Advantages of Cochlear Implantation in Prelingual Deaf Children before 2 Years of Age when Compared with Later Implantation

Enduring advantages of early cochlear implantation for spoken language development

PURPOSE

In this article, the authors sought to determine whether the precise age of implantation (AOI) remains an important predictor of spoken language outcomes in later childhood for those who received a cochlear implant (CI) between 12 and 38 months of age. Relative advantages of receiving a bilateral CI after age 4.5 years, better pre-CI-aided hearing, and longer CI experience were also examined.

METHOD

Sixty children participated in a prospective longitudinal study of outcomes at 4.5 and 10.5 years of age. Twenty-nine children received a sequential second CI. Test scores were compared with normative samples of hearing age mates, and predictors of outcomes were identified.

RESULTS

Standard scores on language tests at 10.5 years of age remained significantly correlated with age of first cochlear implantation. Scores were not associated with receipt of a second, sequentially acquired CI. Significantly higher scores were achieved for vocabulary as compared with overall language, a finding not evident when the children were tested at younger ages.

CONCLUSION

Age-appropriate spoken language skills continued to be more likely with younger AOI, even after an average of 8.6 years of additional CI use. Receipt of a second implant between ages 4 and 10 years and longer duration of device use did not provide significant added benefit.

Performance of Indian Children with Cochlear Implant on PEACH Scale

This study compares the functional language performance of Tamil-speaking children (n = 30) who received a cochlear implant (CI) before 2 years of age (earlier implanted group: EIG) and between 3 and 4 years of age (later implanted group: LIG). Everyday functional language of children was evaluated by interviewing parents using the adapted Parents' Evaluation of Aural/Oral Performance of Children (PEACH) Questionnaire in Tamil language. On average, both groups of children had difficulties in everyday language functioning. However, functional results of EIG were better than those of LIG. In addition significant correlations were found between age at intervention and PEACH score. The evidence lends support to early intervention increasing the functional performance of the children fitted with CI. PEACH can be a clinically feasible evaluation tool to implement in practice for clinicians to obtain meaningful information regarding children's auditory performance in real life at childhood.

Phonetic processing during the acquisition of new words in 3-to-6-year-old French-speaking deaf children with cochlear implants

The present study explores phonetic processing in deaf children with cochlear implants (CIs) when they have to learn phonetically similar words. Forty-six 34-to-78-month-old French-speaking deaf children with CIs were tested on 16 different trials. In each trial, they were first trained with two word-object pairings, and then a third object was presented and labeled with one of the familiar words. Children were asked to match one of the previously labeled objects with the third (same-labeled) object. Each pair of words contrasted on either the initial consonant or the first vowel by one or several phonetic features. The results show that deaf children with CIs are able to establish a new referential link between a word and an object. However, their performance is lower than that previously observed in normal-hearing children (NH). In such a situation, they process contrasts involving several phonetic features correctly, but show difficulties with minimal contrasts. The ability to recruit fine phonetic sensitivity during word learning appears to be influenced mainly by duration of implant use, with an overall increase of performance during the 3 years after implantation. There was no chronological age effect, nor age at implantation effect on the quality of processing. Difficulty with minimal contrasts and the absence of any age at implantation effects in this age range are discussed in light of recent studies on lexical development.

LEARNING OUTCOMES

After reading this article, the reader will be able to recognize the perceptual skills of children with cochlear implants and distinguish those perceptual features that are difficult for the children to perceive.

A case study assessing the auditory and speech development of four children implanted with cochlear implants by the chronological age of 12 months

Children with severe hearing loss most likely receive the greatest benefit from a cochlear implant (CI) when implanted at less than 2 years of age. Children with a hearing loss may also benefit greater from binaural sensory stimulation. Four children who received their first CI under 12 months of age were included in this study. Effects on auditory development were determined using the German LittlEARS Auditory Questionnaire, closed- and open-set monosyllabic word tests, aided free-field, the Mainzer and Göttinger speech discrimination tests, Monosyllabic-Trochee-Polysyllabic (MTP), and Listening Progress Profile (LiP). Speech production and grammar development were evaluated using a German language speech development test (SETK), reception of grammar test (TROG-D) and active vocabulary test (AWST-R). The data showed that children implanted under 12 months of age reached open-set monosyllabic word discrimination at an age of 24 months. LiP results improved over time, and children recognized 100% of words in the MTP test after 12 months. All children performed as well as or better than their hearing peers in speech production and grammar development. SETK showed that the speech development of these children was in general age appropriate. The data suggests that early hearing loss intervention benefits speech and language development and supports the trend towards early cochlear implantation. Furthermore, the data emphasizes the potential benefits associated with bilateral implantation.

Auditory and oral language abilities in children with cochlear implants: a case study

The cochlear implant (CI) represents the most important advance in the treatment of individuals with severe to profound bilateral hearing loss who do not benefit from hearing aids. Children who receive the CI during the critical period of neuroplasticity of the auditory system, when combined with speech therapy, have the chance to develop the auditory and linguistic skills similarly to their normal hearing peers. Two cases of implanted children are presented in this study, and one of them was not enrolled in a formal aurioral therapeutic program since the implantation surgery. At the moment of language and auditory assessment, the children were 2 years and 5 months old, and the CI had been used for 11 months. According to the results presented, it was observed that the child enrolled in rehabilitation program had better auditory and language performance when compared to the other child. Despite the remarkable benefits that the CI provides to children with hearing impairment, the device itself only provides the child with the audibility of environmental sounds and speech signal. For the auditory and language development to happen, it is necessary, among other factors, a speech-language intervention, with partnership between professionals and parents.

Listen up: children with early identified hearing loss achieve age-appropriate speech/language outcomes by 3 years-of-age

OBJECTIVES

Age-appropriate speech/language outcomes for children with early identified hearing loss are a possibility but not a certainty. Identification of children most likely to achieve optimal outcomes is complicated by the heterogeneity of the children involved in outcome research, who present with a range of malleable (e.g. age of identification and cochlear implantation, type of intervention, communication mode) and non-malleable (e.g. degree of hearing loss) factors. This study considered whether a homogenous cohort of early identified children (≤ 12 months), with all severities of hearing loss and no other concomitant diagnoses could not only significantly outperform a similarly homogenous cohort of children who were later identified (>12 months to <5 years), but also achieve and maintain age-appropriate speech/language outcomes by 3, 4 and 5 years of age.

