Cochlear implantation in children with auditory neuropathy spectrum disorder

Comparison of Cochlear Implant Efficacy in Pre- Versus Postsynaptic Auditory Neuropathy: A Systematic Review

Background: Etiological factors affecting outcomes of cochlear implants (Cis) are known; however, a direct comparison of efficacy based on lesion location is needed. We aimed to systematically examine the current evidence to compare the effectiveness of CIs in patients with presynaptic versus postsynaptic neuropathy. Methods: A comprehensive literature search was conducted across multiple databases, including MEDLINE (via PubMed), Embase, CENTRAL, Web of Science, Scopus, CINAHL, and PsycINFO. Studies were selected based on their examination of CI efficacy in patients with auditory neuropathy spectrum disorder, distinguishing between pre- and postsynaptic lesions using genetic markers or electrophysiological assessments. Results: Analysis of seven studies consistently highlighted the importance of etiological diagnosis in predicting CI outcomes. Genetic mutations were correlated with more favorable CI outcomes, emphasizing the role of genetic etiology. Electrophysiological measures also proved useful in assessing auditory function, further emphasizing the value of detailed diagnostics. Conclusion: Etiological factors generally influence CI outcomes; however, the success varies between pre- and postsynaptic neuropathies. Integrating genetic and electrophysiological diagnostics is crucial for predicting CI performance, suggesting a need for personalized approaches in evaluating CI candidates for more targeted and effective auditory rehabilitation.

Brazilian Society of Otology task force - cochlear implant ‒ recommendations based on strength of evidence

OBJECTIVE

To make evidence-based recommendations for the indications and complications of Cochlear Implant (CI) surgery in adults and children.

METHODS

Task force members were educated on knowledge synthesis methods, including electronic database search, review and selection of relevant citations, and critical appraisal of selected studies. Articles written in English or Portuguese on cochlear implantation were eligible for inclusion. The American College of Physicians' guideline grading system and the American Thyroid Association's guideline criteria were used for critical appraisal of evidence and recommendations for therapeutic interventions.

RESULTS

The topics were divided into 2 parts: (1) Evaluation of candidate patients and indications for CI surgery; (2) CI surgery - techniques and complications.

CONCLUSIONS

CI is a safe device for auditory rehabilitation of patients with severe-to-profound hearing loss. In recent years, indications for unilateral hearing loss and vestibular schwannoma have been expanded, with encouraging results. However, for a successful surgery, commitment of family members and patients in the hearing rehabilitation process is essential.

Cochlear Implantation in Pediatric Cochlear Nerve Deficiency: A Systematic Review and Meta-Analysis

OBJECTIVE

Cochlear nerve deficiency (CND) is commonly implicated in moderate-to-profound pediatric sensorineural hearing loss (SNHL). Although cochlear implantation (CI) was previously contraindicated in CND patients, recent studies have demonstrated the potential for auditory response to CI in a subset of CND patients, though clinical outcomes remain variable. This study aims to evaluate pre- and postoperative speech and auditory outcomes of CI in pediatric patients with bilateral SNHL and radiographically confirmed CND.

DATA SOURCES

Embase and Ovid MEDLINE.

REVIEW METHODS

A systematic review was conducted to identify studies reporting pre- and postoperative outcomes of children with CND confirmed by magnetic resonance imaging who underwent CI. A random-effects model was used to account for within- and between-study variance in speech and auditory outcomes.

RESULTS

After abstract screening of 818 distinct articles, 16 studies were selected for final inclusion, consisting of 248 patients with cochlear nerve hypoplasia or aplasia who underwent CI. Various speech perception and language development tests were investigated across studies (Speech Intelligibility Rating, Speech Perception Category, Speech Awareness Thresholds, Meaningful Auditory Integration Scale, Meaningful Use of Speech Scale, Categories of Auditory Performance, and Auditory Level). Pooled outcomes demonstrated improvement in speech perception after CI in pediatric patients with CND (SMD 2.18, 95% CI 1.68-2.69).

CONCLUSION

Indications for CI are expanding as research demonstrates benefit in populations previously thought inappropriate. Our study demonstrates global postoperative improvement in speech and auditory outcomes in children with bilateral SNHL and CND after CI.

LEVEL OF EVIDENCE

NA Laryngoscope, 2024.

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

PURPOSE

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

METHOD

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

RESULTS

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

CONCLUSION

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

SUPPLEMENTAL MATERIAL

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

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

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

Assessing Neural Synchrony in the Cochlear Nerve to Electrical Stimulation in Children With Auditory Neuropathy Spectrum Disorder

OBJECTIVES

This study reported phase locking values (PLVs) that quantified the trial-to-trial phase coherence of electrically evoked compound action potentials in children with auditory neuropathy spectrum disorders (ANSD) and children with Gap Junction Beta 2 (GJB2) mutations, a patient population without noticeable cochlear nerve damage.

DESIGN

PLVs were measured at three electrode locations in 11 children with ANSD and 11 children with GJB2 mutations. Smaller PLVs indicated poorer neural synchrony. A linear mixed-effects model was used to compare PLVs measured at different electrode locations between participant groups.

RESULTS

After controlling for the stimulation level effect, children with ANSD had smaller PLVs than children with GJB2 mutations at all three electrode locations.

CONCLUSIONS

Cochlear-implanted children with ANSD show poorer peripheral neural synchrony than children with GJB2 mutations.

A systematic review on the imaging findings in auditory neuropathy spectrum disorder

Purpose

The present systematic review examined imaging findings in the Auditory Neuropathy Spectrum Disorder (ANSD) population.

Methods

Electronic databases such as Pub Med, Google Scholar, J Gate, and Science Direct were used to conduct a literature search. The articles retrieved through the literature search were assessed in two stages. In the first stage, title and abstract screening were done; in the second stage, a full-length article review was done. From the 379 shortlisted records, 19 articles were chosen for the full-length review.

Results

The selected articles performed imaging using Computerized tomography (CT) and magnetic resonance imaging (MRI). In most studies, cochlear nerve deficiency (CND) was the most prevalent anomaly in the ANSD group. Also, MRI was the imaging modality of choice recommended in most studies. It was also noted that CND was a characteristic feature of unilateral ANSD.

Conclusion

From this systematic review, it is clear that integrating imaging studies into diagnostic protocol would help to understand the underlying pathology better and expedite decision-making and intervention for ANSD patients.

Outcomes of Cochlear Implant Recipient With ANSD: Intra and Post Operative Findings, Progress in Audition and Speech Skills

Introduction

Auditory neuropathy spectrum disorder (ANSD) is a distinct type of SNHL that is characterized by the presence of otoacoustic emissions and/or cochlear microphonics. Cochlear implantation was initially not recommended for ANSD children, later studies showed variable outcomes among ANSD. CI is currently the intervention option of choice for many children with ANSD who are unable to obtain benefit from conventional amplification.

Aim and Objectives

To review experiences with some of the preoperative and postoperative findings in a child who was diagnosed with auditory neuropathy and provided with cochlear implant. To describe changes in auditory function, which enabled to have significant improvement in hearing and communication skills through auditory verbal therapy (AVT) and regular follow ups.

Study Design

Pre and postoperative, findings in cochlear implant recipient who was diagnosed with ANSD. Child received complete medical examinations, including related consultations in audiology, otorhinolaryngology, paediatrics, neurology, psychology, speech language pathology, and radiology.

Methodology/Case Report

A 3-year-old-female have brought to the hospital with a C/o not responding to sounds, name call and unable to speak. Medical and Audiological evaluations were initiated. The hearing assessments of the child included appropriate behavioural audiometric techniques, objective measures of middle ear function, acoustic reflex studies, transient evoked (TEOAE), distortion product (DPOAE) otoacoustic emissions and auditory brainstem responses (ABR). Implanted with (HiRes Ultra CI HiFocus SlimJ Electrode), and objective measures were recorded intraoperatively electrode impedances and neural response telemetry (NRT) to assess the outcomes technically. These intraoperative objective measures were used to help program the speech processor for the child. Postoperatively, child has had regular follow-up with otorhinolaryngologist to assure complete healing of the surgical incision, to assess their general medical conditions, and audiologist for switch-on (speech processor) followed by mapping. The hearing and communication skills have been assessed, also continued Auditory Verbal Therapy (AVT) on a regular basis. Postoperatively, objective measures were recorded in regular intervals and monitored with therapy outcomes.

