Pediatric cochlear implantation: candidacy evaluation, medical and surgical considerations, and expanding criteria

Preoperative Assessment Using CT and MRI Scans of the Temporal Bone to Determine the Degree of Difficulty in Cochlear Implant Surgery

Background Cochlear implant surgery is a complex procedure influenced by the anatomical structures of the temporal bone. Preoperative imaging using CT and MRI can provide critical insights into the surgical challenges that may be encountered. This study aims to evaluate the role of CT and MRI in preoperative assessment to predict the difficulty of cochlear implant surgery in terms of surgical time. Materials and methods A retrospective observational study was conducted at Saveetha Medical College and Hospital, Chennai, from April 2022 to September 2023. Ninety patients with severe to profound sensorineural hearing loss who underwent cochlear implantation were included. Preoperative high-resolution CT (HRCT) and MRI of the temporal bone were performed to assess various anatomical parameters. Surgical difficulty was evaluated intraoperatively and correlated with preoperative imaging findings. Data were analyzed using IBM SPSS Statistics for Windows, V. 21.0 (IBM Corp., Armonk, NY). Results The mean age of participants was 7.4±10.9 years, with the majority (66.7%) in the 1-5-year age group. Out of 90 participants, 50 were male and 40 were female. HRCT and MRI revealed that 35.6% of participants had hypo-/non-pneumatized mastoids, 3.3% had narrow facial recesses, and 3.3% had high-riding jugular bulbs. Significant correlations were found between surgical time and associated congenital (p=0.006) and acquired (p=0.0001) anomalies of the temporal bone, as well as the total difficulty score (p=0.0001). The mean surgical time was 103.97±25.2 minutes, with a range from 45 to 220 minutes. Conclusion Preoperative HRCT and MRI are valuable tools in predicting the degree of difficulty in cochlear implant surgery. Specific anatomical features identified in imaging studies can significantly influence the surgical approach and duration. These findings underscore the importance of detailed preoperative imaging to enhance surgical planning and outcomes in cochlear implant procedures.

Current Issues With Pediatric Cochlear Implantation

Cochlear implants (CIs) have demonstrated a clear functional benefit in children with severe-to-profound sensorineural hearing loss (SNHL) and thus have gained wide acceptance for treating deafness in the pediatric population. When evaluating young children for cochlear implantation, there are unique considerations beyond the standard issues addressed during surgery in adults. Because of advances in genetic testing, imaging resolution, CI technology, post-implant rehabilitation, and other factors, issues related to CI surgery in children continue to evolve. Such factors have led to changes in candidacy guidelines, vaccine requirements, and lowering of age requirement for surgery. In addition, differences in the anatomy and physiology of infants require special attention to ensure safety when operating on young children. This review summarizes these issues and provides guidance for surgeons treating children with SNHL.

Temporal Trends in Early Pediatric Cochlear Implantations in California from 2018 to 2020

OBJECTIVE

To characterize the demographics of children receiving cochlear implantations, identify factors associated with delayed implantations, and trend these factors over time.

DESIGN

Retrospective cross-sectional study.

SETTING

Healthcare Cost and Utilization Project California State Ambulatory Surgery Database for calendar years 2018-2020.

PATIENTS

Children 5 years or younger undergoing cochlear implantation.

INTERVENTIONS

Cochlear implantation.

MAIN OUTCOMES MEASURES

The population-controlled number of cochlear implantations was calculated and stratified by race and insurance. Early implantation was defined as implantation at age 2 years or younger. A mixed-effects logistic regression model was generated to identify factors associated with early implantation and how that association changed from 2018 to 2020.

RESULTS

The final cohort included 467 children. The number of implantations increased from 141 to 175 implants from 2018 to 2020 (24.1% increase); 229 (49.0%) children were implanted at 2 years or younger. Medicaid insurance was associated with decreased odds of early implantation (odds ratio, 0.18 [95% confidence interval, 0.15-0.23], p < 0.001); this association with Medicaid insurance was significant when stratified across all racial groups. The percentage of children with Medicaid who were implanted at 2 years or younger increased from 20.9 to 62.0% from 2018 to 2020.

CONCLUSIONS AND RELEVANCE

Among children in California, socioeconomic factors, in particular public insurance, are correlated with age of cochlear implantation. These disparities improved significantly from 2018 to 2020. Further investigation into changes and initiatives in California during this time frame may aid in directing national efforts to improve pediatric cochlear implantation access.

The role for cochlear implants in microtia and congenital aural atresia: A case report and a review of literature

Sensorineural hearing loss resulting from microtia and aural atresia is rare due to different embryologic origins of the external and inner ear. Consequently, cochlear implants are seldom performed in patients with microtia and/or aural atresia. Herein we discuss an 8 year-old boy with congenital aural atresia and microtia who underwent cochlear implant surgery for profound hearing loss with good results. A literature review was performed and discussed. Pre-operative planning with high resolution computed tomography and facial nerve monitoring are crucial in identification and preservation of the facial nerve due to the high rate of aberrant anatomy. Careful incision placement is required particularly if pinna reconstruction is considered. Literature review highlighted various surgical approaches as well as different modalities used for intra-operative facial nerve monitoring. Only one patient had intra-operative complications. Cochlear implant is a viable solution in patients with external ear malformations and severe-profound sensorineural hearing loss. Adequate planning and counselling are essential due to the challenges that may occur in microtia and aural atresia.

