prescribed period of bimodal use may be more advantageous for developing good spoken language skills.

The Role of Multiple Articulatory Channels of Sign-Supported Speech Revealed by Visual Processing

Purpose The use of sign-supported speech (SSS) in the education of deaf students has been recently discussed in relation to its usefulness with deaf children using cochlear implants. To clarify the benefits of SSS for comprehension, 2 eye-tracking experiments aimed to detect the extent to which signs are actively processed in this mode of communication. Method Participants were 36 deaf adolescents, including cochlear implant users and native deaf signers. Experiment 1 attempted to shift observers' foveal attention to the linguistic source in SSS from which most information is extracted, lip movements or signs, by magnifying the face area, thus modifying lip movements perceptual accessibility (magnified condition), and by constraining the visual field to either the face or the sign through a moving window paradigm (gaze contingent condition). Experiment 2 aimed to explore the reliance on signs in SSS by occasionally producing a mismatch between sign and speech. Participants were required to concentrate upon the orally transmitted message. Results In Experiment 1, analyses revealed a greater number of fixations toward the signs and a reduction in accuracy in the gaze contingent condition across all participants. Fixations toward signs were also increased in the magnified condition. In Experiment 2, results indicated less accuracy in the mismatching condition across all participants. Participants looked more at the sign when it was inconsistent with speech. Conclusions All participants, even those with residual hearing, rely on signs when attending SSS, either peripherally or through overt attention, depending on the perceptual conditions. Supplemental Material https://doi.org/10.23641/asha.8121191.

Assistive Hearing Technology for Deaf and Hard-of-Hearing Spoken Language Learners

Radical advancements in hearing technology in the last 30 years have offered some deaf and hard-of-hearing (DHH) children the adequate auditory access necessary to acquire spoken language with high-quality early intervention. However, meaningful achievement gaps in reading and spoken language persist despite the engineering marvel of modern hearing aids and cochlear implants. Moreover, there is enormous unexplained variability in spoken language and literacy outcomes. Aspects of signal processing in both hearing aids and cochlear implants are discussed as they relate to spoken language outcomes in preschool and school-age children. In suggesting areas for future research, a case is made for not only expanding the search for mechanisms of influence on outcomes outside of traditional device- and child-related factors, but also for framing the search within Biopsychosocial systems theories. This theoretical approach incorporates systems of risk factors across many levels, as well as the bidirectional and complex ways in which factors influence each other. The combination of sophisticated hearing technology and a fuller understanding of the complex environmental and biological factors that shape development will help maximize spoken language outcomes in DHH children and contribute to laying the groundwork for successful literacy and academic development.

The maxillary nerve block for in-office hybrid balloon sinus dilation procedures: A preliminary study

Transitioning of rhinologic procedures from the operating room to the office setting in selected patients is a rising trend. An effective pain-control, patient-preparation protocol is essential, especially with advanced in-office rhinologic procedures such as hybrid balloon sinus dilation (BSD), in which other procedures such as ethmoidectomy, turbinate reduction, and other procedures are concomitantly performed. A regimen using oral sedation, topical tetracaine gel, topical tetracaine/epinephrine-soaked cottonoid packs, and intranasal local infiltrative anesthesia can vary significantly in effectiveness and be suboptimal at times (as determined by using treated patients as historical controls). A modification of this regimen was subsequently used, incorporating the maxillary nerve block, and qualitative differences were then assessed retrospectively between the two regimens. Twenty-five consecutive patients were retrospectively studied who underwent hybrid BSD procedures in the office setting using the maxillary nerve-block regimen modification. All patients underwent BSD of the sphenoid, frontal, and maxillary sinuses with anterior and partial posterior ethmoidectomies. Five patients also underwent septoplasty, and 18 patients underwent inferior turbinate reduction procedures. Twenty-four patients received oral sedation, and all patients received topical tetracaine/epinephrine-soaked cottonoid packs. The topical tetracaine gel was dropped after 5 patients because it was not felt to be needed anymore. No intranasal local infiltrative anesthesia was used. Several qualitative differences were observed after modifying the patient-preparation regimen incorporating the maxillary nerve block. The most important observation seen with this modification was a consistently reproducible, dense anesthesia coverage over the entire nasal cavity with good paranasal sinus coverage. This modification eliminated intranasal bleeding and swelling associated with intranasal local anesthetic injections. No complications were encountered. This preliminary study provides support for use and further evaluation of the maxillary nerve block for in-office rhinologic procedures. If the trend continues to rise in performing advanced in-office rhinologic procedures in selected patients, the maxillary nerve block may find a place in the patient-preparation protocol.