METHODS

A mixed prospective/retrospective comparative study of a homogenous cohort of 45 early identified (≤ 12 months) and 49 late identified (> 12 months to < 5 years) children with hearing loss was conducted. The children all attended the same oral auditory-verbal early intervention programme. Speech/language assessments standardized on typically developing hearing children were conducted at 3, 4 and 5 years of age.

RESULTS

The early identified children significantly outperformed the late identified at all ages and for all severities of HL. By 3 years of age, 93% of all early identified participants scored within normal limits (WNL) for speech; 90% were WNL for understanding vocabulary; and 95% were WNL for receptive and expressive language. Progress was maintained and improved so that by 5 years of age, 96% were WNL for speech, with 100% WNL for language.

CONCLUSIONS

This study found that most children with all severities of hearing loss and no other concomitant diagnosed condition, who were early diagnosed; received amplification by 3 months; enrolled into AV intervention by 6 months and received a cochlear implant by 18 months if required, were able to "keep up with" rather than "catch up to" their typically hearing peers by 3 years of age on measures of speech and language, including children with profound hearing loss. By 5 years, all children achieved typical language development and 96% typical speech.

Children using cochlear implants capitalize on acoustical hearing for music perception

Cochlear implants (CIs) electrically stimulate the auditory nerve providing children who are deaf with access to speech and music. Because of device limitations, it was hypothesized that children using CIs develop abnormal perception of musical cues. Perception of pitch and rhythm as well as memory for music was measured by the children’s version of the Montreal Battery of Evaluation of Amusia (MBEA) in 23 unilateral CI users and 22 age-matched children with normal hearing. Children with CIs were less accurate than their normal hearing peers (p < 0.05). CI users were best able to discern rhythm changes (p < 0.01) and to remember musical pieces (p < 0.01). Contrary to expectations, abilities to hear cues in music improved as the age at implantation increased (p < 0.01). Because the children implanted at older ages also had better low frequency hearing prior to cochlear implantation and were able to use this hearing by wearing hearing aids. Access to early acoustical hearing in the lower frequency ranges appears to establish a base for music perception, which can be accessed with later electrical CI hearing.

Two portuguese cochlear implanted dizygotic twins: a case report

Individual's hearing performance after cochlear implant (CI) is variable and depends on different factors such as etiology of deafness, age at implantation, and social/family hearing environment. Here we report the case of dizygotic twins, boy and girl, presenting with neurosensorial profound deafness prior CI (age of implantation = 3.5 years old). Both parents have severe/profound deafness, since childhood, and use sign language as primary mode of communication. Clinical and genetic characterization was performed, as well as the assessment of the auditory and oral (re)habilitation after CI, applying a battery of audiological, speech, and language tests. The twin girl and the father were homozygous for the c.35delG mutation in the GJB2 gene, while the twin boy and the mother were compound heterozygotes, both monoallelic for c.35delG and for the deletion del(GJB6-D13S1830) in the GJB6 gene. The remaining hearing impaired relatives were c.35delG homozygotes. The genetic cause of deafness was thus identified in this family. Some noteworthy differences were observed regarding twins' auditory and oral performance after CI. Subsequent follow-up of these children allowed us to conclude that those differences were most likely due to the different environment in which the twins have been living than to their different GJB2/GJB6 genotypes.

Cochlear implants: clinical and societal outcomes

Over the past 30 years, hearing care clinicians have increasingly relied on cochlear implants to restore auditory sensitivity in selected patients with advanced sensorineural hearing loss. This article examines the impact of intervention with cochlear implantation in children and adults. The authors report a range of clinic-based results and patient-based outcomes reflected in the reported literature on cochlear implants. The authors describe the basic assessment of the physiologic response to auditory nerve stimulation; measures of receptive and productive benefit; and surveys of life effects as reflected measures of quality of life, educational attainment, and economic impact.

Cochlear blood flow and speech perception ability in cochlear implant users

OBJECTIVE

The effect of cochlear blood flow (CBF) on speech perception ability in cochlear implant (CI) users has not been reported. We investigated various factors influencing speech perception including CBF in CI users.

PATIENTS

Eighty-two patients who received CI surgery at an academic hospital.

METHODS

CBF was measured during CI surgery using laser Doppler flowmetry. The speech perception level was measured after a sufficient interval after CI surgery. Multivariate analysis was used to evaluate the influences of age, duration of deafness, sex, cause of deafness, and CBF on the speech perception level.

RESULTS

CBF decreased significantly with age but was not related to the speech perception level. In patients with congenital hearing loss, the speech perception level was significantly worse in children who received a CI at 3 years of age than in those who received a CI at 2 years of age or younger. Duration of deafness before CI surgery had deteriorative effects on the speech perception level.

CONCLUSION

CBF may be associated with progression of hearing loss. However, measuring CBF during CI surgery is not useful for predicting postoperative speech perception.

Cochlear implantation in children with postlingual hearing loss

OBJECTIVES/HYPOTHESIS

Although it is clear that early auditory stimulation through cochlear implantation (CI) has been shown to improve speech and language development trajectories for children with prelingual hearing loss, data supporting implantation in postlingual children are mostly lacking. The purpose of this study was to characterize speech perception abilities following CI in a group of children with previously well-developed language abilities.

STUDY DESIGN

Retrospective analysis.

METHODS

Twenty-eight hearing-impaired children who received CIs were selected for study based on the presence of well-developed spoken language skills before implantation. Fifteen children with prelingual hearing loss served as a control group. Speech perception skills were assessed using developmentally appropriate measures.

RESULTS

Children with postlingual hearing loss showed a statistically significant improvement in open-set speech perception scores as early as 6 months following CI, whereas prelingual children demonstrated significant improvements only after 24 months of use. Despite these early disparities in performance, the two groups were similar 36 months after implantation and beyond (60 months of implant use).