Results

 The child has shown significant improvement in sound detection, speech perception abilities, communication skills and shown evidence of progression of good NRT results, which  were recorded and had no postoperative complications.

Conclusion

 Experience with cochlear implantation for child diagnosed with ANSD that effectively received and benefited from CI. A detailed and careful evaluations, audiological follow-ups and tailored rehabilitation plans, can be considered as a beneficial management approach for CI, especially who diagnosed with ANSD. The regular use of cochlear implant in this diagnosis can lead to a clear increase in speech comprehension, development and overall progress in quality of life. Success or lack of success with a CI appears to be somewhat dependent on the specific site of lesion (pre- or post-synaptic). Currently there are no clinical measures available to diagnose the specific site of lesion. Indeed, CI appears to be an effective rehabilitation modality for ANSD patients. This may be explained by the fact that the implanted electrode delivers synchronized electrical impulses directly to the auditory nerve, bypassing the presynaptic IHCs and its synapse involved in the unsynchronized firing of the auditory nerve described in ANSD. However, genetic studies that have proven to be essential in the knowledge of underlying mechanisms of ANSD represent a promising therapeutic approach in the management of ANSD.

Cochlear implantation in children with auditory neuropathy spectrum disorder: an updated systematic review

BACKGROUND

The goal of managing auditory neuropathy spectrum disorder (ANSD) is to restore the children's ability to discriminate auditory information. Children who are not making sufficient progress in speech comprehension, and speech and language development after receiving adequate auditory re/habilitation and/or acoustic amplification may be candidates for cochlear implantation (CI). Despite the growing number of published literature on CI outcomes in children with ANSD, the current evidence is primarily based on case reports or retrospective chart reviews some of which had a limited number of children. In addition, the outcomes of CI seem to vary between children with ANSD. Thus, compelling evidence is lacking. This updated systematic review evaluated the speech perception, language, and speech intelligibility outcomes of children with ANSD post-CI.

METHODS

An online bibliographic search was conducted in PubMed, Scopus, Web of Science, and CENTRAL databases. We included both interventional and observational studies that assessed the outcomes of the CI in  children with ANSD.

RESULTS

Thirty-three studies were included in this systematic review. Several tests were used to assess speech perception following CI in children with ANSD. The findings of this study revealed that  children with ANSD had mean Categories of Auditory Performance scores ranging from 4.3 to 7 post-operatively, this result was better than the pre-operative scores which ranged between 0.4 to 2.5. Likewise, the Infant-Toddler Meaningful Auditory Integration Scale, Phonetically Balanced Kindergarten, and multisyllabic lexical neighborhood test showed clinically relevant improvement after CI. The same findings were reported for language and speech intelligibility scores. One study investigated the quality of life/children satisfaction after CI and showed overall good satisfaction with the outcomes.

CONCLUSIONS

The present systematic review suggests that CI is a feasible and effective hearing  rehabilitation modality for children with ANSD.

REGISTRATION AND PROTOCOL

PROSPERO ID: CRD42021279140.

Indicators for cochlear implantation in children with auditory neuropathy spectrum disorder: A systematic review

PURPOSE

ANSD refers to a group of auditory diseases demonstrating intact outer hair cells and desynchronized neural firings of the auditory nerve. A cochlear implant is a promising intervention strategy for severe to profound sensorineural hearing loss (SNHL). However, due to its variable outcomes in children with ANSD, a consensus has yet to be reached on its performance. This study aimed to review the literature to determine the efficacy of cochlear implants in children with ANSD and to determine prognostic indicators. The study identifies the pre-operative and post-operative predictors of success for CI in children with ANSD.

METHOD

The review was carried out using PRISMA guidelines. This resulted in 9630 topic-related articles. Among these, 17 articles met the inclusion and exclusion criteria that were included for the study. The quality and potential risks associated with each article were evaluated using the quality impact assessment protocol (QUIPS) tool.

RESULTS

A review of 17 articles was conducted to highlight these predictors. Most selected studies included case reports, case series, cohorts, and comparisons between children with ANSD and SNHL. Assessment of study quality reported an overall low risk of bias. The overall result showed cochlear implant would be an effective option for children with ANSD. However, there are specific prognostic indicators about which clinician needs to be aware before recommending CI for children with ANSD. Our review study identified a set of pre-operative and post-operative indicators that predicted speech and auditory performance and gave some insight into the lesion site in ANSD individuals.

CONCLUSION

This review concludes CI is an effective option for children with ANSD. However, before recommending CI, a detailed assessment is required from different perspectives, which could serve as predictors of postoperative outcomes. This review highlights the need to include more precise tools, such as genetic testing to describe the lesion site to choose the most appropriate management strategy for children with ANSD. Knowledge about the prognostic indicators and the effective assessment protocols would help clinicians for the better candidacy selection.

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

PURPOSE

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

METHOD

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

RESULTS

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

CONCLUSIONS

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

Cochlear implantation programming characteristics and outcomes of cochlear nerve deficiency

PURPOSE

Due to the specificity of cochlear implantation (CI) programming parameters and outcomes in cochlear nerve deficiency (CND) patients, this study aimed to investigate the correlation between programming parameters and outcomes and further compare the difference between normal and CND groups.

METHODS

Ninety (95 ears) CND patients (normal cochlea, 39; malformed cochlea, 56) and seventy-nine (81 ears) normal cochlea patients who underwent CI surgery with either Med-El or Cochlear devices were included. The programming parameters and outcomes evaluated by the questionnaires were collected and compared among the normal CND, malformed CND, and normal groups in the two device groups, and their correlation was analyzed.

RESULTS

In the CND group, a reduced stimulation rate, higher pulse width, and triphasic pulse were needed in some cases. The stimulus levels of the CND group were significantly higher than that of the normal group (p < 0.05), but the outcomes of the CND group were significantly worse than that of the normal group (p < 0.05), and the stimulus level was significantly correlated with the outcomes (p < 0.05). However, there was no difference between normal and malformed CND groups. The non-auditory response was observed in the CND group, especially the ones with malformations.

CONCLUSION

The CI programming parameters of some CND patients need to be adjusted, and a slower stimulation rate and higher pulse width are required sometimes. CND patients need a higher stimulus level than normal patients but their outcomes are poorer. Non-auditory response should be noticed in CND patients during programming.

A 15-year Review of 260 Children With Auditory Neuropathy Spectrum Disorder: II. Management and Outcomes

OBJECTIVES

Following a review of the demographic and clinical characteristics of all pediatric patients diagnosed with auditory neuropathy spectrum disorder (ANSD) by a pediatric health care system from 2005 to 2020, the present report highlights the type and timing of intervention and outcomes in the same 260 patients with ANSD.

DESIGN

This was a retrospective study reviewing the demographic data, medical history, imaging studies, audiological and speech language data, type of audiological intervention (hearing aids or cochlear implants), and mode of communication in 260 pediatric patients diagnosed with ANSD over a 15-year period.

RESULTS

A significant decrease over time in the age at hearing aid fitting was observed. While a similar reduction in the age at implantation occurred over time, cochlear implantation is still rarely performed by 12 months of age in most ANSD patients. Among bilateral ANSD patients fitted with hearing aids, the majority (89.2%) did not benefit from conventional amplification and most received cochlear implants. Some hearing aid benefit for speech and language development was observed in 5.8%, though communication difficulties were persistent and most used a combination of oral and sign language for communication. Only six patients (5%) received significant benefit from their hearing aids for speech and language development.

CONCLUSIONS

This review of ANSD management over a 15-year period reveals that hearing aids are not a viable option to develop speech and language for most infants and children with ANSD. This finding confirms previous reports and suggest that while hearing aid trials are warranted, children must be tracked closely so as to avoid delays in decision making. Cochlear implantation constitutes the major (if not only) rehabilitative intervention that allows for speech perception in patients who do not benefit from conventional amplification.

Expanding Understanding of Electrocochleography in Cochlear Implantation: Auditory Neuropathy Spectrum Disorder With Normal Pure Tone Average

Objective

Describe the preoperative decision-making, intraoperative electrocochleographic (ECoG) findings, and outcome of cochlear implantation (CI) in a patient with auditory neuropathy spectrum disorder (ANSD) and normal pure-tone thresholds.