Early grammar-building in French-speaking deaf children with cochlear implants: A follow-up corpus study

BACKGROUND

One of the most consistent findings reported in the paediatric cochlear implant (CI) literature is the heterogeneity of language performance observed more in grammatical morphology than in lexicon or pragmatics. As most of the corpus studies addressing these issues have been conducted in English, it is unclear whether their results can be generalized to other languages. In particular, little is known about languages known for their grammatical complexity, such as French.

AIMS

The aim of this corpus study was to compare the productive use of function words (FWs) and some agreement features (AGRs) in children with CIs and children with typical development (TD) matched for mean length of utterance in words (MLU_words ), a general index of grammatical complexity, and auditory experience, as measured by hearing age (HA) and chronological age (CA), respectively.

METHODS & PROCEDURES

Natural speech samples from 116 monolingual French-speaking children, including 40 children with CIs followed longitudinally and 76 TD children, were collected. FWs and AGRs were analysed using a Part of Speech Tagger (POS-T) from the Child Language Data Exchange System (CHILDES).

OUTCOMES & RESULTS

The two groups differed by 3 years for HA and CA. No effect of family socio-economic status (SES) was found in the CI group. Stepwise regression analyses showed that the two groups did not share the same predictors of MLU_words : plurals and determiners predicted MLU_words in children with CIs, at 2 and 3 years of HA, whereas feminine markers and subject-pronouns were found to best predict MLU_words in TD children at 2 and 3 years of CA. Structural equation models (SEMs), a combination of confirmatory factor analysis (CFA) and path analysis, yielded a different hierarchical structure of grammatical relations (GRs). Selective difficulties affecting verbal clitics and other pronominal forms were found specifically in the CI group (object-pronouns, reflexive, relative and past participles). Dependency grammar analysis confirmed these contrasting developmental profiles in multiword utterances, such as preposition/nouns, subject/verbs, and verb/determiner/nouns.

CONCLUSIONS & IMPLICATIONS

Atypical grammatical patterns in children with CIs reflect a specific architecture of syntactic dependencies of FWs underpinning morphological complexity and syntactic connectivity. Clinical implications are discussed for assessment and intervention planning.

WHAT THIS PAPER ADDS

What is already known on this subject The productive use of FWs has been identified as a particular area of weakness in children with CIs compared with TD children. In addition, heterogenous grammatical performance has often been found after 1-3 years of CI use, regardless of demographic factors such as age at implantation, duration of deafness or SES. What this paper adds to existing knowledge Assessing the early building of FWs and AGRs in children with CIs helps to understand the syntactic complexity and hierarchical structure of their language. Since most corpus studies on grammatical morphology have been conducted in English, it is not clear whether their difficulties can be generalized to other languages. The French language has a system of FWs and inflections that determine the morphophonological properties of nominal and verbal forms. Early grammar learning in children with CIs born with profound deafness were compared with the two groups of TD children matched both for duration of auditory experience (i.e., HA of CI children, CA of TD children) and for MLU_words . We found a similar profile between groups at 2 years but not at 3 years for HA and CA. The two groups do not share the same predictors of MLU_words : namely, plurals and determiners for CI children versus feminine markers and subject pronouns for TD children. They show a different syntactic organization of GRs. Children with CIs struggle with selective difficulties affecting verbal clitics and pronominal forms (object-pronouns, reflexive, relative and past participles). Consistent with theories of morphophonological richness and syntactic connectivity, our results support the distributional learning hypothesis of language acquisition that infants and toddlers are sensitive to FWs and AGRs at an early age. Specific components of syntactic organization are disrupted in children with CIs. What are the potential or actual clinical implications of this work? This work has potential clinical implications because it unravels the limitations of morphophonological processing in children with CIs. Its results highlight a specific difficulty in learning FWs and AGRs in a verbal inflectional morphology context.

Trends in Timing and Provision of Pediatric Cochlear Implant Care During COVID‐19

Objectives

To identify trends in timing of pediatric cochlear implant (CI) care during COVID-19.

Study Design

Retrospective cohort.

Setting

Tertiary care center.

Methods

Patients under 18 years of age who underwent CI between 1/1/2016 and 2/29/2020 were included in the pre-COVID-19 group, and patients implanted between 3/1/2020 and 12/31/2021 comprised the COVID-19 group. Revision and sequential surgeries were excluded. Time intervals between care milestones including severe-to-profound hearing loss diagnosis, initial CI candidacy evaluation, and surgery were compared among groups, as were the number and type of postoperative visits.

