Auditory Neuropathy Spectrum Disorder Patients Research Articles

Audiogram Configuration, Molecular Etiology, and Outcome of Cochlear Implantation in Postlingual Auditory Neuropathy Spectrum Disorder.

To explore the diverse molecular etiologies of postlingual auditory neuropathy spectrum disorder (ANSD) and report on the electrically evoked compound action potential (ECAP) thresholds and the outcome of cochlear implantation (CI). Patients with late-onset, progressive hearing loss who went through molecular genetic testing were enrolled. Type of sensorineural hearing loss (SNHL) was classified as flat, reverse-slope, midfrequency, downsloping, or ski slope. We identified postlingual ANSD subjects through diagnostic tracts applied differently depending on the degree of SNHL. For CI recipients, individual ECAP thresholds, postoperative speech perception abilities, and the genetic cause were analyzed. The detection rate of ANSD among patients with postlingual SNHL was 5.1% (15/293 probands). Diverse genetic etiologies were identified in 7 (46.6%) of the 15 postlingual ANSD subjects, the genetic cause being found exclusively in subjects with reverse-slope SNHL. The pattern of intraoperative ECAP responses was also diverse and showed some correlation with the genetic etiology. Despite the diverse molecular etiology and ECAP responses, CI in postlingual ANSD patients, including those with features involving the postsynaptic component, yielded significant improvements in speech understanding. This study proposes a differentiated diagnostic approach that focuses on both poor speech discrimination and reverse-slope hearing loss for the diagnosis of ANSD. Based on the improvement of speech understanding from all cochlear implantees with ANSD as well as the correlation between the genetic etiology and ECAP thresholds, we suggest that CI can significantly benefit ANSD subjects even those with unknown etiologies unless there is overt peripheral neuropathy.

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

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. 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. 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. 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.

Speech and Language outcomes in Auditory Neuropathy Spectrum Disorder (ANSD) children managed with amplification

ObjectiveTo evaluate speech and language outcomes in children with Auditory Neuropathy Spectrum Disorder (ANSD) without significant comorbidities who received hearing rehabilitation in the form of hearing aids and/or cochlear implantation. MethodsRetrospective chart review of pediatric ANSD patients at a large academic tertiary care institution from 2010 to 2019. Patients were included if they received a diagnosis of bilateral ANSD, had minimal to no comorbidities, and had speech and language testing (SLT) on at least two occasions. Results51 patients were reviewed and 7 met inclusion criteria. Average age at ANSD diagnosis was 1 year and 11 months, and average age of hearing aid fitting was 3 years and 3 months. Hearing loss ranged from mild to profound, with four of the children wearing behind (BTE) hearing aids and three eventually receiving cochlear implants. Four of five patients who received hearing aids prior to their first speech and language evaluation demonstrated a delay at their initial evaluation, and all five patients continued to demonstrate a delay at their most recent evaluation, despite appropriate audiologic management and speech and language therapy. There were two patients who were unaided at the time of their initial and latest evaluations; one patient showed a delay at both timepoints, and one patient showed no speech delay at either timepoint. ConclusionsPediatric ANSD patients, who are otherwise typically developing and received hearing rehabilitation and speech and language therapy, continue to show a speech and language delay (SLD). This outcome underscores the importance of close monitoring of speech and language development, providing early amplification and/or cochlear implantation, and promoting additional education and psychosocial support.

Profiles and predictors of onset based differences in vocal characteristics of adults with auditory neuropathy spectrum disorder (ANSD)