Sound Localization and Speech Perception in Noise of Pediatric Cochlear Implant Recipients: Bimodal Fitting Versus Bilateral Cochlear Implants

OBJECTIVES

The aim of this study was to compare binaural performance of auditory localization task and speech perception in babble measure between children who use a cochlear implant (CI) in one ear and a hearing aid (HA) in the other (bimodal fitting) and those who use bilateral CIs.

DESIGN

Thirteen children (mean age ± SD = 10 ± 2.9 years) with bilateral CIs and 19 children with bimodal fitting were recruited to participate. Sound localization was assessed using a 13-loudspeaker array in a quiet sound-treated booth. Speakers were placed in an arc from -90° azimuth to +90° azimuth (15° interval) in horizontal plane. To assess the accuracy of sound location identification, we calculated the absolute error in degrees between the target speaker and the response speaker during each trial. The mean absolute error was computed by dividing the sum of absolute errors by the total number of trials. We also calculated the hemifield identification score to reflect the accuracy of right/left discrimination. Speech-in-babble perception was also measured in the sound field using target speech presented from the front speaker. Eight-talker babble was presented in the following four different listening conditions: from the front speaker (0°), from one of the two side speakers (+90° or -90°), from both side speakers (±90°). Speech, spatial, and quality questionnaire was administered.

RESULTS

When the two groups of children were directly compared with each other, there was no significant difference in localization accuracy ability or hemifield identification score under binaural condition. Performance in speech perception test was also similar to each other under most babble conditions. However, when the babble was from the first device side (CI side for children with bimodal stimulation or first CI side for children with bilateral CIs), speech understanding in babble by bilateral CI users was significantly better than that by bimodal listeners. Speech, spatial, and quality scores were comparable with each other between the two groups.

CONCLUSIONS

Overall, the binaural performance was similar to each other between children who are fit with two CIs (CI + CI) and those who use bimodal stimulation (HA + CI) in most conditions. However, the bilateral CI group showed better speech perception than the bimodal CI group when babble was from the first device side (first CI side for bilateral CI users or CI side for bimodal listeners). Therefore, if bimodal performance is significantly below the mean bilateral CI performance on speech perception in babble, these results suggest that a child should be considered to transit from bimodal stimulation to bilateral CIs.

Learning from the Longitudinal Outcomes of Children with Hearing Impairment (LOCHI) study: summary of 5-year findings and implications

OBJECTIVE

This article summarises findings of the Longitudinal Outcomes of Children with Hearing Impairment (LOCHI) study, and discusses implications of the findings for research and clinical practice.

DESIGN

A population-based study on outcomes of children with hearing loss. Evaluations were conducted at five years of age.

STUDY SAMPLE

Participants were 470 children born with hearing loss between 2002 and 2007 in New South Wales, Victoria and Queensland in Australia, and who first received amplification or cochlear implantation by three years of age.

RESULTS

The earlier hearing aids or cochlear implants were fitted, the better the speech, language and functional performance outcomes. Better speech perception was also associated with better language and higher cognitive abilities. Better psychosocial development was associated with better language and functional performance. Higher maternal education level was also associated with better outcomes. Qualitative analyses of parental perspectives revealed the multiple facets of their involvement in intervention.

CONCLUSIONS

The LOCHI study has shown that early fitting of hearing devices is key to achieving better speech, language and functional performance outcomes for children with hearing loss. The findings are discussed in relation to changes in clinical practice and directions for future research.

Effects of residual hearing on cochlear implant outcomes in children: A systematic-review

OBJECTIVES

to investigate if preoperative residual hearing in prelingually deafened children can interfere on cochlear implant indication and outcomes.