Patients

A 19-year-old with a history of hypoxic ischemic encephalopathy and seizures was referred for hearing rehabilitation in the setting of typical hearing by pure tone audiometry but poor speech understanding. A diagnosis of ANSD was made based on acoustic brainstem response (ABR), distortion product otoacoustic emission, and acoustic reflex testing. Imaging revealed no central cause of hearing impairment.

Interventions

Right-sided CI.

Main Outcome Measures

Preoperative and postoperative audiometric data. Intraoperative ECoG.

Results

Preoperatively the patient underwent comprehensive audiologic testing with behavioral audiometry, ABR testing, and CI candidacy evaluation. In the right ear, the pure tone average (PTA) was 15 dB and word recognition score was 36%. ABR confirmed ANSD. Preoperative CNC and AzBio in quiet were 8% and 0%, respectively. Intraoperative ECoG amplitudes and audiometry showed responses in the 100 uV range and estimated PTA of 42 dB HL. Postoperative testing at 1-month post-initial activation revealed PTA of 45 dB HL and unchanged word and sentence scores. However, the patient cites an improved ability to communicate and increased confidence and averages over 14 hours of device use daily.

Conclusions

To our knowledge, this is the first reported case of CI in an ear with normal PTA. Given that nearly all presently available ECoG data comes from patients with greater degrees of hearing loss, this unique case adds to our understanding of hearing preservation in CI.

Intracochlear electrocochleography findings in cochlear implant recipients with auditory neuropathy spectrum disorder

OBJECTIVES

This study aimed to compare intracochlear electrocochleography (ECochG) findings in a group of cochlear implant (CI) recipients with auditory neuropathy spectrum disorder (ANSD) with a group of CI recipients with sensorineural hearing loss (SNHL). Auditory outcome and spectral resolution findings were also compared among CI recipients with and without cochlear microphonic (CM) responses.

METHODS

This single-center, prospective cohort study was undertaken at a tertiary referral center. CM responses by the intracochlear ECochG test were recorded in CI recipients at 0.25-2 kHz. Speech, spatial, and hearing quality (SSQ) outcomes and spectral resolution measured with the spectral-temporally modulated ripple test were obtained for each recipient. The study included 62 implanted ears in 46 recipients, of which 59% (n = 27) were male and 41% (n = 19) were female. Twenty-nine ears with ANSD and 33 ears with SNHL were included. The mean age of the participants was 11 years. The results compared the intracochlear ECochG findings of the ANSD group with those of the SNHL group.

RESULTS

Participants were divided into two groups with and without obtainable CM responses. CM responses were obtained in 13 of 29 ears in the ANSD group and 14 of 33 ears in the SNHL group. CM thresholds obtained were better according to behavioral audiometric responses in some frequencies in the ANSD group. No significant difference was found in the auditory outcome and spectral resolution among CI recipients with and without CM responses.

CONCLUSIONS

Intracochlear ECochG has a limited potential clinical value for monitoring ANSD. CM thresholds obtained using ECochG may not reflect behavioral hearing thresholds.

Systematic Literature Review and Early Benefit of Cochlear Implantation in Two Pediatric Auditory Neuropathy Cases

Approximately 1 in 10 children with hearing loss is affected by auditory neuropathy spectrum disorder (ANSD). People who have ANSD usually have great difficulty understanding speech or communicating. However, it is possible for these patients to have audiograms that may indicate profound hearing loss up to normal hearing. This disorder is prognosed with positive, intact or present otoacoustic emissions (OAE) and/or cochlear microphonics (CM) as well as abnormal or absent auditory brainstem responses (ABR). Treatment methods include conventional hearing aids as well as cochlear implants. Cochlear implants (CI) usually promise better speech understanding for ANSD patients. We performed a systematic literature review aiming to show what improvements can effectively be achieved with cochlear implants in children with ANSD and compare this with our experience with two cases of ANSD implanted at our clinic. The retrospective review of two young CI patients diagnosed with ANSD during infancy demonstrated improvements over time in speech development communicated by their parents.

Short-term outcomes of infants with hyperbilirubinemia-associated auditory neuropathy spectrum disorder in neonatal intensive care unit

OBJECTIVES

Hyperbilirubinemia is a high-risk factor for auditory neuropathy spectrum disorder (ANSD) as well as hearing loss in general. This study described the outcomes of hyperbilirubinemia-associated ANSD infants diagnosed in hearing screening in the neonatal intensive care unit (NICU).

METHODS

A total of 578 children with hyperbilirubinemia admitted to the NICU between October 2020 and October 2021 were included in this study. The distortion product otoacoustic emission (DPOAE) and automatic auditory brainstem response (AABR) were combined for hearing screening, and those who failed the DPOAE or/and AABR underwent an auditory brainstem response (ABR) test. Infants with ANSD were followed up for 12 months.

RESULTS

Forty infants (40/578, 6.9%) failed the DPOAE or/and AABR tests, of which, 13 (13/578, 2.2%) were diagnosed as ANSD, and 27 (27/578, 4.7%) were diagnosed as having sensorineural hearing loss (SNHL). Of the 13 ANSD infants followed up for 12 months, 7 recovered, 3 improved, 3 did not recover, and 1 was lost, equating to improved or recovered hearing in 75% (9/12) of ANSD infants at 12 months of age. Moreover, the maximum bilirubin in recovered or improved ANSD infants was 408.6 ± 129.0 μmol/L, while the maximum bilirubin in unrecovered ANSD infants was 749.3 ± 323.0 μmol/L. Furthermore, poorly differentiated and absent ABR waveforms were observed in 6 and 14 ears at 1 month, 2 ears were lost, 6 (6/6, 100.0%) and 6 (6/12, 50.0%) ears were recovered or improved at 12 months of age.

CONCLUSION

s: The incidence of hyperbilirubinemia associated-ANSD was 2.2% of infants screened in the NICU. ANSD caused by hyperbilirubinemia may be transient, with most infants improving or recovering hearing by 12 months of age. Infants with poorly differentiated ABR waveforms and low bilirubin concentration are more likely to recover and hearing aids are not recommended in hyperbilirubinemia-associated ANSD below 12 months of age.

Auditory and Speech Outcomes of Cochlear Implantation in Children With Auditory Neuropathy Spectrum Disorder: A Systematic Review and Meta-Analysis

OBJECTIVE

The aim of this meta-analysis was to critically assess the effect of cochlear implantation on auditory and speech performance outcomes of children with auditory neuropathy spectrum disorder (ANSD).

MATERIAL AND METHODS

A systematic literature search was conducted on PubMed, EMbase, and Web of Science. The outcomes included speech recognition score, Categories of Auditory Performance (CAP), Speech Intelligibility Rating (SIR) score, and open-set speech perception. Results were expressed as standardized mean difference (SMD) or risk ratio (RR) with a 95% confidence interval (95% CI).

RESULTS

A total of 15 studies was included in this meta-analysis. Pooled data showed that, there were no significant differences between ANSD and sensorineural hearing loss (SNHL) groups in terms of speech recognition score (SMD = 0.01, 95% CI: -0.45, 0.47; P = .959),CAP (SMD = 0.71, 95% CI: -0.13, 1.54; P = .098), SIR score (SMD = -0.09, 95% CI: -0.49, 0.32; P = .667), and open-set speech perception (RR = 0.85, 95% CI: 0.69, 1.05; P = .142). Sensitivity analysis by removing individual studies one at a time showed that the overall estimate and level of heterogeneity did not change substantially.

CONCLUSION

The current evidence suggested that children with ANSD who underwent cochlear implants achieved comparable effects in auditory and speech performance as children with non-ANSD SNHL.

[Peculiarities of CI processor fitting in children with auditory neuropathy spectrum disorders]

The peculiarities of cochlear implant (CI) processor fitting in children with auditory neuropathy spectrum disorders (ANSD) were investigated. At the 1-st fitting of the CI processor a standard protocol of parameters was used in all patients, including patients with cochlear nerve hypoplasia. After the initial fitting session, the behavioral tonal thresholds with CI in 55% of patients were 30-35 dB, in 32.% of patients - 40-50 dB. After 3-6 months, 65% of children with ANSD showed significant progress in auditory-speech development, which made it possible to use the standard protocol of tuning parameters for them with the most comfortable and threshold levels of electrical stimulation adjusted according to the child's reactions. The best dynamics was observed in 2 children with presynaptic ANSD with a confirmed DFNB9 (OTOF) gene mutation. In 35% of children, there was no progress in distinguishing speech signals and instability of reactions to sounds persisted after 6 months using of CI and speech therapy training, despite the low tonal thresholds of hearing. In these children the coding strategy was changed, the stimulation frequency was reduced, and the pulse width was increased. This helped to improve the discrimination of sounds with CI and progress in the child's speech development. The results demonstrate that children with ANSD require more frequent correction of CI processor settings: 1st year - every 3 months, then at least 2 times a year until the optimal coding strategy and settings are achieved. To predict the effectiveness of CI and determine the optimal tactics for setting up the CI processor in patients with ANSD, the preoperative examination should include MRI of the cerebellopontine angle to detect anomalies of the cochlear nerve and genetic examination to identify mutations that cause hearing impairment in patients with ANSD.