CONCLUSIONS

Children with well-developed language abilities before CI showed substantial (and statistically significant) early improvements in open-set speech perception abilities following implantation that continued beyond 2 years of follow-up. These results suggest that postlingual children are excellent candidates for CI.

Advances in auditory prostheses

PURPOSE OF REVIEW

Auditory prostheses use electric currents on multiple electrodes to stimulate auditory neurons and recreate auditory sensations in deaf people. Cochlear implants have restored hearing in more than 200  000 deaf adults and children to a level that allows most to understand speech. Here we review the reasons underlying these results and describe new directions in restoring hearing to additional patient populations and the design of new devices.

RECENT FINDINGS

From their early development about 50 years ago, cochlear implants have been well received and beneficial to people who had lost their hearing. Although those first implants did not allow high levels of speech understanding, they provided auditory information that worked synergistically with lip reading to improve communication. Present day cochlear implants provide excellent speech understanding in children and in postlingually deafened adults. Research is focused on improved signal processing and new electrode designs. Electric stimulation of the auditory brainstem can also produce excellent hearing in some children and adults.

SUMMARY

Auditory prostheses, both at the level of the sensory nerve and at the brainstem, can restore patterns of neural activation that are sufficient for high levels of speech understanding. These prostheses are not only clinically successful but also important tools for understanding sensory processing in the brain.

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.

Prevalence of mutations located at the dfnb1 locus in a population of cochlear implanted children in eastern Romania

OBJECTIVE

Hearing loss is one of the major public health problems, with a genetic etiology in more than 60% of cases. Connexin 26 and connexin 30 mutations are the most prevalent causes of deafness. The aim of this study is to characterize and to establish the prevalence of the GJB2 and GJB6 gene mutations in a population of cochlear implanted recipients from Eastern Romania, this being the first report of this type in our country.

METHODS

We present a retrospective study that enrolled 45 Caucasian cochlear implanted patients with non-syndromic sensorineural severe to profound, congenital or progressive with early-onset idiopathic hearing loss. We performed sequential analysis of exon 1 and the coding exon 2 of the GJB2 gene including also the splice sites and analysis of the deletions del(GJB6-D13S1830), del(GJB6-D13S1854) and del(chr13:19,837,343-19,968,698).

RESULTS

The genetic analysis of the GJB2 gene identified connexin 26 mutations in 22 patients out of 45 (12 homozygous for c.35delG, 6 compound heterozygous and 4 with mutations only on one allele). We found 6 different mutations, the most prevalent being c.35delG - found on 32 alleles, followed by p.W24* - found on 2 alleles. We did not identify the deletions del(GJB6-D13S1830), del(GJB6-D13S1854) and del(chr13:19,837,343-19,968,698).

CONCLUSIONS

Although the most prevalent mutation was c.35delG (80% from all types of mutations), unexpectedly we identified 5 more different mutations. The presence of 6 different mutations on the GJB2 gene has implications in hearing screening programs development in our region and in genetic counseling.

[Organisation of a cochlear implant programme]

A cochlear implant (CI) programme brings together a number of professionals who, during the stages of selection, surgery, programming, rehabilitation and monitoring, develop a series of tasks aimed at promoting comprehensive attention to the implanted patient. The aim of this paper was to describe in detail the tasks in each of the phases described in a programme of CI, materials and necessary equipment and the role of the professionals involved. It also raised a number of recommendations on how to develop a CI programme gradually to facilitate the progression from the simplest to the most complex cases.

Infants versus older children fitted with cochlear implants: performance over 10 years

OBJECTIVES

To investigate the efficacy of cochlear implants (CIs) in infants versus children operated at later age in term of spoken language skills and cognitive performances.

METHOD

The present prospective cohort study focuses on 19 children fitted with CIs between 2 and 11 months (X=6.4 months; SD=2.8 months). The results were compared with two groups of children implanted at 12-23 and 24-35 months. Auditory abilities were evaluated up to 10 years of CI use with: Category of Auditory Performance (CAP); Infant-Toddler Meaningful Auditory Integration Scale (IT-MAIS); Peabody Picture Vocabulary Test (PPVT-R); Test of Reception of Grammar (TROG) and Speech Intelligibility Rating (SIR). Cognitive evaluation was performed using selected subclasses from the Griffiths Mental Development Scale (GMDS, 0-8 years of age) and Leiter International Performance Scale-Revised (LIPS-R, 8-13 years of age).

RESULTS

The infant group showed significantly better results at the CAP than the older children from 12 months to 36 months after surgery (p<.05). Infants PPVT-R outcomes did not differ significantly from normal hearing children, whereas the older age groups never reached the values of normal hearing peers even after 10 years of CI use. TROG outcomes showed that infants developed significantly better grammar skills at 5 and 10 years of follow up (p<.001). Scores for the more complex subtests of the GMDS and LIPS-R were significantly higher in youngest age group (p<.05).

CONCLUSION

This study demonstrates improved auditory, speech language and cognitive performances in children implanted below 12 months of age compared to children implanted later.

Children with cochlear implants and developmental disabilities: a language skills study with developmentally matched hearing peers

The number of children receiving cochlear implants (CIs) with significant disabilities in addition to their deafness has increased substantially. Unfortunately, children with additional disabilities receiving CIs have largely been excluded from studies on cochlear implant outcomes. Thus limited data exists on outcomes in this population to guide pre-implant counseling for anticipated benefits. The study objectives were: (1) evaluate differences in post-cochlear implant language skills between children with cochlear implants and developmental disabilities and age/cognitively matched controls; (2) quantify possible discrepancies between language level and cognitive level. Fifteen children with a developmental disability who received a CI were matched 1:1 on nonverbal cognitive ability and age to hearing controls. Language was evaluated using Preschool Language Scale-IV and reported as language quotients. Multivariable mixed models for matched pairs analyzed differences in language levels between groups. No significant differences were seen between CI and control groups regarding insurance, maternal education, or family income level. Results of the multivariable models indicated that compared to matched controls, the CI group had significantly lower mean receptive (24.6 points, p=0.002) and mean expressive (21.9 points, p=0.001) language quotients after controlling for confounders such as number of therapies and weekly hours in therapy. Significant discrepancies between language level and cognitive level were seen among CI participants only. Compared to age- and cognitively matched controls, children with CIs had significantly lower language levels with delays disproportionate to their cognitive potential. Mechanisms behind this performance-functional gap need to be understood to deliver appropriate intervention strategies for this special population.