Results

A total of 98 patients met criteria; 70 were implanted pre-COVID-19 and 28 during COVID-19. A significant increase in the interval between CI candidacy evaluation and surgery was seen among patients with prelingual deafness during COVID-19 compared with pre-COVID-19 (µ = 47.3 weeks, 95% confidence interval [CI]: 34.8-59.9 vs µ = 20.5 weeks, 95% CI: 13.1-27.9; p < .001). Patients in the COVID-19 group attended fewer in-person rehabilitation visits in the 12 months after surgery (µ = 14.9 visits, 95% CI: 9.7-20.1 vs µ = 20.9, 95% CI: 18.1-23.7; p = .04). Average age at implantation in the COVID-19 group was 5.7 years (95% CI: 4.0-7.5) versus 3.7 years in the pre-COVID-19 group (95% CI: 2.9-4.6; p = .05). The time interval between hearing loss confirmation and CI surgery was on average 99.7 weeks for patients implanted during COVID-19 (95% CI: 48.8-150) versus 54.2 weeks for patients implanted pre-COVID (95% CI: 39.6-68.8), which was not a statistically significant difference (p = .1).

Conclusion

During the COVID-19 pandemic patients with prelingual deafness experienced delays in care relative to patients implanted before the pandemic.

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.

Hearing Protection Outcomes of Analog Electrode Arrays Coated with Different Drug-Eluting Polymer Films Implanted into Guinea Pig Cochleae

Objective

To investigate the hearing protection outcomes of different drug-eluting analog electrode arrays implanted into guinea pig cochleae.

Methods

Sixty guinea pigs were randomly divided into a negative control group and five experimental groups implanted separately with blank (drug carrier), dexamethasone (DXM), aracytine (Ara-C), Ara-C+DXM, and nicotinamide adenine dinucleotide (NAD+) eluting analog electrode arrays. Micro CT was used to supervise the surgical procedure. Auditory brainstem response (ABR) thresholds of the guinea pigs were measured and analyzed.

Results and Conclusions

Compared with the negative control, all other groups showed a significant increase in ABR threshold (p<0.001) after surgery. Among them, there was no obvious difference between the blank (0 vs 90 days: 59.70±10.57 vs 64.60±9.47 dB SPL) and the NAD+ group (0 vs 90 days: 59.90±9.87 vs 64.70±8.65 dB SPL). On the other hand, the ABR thresholds in the DXM (0 days: 58.10±10.73 dB SPL; 90 days: 51.70±9.07 dB SPL) and the Ara-C group (0 days: 59.00±10.05 dB SPL; 90 days: 51.60±8.48 dB SPL) decreased significantly compared with the former two groups (p<0.001). However, the Ara-C+DXM group showed no further benefit (p>0.05). In addition, a significantly higher survival rate of spiral ganglion neurons in cochleae was observed in the Ara-C and/or DXM groups.

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.

Cochlear Implant Outcomes in Large Vestibular Aqueduct Syndrome-Should We Provide Cochlear Implants Earlier?

OBJECTIVE

Examine postoperative speech perception outcomes in a large vestibular aqueduct syndrome (LVAS) patients at a major cochlear implantation center.

STUDY DESIGN

Retrospective analysis of the Sydney Cochlear Implant Centre (SCIC) database and medical records from January 1994 to December 2015 was performed.

SETTING

Tertiary referral center.

PATIENTS

Patients with a diagnosis of LVAS who received a cochlear implant (CI). Only those with speech perception outcomes recorded at least 12 months post implant were included in our analysis.

INTERVENTION(S)

Therapeutic.

MAIN OUTCOME MEASURE(S)

Postoperative speech perception scores.

RESULTS

Between 1994 and 2015, 176 adult and pediatric patients with a diagnosis of LVAS underwent cochlear implantation at SCIC. Postoperative Bamford-Kowal Bench (BKB) sentence test scores were obtained for 97 patients. The postoperative median BKB score was 93% with a lower quartile score of 85% and an upper quartile score of 98%. Smaller numbers were available for post-CI City University of New York (CUNY) and Consonant-Nucleus-Consonant (CNC) word scores yet similar excellent results were seen.

CONCLUSIONS

Our study results suggest the CI should be considered when BKB scores have dropped to 85%. We suggest that rather than LVAS cases representing a challenge to cochlear implantation, they are amongst the best candidates for surgery, and should receive a CI at an earlier stage in hearing loss, when they have better speech perception. This allows stable hearing to be established earlier along with excellent speech perception outcomes.

Sound-Field Speech Evoked Auditory Brainstem Response in Cochlear-Implant Recipients

Background and Objectives

Currently limited information is available on speech stimuli processing at the subcortical level in the recipients of cochlear implant (CI). Speech processing in the brainstem level is measured using speech-auditory brainstem response (S-ABR). The purpose of the present study was to measure the S-ABR components in the sound-field presentation in CI recipients, and compare with normal hearing (NH) children.

Subjects and Methods

In this descriptive-analytical study, participants were divided in two groups: patients with CIs; and NH group. The CI group consisted of 20 prelingual hearing impairment children (mean age=8.90 ± 0.79 years), with ipsilateral CIs (right side). The control group consisted of 20 healthy NH children, with comparable age and sex distribution. The S-ABR was evoked by the 40-ms synthesized /da/ syllable stimulus that was indicated in the sound-field presentation.

