Auditory neuropathy spectrum disorder (ANSD) in referrals from neonatal hearing screening at a well-baby clinic

An eight-year follow-up on auditory outcomes after neonatal hearing screening

OBJECTIVE

The aim of this study is to assess the neonatal click Auditory Brainstem Response (ABR) results in relation to the subsequently determined mean hearing loss (HL) over 1, 2 and 4 kHz, as well as over 2 and 4 kHz.

METHODS

Between 2004-2009, follow-up data were collected from Visual Reinforcement Audiometry (VRA) at 1 and 2 years and playaudiometry at 4 and 8 years of newborns who had failed neonatal hearing screening in the well-baby clinics and who had been referred to a single Speech and Hearing center. Hearing Level data were compared with ABR threshold-levels established during the first months of life. The Two One-Sided Tests equivalence procedure for paired means was applied, using a region of similarity equal to 10 dB.

RESULTS

Initially, in 135 out of 172 children referred for diagnostic procedures hearing loss was confirmed in the neonatal period. In 106/135 of the HL children the eight-year follow-up was completed. Permanent conductive HL was established in 5/106 cases; the hearing thresholds were predominantly stable over time. Temporary conductive HL was found in 48/106 cases and the loss disappeared by 4 years of age at the latest. Sensorineural hearing loss (SNHL) was found in 53/106 cases, of which 13 were unilateral and 40 bilateral. ABR levels were equivalent (within a 10 dB range) to VRA levels at age 1 and 2 and play audiometry levels at age 4 and 8, both when VRA and play audiometry were averaged over both frequency ranges.

CONCLUSION

Long term follow-up data of children with SNHL suggest that the initial click ABR level established in the first months of life, are equivalent to the hearing threshold measured at the age of 1, 2, 4 and 8 years for both mean frequency ranges. Click ABR can reliably be used as starting point for long-term hearing rehabilitation.

Prevalence and Auditory Characteristics of Auditory Neuropathy Spectrum Disorder in Adult Population with Sensory Neural Hearing Loss: A Hospital Based Study in South India

Auditory neuropathy spectrum disorder (ANSD) is a heterogenous group of disorder characterized by abnormalities in auditory brainstem responses (ABR) with preserved otoacoustic emissions and/or cochlear microphonics. The aim of the study is to estimate the prevalence and evaluate the audiological characteristics of ANSD in adult population with sensory neural hearing loss. A prospective study was conducted on the adult population (≥ 18 years) attending ENT outpatients clinic at Rajiv Gandhi Government General Hospital, Chennai. All patients reported to the department with auditory and vestibular symptoms underwent case history, otoscopic examination, and routine audiological evaluation (pure tone audiometry, speech audiometry and immittance audiometry). Patients with indications of ANSD in case history and routine audiological evaluation were further evaluated using distortion product otoacoustic emissions and ABR. A total of 8682 adult population was evaluated during the period of 2017 to 2018. Out of 8682 patients, 1343 (15.46%) of them had sensory neural hearing loss of varying degrees. Out of 1343 adults with sensory neural hearing loss, 24 (1.78%) adults were diagnosed as ANSD. The prevalence of ANSD in adult population with sensory neural hearing loss in our study is 1.32% per 1000 adults. The clinical characteristics of ANSD shows impairment in speech perception irrespective of degree of hearing loss, preserved cochlear functions and abnormal ABR. Hence ANSD is not a rare clinical finding in adults with sensory neural hearing loss, but its prevalence was estimated to be lower in Indian population. Often young females are affected causing significant impairment in speech perception and disability.

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

Objective

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

Methods

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

Results

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

Conclusion

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

Identification of a novel AIFM1 variant from a Chinese family with auditory neuropathy

Background: Auditory neuropathy (AN) is a specific type of hearing loss characterized by impaired language comprehension. Apoptosis inducing factor mitochondrion associated 1 (AIFM1) is the most common gene associated with late-onset AN. In this study, we aimed to screen the pathogenic variant of AIFM1 in a Chinese family with AN and to explore the molecular mechanism underlying the function of such variant in the development of AN.