Cochlear implantation in patients with prelingual hearing loss

CONCLUSION

The average age at the time of cochlear implantation is progressively being reduced. While cochlear obstruction and perilymph/cerebello-spinal fluid gusher were found in some cases, preoperative MRI and CT scans were predictive of such occurrences. The preoperative developmental quotient in the Cognitive-Adaptive Area was strongly correlated to the postoperative development in the Language-Social Area.

OBJECTIVE

To summarize the background, implant devices, intraoperative findings, and postoperative developmental quotients of prelingually deafened patients who underwent cochlear implantation.

METHODS

We conducted a retrospective chart review of 134 prelingually deafened cochlear implant recipients.

RESULTS

The median age at implantation was 3 years and 5 months. Most patients were born deaf without any known etiologies. In most cases, the transmastoid facial recess approach was utilized. Cochlear obstruction was identified in four patients, all of whom lost their hearing as a result of meningitis. Perilymph/cerebello-spinal fluid gusher was observed in six patients with inner ear anomalies. The preoperative developmental quotient for the Cognitive-Adaptive Area showed significant correlation with the postoperative developmental quotient in the Language-Social Area with a correlation coefficient of 0.71.

DFNB1-associated deafness in Portuguese cochlear implant users: prevalence and impact on oral outcome

OBJECTIVES

Hearing loss is a condition that interferes with the development of the child at a cognitive and language level. Therefore, early diagnosis of deafness is important for (re)habilitation, namely through the use of cochlear implant (CI). The present study aimed at screening CI Portuguese individuals for the presence of mutations in the genes GJB2 and GJB6 (DFNB1 locus), and searching a possible correlation between the genotype and the oral habilitation outcome following implantation.

METHODS

Our sample included 117 CI individuals implanted longer than 5 years. Sequencing of GJB2 entire coding region was first performed. The presence of deletions del(GJB6-D13S1830) and del(GJB6-D13S1854) was subsequently tested by multiplex PCR. To assess the oral outcome of these individuals, a global score is calculated through a formula that integrates the results of a battery of speech and audiological tests routinely used in ORL services. This global oral performance score was used to test whether individuals with DFNB1-associated deafness perform significantly better than individuals without DFNB1-associated deafness.

RESULTS

In 35% of the cases, deafness was clearly associated to DFNB1. The most common mutated allele was c.35delG (85%). Other variants have also been found, namely p.Gly130Ala, p.Asn206Ser, p.Val37Ile, p.Glu47X, p.Arg184Trp, p.Trp24X and the two common GJB6 deletions, del(GJB6-D13S1854) and del(GJB6-D13S1830), the last one identified for the first time in our population. Regarding the oral outcome, after testing the homogeneity of the two groups it could be observed that, in mean, the individuals with DFNB1-associated deafness perform significantly better (p=0.012) than the individuals without DFNB1-associated deafness.

DISCUSSION AND CONCLUSION

This first screening of DFNB1 genes in the Portuguese CI population provides clear evidence of the high proportion of DFNB1-associated deafness amongst the Portuguese implanted individuals. DFNB1 status is significantly associated to higher oral performance scores, with DFNB1 individuals performing, on average, 6% better than the individuals without DFNB1-associated deafness.

Bilateral cochlear implantation: current concepts, indications, and results

The optimal treatment for bilateral hearing loss continues to evolve as cochlear implant (CI) and hearing aid technologies advance, as does our understanding of the central auditory system. Ongoing discussions continue on the validity and feasibility of bilateral CI in terms of performance, justification of need, medical/surgical safety concerns, and economics. The purpose of this review article is to provide an update on the advantages and disadvantages of bilateral CI and to provide a discussion on timing (simultaneous vs. sequential), technology (bimodal vs. binaural) and feasibility. Binaural advantages are found in both adult and pediatric bilateral CI recipients, the greatest being the head shadow effect and improvements in localization and loudness summation. This theoretically offers an advantage over their unilateral implanted counterparts in terms of improved sound localization and enhanced speech perception under noisy conditions. Most investigators agree that bilateral stimulation during critical periods of development is paramount for optimizing auditory functioning in children. Currently, bilateral CI is widely accepted as a safe and effective means of bilateral auditory stimulation.

Spinogenesis and pruning in the primary auditory cortex of the macaque monkey (Macaca fascicularis): an intracellular injection study of layer III pyramidal cells

Recently we demonstrated that neocortical pyramidal cells in visual, visual association and prefrontal cortex of the macaque monkey are characterised by different growth, branching, spinogenesis and pruning during development. Some neurons, such as those in the primary visual area, prune more spines than they grow following sensory onset, while others such as those in area TE grow more than they prune. To what extent these different neuronal growth profiles may vary among cortical areas remains to be determined. To better comprehend the nature and extent of these regional differences in pyramidal cell growth profiles we expanded the bases for comparison by studying neurons in the primary auditory cortex (A1). We found that pyramidal cells in A1 continue to grow their basal dendritic trees beyond the peak period of spinogenesis (3(1)/(2) months) up until at least 7 months of age. Likewise, the most prolific branching patterns were observed in the dendritic trees of pyramidal cells at 7 months of age. These data reveal that the basal dendritic trees of cells in A1 continue to grow for a much longer period, and attain almost double the number of spines, as compared with those in V1. Such differences in the growth profiles of neocortical pyramidal cells among cortical areas may influence therapeutic outcomes when applying new technologies such as neurotrophic delivery devices or stem cell therapy.