Results

Sound-field S-ABR measured in the CI recipients indicated statistically significant delayed latencies, than in the NH group. In addition, these results demonstrated that the frequency following response peak amplitude was significantly higher in CI recipients, than in the NH counterparts (p<0.05). Finally, the neural phase locking were significantly lower in CI recipients (p<0.05).

Conclusions

The findings of sound-field S-ABR demonstrated that CI recipients have neural encoding deficits in temporal and spectral domains at the brainstem level; therefore, the sound-field S-ABR can be considered an efficient clinical procedure to assess the speech process in CI recipients.

Cochlear Implantation in Congenital Long-QT Syndrome: A Comprehensive Study

OBJECTIVES

Jervell and Lange-Nielsen syndrome is a rare autosomal recessive disease characterized by congenital sensorineural deafness and significant QT interval prolongation. Aims were to study the prevalence of long QT in congenital hearing loss, complications encountered, outcomes by Categories of auditory Performance (CAP) scores and Speech Intelligibility Rating (SIR) scores and to create an algorithm with precautions to be followed in Long QT children.

MATERIALS AND METHODS

Study was done at Auditory implant center at a tertiary referral care ENT hospital which includes 41 paediatric patients who were diagnosed to have Long QT during preoperative assessment and underwent cochlear implantation. A standard Protocol was followed in all candidates which includes comprehensive targeted history and investigations, preoperative and intraoperative precautions, and the findings were recorded.

RESULTS

Preoperative prophylactic Beta blockers, avoiding sympathetic stimulation and drugs prolonging QT interval with rational use of Magnesium Sulphate and standby of defibrillator were the standard precautions practised. Fatal Arrhythmias were encountered intra-operatively in five patients which was treated with cardiac pacing. Cardiac monitoring was done intraoperatively and during switch-on. Significant improvement in CAP and SIR scores were observed at 3 and 6 months when compared to their base line values.

CONCLUSION

With special attention to preoperative evaluation, appropriate intraoperative precautions and monitoring, judicious surgical planning and post surgical follow-up cochlear implantation may be performed safely in patients with JLNS with good postoperative results allowing for improved audition.

Categorization of everyday sounds by cochlear implanted children

Auditory categorization is an important process in the perception and understanding of everyday sounds. The use of cochlear implants (CIs) may affect auditory categorization and result in poor abilities. The current study was designed to compare how children with normal hearing (NH) and children with CIs categorize a set of everyday sounds. We tested 24 NH children and 24 children with CI on a free-sorting task of 18 everyday sounds corresponding to four a priori categories: nonlinguistic human vocalizations, environmental sounds, musical sounds, and animal vocalizations. Multiple correspondence analysis revealed considerable variation within both groups of child listeners, although the human vocalizations and musical sounds were similarly categorized. In contrast to NH children, children with CIs categorized some sounds according to their acoustic content rather than their associated semantic information. These results show that despite identification deficits, children with CIs are able to categorize environmental and vocal sounds in a similar way to NH children, and are able to use categorization as an adaptive process when dealing with everyday sounds.

Which imaging modality in cochlear implant candidates?

PURPOSE

There is no guideline or consensus on preoperative radiologic imaging modality despite the fact that it has a vital importance in appropriate candidacy selection of cochlear implantation. We aimed to find out the role of high-resolution computed tomography (HRCT) and magnetic resonance imaging (MRI) on surgical planning, intraoperative technique in cochlear implant candidates.

METHODS

The clinical charts, imagings, and operative reports of patients who underwent cochlear implant surgery at a tertiary institution were retrospectively examined.

RESULTS

611 patients (503 children and 108 adult) were enrolled into the study. We found 11 different pathologies in MRI which could not be seen in HRCT. However, we decided the side of surgery according to MRI in only three of them in which the pathology was cochlear nerve hypoplasia. Two patients with cochlear nerve hypoplasia were children with prelingual deafness and one was adult with perilingual deafness. Moreover, we changed the surgical planning of side according to both imaging modalities in nine patients. Seven of them were children and two were adult. One of these adults had cochlear anomaly, and another had bilateral temporal bone fracture.

CONCLUSIONS

We suggest both imaging modalities in pediatric candidates. However, in adults, we think that superiority of either imaging modalities is still contradictive. We had only three adult patients and the decision of the side of surgery was made according to MRI in one of them and to both imaging modalities in the other two adults.

Satisfaction with Life among Mothers of Pediatric Cochlear Implant Candidates: The Impact of Implant Operation and Sociodemographic Factors

OBJECTIVES

To evaluate the satisfaction with life among mothers of pediatric cochlear implant candidates regarding implant surgery and sociodemographic factors.

MATERIALS AND METHODS

Mothers of 160 pediatric patients with profound sensorineural hearing loss who underwent unilateral cochlear implant surgery were included. A questionnaire form with items on sociodemographic-familial characteristics and Satisfaction with Life Scale (SWLS) was employed via face-to-face interview method before and 12 months after the implant surgery.