Task force Guideline of Brazilian Society of Otology - hearing loss in children - Part II - Treatment

OBJECTIVES

To provide an overview of the main evidence-based recommendations for the diagnosis of hearing loss in children and adolescents aged 0-18 years.

METHODS

Task force members were educated on knowledge synthesis methods, including electronic database search, review and selection of relevant citations, and critical appraisal of selected studies. Articles written in English or Portuguese on childhood hearing loss were eligible for inclusion. The American College of Physicians' guideline grading system and the American Thyroid Association's guideline criteria were used for critical appraisal of evidence and recommendations for therapeutic interventions.

RESULTS

The topics were divided into 2 parts: (1) treatment of sensorineural hearing loss: individual hearing aids, bilateral cochlear implants, cochlear implants in young children, unilateral hearing loss, and auditory neuropathy spectrum disorder; and (2) treatment of conductive/mixed hearing loss: external/middle ear malformations, ventilation tube insertion, and tympanoplasty in children.

CONCLUSIONS

In children with hearing loss, in addition to speech therapy, Hearing AIDS (HAs) or implantable systems may be indicated. Even in children with profound hearing loss, both the use of HAs and behavioral assessments while using the device are important.

Pre-linguistic social communication skills and post implant language outcomes in deaf children with cochlear implants

PURPOSE

This study investigates the relationship between pre-linguistic social communication skills and age of cochlear implant for future language outcomes in a large sample of deaf children.

METHOD

A retrospective cohort study of records from 75 children. Pre-implant data included Age at Implant, pre-linguistic communication (social, symbolic and speech) skills, and non-verbal ability. Receptive and expressive language development data at 1 year, 2 years and 4 years post implant were analysed to investigate the relationships between pre-implant factors and language outcomes, in particular pre-linguistic social communication skills in early and late implanted children.

RESULTS

Age at Implant was the strongest correlate of post implant expressive and receptive language outcomes. The sample was divided into early implanted (<18 month) and late implanted (>18 months) children. In the early implanted group, pre-linguistic social communication skills were the strongest pre-implant correlate of language outcomes four years post-implant. In the late implanted group, there were no significant pre-implant correlates of language outcomes.

CONCLUSIONS

Long term language outcomes after cochlear implantation are the product of a set of communicative, cognitive and environmental factors. Early pre-implant social communication skills are an important consideration for clinicians who guide parents as to likely long-term outcomes post cochlear implantation. Social communication skills are particularly important for children who receive implants before the age of 18 months.

Functional Outcomes of Cochlear Implantation in Children with Bilateral Cochlear Nerve Aplasia

Background and Objectives: Many otologists face a dilemma in the decision-making process of surgical management of patients with cochlear nerve (CN) aplasia. The goal of this study is to provide fresh evidence on cochlear implantation (CI) results in patients with CN aplasia. Materials and Methods: We scrutinized functional outcomes in 37 ears of 21 children with bilateral CN aplasia who underwent unilateral or bilateral CI based on cross-sectional and longitudinal assessments. Results: The Categories of Auditory Performance (CAP) scores gradually improved throughout the 3-year follow-up; however, variable outcomes existed between individuals. Specifically, 90% of recipients with a 1-year postoperative CAP score ≤1 could not achieve a CAP score over 1 even at 3-year postoperative evaluation, while the recipients with a 1-year postoperative CAP score >1 had improved auditory performance, and 72.7% of them were able to achieve a CAP score of 4 or higher. Meanwhile, intraoperative electrically evoked compound action potential was not correlated with postoperative CAP score. Conclusions: Our results further refine previous studies on the clinical feasibility of CI as the first treatment modality to elicit favorable auditory performance in children with CN aplasia. However, special attention should be paid to pediatric patients with an early postoperative CAP score ≤1 for identification of unsuccessful cochlear implants and switching to auditory brainstem implants.

Cochlear Implantation Outcomes in Patients with Auditory Neuropathy Spectrum Disorder of Genetic and Non-Genetic Etiologies: A Multicenter Study

With diverse etiologies and clinical features, the management of pediatric auditory neuropathy spectrum disorder (ANSD) is often challenging, and the outcomes of cochlear implants (CIs) are variable. This study aimed to investigate CI outcomes in pediatric patients with ANSD of different etiologies. Thirty-six children with ANSD who underwent cochlear implantation between 2001 and 2021 were included. Comprehensive etiological analyses were conducted, including a history review, next-generation sequencing-based genetic examinations, and imaging studies using high-resolution computed tomography and magnetic resonance imaging. Serial behavioral and speech audiometry were performed before and after surgery, and the outcomes with CI were evaluated using the Categories of Auditory Performance (CAP) and Speech Intelligibility Rating (SIR) scores. By etiology, 18, 1, 1, and 10 patients had OTOF-related, WFS1-related, OPA1-related, and cochlear nerve deficiency (CND)-related ANSD, respectively. Six patients had no definite etiology. The average CI-aided behavioral threshold was 28.3 ± 7.8 dBHL, and those with CND-related ANSD were significantly worse than OTOF-related ANSD. The patients’ median CAP and SIR scores were 6 and 4, respectively. Favorable CI outcomes were observed in patients with certain etiologies of ANSD, particularly those with OTOF (CAP/SIR scores 5–7/2–5), WFS1 (CAP/SIR score 6/5), and OPA1 variants (CAP/SIR score 7/5). Patients with CND had suboptimal CI outcomes (CAP/SIR scores 2–6/1–3). Identifying the etiologies in ANSD patients is crucial before surgery and can aid in predicting prognoses.

The Feasibility of the Functional Listening Index—Paediatric (FLI-P®) for Young Children with Hearing Loss

(1) Background: There is clear evidence supporting the need for individualized early intervention in children with hearing loss. However, relying on hearing thresholds and speech and language test results to guide intervention alone is problematic, particularly in infants and young children. This study aimed to establish the feasibility of a tool to monitor the development of functional listening skills to inform early and ongoing decisions by parents and professionals. (2) Methods: The FLI-P^® is a 64-item checklist completed by parents and/or a child’s team. The listening development of 543 children with hearing loss enrolled in an early intervention and cochlear implant program was tracked with the FLI-P over a 6-year period. The scores for individual children were grouped according to hearing loss, device, additional needs, and age at device fitting. (3) Results: Results indicate that the FLI-P is a feasible and viable clinical measure that can be used to identify and track a child’s developing listening skills. Its use across a wide range of children supports its broad application. Children’s individual scores and aggregated group data were consistent with indicated expected differences and variations. Children’s individual scores and aggregated group data indicated expected differences and variations. (4) Conclusions: Information provided by children’s listening scores on the FLI-P can guide and support discussions and intervention decisions and bridge the gap between information from audiological assessments and language measures.

A Broadly Applicable Method for Characterizing the Slope of the Electrically Evoked Compound Action Potential Amplitude Growth Function

OBJECTIVES

Amplitudes of electrically evoked compound action potentials (eCAPs) as a function of the stimulation level constitute the eCAP amplitude growth function (AGF). The slope of the eCAP AGF (i.e., rate of growth of eCAP amplitude as a function of stimulation level), recorded from subjects with cochlear implants (CIs), has been widely used as an indicator of survival of cochlear nerve fibers. However, substantial variation in the approach used to calculate the slope of the eCAP AGF makes it difficult to compare results across studies. In this study, we developed an improved slope-fitting method by addressing the limitations of previously used approaches and ensuring its application for the estimation of the maximum slopes of the eCAP AGFs recorded in both animal models and human listeners with various etiologies.