Análise comparativa da linguagem oral de crianças ouvintes e surdas usuárias de implante coclear

OBJETIVO: analisar e comparar a expressão verbal de crianças ouvintes e crianças usuárias de implante coclear. MÉTODOS: os participantes foram 12 crianças ouvintes, entre 4 anos e 2 mês e 4 anos e 11 meses, e 10 crianças portadoras de perda auditiva neurossensorial profunda, usuárias de implante coclear, de 4 anos e 3 meses a 5 anos e 0 meses. As crianças foram avaliadas por meio da Escala de Expressão Verbal da Reynell Developmental Language Scales (RDLS), versão americana, adaptada por Fortunato-Queiroz (2007). Os dados dos dois grupos de crianças foram analisados e comparados entre si. RESULTADOS: as crianças surdas obtiveram um desempenho inferior ao das crianças ouvintes quanto à expressão verbal. Três crianças implantadas obtiveram resultados próximos ao considerado como padrão pela pesquisa, ou seja, aos resultados das crianças ouvintes. CONCLUSÃO: os resultados obtidos pelas crianças deficientes auditivas, usuárias de IC, foram inferiores aos seus pares ouvintes. As crianças surdas que apresentaram as maiores pontuações foram as que possuíam maior tempo de uso do IC e menor tempo de privação sensorial.

Long term outcomes of early cochlear implantation in Korea

Objectives

The objective of this study was to compare the long-term auditory performance and language skill depending on the age of cochlear implantation in the Korean population. We especially tried to separate the effect of maturation/development from that of the age at implantation.

Methods

Eighty-six pre-lingual children with profound hearing loss who underwent a cochlear implantation before the age of six and had been followed for more than 3 yr were included in this study prospectively. Categories of Auditory Performance (CAP) and Korean Picture Vocabulary Test (K-PVT) were serially followed up. In order to separate the age at implantation effect, K-PVT results were readjusted to the child's chronological age in the normal hearing population.

Results

When the CAP and K-PVT scores were directly compared without chronological readjustment, we failed to show a significant difference for improvements according to the age at implantation. Early cochlear implantation was associated with better language development, only when the K-PVT scores were readjusted to percentile scores of their chronological age.

Conclusion

Early cochlear implantation was associated with better language development even within the critical period. This advantage may be recognized only when the effect of the age at implantation is separated from the effect of maturation/development.

Melodic contour identification and music perception by cochlear implant users

Research and outcomes with cochlear implants (CIs) have revealed a dichotomy in the cues necessary for speech and music recognition. CI devices typically transmit 16-22 spectral channels, each modulated slowly in time. This coarse representation provides enough information to support speech understanding in quiet and rhythmic perception in music, but not enough to support speech understanding in noise or melody recognition. Melody recognition requires some capacity for complex pitch perception, which in turn depends strongly on access to spectral fine structure cues. Thus, temporal envelope cues are adequate for speech perception under optimal listening conditions, while spectral fine structure cues are needed for music perception. In this paper, we present recent experiments that directly measure CI users' melodic pitch perception using a melodic contour identification (MCI) task. While normal-hearing (NH) listeners' performance was consistently high across experiments, MCI performance was highly variable across CI users. CI users' MCI performance was significantly affected by instrument timbre, as well as by the presence of a competing instrument. In general, CI users had great difficulty extracting melodic pitch from complex stimuli. However, musically experienced CI users often performed as well as NH listeners, and MCI training in less-experienced subjects greatly improved performance. With fixed constraints on spectral resolution, such as occurs with hearing loss or an auditory prosthesis, training and experience can provide considerable improvements in music perception and appreciation.

Cochlear Implant Outcomes for Children With Auditory Neuropathy Spectrum Disorder

Cochlear implantation is currently the intervention option of choice for many children with auditory neuropathy spectrum disorder (ANSD) who are unable to obtain benefit from conventional amplification. The aim of this study was to review the speech perception and language outcomes for children with ANSD who had received a cochlear implant and highlight specific clinical considerations for working with this population of children with hearing impairment who are being considered for implantation. Finds for the group of 17 children with ANSD using cochlear implants were compared to previously reported outcomes for children with sensori-neural (SN) type hearing loss using cochlear implants.

Two children, identified with cochlear nerve deficiency pre-operatively, received no useful auditory percepts from their cochlear implant and discontinued device use. The remaining children demonstrated speech perception and language outcomes comparable to those observed for SN hearing loss peers using cochlear implants.

This paper highlights a number of considerations for clinicians to be aware of and the importance of careful counseling pre-operatively regarding the potential for less-than-optimal outcomes, particularly for those children identified with cochlear nerve deficiency.

What to do with the other ear after cochlear implantation

Unilateral cochlear implantation has become a widely accepted surgical intervention for both deaf children and adults. It is a reliable and effective method to rehabilitate profound deafness. Recently the benefits of the use of a contralateral hearing aid (bimodal stimulation) with a cochlear implant became clear. Bilateral cochlear implantation benefits bilateral input into the auditory system for adults and children. To provide the binaural advantages experienced by normal hearing subjects bilateral cochlear implantation or bimodal stimulation is probably indicated. Whether to choose between both possibilities depends on many factors. Cortical auditory evoked potential (CAEP) measurements can be an important tool to decide bilateral implantation in young children. Enough residual hearing in the non-implanted ear might benefit from bimodal stimulation. New protocols are needed for the audiological management for recipients of cochlear implants.

Language achievement in children who received cochlear implants between 1 and 2 years of age: group trends and individual patterns

This study examined receptive and expressive vocabulary and grammar achievement of French-speaking children (n = 27) who received a cochlear implant (CI) between the age of 1 and 2. Standardized measures of language achievement were administered and the language levels attained by children with CIs were compared with that of the normative sample of same-age hearing peers for each measure. As a group, children exhibited language levels within normal limits in all standardized language measures. Examination of individual patterns revealed four different language profiles ranging from normal language levels in all domains to general language delay. Half the participants displayed language levels on par with similar-age peers at the word level; less than half the children obtained average performance at the sentence level. In three of these profiles, comprehension of sentences was impaired. Moreover, the age at implantation was not associated with language achievement. Findings suggest that receiving a CI between the age of 1 and 2 years does not ensure that language abilities will be within normal limits after up to 6 years of experience with the implant.

Three-Year Postimplantation Auditory Outcomes in Children with Sequential Bilateral Cochlear Implantation

Objectives:

We report on the auditory abilities and speech performance in quiet and noise of 35 children with sequential bilateral cochlear implantation after 3 years of bilateral implant use.