METHODS

a systematic-review was conducted in five international databases up to November-2016, to locate articles that evaluated cochlear implantation in children with some degree of preoperative residual hearing. Outcomes were auditory, language and cognition performances after cochlear implant. The quality of the studies was assessed and classified according to the Oxford Levels of Evidence table - 2011. Risk of biases were also described.

RESULTS

From the 30 articles reviewed, two types of questions were identified: (a) what are the benefits of cochlear implantation in children with residual hearing? (b) is the preoperative residual hearing a predictor of cochlear implant outcome? Studies ranged from 04 to 188 subjects, evaluating populations between 1.8 and 10.3 years old. The definition of residual hearing varied between studies. The majority of articles (n = 22) evaluated speech perception as the outcome and 14 also assessed language and speech production.

CONCLUSION

There is evidence that cochlear implant is beneficial to children with residual hearing. Preoperative residual hearing seems to be valuable to predict speech perception outcomes after cochlear implantation, even though the mechanism of how it happens is not clear. More extensive researches must be conducted in order to make recommendations and to set prognosis for cochlear implants based on children preoperative residual hearing.

Barriers to early cochlear implantation

OBJECTIVE

Identify variables associated with paediatric access to cochlear implants (CIs).

DESIGN

Part 1. Trends over time for age at CI surgery (N = 802) and age at hearing aid (HA) fitting (n = 487) were examined with regard to periods before, during, and after newborn hearing screening (NHS). Part 2. Demographic factors were explored for 417 children implanted under 3 years of age. Part 3. Pre-implant steps for the first 20 children to receive CIs under 12 months were examined.

RESULTS

Part 1. Age at HA fitting and CI surgery reduced over time, and were associated with NHS implementation. Part 2. For children implanted under 3 years, earlier age at HA fitting and higher family socio-economic status were associated with earlier CI. Progressive hearing loss was associated with later CIs. Children with a Connexin 26 diagnosis received CIs earlier than children with a premature / low birth weight history. Part 3. The longest pre-CI steps were Step 1: Birth to diagnosis/identification of hearing loss (mean 16.43 weeks), and Step 11: MRI scans to implant surgery (mean 15.05 weeks) for the first 20 infants with CIs under 12 months.

CONCLUSION

NHS implementation was associated with reductions in age at device intervention in this cohort.

Pathophysiological mechanisms and functional hearing consequences of auditory neuropathy

The effects of inner ear abnormality on audibility have been explored since the early 20th century when sound detection measures were first used to define and quantify 'hearing loss'. The development in the 1970s of objective measures of cochlear hair cell function (cochlear microphonics, otoacoustic emissions, summating potentials) and auditory nerve/brainstem activity (auditory brainstem responses) have made it possible to distinguish both synaptic and auditory nerve disorders from sensory receptor loss. This distinction is critically important when considering aetiology and management. In this review we address the clinical and pathophysiological features of auditory neuropathy that distinguish site(s) of dysfunction. We describe the diagnostic criteria for: (i) presynaptic disorders affecting inner hair cells and ribbon synapses; (ii) postsynaptic disorders affecting unmyelinated auditory nerve dendrites; (iii) postsynaptic disorders affecting auditory ganglion cells and their myelinated axons and dendrites; and (iv) central neural pathway disorders affecting the auditory brainstem. We review data and principles to identify treatment options for affected patients and explore their benefits as a function of site of lesion.

Pediatric Cochlear Implantation in Residual Hearing Candidates

Objectives:

To propose categories for the various types of residual hearing in children and to review the outcomes of cochlear implantation (CI) in children with these different hearing conditions.

Methods:

We identified 53 children with residual hearing who had received a cochlear implant. Five groups were arbitrarily defined based on auditory features: G1, characterized by low-frequency residual hearing (n = 5); G2, characterized by severe sensorineural hearing loss (SNHL) and low speech discrimination (n = 12); G3, characterized by asymmetric SNHL (n = 9); G4, characterized by progressive SNHL (n = 15); and G5, characterized by fluctuating SNHL (n = 12). The main audiometric features and outcomes of the groups were analyzed.