DESIGN

The new eCAP AGF fitting method was designed based on sliding window linear regression. Slopes of the eCAP AGF estimated using this new fitting method were calculated and compared with those estimated using four other fitting methods reported in the literature. These four methods were nonlinear regression with a sigmoid function, linear regression, gradient calculation, and boxcar smoothing. The comparison was based on the fitting results of 72 eCAP AGFs recorded from 18 acutely implanted guinea pigs, 46 eCAP AGFs recorded from 23 chronically implanted guinea pigs, and 2094 eCAP AGFs recorded from 200 human CI users from 4 patient populations. The effect of the choice of input units of the eCAP AGF (linear versus logarithmic) on fitting results was also evaluated.

RESULTS

The slope of the eCAP AGF was significantly influenced by the slope-fitting method and by the choice of input units. Overall, slopes estimated using all five fitting methods reflected known patterns of neural survival in human patient populations and were significantly correlated with speech perception scores. However, slopes estimated using the newly developed method showed the highest correlation with spiral ganglion neuron density among all five fitting methods for animal models. In addition, this new method could reliably and accurately estimate the slope for 4 human patient populations, while the performance of the other methods was highly influenced by the morphology of the eCAP AGF.

CONCLUSIONS

The novel slope-fitting method presented in this study addressed the limitations of the other methods reported in the literature and successfully characterized the slope of the eCAP AGF for various animal models and CI patient populations. This method may be useful for researchers in conducting scientific studies and for clinicians in providing clinical care for CI users.

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.

Prevalence, risk factors, and audiological characteristics of auditory neuropathy

OBJECTIVE

The objective of this study was to determine the prevalence, risk factors, and audiological characteristics of auditory neuropathy spectrum disorder (ANSD) in the pediatric population.

DESIGN

A retrospective review of medical charts was conducted for children visiting two hospitals in Saudi Arabia.

STUDY SAMPLE

Medical records of 1025 patients with sensorineural hearing loss (SNHL) were reviewed. We analyzed the databases for results of audiological examinations, risk factors, and outcomes of intervention including hearing aid (HA) and cochlear implantation (CI).

RESULTS

Out of 1025 children with SNHL, 101 patients (9.85%) were identified to have ANSD. Audiological characteristics of the ANSD group revealed a severe-to-profound degree of hearing loss, all showed type A tympanogram and absent reflexes, absent auditory brainstem response (ABR) findings with present cochlear microphonic while otoacoustic emissions were absent in 54.5% of patients. The most prevalent risk factors for ANSD in this group were family history of hearing loss, consanguinity, hyperbilirubinemia, and low birth weight. Pure tone and speech detection thresholds improved significantly with CI compared to HA use in this sample of patients with ANSD.

CONCLUSION

This study shows that ANSD is not extremely rare among Saudi children with severe to profound hearing loss, with a prevalence of 9.85%.

Perception of temporally enhanced and hearing aid processed speech in children with late-onset Auditory Neuropathy Spectrum Disorder

OBJECTIVE

To investigate phrase perception and subjective quality preference of temporal enhancement-based speech processing strategies: Deep-band modulation and Stretching, and hearing aid processed speech in adolescents with late-onset Auditory Neuropathy.

METHODS

15 participants with Auditory Neuropathy Spectrum Disorder were involved. Speech perception was assessed using unprocessed, deep-band modulated, stretched, and hearing aid processed conditions. Subjective preference was also assessed using the pair-wise comparison technique. Gap detection test was done using broadband noise to investigate the possible correlation with benefit from processing strategies.

RESULTS

As a group, no significant benefits were found with processed speech. Clinically relevant trends emerged on subdividing the group into good and poor performers. Deep-band modulation processing was significantly better than unprocessed speech in those with poorer speech recognition abilities. There was a trend for those with poorer temporal processing abilities to benefit more with deep-band modulation processing. In those with relatively better speech recognition abilities, processing showed no benefit, and hearing aid processed speech was inferior to unprocessed speech. Quality-wise, the unprocessed speech was preferred by all the participants. Among the processed conditions, deep-band modulation was preferred by most, followed by stretching and hearing aid processed speech.

CONCLUSION

Results indicate that temporal enhancement strategies may be beneficial for a subset of individuals with ANSD with poorer temporal processing and speech perception abilities. However, processing strategies need to take into account the quality aspect and not just intelligibility.

Auditory testing outcomes with hearing aids in patients with auditory neuropathy spectrum disorder

OBJECTIVE

The objective of this study is to evaluate the audiologic outcomes with hearing aids in pediatric patients with auditory neuropathy spectrum disorder (ANSD) using the Infant Toddler-Meaningful Auditory Integration Scale (IT-MAIS), and the Ling 6 Sound Test (Ling 6).

STUDY DESIGN

Case series.

SETTING

Single tertiary care academic medical center.

SUBJECTS AND METHODS

All pediatric patients with a confirmed diagnosis of ANSD on Auditory Brainstem Response (ABR) testing who presented to a single tertiary medical center between September 2008 and September 2018 were included. Only patients that underwent Infant Toddler-Meaningful Auditory Integration Scale (IT-MAIS) and/or Ling 6 Sound Test (Ling 6) were included in the study. Audiologic testing performed after cochlear implantation was excluded.

RESULTS

60 pediatric patients with ANSD were analyzed. There were 10 patients included in the study with documented hearing aid use who underwent IT-MAIS and/or Ling 6 testing. Average IT-MAIS score improved by 20.4% after initial or extended trial of amplification. Similarly, average Ling 6 score improved from 3.6 to 4.8 after initial or extended trial of amplification. The four patients who did not receive amplification had higher average IT-MAIS and Ling 6 scores.

CONCLUSION

In most children with ANSD, IT-MAIS and Ling 6 Sound Test scores improved with initial hearing aid use and over time with extended hearing aid use. Long-term prospective, multi-institutional studies are needed to determine the impact of the natural history of ANSD, comorbidities, and socioeconomic variables on auditory function testing results in children with ANSD using hearing aids.

The natural history of OTOF-related auditory neuropathy spectrum disorders: a multicenter study

Pathogenic variations in the OTOF gene are a common cause of hearing loss. To refine the natural history and genotype-phenotype correlations of OTOF-related auditory neuropathy spectrum disorders (ANSD), audiograms and distortion product otoacoustic emissions (DPOAEs) were collected from a diverse cohort of individuals diagnosed with OTOF-related ANSD by comprehensive genetic testing and also reported in the literature. Comparative analysis was undertaken to define genotype-phenotype relationships using a Monte Carlo algorithm. 67 audiograms and 25 DPOAEs from 49 unique individuals positive for OTOF-related ANSD were collected. 51 unique OTOF pathogenic variants were identified of which 21 were missense and 30 were loss of function (LoF; nonsense, splice-site, copy number variants, and indels). There was a statistically significant difference in low, middle, and high frequency hearing thresholds between missense/missense and LoF/missense genotypes as compared to LoF/LoF genotypes (average hearing threshold for low, middle and high frequencies 70.9, 76.0, and 73.4 dB vs 88.5, 95.6, and 94.7 dB) via Tukey's test with age as a co-variate (P = 0.0180, 0.0327, and 0.0347, respectively). Hearing declined during adolescence with missense/missense and LoF/missense genotypes, with an annual mid-frequency threshold deterioration of 0.87 dB/year and 1.87 dB/year, respectively. 8.5% of frequencies measured via DPOAE were lost per year in individuals with serial tests. Audioprofiling of OTOF-related ANSD suggests significantly worse hearing with LoF/LoF genotypes. The unique pattern of variably progressive OTOF-related autosomal recessive ANSD may be amenable to gene therapy in selected clinical scenarios.

Effect of Increasing Pulse Phase Duration on Neural Responsiveness of the Electrically Stimulated Cochlear Nerve

OBJECTIVES

The aim of this study is to (1) investigate the effects of increasing the pulse phase duration (PPD) on the neural response of the electrically stimulated cochlear nerve (CN) in children with CN deficiency (CND) and (2) compare the results from the CND population to those measured in children with normal-sized CNs.

DESIGN

Study participants included 30 children with CND and 30 children with normal-sized CNs. All participants used a Cochlear Nucleus device in the test ear. For each subject, electrically evoked compound action potential (eCAP) input/output (I/O) functions evoked by single biphasic pulses with different PPDs were recorded at three electrode locations across the electrode array. PPD durations tested in this study included 50, 62, 75, and 88 μsec/phase. For each electrode tested for each study participant, the amount of electrical charge corresponding to the maximum comfortable level measured for the 88 μsec PPD was used as the upper limit of stimulation. The eCAP amplitude measured at the highest electrical charge level, the eCAP threshold (i.e., the lowest level that evoked an eCAP), and the slope of the eCAP I/O function were measured. Generalized linear mixed effect models with study group, electrode location, and PPD as the fixed effects and subject as the random effect were used to compare these dependent variables measured at different electrode locations and PPDs between children with CND and children with normal-sized CNs.