Methods: One patient with AN and eight unaffected individuals from a Chinese family were enrolled in this study. A comprehensive clinical evaluation was performed on all participants. A targeted next-generation sequencing (NGS) analysis of a total of 406 known deafness genes was performed to screen the potential pathogenic variants in the proband. Sanger sequencing was used to confirm the variants identified in all participants. The pathogenicity of variant was predicted by bioinformatics analysis. Immunofluorescence and Western blot analyses were performed to evaluate the subcellular distribution and expression of the wild type (WT) and mutant AIFM1 proteins. Cell apoptosis was evaluated based on the TUNEL analyses.

Results: Based on the clinical evaluations, the proband in this family was diagnosed with AN. The results of NGS and Sanger sequencing showed that a novel missense mutation of AIFM1, i.e., c.1367A > G (p. D456G), was identified in this family. Bioinformatics analysis indicated that this variant was pathogenic. Functional analysis showed that in comparison with the WT, the mutation c.1367A > G of AIFM1 showed no effect on its subcellular localization and the ability to induce apoptosis, but changed its protein expression level.

Conclusion: A novel variant of AIFM1 was identified for the first time, which was probably the genetic cause of AN in a Chinese family with AN.

Cochlear nerve deficiency is an important cause of auditory neuropathy spectrum disorder at a population level in children

OBJECTIVES

To determine the incidence, prevalence and describe risk factors and etiology for childhood Auditory Neuropathy Spectrum Disorder using population level data from a statewide universal newborn hearing program.

METHODS

A retrospective statewide universal newborn hearing screening database review and descriptive analysis from 2012 to 2019 of demographic, risk factors and hearing loss etiology for babies with sensorineural hearing loss and ANSD was completed. A 2 stage aABR protocol was used and ANSD was classified when click evoked ABR were absent or grossly abnormal but otoacoustic emissions and or cochlear microphonics were present. Medical evaluation and investigation by a pediatrician or otolaryngologist was performed and etiology was assigned using a coding scheme. Next generation genetic sequencing was not available.

RESULTS

From 2012 to 2019, 487 636 babies were screened for congenital hearing loss (99.1%) and 1150 were confirmed to have permanent SNHL, 80 of whom were diagnosed with ANSD (52 unilateral and 28 bilateral). The prevalence of ANSD was 7.0% and population prevalence was 0.16 per 1000 live births. The only demographic or risk factor significantly more likely to be associated with ANSD than SNHL was hyperbilirubinemia. The most common etiology for ANSD was hypoplasia or absence of the cochlear nerve with 37 cases (46.3%), and it was significantly more likely with unilateral than bilateral ANSD.

CONCLUSION

At a population level, ANSD was more likely to be unilateral and the only perinatal risk factor significantly associated was hyperbilirubinemia. Cochlear nerve deficiency was the most common etiology. Given that this can occur in well babies, this provides further evidence for aABR as a preferred mode for newborn hearing screening.

Genetic testing for pediatric hearing loss: no time to waste

Since the discovery of the first human deafness gene a quarter of a century ago, our approach to clinical evaluation of children with hearing loss has changed dramatically. What was once a low-yield scattershot approach has changed to a clearly definable pathway involving genetic testing, imaging, and congenital cytomegalovirus testing. There still however is a great deal of work to be done to expand the correct use of this testing, particularly genetic testing.

[Auditory neuropathy and prematurity: modern view of the issue (literature review)]

Auditory neuropathy spectrum disorder (ANSD) is a specific auditory disorder caused by dysfunction of periphery part of the auditory system, in which the function of the outer hair cells is preserved, but the afferent input at the cochlear level suffers due to the pathology of the inner hair cells, neurons of the spiral ganglion and/or the auditory nerve, as well as synaptic contact between them. As a result, a specific condition is formed, in which a patient's otoacoustic emissions and/or cochlear microphonics are present, auditory brainstem responses are abnormal or absent, the discrepancy between the hearing level and the electrophysiological data, poor speech perception which may not correlate with the hearing thresholds. ANSD is a multifactorial disease. One of the main risk factors is perinatal pathology and, in particular, prematurity. The possible factors associated with prematurity that provoke the onset of the disease, features of the pathogenesis, clinical and audiological peculiarities of ANSD in premature infants, contemporary approaches to the habilitation of such patients are discussed in the article. The necessity of an individual, patient-oriented approach to the treatment of premature infants with ANSD is substantiated; such an approach should be based both on the genesis of the disorder, taking into account possible points of lesion in the auditory system, and the developmental peculiarities of a premature baby considering the presence of concomitant diseases associated with prematurity. In the article attention is focused on the main directions of habilitation work with such children, including a multidisciplinary approach, regular careful monitoring of the auditory, speech and language skills, intensive psychological and speech therapist support, the choice of an adequate way of intervention and its improvement as necessary.