PurposeOnset-based differences are understudied in Auditory Neuropathy Spectrum Disorder (ANSD) in dimensions such as voice, which is addressed in the study. The study aimed to profile and predict the best metrics of onset-related differences in acoustic vocal characteristics of early and late-onset ANSD patients. Methods31 participants (15 early and 16 late-onset) aged 15–30 years diagnosed with ANSD were included in the study. The sustained phonation of vowel /i/ recorded by the participants using android based smartphones of selected configuration was sent over email to the experimenter. Acoustic parameters (fundamental frequency, harmonic frequencies, jitter, shimmer, harmonic-to-noise ratio, cepstral peak prominence -CPP, and pitch sigma) were analysed using Praat software. ResultsResults revealed significantly increased (p < 0.05) fundamental frequency along with decreased F2 and F3 of /i/ in the early-onset ANSD compared to the late-onset group, which can be explained based on differences in the pathophysiology of the disorder. Although not statistically significant, mean perturbations (jitter and shimmer), harmonic-to-noise ratio, cepstral peak prominence, and pitch sigma were more affected in the early-onset group, reflective of lowered auditory feedback and periodicity in their voice samples. Results of discriminant analysis marked the emergence of F2, F3, and CPP as the most sensitive metrics for onset-based group differences in voice characteristics. ConclusionsThe findings from the study highlight the role of acoustical voice evaluation (especially CPP, F2 & F3) in verifying the onset of ANSD disorder. The insights from the onset-based differences seen in vocal characteristics can indirectly help audiologists in deciding the management options for ANSD.

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.

Cochlear implantation in auditory neuropathy spectrum disorders: role of transtympanic electrically evoked auditory brainstem responses and serial neural response telemetry.

To evaluate the utility of pre-operative transtympanic electrically evoked auditory brainstem responses and post-operative neural response telemetry in auditory neuropathy spectrum disorder patients. Four auditory neuropathy spectrum disorder patients who had undergone cochlear implantation and used it for more than one year were studied. All four patients underwent pre-operative transtympanic electrically evoked auditory brainstem response testing, intra-operative and post-operative (at 3, 6 and 12 months after switch-on) neural response telemetry, and out-patient cochlear implant electrically evoked auditory brainstem response testing (at 12 months). Patients with better waveforms on transtympanic electrically evoked auditory brainstem response testing showed superior performance after one year of implant use. Neural response telemetry and electrically evoked auditory brainstem response measures improved in all patients. Inferences related to cochlear implantation outcomes can be based on the waveform of transtympanic electrically evoked auditory brainstem responses. Robust transtympanic electrically evoked auditory brainstem responses suggest better performance. Improvements in electrically evoked auditory brainstem responses and neural response telemetry over time indicate that electrical stimulation is favourable in auditory neuropathy spectrum disorder patients. These measures provide an objective way to monitor changes and progress in auditory pathways following cochlear implantation.

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.

Auditory synaptopathy, auditory neuropathy, and cochlear implantation.

Cochlear implantation has become the standard‐of‐care for adults and children with severe to profound hearing loss. There is growing evidence that qualitative as well as quantitative deficits in the auditory nerve may affect cochlear implant (CI) outcomes. Auditory neuropathy spectrum disorder (ANSD) is characterized by dysfunctional transmission of sound from the cochlea to the brain due to defective synaptic function or neural conduction. In this review, we examine the precise mechanisms of genetic lesions causing ANSD and the effect of these lesions on CI outcomes. Reviewed data show that individuals with lesions that primarily affect the cochlear sensory system and the synapse, which are bypassed by the CI, have optimal CI outcomes. Individuals with lesions that affect the auditory nerve show poor performance with CIs, likely because neural transmission of the electrical signal from the CI is affected. We put forth a nuanced molecular classification of ANSD that has implications for preoperative counseling for patients with this disorder prior to cochlear implantation. We propose that description of ANSD patients should be based on the molecular site of lesion typically derived from genetic evaluation (synaptopathy vs. neuropathy) as this has implications for expected CI outcomes. Improvements in our understanding of genetic site of lesions and their effects on CI function should lead to better CI outcomes, not just for individuals with auditory neuropathy, but all individuals with hearing loss.