Results:

The mean age at implantation was 10.15 years (range, 2.5-21 years). The mean preoperative score for the discrimination of open-set words was 48%; this score increased to 74% at 12 months and 81% at 24 months after the CI procedure (G1 to G5, respectively: 79/62/77%, 50/81/88%, 59/75/86%, 35/74/67%, and 39/69/80%). Children who were implanted after 10 years of age did not improve as much as those who were implanted at a younger age (open-set word list speech perception [OSW] score at 12 months: 62% vs 83%; P = .0009). Shorter delays before surgery were predictive of better performance ( P = .003). Inner ear malformation and SLC26A4 mutations were not predictive of the outcome.

Conclusions:

CIs provide better results compared with hearing aids in children with residual hearing. Factors that may impact the benefits of CIs in patients with residual hearing are age, delay in performing the CI procedure, which ear is implanted, and initial underestimation of the patient’s hearing difficulties.

Foundations for literacy: An early literacy intervention for deaf and hard-of-hearing children

The present study evaluated the efficacy of a new preschool early literacy intervention created specifically for deaf and hard-of-hearing (DHH) children with functional hearing. Teachers implemented Foundations for Literacy with 25 DHH children in 2 schools (intervention group). One school used only spoken language, and the other used sign with and without spoken language. A "business as usual" comparison group included 33 DHH children who were matched on key characteristics with the intervention children but attended schools that did not implement Foundations for Literacy. Children's hearing losses ranged from moderate to profound. Approximately half of the children had cochlear implants. All children had sufficient speech perception skills to identify referents of spoken words from closed sets of items. Teachers taught small groups of intervention children an hour a day, 4 days a week for the school year. From fall to spring, intervention children made significantly greater gains on tests of phonological awareness, letter-sound knowledge, and expressive vocabulary than did comparison children. In addition, intervention children showed significant increases in standard scores (based on hearing norms) on phonological awareness and vocabulary tests. This quasi-experimental study suggests that the intervention shows promise for improving early literacy skills of DHH children with functional hearing.

Development of a safe dexamethasone-eluting electrode array for cochlear implantation

OBJECTIVES

Cochlear implantation can result in trauma leading to increased tissue response and loss of residual hearing. A single intratympanic application of the corticosteroid dexamethasone is sometimes used clinically during surgery to combat the potential effect of trauma on residual hearing. This project looked at the safety and efficacy of dexamethasone eluted from an intracochlear array in vivo.

METHODS

Three trials were conducted using normal hearing adult guinea pigs implanted with successive iterations of dexamethasone-eluting (DX1, DX2, and DX3) or non-eluting (control) intracochlear electrode arrays. The experimental period for each animal was 90 days during which hearing tests were performed at multiple time points.

RESULTS

There was no significant difference between matched control array and dexamethasone array groups in terms of spiral ganglion neuron density, organ of Corti condition, or fibrosis and ossification. A cochleostomy seal was present in all implanted cochleae. There were no differences in the degree of hearing threshold shifts between DX1 and DX3 and their respective control arrays. Cochleae implanted with DX2 arrays showed less hearing loss and marginally better spiral ganglion neuron survival than their control array counterparts. Post-explant inspection of the DX2 and DX3 arrays revealed a difference in pore density following dexamethasone elution.

CONCLUSION

The dexamethasone doses used were safe in the guinea pig cochlea. Dexamethasone did not inhibit formation of a cochleostomy seal. The level of hearing protection afforded by dexamethasone eluting from an intracochlear array may depend upon the degree of elution and level of trauma inflicted.

Pediatric cochlear implantation: expanding applications and outcomes

Cochlear implantation is a revolutionary yet time-sensitive treatment for deaf children that must be performed within a critical window of time, in early life, for a congenitally deafened child to receive maximum benefit. Potential candidates should therefore be referred for evaluation early. Primary reasons for delay of cochlear implantation include slow referrals for care, parental delays, and payer delays. It is vital that all newborn children undergo hearing screening to identify deaf children at birth, and for parents, health care providers, and health care payers to be educated about the indications, important benefits, and reasonable risks of cochlear implantation for deaf children.