New-born Hearing Screening Programmes in 2020: CODEPEH Recommendations

Programmes for early detection of congenital hearing loss have been successfully implemented mainly in developed countries, after overcoming some conceptual errors argued against their implementation and some criticism of their efficacy. However, some difficulties and weaknesses are still identified in these programmes: the detection of late-onset hearing loss and the percentage of children who did not pass the screening and did not complete the process of diagnosis and treatment, these being cases that are lost in the process. The purpose of this Document is to analyse these problems to determine areas for improvement and to emphasize one of the basic principles for the success of the programmes: continuous training for the interdisciplinary team. The result of the review process carried out by CODEPEH has been drafted as Recommendations for updating the Programmes with the evidence of the last decade, including advances in screening technology, the impact of the present knowledge on congenital infection by cytomegalovirus, genetic hearing loss research and control systems of lost to follow-up cases, treatment and follow up.

Emerging Data from a Newborn Hearing Screening Program in Sharjah, United Arab Emirates

Objectives

Newborn hearing screening (NHS) plays a critical role in early identification of hearing loss and subsequent early habilitation. Active parental involvement influences the success of NHS, particularly the initial NHS and follow-up. The current study reports the results of an NHS program in a cohort of babies born in a tertiary care hospital in Sharjah, United Arab Emirates (UAE). Further, it explores a two-stage NHS model to reduce false responses, thereby alleviating parental anxiety.

Methods

Retrospective observational study was conducted for a period of five years from January 2017 to December 2020. NHS was done as a two-stage model. All the healthy newborn babies were screened using Automated Auditory Brainstem Response (AABR) by trained audiology professionals. Babies who failed the first NHS were followed up after two weeks. Further, babies that failed the follow-up NHS were sent for diagnostic hearing evaluation and intervention as necessary.

Results

A total of 1821 newborn babies were screened during the study period. Eighty-one percent of babies passed the initial NHS. Four hundred and twenty-three (23.22%) babies were referred on the first NHS and were followed up after 2 weeks. Among these babies, 7.03% (24) failed second NHS. Nine (37.50%) of the 24 babies were confirmed to have hearing loss in both ears. The incidence of hearing loss in our cohort was 4.94 per 1000. Confirmed hearing loss was statistically higher in boys than girls (p < 0.05).

Conclusion

Current study was an attempt to report the emerging NHS data as part of the implementation of an NHS program. The study findings emphasize the need for a two-stage model of NHS to rule out false responses.

Comprehensive evaluation of risk factors for neonatal hearing loss in a large Brazilian cohort

OBJECTIVES

To determine the incidence and risk factors of hearing loss (HL) in Brazilian neonates.

STUDY DESIGN

11,900 neonates were screened for hearing and congenital CMV (cCMV). Low and high-risk babies who did not pass their hearing screening and infants with cCMV were scheduled for a diagnostic audiologic evaluation.

RESULTS

The incidence of HL was 2 per 1000 live-born infants (95% CI: 1-3). HL was higher in high-risk neonates than in low risk babies (18.6 vs. 0.3/1000 live births, respectively). Among infants exposed to isolated risk factors, association of HL with craniofacial abnormalities/syndromes (RR = 24.47; 95% CI: 5.9-100.9) and cCMV (RR = 9.54; 95% CI: 3.3-27.7) were observed. HL was 20 to 100-fold more likely in neonates exposed to ototoxic drugs in combination with cCMV or craniofacial/congenital anomalies.

CONCLUSIONS

Strategies for the prevention of cCMV and exposure to ototoxic drugs may decrease the incidence of HL in this population.