Methods:

Testing was done in bilateral and both unilateral listening conditions. The assessments took place before the second implantation and at several time intervals after fitting. As different auditory tests were used, the children were categorized by their age at the second implantation: Younger or older than 6 years.

Results:

The pure tone averages for the bilateral condition were significantly better than those for either unilateral condition after 12 months of bilateral implant use and remained so from that test interval onward. The speech recognition outcomes in quiet and noise also improved significantly for almost all children after 36 months, although a linear regression analysis showed a beneficial effect of younger age at first implantation on the speech-in-noise results.

Conclusions:

Bilateral cochlear implantation offered advantages to all children in comparison with the first implant — Even the children who received the second implant after the age of 6 years. Compared to the younger children, the older children needed a longer adjustment period to gain bilateral benefit. However, they obtained similar results after 2 years of bilateral implant use.

Progress in restoration of hearing with the auditory brainstem implant

Fifty years ago auditory scientists were very skeptical about the potential of new prosthetic approaches that electrically stimulated the auditory nerve, the cochlear nuclei (CN), and the inferior colliculus (IC). In those decades, the basilar membrane was considered to play a fundamental and irreplaceable role as a fine spectrum analyzer in hearing physiology, and therefore it was thought that electrical stimulation of the auditory system would have never produced functionally useful hearing. Over the last 30 years, cochlear implants (CIs) have improved steadily to the point where the average sentence recognition with modern multichannel devices is better than 90% correct. More recently, similar performance has been observed with electric stimulation of the brainstem with auditory brainstem implants (ABIs). However, it is clear that to fully understand hearing and to design the next generation of prosthetic devices we must better understand the ear-brain relationship. Indeed some aspects of hearing do not require the intricate complexities of cochlear physiological responses, while other auditory tasks rely critically on specialized details of cochlear processing. The progress in electrical stimulation of the central auditory system requires us to reconsider the patient selection criteria for different implant devices, in particular to evaluate the possibility of ABIs for etiologies with poor outcomes with CIs. In the present review, the latest outcomes in restoration of hearing with ABI are presented. New guidelines are proposed for device selection for different etiologies and future research is suggested to further refine the process of matching an individual patient to the most appropriate implant device.

Fricatives, affricates, and vowels in Croatian children with cochlear implants

The aim of the research was to analyse the speech of children with cochlear implants over approximately a 46-month period, and compare it with the speech of hearing controls. It focused on three categories of sounds in Croatian: vowels (F1 and F2 of /i/, /e/, /a/, /o/ and /u/), fricatives /s/ and /integral/ (spectral differences expressed in terms of center of gravity), and affricates /ts/ and /t integral/ (accuracy, total duration, and pattern of stop-fricative components). One group of subjects were 10 implanted children who had been profoundly deaf before implantation. There were four recordings per child. Group two children were hearing controls matched for age and sex. The results show that the implanted children are closest to unimpaired children in terms of their formant-defined vowel space. Their fricatives exhibit poor distinction in terms of the noise spectrum, and the affricates are the most difficult to produce.

Outcomes in bilateral cochlear implantation

OBJECTIVE

The objective of this study was to explore improvements in quality of life and the cost-utility of bilateral cochlear implantation.

STUDY DESIGN AND SETTING

A prospective case-control study was conducted on 23 bilateral cochlear implant patients with the Mark III health utility index.

RESULTS

Results indicate a 0.48 mean gain in health utility after bilateral cochlear implantation and a discounted cost per quality adjusted life year of $24,859 in this cohort of patients. With a comparison of patient scores for unilateral and bilateral use, improvements in the domains of hearing, speech, emotion, and cognition were noted, resulting in a mean gain in health utility of 0.11.

CONCLUSIONS

This study found an improvement in quality of life and a favorable cost-utility associated with bilateral cochlear implantation in patients with profound hearing loss. These patients showed additional improvements in quality of life after they received their second implant.

CLINICAL SIGNIFICANCE

This is the first study that showed improvements in quality of life and a favorable cost-utility after bilateral cochlear implantation in patients with profound hearing loss.

Universal newborn hearing screening: systematic review to update the 2001 US Preventive Services Task Force Recommendation

OBJECTIVE

This review is an update for the US Preventive Services Task Force on universal newborn hearing screening to detect moderate-to-severe permanent, bilateral congenital hearing loss. We focus on 3 key questions: (1) Among infants identified by universal screening who would not be identified by targeted screening, does initiating treatment before 6 months of age improve language and communication outcomes? (2) Compared with targeted screening, does universal screening increase the chance that treatment will be initiated by 6 months of age for infants at average risk or for those at high risk? (3) What are the adverse effects of screening and early treatment?

METHODS

Medline and Cochrane databases were searched to identify articles published since the 2002 recommendation. Data from studies that met inclusion criteria were abstracted, and studies were rated for quality with predetermined criteria.

RESULTS

A good-quality retrospective study of children with hearing loss indicates that those who had early versus late confirmation and those who had undergone universal newborn screening versus none had better receptive language at 8 years of age but not better expressive language or speech. A good-quality nonrandomized trial of a large birth cohort indicates that infants identified with hearing loss through universal newborn screening have earlier referral, diagnosis, and treatment than those not screened. These findings are corroborated by multiple descriptive studies of ages of referral, diagnosis, and treatment. Usual parental reactions to an initial nonpass on a hearing screen include worry, questioning, and distress that resolve for most parents. Cochlear implants have been associated with higher risks for bacterial meningitis in young children.

CONCLUSIONS

Children with hearing loss who had universal newborn hearing screening have better language outcomes at school age than those not screened. Infants identified with hearing loss through universal screening have significantly earlier referral, diagnosis, and treatment than those identified in other ways.