RESULTS

Children with CND had smaller eCAP amplitudes, higher eCAP thresholds, and smaller slopes of the eCAP I/O function than children with normal-sized CNs. Children with CND who had fewer electrodes with a measurable eCAP showed smaller eCAP amplitudes and flatter eCAP I/O functions than children with CND who had more electrodes with eCAPs. Increasing the PPD did not show a statistically significant effect on any of these three eCAP parameters in the two subject groups tested in this study.

CONCLUSIONS

For the same amount of electrical charge, increasing the PPD from 50 to 88 μsec for a biphasic pulse with a 7 μsec interphase gap did not significantly affect CN responsiveness to electrical stimulation in human cochlear implant users. Further studies with different electrical pulse configurations are warranted to determine whether evaluating the eCAP sensitivity to changes in the PPD can be used as a testing paradigm to estimate neural survival of the CN for individual cochlear implant users.

Amplitude Growth Functions of Auditory Nerve Responses to Electric Pulse Stimulation With Varied Interphase Gaps in Cochlear Implant Users With Ipsilateral Residual Hearing

Amplitude growth functions (AGFs) of electrically evoked compound action potentials (eCAPs) with varying interphase gaps (IPGs) were measured in cochlear implant users with ipsilateral residual hearing (electric-acoustic stimulation [EAS]). It was hypothesized that IPG effects on AGFs provide an objective measure to estimate neural health. This hypothesis was tested in EAS users, as residual low-frequency hearing might imply survival of hair cells and hence better neural health in apical compared to basal cochlear regions. A total of 16 MED-EL EAS subjects participated, as well as a control group of 16 deaf cochlear implant users. The IPG effect on the AGF characteristics of slope, threshold, dynamic range, and stimulus level at 50% maximum eCAP amplitude (level_50%) was investigated. AGF threshold and level_50% were significantly affected by the IPG in both EAS and control group. The magnitude of AGF characteristics correlated with electrode impedance and electrode-modiolus distance (EMD) in both groups. In contrast, the change of the AGF characteristics with increasing IPG was independent of these electrode-specific measures. The IPG effect on the AGF level_50% in both groups, as well as on the threshold in EAS users, correlated with the duration of hearing loss, which is a predictor of neural health. In EAS users, a significantly different IPG effect on level_50% was found between apical and medial electrodes. This outcome is consistent with our hypothesis that the influence of IPG effects on AGF characteristics provides a sensitive measurement and may indicate better neural health in the apex compared to the medial cochlear region in EAS users.

Recommendations for Measuring the Electrically Evoked Compound Action Potential in Children With Cochlear Nerve Deficiency

OBJECTIVES

This study reports a method for measuring the electrically evoked compound action potential (eCAP) in children with cochlear nerve deficiency (CND).

DESIGN

This method was developed based on experience with 50 children with CND who were Cochlear Nucleus cochlear implant users.

RESULTS

This method includes three recommended steps conducted with recommended stimulating and recording parameters: initial screen, pulse phase duration optimization, and eCAP threshold determination (i.e., identifying the lowest stimulation level that can evoke an eCAP). Compared with the manufacturer-default parameters, the recommended parameters used in this method yielded a higher success rate for measuring the eCAP in children with CND.

CONCLUSIONS

The eCAP can be measured successfully in children with CND using recommended parameters. This specific method is suitable for measuring the eCAP in children with CND in clinical settings. However, it is not suitable for intraoperative eCAP recordings due to the extensive testing time required.

X-linked Malformation Deafness: Neurodevelopmental Symptoms Are Common in Children With IP3 Malformation and Mutation in POU3F4

Supplemental Digital Content is available in the text.

Incomplete partition type 3 (IP3) malformation deafness is a rare hereditary cause of congenital or rapid progressive hearing loss. The children present with a severe to profound mixed hearing loss and temporal bone imaging show a typical inner ear malformation classified as IP3. Cochlear implantation is one option of hearing restoration in severe cases. Little is known about other specific difficulties these children might exhibit, for instance possible neurodevelopmental symptoms.

Central auditory maturation and behavioral outcomes after cochlear implantation in prelingual auditory neuropathy spectrum disorder related to OTOF variants (DFNB9): Lessons from pilot study

The cortical auditory evoked potential (CAEP)-based P1 component acts as a biomarker for cochlear implantation (CI) outcomes in children with auditory neuropathy spectrum disorder (ANSD). To date, early intervention primarily before the age of two years and six months of CI usage is necessary and sufficient to achieve age-appropriate cortical maturation and good prognosis. However, varying degrees of neural dyssynchrony, resulting from the etiological heterogeneity of ANSD, may preclude uniform application of this hypothesis to ensure auditory cortical maturation. Thus, a focused evaluation of those carrying OTOF variants, which may be the salient molecular etiology of prelingual ANSD, would circumvent the issue of heterogeneity. Here, we sought to provide a much better understanding of the brain perspectives (i.e., P1 maturation) in OTOF-associated ANSD subjects and set the stage for an optimal strategy to enhance language development. We conducted a preliminary study comprising 10 subjects diagnosed with OTOF-related ANSD who underwent CI by a single surgeon and subsequently underwent measurements of the P1 component. We observed that DFNB9 subjects who received CI after 2 years of age exhibited “absent” or “anomalous” P1 components that correspond to delayed language development. However, timely implantation, as early as 12 months of age per se, might be insufficient to achieve age-appropriate cortical maturation of DFNB9 in cases with six to seven months of device use. This suggests the importance of sustained rehabilitation in DFNB9 than in other etiologies. Indeed, an additional follow-up study showed that a reduction in P1 latency was linked to an improvement in auditory performance. Collectively, our results suggest that central auditory maturation and successful outcome of CI in DFNB9 may have more demanding requirements, that is, earlier implantation and more sustained rehabilitation. We believe that the current study opens a new path toward genome-based neuroimaging in the field of hearing research.

Effect of Quiet and Noise on P300 Response in Individuals with Auditory Neuropathy Spectrum Disorder

Introduction  Auditory neuropathy spectrum disorder (ANSD) is a clinical condition in which individuals have normal cochlear responses and abnormal neural responses. There is a lack of evidence in the literature regarding the neural discrimination skill in individuals with ANSD, especially when the signal is presented in the presence of noise. Objectives  The present study was performed with the aim to investigate auditory discrimination skill, in quiet and in the presence of noise, in individuals with ANSD and to compare the findings with normal-hearing individuals. Methods  A total of 30 individuals with normal hearing sensitivity and 30 individuals with ANSD in the age range of 15 to 55 years old, with the mean age of 27.86 years old, were the participants. P300 response was recorded from both groups using syllable pairs /ba/-/da/ in oddball paradigm and the syllable /da/ in repetitive paradigm in quiet and at +10 dB signal-to-noise ratio (SNR). Results  There was significant prolongation in latency and reaction time, and reduction in amplitude of P300 response and sensitivity in both groups with the addition of noise. The topographic pattern analysis showed activation of the central-parietal-occipital region of the brain in individuals with ANSD, whereas activation of the central-parietal region was observed in individuals with normal hearing. The activation was more diffused in individuals with ANSD compared with that of individuals with normal hearing. Conclusion  The individuals with ANSD showed a significantly more adverse effect of noise on the neural discrimination skill than the normal counterpart.

Prediction of the Functional Status of the Cochlear Nerve in Individual Cochlear Implant Users Using Machine Learning and Electrophysiological Measures

OBJECTIVES

This study aimed to create an objective predictive model for assessing the functional status of the cochlear nerve (CN) in individual cochlear implant (CI) users.