Novel Mutation in AIFM1 Gene Associated with X-Linked Deafness in a Moroccan Family

INTRODUCTION

Auditory neuropathy is a hearing disorder where outer hair cell function within the cochlea is normal, but inner hair cell and/or the auditory nerve function is disrupted. It is a heterogeneous disorder, which can have either congenital or acquired causes.

METHODS

We found a disease-segregating mutation in the X-linked AIFM1 gene through whole-exome sequencing, encoding the apoptosis-inducing factor mitochondrion-associated 1.

RESULTS

The impact of the c.1045A>G; p.(Ser349Gly) mutation on the AIFM1 protein was predicted using different bioinformatics tools. The pedigree analysis in the examined family was consistent with X-linked dominant inheritance.

DISCUSSION/CONCLUSION

To our knowledge, this is the first study that identifies a mutation in the AIFM1 gene in Moroccan patients suffering from X-linked auditory neuropathy.

Etiological Work-up in Referrals From Neonatal Hearing Screening: 20 Years of Experience

BACKGROUND

Confirmation of permanent hearing loss in a newborn should be followed by a search for an underlying etiology because this may impact hearing loss management and counselling.

METHODS

Retrospective chart review of all newborns seen at a tertiary referral center after referral from newborn hearing screening over a 20-year period. The changes in the diagnostic protocol over the years are outlined and the most recent protocol includes targeted next-generation sequencing using a panel for known hearing loss causing genes, in all cases of bilateral sensorineural hearing loss (SNHL).

RESULTS

Permanent hearing loss was confirmed in 235 of 1,002 neonates. A complete etiological work-up was performed in 138 cases of SNHL (77 bilateral and 61 unilateral), with the underlying cause found in 77.9% and in 67.2% of patients respectively. Genetic causes explained 55 (58.4%) of bilateral cases and in 17 a genetic cause was identified by the gene panel. Pathogenic variants in GJB2 and MYO15A explained most cases of nonsyndromic SNHL. Waardenburg syndrome was the most frequent syndromic cause. Cochlear nerve deficiency and congenital cytomegalovirus infection accounted for the majority of unilateral SNHL.Other causes of congenital hearing loss were conductive hearing loss (n = 12) and auditory neuropathy/dyssynchrony (n = 9).

CONCLUSION

Implementation of targeted next-generation sequencing in the etiological work-up improves the diagnostic yield in congenital SNHL, leaving only about 20% of bilateral and 30% of unilateral cases unsolved.

Brain Functional Alterations in Long-term Unilateral Hearing Impairment

BACKGROUND

The rate of patients with unilateral hearing impairments (UHI) increase with age and are characterized by asymmetric auditory afferents in which auditory information is asymmetrically transmitted to the brain. Long-term bilateral hearing imbalance can cause abnormal functional changes in the cerebral cortex. However, the relationship between functional alterations in the brain and the severity of the hearing impairment remains unclear.

METHODS

This study included 33 patients with UHI (left-sided impairment in 17 and right-sided impairment in 16) and 32 healthy patients. All participants underwent resting-state, blood oxygen level dependent functional magnetic resonance imaging. Fractional amplitude of low frequency fluctuation (fALFF) values were calculated after data preprocessing and compared among the left-sided and right-sided impairment groups and the control group. Pure tone audiometry was used to evaluate patients' hearing impairment level. The correlation between fALFF values of abnormal brain regions and the duration and severity of hearing impairment was analyzed.

RESULTS

Results provide evidence for altered resting-state functional activities in the brain of patients with left or right long-term UHI, with significantly increased fALFF values in the Heschl's gyrus, superior temporal gyrus, and insula were observed. Moreover, complicated networks reorganization involved in the visual, cognitive, sensorimotor and information transmission functions except for the auditory function and some brain regions exhibited functional changes only in the one-sided impairment group. In addition, the severity of hearing impairment is related with the functional activities in the bilateral Heschl's gyrus, bilateral insula, right superior temporal gyrus, and left middle frontal gyrus.

CONCLUSION

In conclusion, alterations in functional activity are observed in the brains of patients with long-term hearing impairments and multiple brain regions within different functional networks are involved in the brain functional remodeling. The brain reintegration mechanism appears to be asymmetrical and the lateralization pattern in the contralateral brain hemisphere for auditory information processing related with the severity of hearing impairment.