RESULTS

The SWLS scores significantly improved after the implant surgery [from 19.1 (7.0) to 28.9 (4.0), p<0.000]. Being unemployed vs. employed [17.9 (6.9) vs. 24.0 (5.3), p=0.000], having another child with hearing disability [13.5 (5.7) vs. 19.7 (6.9), p=0.001], younger (12-24 months) vs. older (>24 months) age of the child at the time of implant surgery [7.1 (0.4) vs. 19.7 (6.6), p=0.001], absence vs. presence of regular follow-up visits [13.0 (0.0) vs. 19.4 (7.1), p=0.002], and presence vs. absence of change in social life after the diagnosis of disease [17.3 (6.5) vs. 20.9 (7.1), p=0.001] were associated with significantly lower SWLS scores among mothers. SWLS scores were positively correlated with patient's age at the time of implant surgery (r=0.206, p=0.009), whereas negatively correlated with the number of household members (r=-0.406, p=0.000) and number of children (r=-0.310, p=0.000).

CONCLUSION

In conclusion, our findings revealed the association of cochlear implantation with a significant increase in mother's life satisfaction, despite the unemployment, presence of another child with hearing disability, and crowded household. Our findings emphasize on the consideration of family systems with special attention to mother's emotional experiences and occupational competence in the intervention programs.

Rare case of bilateral aural atresia and cochlear dysplasia: when cochlear implantation is not the answer

OBJECTIVE AND IMPORTANCE

Reports of patients with concurrent middle and inner ear anomalies are rare. These patients present a surgical challenge for cochlear implantation. The surgical risk must be weighed against the predicted benefit of the patient's hearing outcome and subsequent development of speech and language as well as their quality of life.

CLINICAL PRESENTATION

Thirteen-year-old boy presented to the Otology clinic for auditory rehabilitation options. He has mild developmental delay, is non-verbal and communicates via American Sign Language. He was born with bilateral aural atresia and never wore amplification. On exam he has grade 1 microtia and complete ear canal atresia bilaterally. His behavioural hearing test shows profound sensorineural hearing loss of both ears. The computed tomography scan shows bilateral underdeveloped and completely opacified mastoid and middle ear, complete bony atresia of the ear canals, and an under-partitioned cochlea with poorly defined modiolus, among other abnormalities. The patient and his family were counselled on the available options as well as the need for any further studies.

INTERVENTION

Counselling of patient and family.

CONCLUSION

While there have been reports in the literature of performing cochlear implantations in patients with a concurrent atresia and cochlear dysplasia, these were patients whose degree of inner ear anomalies was relatively minor and their prognosis of a good audiological outcome was favourable. The presented case is that of a patient for whom the surgical approach to the cochlea alone would be difficult. More importantly, his quality of life would not significantly improve in light of the predicted limited hearing and language development outcomes, given the severity of his inner ear abnormalities, limited communication abilities, prolonged period of deafness and developmental delays.

Facial nerve anomalies in paediatric cochlear implant candidates: radiological evaluation

Background:

Pre-operative radiological identification of facial nerve anomalies can help prevent intra-operative facial nerve injury during cochlear implantation. This study aimed to evaluate the incidence and configuration of facial nerve anomalies and their concurrence with inner-ear anomalies in cochlear implant candidates.

Methods:

Inner-ear and concomitant facial nerve anomalies were evaluated by magnetic resonance imaging and temporal high-resolution computed tomography in 48 children with congenital sensorineural hearing loss who were cochlear implant candidates.

Results:

Inner-ear anomalies were present in 11 out of 48 patients (23 per cent) and concomitant facial nerve anomalies were present on 7 sides in 4 patients (7 per cent of the total). Facial nerve anomalies were accompanied by cochlear or vestibular malformation.

Conclusion:

Potential facial nerve abnormalities should always be considered in patients with inner-ear anomalies. Pre-operative facial nerve imaging can increase the surgeon's confidence to plan and perform cochlear implantation. Magnetic resonance imaging should be used to detect inner-ear anomalies; if these are identified, temporal high-resolution computed tomography should be used to evaluate the facial nerve.

Temporal High-Resolution Computed Tomography and Magnetic Resonance Imaging of Congenital Inner Ear Anomalies in Children

Imaging plays an important role in determining indications of cochlear implantation and choosing candidates for the procedure in children. Temporal high-resolution computed tomography (HRCT) and magnetic resonance imaging (MRI) can display precisely the complex anatomic structure of inner ear. Although HRCT permits detailed imaging of bony structures, MRI gives valuable information about membranous labyrinth, internal acoustic canal, and vestibulocochlear nerve. Magnetic resonance imaging examination of the brain should be performed at the same time to evaluate any coexistent brain parenchymal abnormality. These imaging modalities are complementary methods in evaluating congenital inner ear anomalies. The aim of this pictorial essay is to reviewing temporal HRCT and MRI findings of congenital inner ear anomalies.

Effects of Removing Low-Frequency Electric Information on Speech Perception With Bimodal Hearing

PURPOSE

The objective was to determine whether speech perception could be improved for bimodal listeners (those using a cochlear implant [CI] in one ear and hearing aid in the contralateral ear) by removing low-frequency information provided by the CI, thereby reducing acoustic-electric overlap.