DESIGN

Study participants included 23 children with cochlear nerve deficiency (CND), 29 children with normal-sized CNs (NSCNs), and 20 adults with various etiologies of hearing loss. Eight participants were bilateral CI users and were tested in both ears. As a result, a total of 80 ears were tested in this study. All participants used Cochlear Nucleus CIs in their test ears. For each participant, the CN refractory recovery function and input/output (I/O) function were measured using electrophysiological measures of the electrically evoked compound action potential (eCAP) at three electrode sites across the electrode array. Refractory recovery time constants were estimated using statistical modeling with an exponential decay function. Slopes of I/O functions were estimated using linear regression. The eCAP parameters used as input variables in the predictive model were absolute refractory recovery time estimated based on the refractory recovery function, eCAP threshold, slope of the eCAP I/O function, and negative-peak (i.e., N1) latency. The output variable of the predictive model was CN index, an indicator for the functional status of the CN. Predictive models were created by performing linear regression, support vector machine regression, and logistic regression with eCAP parameters from children with CND and the children with NSCNs. One-way analysis of variance with post hoc analysis with Tukey's honest significant difference criterion was used to compare study variables among study groups.

RESULTS

All three machine learning algorithms created two distinct distributions of CN indices for children with CND and children with NSCNs. Variations in CN index when calculated using different machine learning techniques were observed for adult CI users. Regardless of these variations, CN indices calculated using all three techniques in adult CI users were significantly correlated with Consonant-Nucleus-Consonant word and AzBio sentence scores measured in quiet. The five oldest CI users had smaller CN indices than the five youngest CI users in this study.

CONCLUSIONS

The functional status of the CN for individual CI users was estimated by our newly developed analytical models. Model predictions of CN function for individual adult CI users were positively and significantly correlated with speech perception performance. The models presented in this study may be useful for understanding and/or predicting CI outcomes for individual patients.

Therapeutic challenges and clinical characteristics of single-sided deafness in children

INTRODUCTION

The clinical implications of single-sided deafness (SSD) in children has historically been underappreciated by patients and providers alike, despite a large body of literature on the wide-ranging neurocognitive, language, scholastic, and functional impairments that occur. Conventional amplification options are marked by variable results and frequent loss of follow-up.

METHODS

Retrospective case series for pediatric SSD from 2008 to 2018.

RESULTS

88 children with congenital SSD were identified. Seventeen (N = 17/88, 23.9%) passed their newborn hearing screen. Median age at first otolaryngology evaluation was 0.65 years (range 0.1-16.9 years). Most common etiologies included cochlear nerve deficiency (N = 39, CND, 44.3%), unknown (N = 30, 35.2%), inner ear malformation (N = 7, 8.0%), and congenital cytomegalovirus (N = 6, 6.8%). 32.5% of patients elected for continued observation only, followed by bone conduction hearing aid (27.7%), contralateral routing of sound aid (20.5%), conventional hearing aid (13.3%), or cochlear implant (6%). Lack of follow-up at ≥1 year was common (39.8%). Of those with device use data (N = 39), 84.7% reported either discontinued or <6 h of daily use.

CONCLUSIONS

Despite early diagnosis and evaluation, the pediatric SSD cohort is characterized by high rates of loss of follow-up and amplification discontinuation. Cochlear nerve deficiency is commonly seen in congenital SSD. Early specialist referral is critical for habilitation evaluation. Patients and caregivers should be educated on the significant implications of unilateral hearing loss.

Identification of Perinatal Risk Factors for Auditory Neuropathy Spectrum Disorder

OBJECTIVES/HYPOTHESIS

To identify medical risk factors associated with auditory neuropathy spectrum disorder (ANSD).

STUDY DESIGN

Retrospective case-control study.

METHODS

During a 2-year period (2013-2014) patients with newly diagnosed ANSD were identified at a tertiary care facility. Twenty-two patients (n = 22) were identified aged 0.5 to 8.1 years. There were 15 males and seven females. Sixteen had bilateral, four had left-sided, and two had right-sided ANSD. Two age-matched, side-matched, and gender-matched control groups were then collected. The first group was 22 normal-hearing children (n = 22). The second was 22 children with sensorineural hearing loss (SNHL) (n = 22) who did not meet the criteria for ANSD. The chart of each subject was reviewed for the following five-predictor variables: prematurity, low birth weight, jaundice, use of mechanical ventilation, and administration of ototoxic medications. Analysis of variance was performed to analyze the prevalence of perinatal risk factors among the three groups. Multivariate linear regression was then applied.

RESULTS

When comparing the ANSD group to both the normal-hearing and SNHL groups, the subjects with ANSD had statistically significant higher rates of prematurity, low birth weight, jaundice, and mechanical ventilation. Multiple regression analysis was performed to identify predictors of ANSD compared to each control group individually. Jaundice in the first month of life approached significance when comparing the ANSD group to the normal-hearing group, and was the only medical risk factor found to be statistically significant when comparing the ANSD group to the SNHL group.

CONCLUSIONS

A history of neonatal hyperbilirubinemia was significantly more common in children with ANSD compared to children with severe SNHL.

LEVEL OF EVIDENCE

3 Laryngoscope, 131:671-674, 2021.

Cortical Auditory Event-Related Potentials and Categorical Perception of Voice Onset Time in Children With an Auditory Neuropathy Spectrum Disorder

Objective: This study evaluated cortical encoding of voice onset time (VOT) in quiet and noise, and their potential associations with the behavioral categorical perception of VOT in children with auditory neuropathy spectrum disorder (ANSD). Design: Subjects were 11 children with ANSD ranging in age between 6.4 and 16.2 years. The stimulus was an /aba/-/apa/ vowel-consonant-vowel continuum comprising eight tokens with VOTs ranging from 0 ms (voiced endpoint) to 88 ms (voiceless endpoint). For speech in noise, speech tokens were mixed with the speech-shaped noise from the Hearing In Noise Test at a signal-to-noise ratio (SNR) of +5 dB. Speech-evoked auditory event-related potentials (ERPs) and behavioral categorization perception of VOT were measured in quiet in all subjects, and at an SNR of +5 dB in seven subjects. The stimuli were presented at 35 dB SL (re: pure tone average) or 115 dB SPL if this limit was less than 35 dB SL. In addition to the onset response, the auditory change complex (ACC) elicited by VOT was recorded in eight subjects. Results: Speech evoked ERPs recorded in all subjects consisted of a vertex positive peak (i.e., P1), followed by a trough occurring approximately 100 ms later (i.e., N2). For results measured in quiet, there was no significant difference in categorical boundaries estimated using ERP measures and behavioral procedures. Categorical boundaries estimated in quiet using both ERP and behavioral measures closely correlated with the most-recently measured Phonetically Balanced Kindergarten (PBK) scores. Adding a competing background noise did not affect categorical boundaries estimated using either behavioral or ERP procedures in three subjects. For the other four subjects, categorical boundaries estimated in noise using behavioral measures were prolonged. However, adding background noise only increased categorical boundaries measured using ERPs in three out of these four subjects. Conclusions: VCV continuum can be used to evaluate behavioral identification and the neural encoding of VOT in children with ANSD. In quiet, categorical boundaries of VOT estimated using behavioral measures and ERP recordings are closely associated with speech recognition performance in children with ANSD. Underlying mechanisms for excessive speech perception deficits in noise may vary for individual patients with ANSD.

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

INTRODUCTION

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

METHODS

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

RESULTS

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

CONCLUSIONS

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

Auditory Neuropathy Spectrum Disorders: From Diagnosis to Treatment: Literature Review and Case Reports

Auditory neuropathy spectrum disorder (ANSD) refers to a range of hearing impairments characterized by deteriorated speech perception, despite relatively preserved pure-tone detection thresholds. Affected individuals usually present with abnormal auditory brainstem responses (ABRs), but normal otoacoustic emissions (OAEs). These electrophysiological characteristics have led to the hypothesis that ANSD may be caused by various dysfunctions at the cochlear inner hair cell (IHC) and spiral ganglion neuron (SGN) levels, while the activity of outer hair cells (OHCs) is preserved, resulting in discrepancies between pure-tone and speech comprehension thresholds. The exact prevalence of ANSD remains unknown; clinical findings show a large variability among subjects with hearing impairment ranging from mild to profound hearing loss. A wide range of prenatal and postnatal etiologies have been proposed. The study of genetics and of the implicated sites of lesion correlated with clinical findings have also led to a better understanding of the molecular mechanisms underlying the various forms of ANSD, and may guide clinicians in better screening, assessment and treatment of ANSD patients. Besides OAEs and ABRs, audiological assessment includes stapedial reflex measurements, supraliminal psychoacoustic tests, electrocochleography (ECochG), auditory steady-state responses (ASSRs) and cortical auditory evoked potentials (CAEPs). Hearing aids are indicated in the treatment of ANSD with mild to moderate hearing loss, whereas cochlear implantation is the first choice of treatment in case of profound hearing loss, especially in case of IHC presynaptic disorders, or in case of poor auditory outcomes with conventional hearing aids.