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.

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.

Lessons From an Analysis of Newborn Hearing Screening Data for Children With Cochlear Implants

OBJECTIVES

The aims of the study are to identify the limitations of the current newborn hearing screening (NHS) programs and provide recommendations for better protocols.

STUDY DESIGN

Retrospective analysis.

SETTING

Tertiary referral center.

PATIENTS

The study participants were 185 children who received cochlear implants (CIs) at ≤5 years of age.

INTERVENTIONS

Therapeutic and rehabilitative.

MAIN OUTCOME MEASURES

The results of NHS, screening tools used, age, and hearing thresholds at which hearing loss was confirmed, causes of the hearing loss, age of CI insertion, aided pure-tone audiogram findings, and language development level were analyzed.

RESULTS

NHS data was available for 109 children, and 24 patients (22.0%) had passed NHS for both ears. Hearing loss was confirmed considerably later in children who had passed NHS than in children who were referred for further evaluation (p < 0.01). The most common cause for hearing loss in the NHS-pass group was SLC26A4 mutations (41.7%). Patients in the NHS-pass group received CIs considerably later than those in the NHS-referred group (p < 0.01). Among patients with SLC26A4 mutations, the language development level was significantly lower in the NHS-pass group than in the NHS-referred group (p < 0.01).

CONCLUSIONS

Careful counseling regarding NHS results is necessary for parents to understand that the absence of hearing loss at birth does not mean that the child will not develop hearing loss later in life. Genetic testing for SLC26A4 mutations may be necessary in regions with a high incidence of these mutations, such as East Asia.

Unilateral congenital hearing loss in children: Challenges and potentials

The estimated incidence of sensorineural hearing impairment (>40 dB HL) at birth is 1.86 per 1000 newborns in developed countries and 30-40% of these are unilateral. Profound sensorineural unilateral hearing impairment or single sided deafness (SSD) can be treated with a cochlear implant. However, this treatment is costly and invasive and unnecessary in the eyes of many. Very young children with SSD often do not exhibit language and cognitive delays and it is hard to imagine that neurocognitive skills will present difficulties with one good ear. In the current paper we review the most recent evidence on the consequences of unilateral hearing impairment for auditory and neurocognitive factors. While data of both adults and children are discussed, we focus on developmental factors, congenital deafness and a window of opportunity for intervention. We discuss which etiologies qualify for a cochlear implant and present our multi-center prospective study on cochlear implants in infants with one deaf ear. The large, state-of-the art body of research allows for evidence-based decisions regarding management of unilateral hearing loss in children.

Universal newborn hearing screening in the Lazio region, Italy

Background

The introduction of Universal Newborn Hearing Screening (UNHS) programs has drastically contributed to the early diagnosis of hearing loss in children, allowing prompt intervention with significant results on speech and language development in affected children. UNHS in the Lazio region has been initially deliberated in 2012; however, the program has been performed on a universal basis only from 2015. The aim of this retrospective study is to present and discuss the preliminary results of the UNHS program in the Lazio region for the year 2016, highlighting the strengths and weaknesses of the program.

Methods

Data from screening facilities in the Lazio region for year 2016 were retrospectively analyzed. Data for Level I centers were supplied by the Lazio regional offices; data for Level II and III centers were provided by units that participated to the study.

Results

During 2016, a total of 44,805 babies were born in the Lazio region. First stage screening was performed on 41,821 children in 37 different birth centers, with a coverage rate of 93.3%. Of these, 38.977 (93.2%) obtained a “pass” response; children with a “refer” result in at least one ear were 2844 (6.8%). Data from Level II facilities are incomplete due to missing reporting, one of the key issues in Lazio UNHS. Third stage evaluation was performed on 365 children in the three level III centers of the region, allowing identification of 70 children with unilateral (40%) or bilateral (60%) hearing loss, with a prevalence of 1.6/1000.

Conclusions

The analysis of 2016 UNHS in the Lazio region allowed identification of several strengths and weaknesses of the initial phase of the program. The strengths include a correct spread and monitoring of UNHS among Level I facilities, with an adequate coverage rate, and the proper execution of audiological monitoring and diagnosis among Level III facilities. Weakness, instead, mainly consisted in lack of an efficient and automated central process for collecting, monitoring and reporting of data and information.