Variable long-term outcomes from cochlear implantation in children with hypoplastic auditory nerves

This paper describes the outcomes in six children with hypoplastic cochlear nerves, demonstrated on magnetic resonance imaging who were selected for implantation because they had clear responses to sound, with hearing aids. In four of the six children the internal auditory canals were abnormally narrow; however in the remaining two the internal auditory canals were of normal width. After activation of their devices, all six children had auditory thresholds within the normal range for implanted congenitally deaf children. However the progress of all these children after 2 to 6 years of implant use turned out to be disappointing. Five of the children developed only the ability to detect the presence of sound, and were unable to discriminate accurately between speech sounds. They remain at Category of Auditory Performance (CAP) level 2: sign is their primary mode of communication. All five children also remain at Speech Intelligibility Rating (SIR) level 2, with unintelligible connected speech. The sixth child was able to develop some understanding of common phrases through listening alone, however he remains at CAP level 4 and his SIR level also remains at 2. The benefit of cochlear implantation in this group of children is likely to be considerably restricted. In specific cases it may be appropriate to offer a cochlear implant to a child with hypoplastic auditory nerves but careful counselling of the family about likely outcomes is essential.

Expected test scores for preschoolers with a cochlear implant who use spoken language

PURPOSE

The major purpose of this study was to provide information about expected spoken language skills of preschool-age children who are deaf and who use a cochlear implant. A goal was to provide "benchmarks" against which those skills could be compared, for a given age at implantation. We also examined whether parent-completed checklists of children's language were correlated with results of standardized language tests and whether scores increased linearly with decreasing age of implantation and increasing duration of cochlear implant use.

METHOD

Participants were a nationwide sample of 76 children who were deaf and orally educated and who received an implant by 38 months of age. Formal language tests were administered at age 4.5 years. The MacArthur-Bates Communicative Development Inventories (CDI) instrument was completed by parents when children were ages 3.5 and 4.5 years.

RESULTS

Based on regression analyses, expected scores for each age at implant were provided for 2 commonly administered language tests at 4.5 years of age and CDI subscale scores at 3.5 and 4.5 years. Concurrent test scores were significantly correlated on all measures. A linear relation was found that predicted increasing test scores with younger ages at implantation for all scales administered.

CONCLUSIONS

While the expected scores reported here should not be considered as normative data, they are benchmarks that may be useful for evaluating spoken language progress of children with cochlear implants who are enrolled in spoken language-based programs.

[Cochlear implant: hearing and language in pre-lingual deaf children]

BACKGROUND

Cochlear implant in children, speech perception and oral language, hearing and oral language performance in children with pre-lingual profound sensory-neural hearing impairment, users of cochlear implant.

AIM

To study the hearing and oral language performance of children with pre-lingual bilateral profound sensory neural hearing impairment, users of multi-channel cochlear implant considering the following aspects: age of the child when the research was carried out, time of hearing sensorial privation, time of cochlear implant use, type of cochlear implant, type of speech coding strategy used, familial permeability level in relation to the therapeutic process and cognitive style of the child.

METHOD

Participants of this study were 60 children who were assessed according to hearing and language categories. All of the variables were statistically analyzed. Psycho-social aspects, considering the child's cognitive style and the family's permeability level were also assessed.

RESULTS

Regarding the hearing and language performance with the use of cochlear implant, the intermediate and advanced hearing categories were accomplished by more than half of the children. The statistically significant aspects in the performance of hearing and oral language were: the age of the child upon evaluation, time of hearing sensorial privation, time of cochlear implant use, type of implant, speech sounds coding strategy and familial permeability.

CONCLUSION

The cochlear implant as a treatment for children with pre-lingual sensory-neural hearing impairment is highly effective, although complex, owing to the interaction of variables which interfere in the implanted child's performance. Further studies are needed for the understanding of the implantation complexity in young children.

[Oral language of children with five years of experience using [corrected] cochlear implant]

BACKGROUND

Cochlear implant (CI) in children.

AIM

1) to delineate a profile of receptive and expressive verbal language of children who have been using cochlear implant for five years and five years and eleven months; 2) to verify the influence of time of auditory sensorial privation in the receptive and expressive verbal language of these children.

METHOD

19 children users of CI with auditory deficiency acquired before language development, who have been using CI for 5y - 5y11m and who have an average time of sensorial privation of 3y (standard deviation of 1 year). These children were assessed using the Reynell Developmental Scales (RDLS) (Reynell e Gruber, 1990) which is composed of: Comprehension Scale (C), Expression Scale (E) and its Structure Sub-Scales (Es), Vocabulary (Ev) and Content (Ec).

RESULTS

The median values and the values found for quartile 75 and quartile 25 were: .44, 57 and 54 for C; 48, 60 and 55 for E; 20, 21 and 20 for Es; 15, 19 and 17 for Ev; 15, 22 and 18 for Ec; 96, 116 and 108 for the total score. A statistical correlation between the time of sensorial privation and the score obtained for C (p=- 0.62; R=0.0044) and Ec (p=-0.48; R=0.0348) was observed. Therefore the time of sensorial privation had an influence on the overall score (p=- 0.53; R=0.0174).

CONCLUSION

The language profile of children who use CI for five years is devious and similar to that of five year old hearing children regarding Expression and to that of four year old hearing regarding Comprehension; time of sensorial privation was statistically significant for the score obtained in C--receptive language--and for the score obtained in the E section (Ec)--expressive language, as well as in the overall score of RDLS.

Executive function and language in deaf children

The relationship between language and executive function (EF) and their development in children have been the focus of recent debate and are of theoretical and clinical importance. Exploration of these functions in children with a peripheral hearing loss has the potential to be informative from both perspectives. This study compared the EF and language skills of 8- to 12-year-old children with cochlear implants (n = 22) and nonimplanted deaf children (n = 25) with those of age-matched hearing controls (n = 22). Implanted and nonimplanted deaf children performed below the level of hearing children on tests assessing oral receptive language, as well as on a number of EF tests, but no significant differences emerged between the implanted and nonimplanted deaf groups. Language ability was significantly positively associated with EF in both hearing and deaf children. Possible interpretations of these findings are suggested and the theoretical and clinical implications considered.

Deaf children with cochlear implants before the age of 1 year: comparison of preverbal communication with normally hearing children

OBJECTIVES

To compare preverbal behaviors of deaf children implanted under 1 year of age with age-matched hearing children.

METHODS

The study assessed 20 children; 10 deaf children implanted under 1 year of age and 10 normally hearing children of the same age. Preverbal skills were measured before, 6 months, and 1 year after implantation, using Tait Video Analysis that is able to predict later speech outcomes in young implanted children.