Spoken language benefits of extending cochlear implant candidacy below 12 months of age

OBJECTIVE

To test the hypothesis that cochlear implantation surgery before 12 months of age yields better spoken language results than surgery between 12 and 18 months of age.

STUDY DESIGN

Language testing administered to children at 4.5 years of age (± 2 mo).

SETTING

Schools, speech-language therapy offices, and cochlear implant (CI) centers in the United States and Canada.

PARTICIPANTS

Sixty-nine children who received a cochlear implant between ages 6 and 18 months of age. All children were learning to communicate via listening and spoken language in English-speaking families.

MAIN OUTCOME MEASURE

Standard scores on receptive vocabulary, expressive, and receptive language (includes grammar).

RESULTS

Children with CI surgery at 6 to 11 months (n = 27) achieved higher scores on all measures as compared with those with surgery at 12 to 18 months (n = 42). Regression analysis revealed a linear relationship between age of implantation and language outcomes throughout the 6- to 18-month surgery-age range.

CONCLUSION

For children in intervention programs emphasizing listening and spoken language, cochlear implantation before 12 months of age seems to provide a significant advantage for spoken language achievement observed at 4.5 years of age.

Multicenter evaluation of Neurelec Digisonic® SP cochlear implant reliability

Over the past decade, the adoption of universal hearing screening in newborns has led to earlier detection of hearing problems and significant lowering of the age of first cochlear implantation. As a consequence, recipients are now expected to keep their cochlear implants (CIs) for a longer period of time. Comprehensive longitudinal information on CI reliability is essential for device choice. The aim of this study was to assess the reliability (in children and adults) of the latest generation of the Digisonic(®) SP CI launched in 2006 by Neurelec. Failure rate (FR) and cumulative survival rate (CSR) for a 5-year period were calculated. This survey is a multicenter retrospective study. A questionnaire was sent to nine CI centers requesting information about patients implanted with Neurelec Digisonic(®) SP CIs. FR and CSR over a 5-year period were calculated on this group. Collaborating centers collected data on 672 patients (362 children and 310 adults) implanted between March 2006 and March 2011. The overall rate of explantation was 2.23 % (15 cases): six devices were explanted due to device failure (0.89 %) and nine were explanted for medical reasons (1.34 %). Four patients were lost to follow-up. The CSR at 5 years was 98.51 % on all patients, 98.48 % for children and 98.57 % for adults. FR was 0.97 % for adults and 0.83 % for children. This first independent study that assesses FR and CSR on the current generation of Digisonic(®) SP CI represents an important resource that can help clinicians and patients during their device choice.

Cochlear implants in children younger than 6 months

OBJECTIVES

(1) To determine the long-term outcomes of cochlear implantation in children implanted younger than 6 months and (2) to evaluate auditory-based performance in very young children compared with older children, all with profound sensorineural bilateral hearing loss.

STUDY DESIGN

Prospective cohort study.

SETTING

Tertiary referral center.

SUBJECTS AND METHODS

Twelve subjects aged 2 to 6 months, 9 aged 7 to 12 months, 11 aged 13 to 18 months, and 13 aged 19 to 24 months, all with profound bilateral hearing loss, were fitted with cochlear implants and followed longitudinally for 4 years. Subjects were developmentally normal with no additional disabilities (visual, motor, or cognitive). Auditory-based communication outcomes included tests for speech perception, receptive language development, receptive vocabulary, and speech production.

RESULTS

Age at cochlear implantation was a significant factor in most outcome measures, contributing significantly to speech perception, speech production, and language outcomes. There were no major complications and no significantly higher rates of minor complications in the younger children.

CONCLUSION

This article reports an uncontrolled observational study on a small group of infants fitted with cochlear implants following personal audiological criteria and, up to now, with limited literature support due to the innovative nature of the study. This study shows, for the first time, significantly improved auditory-based outcomes in children implanted younger than 6 months and without an increased rate of complications. The data from the present study must be considered as explorative, and a more extensive study is required.