Acoustic Reflex Testing in Neonatal Hearing Screening and Subsequent Audiological Evaluation

PURPOSE

The aims of the study were to examine the acoustic reflex screening and threshold in healthy neonates and those at risk of hearing loss and to determine the effect of birth weight and gestational age on acoustic stapedial reflex (ASR).

METHOD

We assessed 18 healthy neonates (Group I) and 16 with at least 1 risk factor for hearing loss (Group II); all of them passed the transient evoked otoacoustic emission test that assessed neonatal hearing. The test battery included an acoustic reflex screening with activators of 0.5, 1, 2, and 4 kHz and broadband noise and an acoustic reflex threshold test with all of them, except for the broadband noise activator.

RESULTS

In the evaluated neonates, the main risk factors were the gestational age at birth and a low birth weight; hence, these were further analyzed. The lower the gestational age at birth and birth weight, the less likely that an acoustic reflex would be elicited by pure-tone activators. This effect was significant at the frequencies of 0.5, 1, and 2 kHz for gestational age at birth and at the frequencies of 1 and 2 kHz for birth weight. When the broadband noise stimulus was used, a response was elicited in all neonates in both groups. When the pure-tone stimulus was used, the Group II showed the highest acoustic reflex thresholds and the highest percentage of cases with an absent ASR. The ASR threshold varied from 50 to 100 dB HL in both groups. Group II presented higher mean ASR thresholds than Group I, this difference being significant at frequencies of 1, 2, and 4 kHz.

CONCLUSIONS

Birth weight and gestational age at birth were related to the elicitation of the acoustic reflex. Neonates with these risk factors for hearing impairment were less likely to exhibit the acoustic reflex and had higher thresholds.

Test-retest reliability of speech-evoked auditory brainstem response in healthy children at a low sensation level

OBJECTIVE

Auditory brainstem responses evoked by complex stimuli such as speech syllables have been studied in normal subjects and subjects with compromised auditory functions. The stability of speech-evoked auditory brainstem response (speech-ABR) when tested over time has been reported but the literature is limited. The present study was carried out to determine the test-retest reliability of speech-ABR in healthy children at a low sensation level.

METHODS

Seventeen healthy children (6 boys, 11 girls) aged from 5 to 9 years (mean = 6.8 ± 3.3 years) were tested in two sessions separated by a 3-month period. The stimulus used was a 40-ms syllable /da/ presented at 30 dB sensation level.

RESULTS

As revealed by pair t-test and intra-class correlation (ICC) analyses, peak latencies, peak amplitudes and composite onset measures of speech-ABR were found to be highly replicable. Compared to other parameters, higher ICC values were noted for peak latencies of speech-ABR.

CONCLUSION

The present study was the first to report the test-retest reliability of speech-ABR recorded at low stimulation levels in healthy children. Due to its good stability, it can be used as an objective indicator for assessing the effectiveness of auditory rehabilitation in hearing-impaired children in future studies.

Newborn hearing screening protocol in tuscany region

BACKGROUND

Newborn hearing screening has to be considered the first step of a program for the identification, diagnosis, treatment and habilitation/rehabilitation of children with hearing impairment.

MAIN PART

In Tuscany Region of Italy, the universal newborn hearing screening is mandatory since november 2007. The first guidelines for the execution of the screening have been released in June 2008; then many other Italian regions partially or totally adopted these guidelines. On the basis of the experience from 2008 and according to the recent evidences in the scientific literature, a new screening protocol was released in Tuscany region. The new protocol is an evolution of the previous one. Some issues reported in the previous protocol and in the Joint Committee on Infant Hearing statement published in 2007 were revised, such as the risk factors for auditory neuropathy and for late onset, progressive or acquired hearing loss. The new updated guidelines were submitted to the Sanitary Regional Council and then they have been approved in August 2016. The updated screening protocol is mainly aimed to identify newborns with a congenital moderate-to-profound hearing loss, but it also provides indications for the audiological follow-up of children with risk's factor for progressive or late onset hearing loss; further it provides indications for the audiological surveillance of children at risk for acquired hearing impairment. Then, in the new guidelines the role of the family paediatrician in the newborn hearing screening and audiological follow-up and surveillance is underscored. Finally the new guidelines provide indications for the treatment with hearing aids and cochlear implant, in accordance with the recent Italian Health Technology Assessment (HTA) guidelines.