METHOD

Subjects were adult CI subjects with at least 1 year of CI experience. Nine subjects were evaluated in the CI-only condition (control condition), and 26 subjects were evaluated in the bimodal condition. CIs were programmed with 4 experimental programs in which the low cutoff frequency (LCF) was progressively raised. Speech perception was evaluated using Consonant-Nucleus-Consonant words in quiet, AzBio sentences in background babble, and spondee words in background babble.

RESULTS

The CI-only group showed decreased speech perception in both quiet and noise as the LCF was raised. Bimodal subjects with better hearing in the hearing aid ear (< 60 dB HL at 250 and 500 Hz) performed best for words in quiet as the LCF was raised. In contrast, bimodal subjects with worse hearing (> 60 dB HL at 250 and 500 Hz) performed similarly to the CI-only group.

CONCLUSIONS

These findings suggest that reducing low-frequency overlap of the CI and contralateral hearing aid may improve performance in quiet for some bimodal listeners with better hearing.

Prevalence of various etiologies of hearing loss among cochlear implant recipients: Systematic review and meta-analysis

OBJECTIVE

To investigate the etiology of deafness in cochlear implanted children and to address the question whether there is a need for more thorough diagnostics, especially concerning genetics.

DESIGN

Systematic review. Four databases were searched for studies (year 2000-2014) on cochlear implanted children (n > 100). Studies were excluded if etiology had influenced their inclusion criteria. Eligibility and methodological quality were assessed independently by three authors. The studies' description of diagnostic evaluation was categorized in three groups.

STUDY SAMPLE

Sixteen studies were included (5069 children).

RESULTS

The most common etiological categories were 'Unknown' 40.3% (95% CI 32.8 to 48.0), 'Non-syndromic' 22.4% (95% CI 17.1 to 28.2), and 'Postnatal' 11.3% (95% CI 7.2 to 16.2). Studies published after 2006 had a lower proportion of 'Unknown' etiology 35.3% (95% CI 28.0 to 42.8) than older 45.5% (95% CI 31.0 to 60.4). Important information was missing from several studies: 11 (69%) studies did not provide detailed description on diagnostic evaluation of the etiology of deafness and had a higher proportion of 'Unknown' etiology.

CONCLUSIONS

In order to ensure a higher level of comparability in future studies, we recommend agreement upon an international standard of diagnostics and the introduction of an international standard for reporting etiology.

The role of preoperative imaging for cochlear implantation in postlingually deafened adults

BACKGROUND

Preoperative imaging is standard practice for cochlear implant candidacy. Postlingually deafened adults rarely have temporal bone abnormalities that alter management.

OBJECTIVES/HYPOTHESIS

To determine the role of preoperative imaging for cochlear implantation in postlingually deafened adults. We hypothesize that imaging does not alter management in the absence of history or physical examination findings suggestive of an anatomic abnormality.

STUDY DESIGN

Nested case-control study.

METHODS

We identified postlingually deafened adults with preoperative imaging and cochlear implantation at our institution from 1995 to 2008. Controls had a negative history and normal exam. Cases had suggestive history or exam. Imaging studies and operative records were reviewed.

RESULTS

Approximately 164 patients met inclusion criteria-59 cases and 109 controls. Mean age at onset of hearing loss was 30.4 years (range, 0-73 yr), mean age at onset of deafness was 54.1 years (range, 9-89 yr), and mean age at implantation was 61.5 years (range, 20.6-89.7 yr). Twenty cases (34%) and 17 controls (16%) had abnormal imaging (p = 0.001). Six cases (8.5%) and 2 controls (1.8%) had changes in their management as a result of the imaging findings (p = 0.023). Both control patients had incidentally detected acoustic neuromas, which altered the side of the cochlear implantation. There was a strong association between preoperative history and exam findings and abnormality on imaging (p = 0.007). Abnormalities were 3 times more likely in patients with a positive history or exam (OR = 2.98; 95% CI, 1.36-6.54).

CONCLUSION

In patients with a negative history and examination, imaging rarely alters management. MRI may detect incidental vestibular schwannomas in patients with asymmetric hearing losses.

LEVEL OF EVIDENCE

3b, Individual case-control study.

Cochlear Implantation in Children With Autism Spectrum Disorder

OBJECTIVE

To assess the outcome of cochlear implantation in children with autism spectrum disorder (ASD).

STUDY DESIGN

Retrospective case review and survey.

SETTING

Tertiary referral center.

PATIENTS

Children who meet criteria for cochlear implantation and diagnosis of ASD.

MAIN OUTCOME MEASURES

Receptive and expressive language scores and parental survey data.

RESULTS

Fifteen patients with history of ASD and cochlear implantation were analyzed and compared with 15 patients who received cochlear implant and have no other disability. Postoperatively, more than 67% of children with ASD significantly improved their speech perception skills, and 60% significantly improved their speech expression skills, whereas all patients in the control group showed significant improvement in both aspects. The top 3 reported improvements after cochlear implantation were name recognition, response to verbal requests, and enjoyment of music. Of all behavioral aspects, the use of eye contact was the least improved. Survey results in regard to improvements in patient interaction were more subtle when compared with those related to sound and speech perception. The most improved aspects in the ASD patients' lives after cochlear implantation seemed to be attending to other people's requests and conforming to family routines. Of note, awareness of the child's environment is the most highly ranked improvement attributed to the cochlear implant.