RESULTS

Regarding vocal turns, the normally hearing group outperformed the implanted group although the latter children became quite vocal, nearly 60% of their turns being taken in this way. The mean vocal autonomy in implanted children, 1 year after implantation, was very close to the respective of hearing children (38.5 versus 43.5). Regarding the non-looking vocal turns, by the 12-month interval, hearing children had somewhat higher scores than implanted children, but the difference was not significant and the increase in implanted children was much higher (40-fold increase versus 4-fold increase). However, implanted children were more likely to use silent communication than hearing children, although gestural turns were decreasing with time.

CONCLUSIONS

The small numbers in this study, although two of the largest European cochlear implant centers were combined to recruit such young implantees, led us to be cautious in interpreting the results. However, it seems that in deaf implanted children under 1 year of age, some preverbal communication behaviors are developing to an extent (although at a somewhat lower level) not significantly different from those of age-matched normally hearing children.

Ten-Year Follow-Up of a Consecutive Series of Children With Multichannel Cochlear Implants

OBJECTIVES

To assess a group of children who consecutively received implants more than 10 years after implantation with regard to speech perception, speech intelligibility, receptive language level, and academic/occupational status.

STUDY DESIGN

A prospective longitudinal study.

SETTING

Pediatric referral center for cochlear implantation.

PATIENTS

Eighty-two prelingually deafened children received the Nucleus multichannel cochlear implant.

INTERVENTIONS

Cochlear implantation with Cochlear Nucleus CI22 implant.

MAIN OUTCOME MEASURES

The main outcome measures were open-set Phonetically Balanced Kindergarten word test, discrimination of sentences in noise, connective discourse tracking (CDT) using voice and telephone, speech intelligibility rating (SIR), vocabulary knowledge measured using the Peabody Picture Vocabulary Test (Revised), academic performance on French language, foreign language, and mathematics, and academic/occupational status.

RESULTS

After 10 years of implant experience, 79 children (96%) reported that they always wear the device; 79% (65 of 82 children) could use the telephone. The mean scores were 72% for the Phonetically Balanced Kindergarten word test, 44% for word recognition in noise, 55.3 words per minute for the CDT, and 33 words per minute for the CDT via telephone. Thirty-three children (40%) developed speech intelligible to the average listener (SIR 5), and 22 (27%) developed speech intelligible to a listener with little experience of deaf person's speech (SIR 4). The measures of vocabulary showed that most (76%) of children who received implants scored below the median value of their normally hearing peers. The age at implantation was the most important factor that may influence the postimplant outcomes. Regarding educational/vocational status, 6 subjects attend universities, 3 already have a professional activity, 14 are currently at high school level, 32 are at junior high school level, 6 additional children are enrolled in a special unit for children with disability, and 3 children are still attending elementary schools. Seventeen are in further noncompulsory education studying a range of subjects at vocational level.

CONCLUSION

This long-term report shows that many profoundly hearing-impaired children using cochlear implants can develop functional levels of speech perception and production, attain age-appropriate oral language, develop competency level in a language other than their primary language, and achieve satisfactory academic performance.

Will they catch up? The role of age at cochlear implantation in the spoken language development of children with severe to profound hearing loss

PURPOSE

The authors examined the benefits of younger cochlear implantation, longer cochlear implant use, and greater pre-implant aided hearing to spoken language at 3.5 and 4.5 years of age.

METHOD

Language samples were obtained at ages 3.5 and 4.5 years from 76 children who received an implant by their 3rd birthday. Hierarchical linear modeling was used to identify characteristics associated with spoken language outcomes at the 2 test ages. The Preschool Language Scale (I. L. Zimmerman, V. G. Steiner, & R. E. Pond, 1992) was used to compare the participants' skills with those of hearing age-mates at age 4.5 years.

RESULTS

Expected language scores increased with younger age at implant and lower pre-implant thresholds, even when compared at the same duration of implant use. Expected Preschool Language Scale scores of the children who received the implant at the youngest ages reached those of hearing age-mates by 4.5 years, but those children implanted after 24 months of age did not catch up with hearing peers.

CONCLUSION

Children who received a cochlear implant before a substantial delay in spoken language developed (i.e., between 12 and 16 months) were more likely to achieve age-appropriate spoken language. These results favor cochlear implantation before 24 months of age, especially for children with aided pure-tone average thresholds greater than 65 dB prior to surgery.

Age and outcome of cochlear implantation for patients with bilateral congenital deafness in a Cantonese-speaking population

OBJECTIVE

To evaluate the effect of age at implantation by assessment of speech perception in cochlear implant users with bilateral congenital deafness.

DESIGN

A retrospective cohort analysis of 60 cochlear implant users (age at implantation, 1.01 to 22.0 yr) who have at least 2 yr of experience. Their outcome performance was defined by the change in i) speech perception category (SPC) score based on postoperative assessment results and ii) the type of education attended after implantation. The association of age at implantation with SPC scores was analyzed at different ages at implantation (2, 3, 4, 5, and 6 yr old). The SPC scores for a particular age at implantation were compared at 6, 12, and 24 mo after implantation. The impact of age at implantation on choice of education was evaluated by analyzing the transition from a school for the deaf to mainstream education for the 45 children who were operated on before the age of 10, because older children are less likely to make such a change.

RESULTS

Children implanted at the ages of 2, 3, 4, 5, and 6 yr all obtained significant improvements in SPC scores 24 mo after implantation. The greatest improvement was noted at 24 mo after implantation among those operated on before age 3. For all age groups, improvement at 24 mo after implantation is greater than at 12 mo, whereas the latter is greater than the improvement noted at 6 mo after implantation. Comparison of children implanted before the age of 3 and between ages 3 and 10 showed a significant difference in the choice of education after implantation. Children who were implanted before the age of 3 were more likely to attend mainstream education after implantation.

CONCLUSION

Results from the present study are consistent with the current belief that implantation at a younger age provides greater benefit. The proportion of children attending mainstream education was significantly higher for those implanted before age 3, which may be a potential benefit to early implantation for relieving the burden of governments in providing special education.