Targeted next generation sequencing reveals OTOF mutations in auditory neuropathy spectrum disorder

ObjectiveTo study the genetic etiology of auditory neuropathy spectrum disorder (ANSD) in a Chinese family and perform a literature review of OTOF mutations and cochlear implantation (CI). MethodsSequential targeted next generation sequencing (NGS) and CI was performed for the proband. Further, 50 DNA samples from unrelated families with nonsyndromic deafness were examined for frequency determination. The impact of OTOF mutations on hearing recovery after CI was assessed through the literature survey. ResultsIn the proband, the targeted NGS panel revealed five suspected variants in four genes (OTOF, EYA4, PCDH15, and GIPC3), of which two mutations—c.5098G > C (p.Glu1700Gln) and c.1702C > T (p.Arg568Trp)—in the OTOF gene were found to be correlated with ANSD. The c.5098G > C allele was identified in only one child from the 50 unrelated participants. The proband's hearing and speech abilities were restored 2 years after the surgery. Most ANSD patients (90.9%; 30/33) with OTOF mutations have acceptable surgical outcomes, as indicated by existing reports. ConclusionsOur results support the feasibility of CI for patients with ANSD and OTOF mutations, and this hypothesis was supported by the review of existing data. A larger number of cases studies is required to determine possible modifies on the prognosis of surgery.

Clear speech perception in patients with auditory neuropathy spectrum disorder

Introduction: One of the main characteristic of auditory neuropathy spectrum disorder (ANSD) is a significantly impaired temporal processing ability with subsequent difficulty in speech understanding particularly in noise. Enhancing temporal properties in clear speech can be beneficial in enhancing speech intelligibility in ANSD patients. Clear speech was developed in English language.Objective: To develop and standardize Arabic clear speech materials and to evaluate performance of patients with ANSD and sensory neural hearing loss (SNHL) in developed Arabic clear speech.Patients and Methods: The present study was conducted in three phases. Phase one; developing and recording of clear and conversational Arabic speech materials. Phase two; establishing norms in the developed materials by evaluation of 30 adult normal subjects. Phase three; comprised evaluation of performance of 30 adult SNHL patients and 40 adult patients with ANSD. Patients were tested in quiet as well as in noisy listening conditions.Results: Clear speech advantage in ANSD patients was 16.7% over conversational speech, while it was 5% in patients with SNHL. All patients with ANSD performed more poorly in noise at all signal to noise ratios (SNRs).Conclusion: The advantage of clear speech over conversational speech was more evident in ANSD patients than SNHL group. ANSD patients derive this advantage from enhancement of temporal properties in clear speech most likely. This study suggested using clear speech in remediation of patients with ANSD in order to improve their ability to communicate.

Intraoperative Electrocochleographic Characteristics of Auditory Neuropathy Spectrum Disorder in Cochlear Implant Subjects.

Auditory neuropathy spectrum disorder (ANSD) is characterized by an apparent discrepancy between measures of cochlear and neural function based on auditory brainstem response (ABR) testing. Clinical indicators of ANSD are a present cochlear microphonic (CM) with small or absent wave V. Many identified ANSD patients have speech impairment severe enough that cochlear implantation (CI) is indicated. To better understand the cochleae identified with ANSD that lead to a CI, we performed intraoperative round window electrocochleography (ECochG) to tone bursts in children (n = 167) and adults (n = 163). Magnitudes of the responses to tones of different frequencies were summed to measure the “total response” (ECochG-TR), a metric often dominated by hair cell activity, and auditory nerve activity was estimated visually from the compound action potential (CAP) and auditory nerve neurophonic (ANN) as a ranked “Nerve Score”. Subjects identified as ANSD (45 ears in children, 3 in adults) had higher values of ECochG-TR than adult and pediatric subjects also receiving CIs not identified as ANSD. However, nerve scores of the ANSD group were similar to the other cohorts, although dominated by the ANN to low frequencies more than in the non-ANSD groups. To high frequencies, the common morphology of ANSD cases was a large CM and summating potential, and small or absent CAP. Common morphologies in other groups were either only a CM, or a combination of CM and CAP. These results indicate that responses to high frequencies, derived primarily from hair cells, are the main source of the CM used to evaluate ANSD in the clinical setting. However, the clinical tests do not capture the wide range of neural activity seen to low frequency sounds.