CONCLUSION

Cochlear implants are effective and beneficial for hearing impaired members of the ASD population, although development of language may lag behind that of implanted children with no additional disabilities. Significant speech perception and overall behavior improvement are noted.

Why repetition? Repetitive babbling, auditory feedback, and cochlear implantation

This study investigated the reduplicated, or repetitive vocalizations of hearing infants and infants with profound hearing loss with and without cochlear implants using a new measure of repetition in order to address questions not only about the effects of cochlear implantation on repetitive babbling, but also about the reason repetitive vocalizations occur at all and why they emerge around 7 or 8 months of age in hearing infants. Participants were 16 infants with profound hearing loss and 27 hearing infants who participated at a mean age of 9.9 months and/or a mean age of 17.7 months. Mean age at cochlear implantation for infants with profound hearing loss was 12.9 months, and mean duration of implant use was 4.2 months. The data show that before cochlear implantation, repetitive vocalizations were rare. However, 4 months after cochlear implant activation, infants with hearing loss produced both repetitive vocalizations and repetitions per vocalization at levels commensurate with their hearing peers. The results support the hypothesis that repetition emerges as a means of vocal exploration during the time when hearing infants (and infants with cochlear implants) form auditory-motor representations and neural connections between cortical areas active in syllable production and syllable perception, during the transition from nonlinguistic to linguistic vocalization.

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.

Pediatric cochlear implantation: an update

Deafness in pediatric age can adversely impact language acquisition as well as educational and social-emotional development. Once diagnosed, hearing loss should be rehabilitated early; the goal is to provide the child with maximum access to the acoustic features of speech within a listening range that is safe and comfortable. In presence of severe to profound deafness, benefit from auditory amplification cannot be enough to allow a proper language development. Cochlear implants are partially implantable electronic devices designed to provide profoundly deafened patients with hearing sensitivity within the speech range. Since their introduction more than 30 years ago, cochlear implants have improved their performance to the extent that are now considered to be standard of care in the treatment of children with severe to profound deafness. Over the years patient candidacy has been expanded and the criteria for implantation continue to evolve within the paediatric population. The minimum age for implantation has progressively reduced; it has been recognized that implantation at a very early age (12-18 months) provides children with the best outcomes, taking advantage of sensitive periods of auditory development. Bilateral implantation offers a better sound localization, as well as a superior ability to understand speech in noisy environments than unilateral cochlear implant. Deafened children with special clinical situations, including inner ear malformation, cochlear nerve deficiency, cochlear ossification, and additional disabilities can be successfully treated, even thogh they require an individualized candidacy evaluation and a complex post-implantation rehabilitation. Benefits from cochlear implantation include not only better abilities to hear and to develop speech and language skills, but also improved academic attainment, improved quality of life, and better employment status. Cochlear implants permit deaf people to hear, but they have a long way to go before their performance being comparable to that of the intact human ear; researchers are looking for more sophisticated speech processing strategies as well as a more efficient coupling between the electrodes and the cochlear nerve with the goal of dramatically improving the quality of sound of the next generation of implants.

[Magnetic resonance imaging in patients with magnetic hearing implants: overview and procedural management]

BACKGROUND

Every year in Germany approximately 3,500 patients receive a cochlear implant or other hearing implants with an implantable magnet. At the same time more and more patients are examined by magnetic resonance imaging (MRI). For the indications and execution of this imaging modality a number of restrictions and safety measures have to be considered.

METHODS

This article is based on the restrictions of the manufacturers and a selective literature search in PubMed using the following keywords: MRI compatibility/MRI safety + cochlea implant/auditory brainstem implant/Bonebridge/Carina/Esteem/Otomag/Sophono alpha/Vibrand Soundbridge. We included all 20 publications of this search concerning the MRI compatibility of the hearing implants complemented by papers cited in the primary articles.

RESULTS

High electromagnetic field intensities as used in MRI can cause malfunction and dislocation of the implant or the magnet in the device. Older cochlear implants (CI) and the current CIs produced by Advanced bionics without explantation of the magnet, some CI models produced by the company Cochlear and the middle ear implants Carina®/Esteem® (older models) and Vibrant-Soundbridge® are not approved for MRI examinations. Other hearing prostheses are approved for 0.2 T, 1.0 T or 1.5 T MRI and in exceptional circumstances 3 T MRI. Recommendations of the manufacturers have to be followed, notably wearing a head bandage during the imaging procedure. The longitudinal axis of the patient's head has to be to positioned parallel to the main magnetic field of the scanner. The patient may not move the head laterally during the examination. Possible artefacts and the reduced validity of the results of skull MRI have to be considered when evaluating the indications for the examination.

CONCLUSION

For patients wearing hearing implants with an implantable magnet the indications for MRI in devices with MRI certification should be rigorously restricted. Possible defects/dislocation of the implants may occur and the quality of the skull MRI images is reduced. A close contact between the radiologist and the implanting team is required. Other diagnostic procedure options should be exhausted before employing MRI.