Music and psychoacoustic perception abilities in cochlear implant users with auditory neuropathy spectrum disorder

OBJECTIVE

Auditory neuropathy spectrum disorder (ANSD) is a condition wherein the pre-neural or cochlear outer hair cell activity is intact, but the neural activity in the auditory nerve is disrupted. Cochlear implant (CI) can be beneficial for subjects with ANSD; however, little is known about the music perception and psychoacoustic abilities of CI users with ANSD. Music perception in CI users is a multidimensional and complex ability requiring the contribution of both auditory and nonauditory abilities. Even though auditory abilities lay the foundation, the contribution of patient-related variables such as ANSD may affect the music perception. This study aimed to evaluate the psychoacoustic and music perception abilities of CI recipients with ANSD.

STUDY DESIGN

Twelve CI users with ANSD and twelve age- and gendermatched CI users with sensorineural hearing loss (SNHL) were evaluated. Music perception abilities were measured using the Turkish version of the Clinical Assessment of Music Perception (T-CAMP) test. Psychoacoustic abilities were measured using the spectral ripple discrimination (SRD) and temporal modulation transfer function (TMTF) tests. In addition, the age of diagnosis and implantation was recorded.

RESULTS

Pitch direction discrimination (PDD), timbre recognition, SRD, and TMTF performance of CI users with ANSD were concordant with those reported in previous studies, and differences between ANSD and SNHL groups were not statistically significant. However, the ANSD group performed poorly compared with SNHL group in melody recognition subtest of T-CAMP, and the difference was statistically significant.

CONCLUSION

CI can prove beneficial for patients with ANSD with respect to their music and psychoacoustic abilities, similar to patients with SNHL, except for melody recognition. Recognition of melodies requires both auditory and non-auditory abilities, and ANSD may have an extensive but subtle effect in the life of CI users.

Cochlear Implant Performance in Adult Patients with Absent Intraoperative Electrically Evoked Compound Action Potentials

OBJECTIVE

To describe cochlear implant performance outcomes in adult patients in whom no intraoperative electrically evoked compound action potential (ECAP) responses were able to be obtained despite intracochlear electrode placement.

STUDY DESIGN

Retrospective case review.

SETTING

Academic tertiary center.

SUBJECTS AND METHODS

Patients 18 years of age and older undergoing cochlear implantation between May 2010 and September 2018 with absent ECAP measurements intraoperatively with intracochlear electrode positioning were identified. Patient performance on sentence recognition testing using the Hearing in Noise Test (HINT) and AzBio at 6 to 12 months postoperatively was compared to preimplantation scores. Additional collected data included patient demographics, etiology of hearing loss, and preoperative pure-tone average (PTA) and word recognition scores (WRSs).

RESULTS

Intraoperative ECAP measurements were unable to be obtained in 15 cochlear implants performed on 14 patients out of 383 cochlear implant cases. Of the patients with absent ECAP measures, the mean ± SD age was 61.7 ± 15.7 years. Causes of hearing loss included congenital hearing loss, meningitis, autoimmune inner ear disease, otosclerosis, presbycusis, and Ménière's disease. The average preoperative PTA was 103.5 ± 17.0 dB. Twelve implanted ears had a WRS of 0% and 9 had a HINT score of 0% prior to surgery. The mean HINT score at 6 to 12 months postimplantation was 57.8% ± 37.8% and had improved by 42.6% ± 35.6% compared to the mean preimplantation HINT score (95% confidence interval, 22.0%-63.1%, P = .001, paired Student t test).

CONCLUSION

There is a wide range of cochlear implant performance in patients with absent intraoperative ECAP measures ranging from sound awareness to HINT scores of 100%.

Residual Cochlear Function in Adults and Children Receiving Cochlear Implants: Correlations With Speech Perception Outcomes

OBJECTIVES

Variability in speech perception outcomes with cochlear implants remains largely unexplained. Recently, electrocochleography, or measurements of cochlear potentials in response to sound, has been used to assess residual cochlear function at the time of implantation. Our objective was to characterize the potentials recorded preimplantation in subjects of all ages, and evaluate the relationship between the responses, including a subjective estimate of neural activity, and speech perception outcomes.

DESIGN

Electrocochleography was recorded in a prospective cohort of 284 candidates for cochlear implant at University of North Carolina (10 months to 88 years of ages). Measurement of residual cochlear function called the "total response" (TR), which is the sum of magnitudes of spectral components in response to tones of different stimulus frequencies, was obtained for each subject. The TR was then related to results on age-appropriate monosyllabic word score tests presented in quiet. In addition to the TR, the electrocochleography results were also assessed for neural activity in the forms of the compound action potential and auditory nerve neurophonic.

RESULTS

The TR magnitude ranged from a barely detectable response of about 0.02 µV to more than 100 µV. In adults (18 to 79 years old), the TR accounted for 46% of variability in speech perception outcome by linear regression (r = 0.46; p < 0.001). In children between 6 and 17 years old, the variability accounted for was 36% (p < 0.001). In younger children, the TR accounted for less of the variability, 15% (p = 0.012). Subjects over 80 years old tended to perform worse for a given TR than younger adults at the 6-month testing interval. The subjectively assessed neural activity did not increase the information compared with the TR alone, which is primarily composed of the cochlear microphonic produced by hair cells.

CONCLUSIONS

The status of the auditory periphery, particularly of hair cells rather than neural activity, accounts for a large fraction of variability in speech perception outcomes in adults and older children. In younger children, the relationship is weaker, and the elderly differ from other adults. This simple measurement can be applied with high throughput so that peripheral status can be assessed to help manage patient expectations, create individually-tailored treatment plans, and identify subjects performing below expectations based on residual cochlear function.

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

OBJECTIVES

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

METHODS

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

RESULTS

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

CONCLUSION

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

Parents' View on Quality of Life after Cochlear Implantation in Children with Auditory Neuropathy

OBJECTIVES

The aim of this study is to evaluate the quality of life in pediatric patients with auditory neuropathy according to the perspective of their parents after cochlear implantation.

MATERIALS AND METHODS

The pediatric patients, who underwent cochlear implantation with the diagnosis of auditory neuropathy at İzmir Bozyaka Training and Research Hospital ENT Clinic between January 1997 and May 2017, were included to the study. "Parents' Perspective Questionnaire" developed by Nottingham Pediatric Cochlear Implant Programme was used in the study. The questionnaire was composed of 11 subscales and 58 questions in total.

RESULTS

The study included 26 pediatric patients (14 female, 12 male) who used cochlear implant for at least 1 year. The mean age of patients was 10.91±3.85 ( 4.3-17.3 years old) and implantation age varied between 14 months and 80 months. (median; 35.65±20.03 months). Patients who attended school had more self-confidence, and also those having implant use over 6 years had a better self confidence and social relationship.

CONCLUSION

Cochlear implantation not only improves the ability of hearing but also provides development of speech and language skills and therefore enhancing the patient's quality of life. From the perspective of parents, the use of cochlear implant in the children with auditory neuropathy improves the quality of life in many different ways. The perspective of parents can provide a multidimensional evaluation about the child's progress, therefore, ıt should be taken into consideration by the staff in implant centers.

Cochlear Implantation in a Case of Auditory Neuropathy Spectrum Disorder with CAPOS Syndrome

Auditory neuropathy spectrum disorder (ANSD) is a hearing disorder which characterized with normal outer hair cell function but disrupted neural synchrony in the afferent auditory pathway. CAPOS (cerebellar ataxia, areflexia, pes cavus, optic atrophy, and sensorineural hearing loss) syndrome can manifest itself with ANSD and this rare situation and audiological rehabilitation outcomes have not well documented in the literature. We aim to present a cochlear implant user subject with CAPOS syndrome and ANSD. A 14-year-old girl diagnosed with ANSD and CAPOS syndrome. She received unilateral cochlear implant (CI). Her hearing sensitivity and speech perception abilities have been improved with CI. Also, she has a good music perception ability measured with the Turkish version of Clinical Assessment of Music Perception Test. After detailed audiological evaluations, CI could be a good option for patients who have ANSD and CAPOS syndrome.