Novel compound heterozygous mutations in the OTOF Gene identified by whole-exome sequencing in auditory neuropathy spectrum disorder

BackgroundMany hearing-loss diseases are demonstrated to have Mendelian inheritance caused by mutations in single gene. However, many deaf individuals have diseases that remain genetically unexplained. Auditory neuropathy is a sensorineural deafness in which sounds are able to be transferred into the inner ear normally but the transmission of the signals from inner ear to auditory nerve and brain is injured, also known as auditory neuropathy spectrum disorder (ANSD). The pathogenic mutations of the genes responsible for the Chinese ANSD population remain poorly understood.MethodsA total of 127 patients with non-syndromic hearing loss (NSHL) were enrolled in Guangxi Zhuang Autonomous Region. A hereditary deafness gene mutation screening was performed to identify the mutation sites in four deafness-related genes (GJB2, GJB3, 12S rRNA, and SLC26A4). In addition, whole-exome sequencing (WES) was applied to explore unappreciated mutation sites in the cases with the singularity of its phenotype.ResultsWell-characterized mutations were found in only 8.7% (11/127) of the patients. Interestingly, two mutations in the OTOF gene were identified in two affected siblings with ANSD from a Chinese family, including one nonsense mutation c.1273C > T (p.R425X) and one missense mutation c.4994 T > C (p.L1665P). Furthermore, we employed Sanger sequencing to confirm the mutations in each subject. Two compound heterozygous mutations in the OTOF gene were observed in the two affected siblings, whereas the two parents and unaffected sister were heterozygous carriers of c.1273C > T (father and sister) and c.4994 T > C (mother). The nonsense mutation p.R425X, contributes to a premature stop codon, may result in a truncated polypeptide, which strongly suggests its pathogenicity for ANSD. The missense mutation p.L1665P results in a single amino acid substitution in a highly conserved region.ConclusionsTwo mutations in the OTOF gene in the Chinese deaf population were recognized for the first time. These findings not only extend the OTOF gene mutation spectrum for ANSD but also indicate that whole-exome sequencing is an effective approach to clarify the genetic characteristics in non-syndromic ANSD patients.

High frequency of OTOF mutations in Chinese infants with congenital auditory neuropathy spectrum disorder.

Auditory neuropathy spectrum disorder (ANSD) is one of the most common diseases leading to hearing and speech communication barriers in infants and young children. The OTOF gene is the first gene identified for autosomal recessive non-syndromic ANSD, and patients with OTOF mutations have shown marked improvement of auditory functions from the cochlear implantation, but the true involvement of OTOF mutations in Chinese ANSD patients is still unknown which precludes the effective management of this disease. Here, we investigated the contribution of OTOF mutations to congenital ANSD patients in China. In all, 37 infants and young Children with ANSD were screened for all the exons of OTOF gene, of them 34 patients had no neonatal risk factors who were considered as congenital ANSD. The clinical manifestation and audiometric features were also investigated and compared in patients with and without OTOF mutations. In all, 14 of these subjects were shown to carry two or three mutant alleles of OTOF with the high frequency of 41.2% in congenital ANSD patients. In total, 15 novel pathogenic mutations and 10 reported mutations were identified. Our results confirmed that mutations in OTOF gene were a major cause of congenital ANSD in China. Identification of OTOF mutations can facilitate diagnosis, clinical intervention and counseling for congenital ANSD.

Auditory N1-P2 Cortical Event Related Potentials in Auditory Neuropathy Spectrum Disorder Patients

OBJECTIVE: The purpose of this study was to determine whether a group of patients with auditory neuropathy have abnormal changes in auditory N1-P2 and to analyze the results in those patients and compare them with matched group of normal subjects. MATERIALS and METHODS: Cortical auditory evoked potentials were obtained from nine female and seven male patients with auditory neuropathy, ranging in age from 19 to 48 years. The control group comprised 15 (9 males and 6 females) age-matched, normally hearing adults. Cortical auditory evoked potentials were recorded in both groups. Audiological assessments were performed in both groups, which included pure tone audiometry, speech audiometry, tympanometry, acoustic reflex, distortion products otoacoustic emissions, as well as auditory brainstem potential testing. RESULTS: N1-P2 amplitudes were reduced and latencies were prolonged in the study group, and these parameters were found to be statistically significant when compared to normal subjects (p<0.05). CONCLUSION: The neurophysiologic measures of auditory processing-i.e., N1-P2 response to tonal frequency stimuli-in auditory neuropathy spectrum disorder patients are found to be different. Hence, arguing a doubt on the affection of hypothesize origin of the N1-P2 potential in ANSD