Frequency of vocalization before and after cochlear implantation: dynamic effect of auditory feedback on infant behavior

The motivation for infants' non-word vocalizations in the second half of the first year of life and later is unclear. This study of hearing infants and infants with profound hearing loss with and without cochlear implants addressed the hypothesis that vocalizations are primarily motivated by auditory feedback. Early access to cochlear implants has created unique conditions of auditory manipulation that permit empirical tests of relations between auditory perception and infant behavior. Evidence from two separate tests of the research hypothesis showed that, before cochlear implantation, infants with profound hearing loss vocalized significantly less often than hearing infants; however, soon after cochlear implantation, they vocalized at levels commensurate with hearing peers. In contrast, vocal behaviors that are typically considered reflexive or emotion-based signals (e.g., crying) were infrequent overall and did not vary with auditory access. These results support the hypothesis that auditory feedback is a critical component motivating early vocalization frequency.

Cochlear implantation in children with cochlear nerve deficiency

OBJECTIVE

The aim of this study was to report on auditory performance after cochlear implantation in children with cochlear nerve deficiency.

METHODS

A retrospective case review was performed. Five patients with pre-lingual profound sensorineural hearing loss implanted in an ear with cochlear nerve deficiency participated in the study. Postoperative auditory and speech performance was assessed using warble tone average threshold with cochlear implant, speech perception categories, and speech intelligibility ratings. All patients underwent high resolution computed tomography and magnetic resonance imaging.

RESULTS

According to Govaerts classification, three children had a type IIb and two a type IIa cochlear nerve deficiency. Preoperatively, four patients were placed into speech perception category 1 and one into category 2. All patients had an improvement in hearing threshold with the cochlear implant. Despite this, at the last follow-up (range 18-81 months, average 45 months), only one girl benefited from cochlear implantation; she moved from speech perception category 2 to 6 and developed spoken language. Another child developed closed set speech perception and had connected speech that was unintelligible. The other 3 children showed little benefit from the cochlear implant and obtained only an improved access to environmental sounds and improved lipreading skills. None of these 4 children developed a spoken language, but they were all full-time users of their implants.

CONCLUSIONS

The outcomes of cochlear implantation in these five children with cochlear nerve deficiency are extremely variable, ranging from sporadic cases in which open set speech perception and acquisition of a spoken language are achieved, to most cases in which only an improved access to environmental sound develops. Regardless of these limited outcomes, all patients in our series use their device on a daily basis and derive benefits in everyday life. In our opinion, cochlear implantation can be a viable option in children with cochlear nerve deficiency, but careful counseling to the family on possible restricted benefit is needed.

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.

Cochlear implantation in unique pediatric populations

PURPOSE OF REVIEW

Over the last decade, the selection criteria for cochlear implantation have expanded to include children with special auditory, otologic, and medical problems. Included within this expanded group of candidates are those children with auditory neuropathy spectrum disorder, cochleovestibular malformations, cochlear nerve deficiency, associated syndromes, as well as multiple medical and developmental disorders. Definitive indications for cochlear implantation in these unique pediatric populations are in evolution. This review will provide an overview of managing and habilitating hearing loss within these populations with specific focus on cochlear implantation as a treatment option.

RECENT FINDINGS

Cochlear implants have been successfully implanted in children within unique populations with variable results. Evaluation for cochlear implant candidacy includes the core components of a full medical, audiologic, and speech and language evaluations. When considering candidacy in these children, additional aspects to consider include disorder-specific surgical considerations and child/caregiver counseling regarding reasonable postimplantation outcome expectations.

SUMMARY

Cochlear implants are accepted as the standard of care for improving hearing and speech development in children with severe-to-profound hearing loss. However, children with sensorineural hearing loss who meet established audiologic criteria for cochlear implantation may have unique audiologic, medical, and anatomic characteristics that necessitate special consideration regarding cochlear implantation candidacy and outcome. Individualized preoperative candidacy and counseling, surgical evaluation, and reasonable postoperative outcome expectations should be taken into account in the management of these 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.

The auditory and speech performance of children with intellectual disability after cochlear implantation

CONCLUSION

The results revealed that children with intellectual disability (ID) who underwent cochlear implantation (CI) showed gradual progress in their auditory perception and speech development. ID in children should not be considered a contraindication for CI, because they are able to obtain a chance to develop oral communication skills following CI.

OBJECTIVE

The purpose of this study was to assess the auditory and speech performance of 14 young deaf children with ID after CI.

METHODS

Fourteen children with ID who underwent CI between December 2002 and February 2010 were included. Improvement in auditory perception and speech production over time was evaluated longitudinally with the Categories of Auditory Performance (CAP) score and Korean version of Ling's stages (K-Ling). The results were compared with those of age- and gender-matched implanted controls without additional disabilities. All tests were performed four times in each patient: before implantation and at 3, 6, and 12 months after implantation. Preoperative and postoperative communication modes were also assessed and compared between the two groups.

RESULTS

Auditory perception and speech production of deaf children with an ID improved consistently after CI. In addition, the communication mode also took a favorable turn from nonverbal to vocalizations or oral communication or from vocalizations to oral communication.