Analysis of Speech Perception Outcomes Among Patients Receiving Cochlear Implants With Auditory Neuropathy Spectrum Disorder

Cochlear implantation (CI) is currently the main device option for children with auditory neuropathy spectrum disorder (ANSD) who receive minimal benefit from conventional amplification. This study examines potential prognostic factors associated with post-CI speech performance in this population. Retrospective chart review. Academic center. ANSD patients without inner ear abnormalities implanted with unilateral or bilateral CI between 1998 and 2010. CI and speech perception testing. Post-CI speech perception testing at 50 dBHL. "Good" performers were defined as patients with greater than 70% speech perception and "poor" performers less than 70%. Medical comorbidity, educational information, and social history were gathered. Twenty-seven patients met inclusion criteria. Mean age at diagnosis, first CI, and second CI in good performers were 2.5 ± 3.4, 3.4 ± 3.6, and 3.8 ± 1.6 years, respectively, compared with 9.7 ± 7.8, 14.8 ± 12.9, and 8.9 ± 3.5 in poor performers. Mean speech perception after first and second implantation for good performers trended at 85% and 90%, respectively, compared with 36% and 73% in poor performers. Better pre-CI PTA correlated with better post-CI speech perception. Patients with bilateral CI demonstrated better speech perception outcomes compared with unilateral CI use. Poor performers had later age of implantation, lower socioeconomic status, and lack of family support compared with good performers. ANSD patients who do not benefit from conventional amplification do well when implanted at a young age with proper access to education and habilitation training. Medical, social, and economic information may be helpful in predicting positive outcomes.

Relationship Between Electrically Evoked Auditory Brainstem Response and Auditory Performance After Cochlear Implant in Patients With Auditory Neuropathy Spectrum Disorder

To analyze the pattern of electrically evoked auditory brainstem response (EABR) in auditory neuropathy spectrum disorder (ANSD) patients and to compare their performances with controls. Retrospective analysis. Tertiary referral center. Eleven patients with ANSD and 9 control subjects with sensorineural hearing loss who did not have neural pathology. Diagnostic. Patients and control subjects each received a cochlear implant (CI) and underwent EABR. EABR threshold, wave V latency, and amplitude were measured as EABR parameters. The results of EABR were categorized as good response, variable response, or no response. Speech perception ability was assessed by the categories of auditory performance (CAP) score. All controls responded to EABR, whereas 6 of the 11 ANSD patients did not respond to EABR. The EABR threshold of the ANSD patients was measured almost within the value of disease controls. However, the Wave V latency displayed variable lengths, and the amplitude showed a wider distribution compared with the value of the disease control. The EABR response group among the ANSD patients showed relatively good performance after CI. In contrast, the nonresponse group demonstrated variable outcomes, although all of them still benefited from CI. The data suggested that all ANSD patients require CI and that EABR results can help establish realistic expectations about future performance. Even if electrical stimulation fails to generate sufficiently synchronized signal for eliciting EABR, CI provides at least partial, measurable auditory benefit in ANSD.

Objective hearing threshold estimation in children with auditory neuropathy spectrum disorder

Laryngoscope, 123:2859–2861, 2013

Cochlear Implantation versus Hearing Amplification in Patients with Auditory Neuropathy Spectrum Disorder

Patients with auditory neuropathy spectrum disorder (ANSD) exhibit altered neural synchrony in response to auditory stimuli. Cochlear implantation (CI) is thought to improve neural synchrony in response to auditory stimuli and improve speech perception relative to conventional hearing amplification (HA). Retrospective review. Tertiary otologic practice. Subjects included patients with ANSD treated at Vanderbilt University from 1999 to 2011. Sixteen patients underwent CI, and 10 received binaural HAs. Pretreatment performance was assessed through speech reception thresholds and parent questionnaire (Infant-Toddler Meaningful Auditory Integration Scale [IT-MAIS]). Posttreatment outcomes were assessed using IT-MAIS and closed-/open-set speech perception scores. Two HA users underwent neuromaturation and were excluded from further analysis. For the remaining patients, median duration of device use was 48 months. All CI patients had a prior binaural HA trial with failure of auditory skills development. Median available pretreatment IT-MAIS score was 13 and 30 for CI and HA groups, respectively (rank sum test, P = .32). Posttreatment, 6 of 16 CI patients and 4 of 8 HA patients achieved open-set speech perception scores ≥ 60%. No differences between groups were found in posttreatment IT-MAIS scores (rank sum test, P = .11) or the percentage of patients achieving the above levels of open-set speech perception (Fisher exact test, P = .67). A wide range of speech perception outcomes are observed in ANSD patients. In our ANSD population, patients who exhibited failure of auditory skills development with HAs were able to achieve comparable overall speech perception outcomes after CI relative to those who continued to make appropriate auditory progress with HAs alone.

Stimulation Rate Reduction and Auditory Development in Poorly Performing Cochlear Implant Users With Auditory Neuropathy

Patients with auditory neuropathy spectrum disorder (ANSD) exhibit altered neural synchrony in response to auditory stimuli. It has been hypothesized that a slower rate of electrical stimulation in programming strategies for cochlear implant (CI) users with ANSD may enhance development of neural synchrony and speech perception abilities. Retrospective case series. Tertiary otologic practice. Twenty-two patients with ANSD underwent CI. Patients with complete postoperative audiometric data and at least 2 years of follow-up were included in further analysis. Thirteen patients patients met inclusion criteria. Five "poorly performing" CI recipients with ANSD who had not developed closed-set speech perception abilities despite at least 2 years of implant use underwent implant programming to lower the neural stimulation rate. Speech perception abilities over time using parent questionnaire, closed-set testing, and open-set measures. A high incidence of comorbid conditions was present in the poor performers, including cognitive delay (n = 2), motor delay (n = 3), and autism spectrum disorder (n = 1). The median time to rate slowing in 5 poor performers was 29 months after implant activation. Three of 5 patients achieved closed-set speech perception scores higher than 60% after 6 to 16 months of implant use at the slower rates. At last follow-up (median, 42 mo), no poor performer had yet achieved open-set speech perception abilities. Of all CI recipients with ANSD included in analysis, open-set speech perception abilities developed in 46% (6/13). In CI recipients with ANSD who demonstrate limited auditory skills development despite prolonged implant use, lowering the stimulation rate may facilitate acquisition of closed-set speech perception abilities. Further efforts on the study of programming parameters in ANSD patients with CIs are necessary to maximize auditory development in this patient population.

Extra‐tympanic Electrocochleography in Auditory Neuropathy Spectrum Disorder

Objective: Compare electrocochleography (ECochG) recordings obtained simultaneously at the round window (RW) and tympanic membrane (TM) in patients with auditory neuropathy spectrum disorder (ANSD) in order to validate a noninvasive method for assessing site of lesion in these patients. Better understanding of site of lesion may help optimize intervention strategy and ultimately, performance among ANSD children. Method: ECochG responses were recorded simultaneously at the TM and RW using single pulse and trains of clicks and tone-burst stimuli during cochlear implantation in ANSD children. Recorded potentials included the cochlear microphonic (CM) and nerve compound action potential (CAP). Correlation between RW and TM ECochG recordings were analyzed using Pearson correlation test. Results: ECochG responses were successfully recorded at both the TM and RW simultaneously from 7 ANSD patients using all 4 paradigms. Both sites (TM and RW) revealed similar response patterns although RW responses were at least 1 order of magnitude greater than the TM responses. For all patients and conditions tested, the TM and RW ECochG recordings were significantly correlated in 88% of cases. A clear CAP was recorded from a subset of patients. Also, in the click train condition, in patients with a CAP response, the amplitude was noted to rapidly decrease following the first 3 to 4 stimuli. Conclusion: RW ECochG recordings have larger amplitudes and better morphology than TM recordings, but still showed positive correlation in most cases. The CAP morphology recorded from a subset of our subjects is consistent with previous literature. CAP amplitude decrement in the click train condition indicates neural adaptation in ANSD.