CONCLUSIONS

In the paper we report the modality of execution of the universal newborn hearing screening in the Tuscany Region, according to the recently updated protocol. The main features of the protocol and the critical issues are discussed.

Clinical role of electrocochleography in children with auditory neuropathy spectrum disorder

OBJECTIVES

To assess electrocochleography (ECochG) to tones as an instrument to account for CI speech perception outcomes in children with auditory neuropathy spectrum disorder (ANSD).

MATERIALS & METHODS

Children (<18 years) receiving CIs for ANSD (n = 30) and non-ANSD (n = 74) etiologies of hearing loss were evaluated with ECochG using tone bursts (0.25-4 kHz). The total response (TR) is the sum of spectral peaks of responses across frequencies. The compound action potential (CAP) and the auditory nerve neurophonic (ANN) in ECochG waveforms were used to estimate nerve activity and calculate nerve score. Performance on open-set monosyllabic word tests was the outcome measure. Standard statistical methods were applied.

RESULTS

On average, TR was larger in ANSD than in non-ANSD subjects. Most ANSD (73.3%) and non-ANSD (87.8%) subjects achieved open-set speech perception; TR accounted for 33% and 20% of variability in the outcomes, respectively. In the ANSD group, the PTA accounted for 69.3% of the variability, but there was no relationship with outcomes in the non-ANSD group. In both populations, nerve score was sensitive in identifying subjects at risk for not acquiring open-set speech perception, while the CAP and the ANN were more specific.

CONCLUSION

In both subject groups, the TRs correlated with outcomes but these measures were notably larger in the ANSD group. There was also strong correlation between PTA and speech perception outcome in ANSD group. In both subject populations, weaker evidence of neural activity was related to failure to achieve open-set speech perception.

Universal newborn hearing screening in southwestern Iran

OBJECTIVES

The implementation of Neonatal Hearing Screening (NHS) program is still at the preliminary stage particularly in developing countries despite the burden of permanent congenital and early-onset hearing impairment. The purpose of this study was to report results for universal newborn NHS in a cohort of children born in the southwestern region of Iran, as part of a national screening program set up by the Iranian National Health System.

METHODS

During this cross-sectional study, which took place between March 2013 and April 2016, healthy newborns were screened using transient evoked otoacoustic emissions (TEOAEs) and automated auditory brainstem responses (AABRs) methods at several points in time as early as possible after birth. Screening followed a two-stage strategy and newborns referred after the second-stage screening were scheduled for diagnostic evaluation.

RESULTS

A total of 92,521 newborns were screened in the urban (n = 67,780) and rural (n = 24,741) regions. Hearing impairment was confirmed in 223 (2.41 per 1000) newborns. One hundred forty-one (1.52 per 1000) of these newborns were affected bilaterally. More than 87% of these infants (195/223) showed a sensorineural hearing loss, while the defect was found to be conductive in 12 cases (P < 0.001). Of the 223 cases with hearing loss, 28 (12.5%) infants had auditory neuropathy. The majority of the infants, in both urban and rural regions, showed severe hearing impairment. We did not observe any significant difference among the incidences associated with gender (p = 0.29).

CONCLUSION

Our results demonstrated that universal newborn hearing screening program is an adequate program for southwestern of Iran with high coverage, low referral rate, and good follow-up rate.

The universal newborn hearing screening program in a public hospital: The importance of the day of examination

OBJECTIVES

Newborn hearing screening programs are already implemented in many countries worldwide. Nonetheless there is still no consensus about the most proper post-birth day of examination. The purpose of this study was to assess the most appropriate day of universal hearing screening program in a public hospital.

MATERIAL AND METHODS

A prospective cohort study was conducted in "Attiko University National Health System Hospital" and included 2494 newborns. They were examined before discharge from the hospital, using transient evoked otoacoustic emissions (TEOAEs).

RESULTS

From 2494 neonates included in the study, 2129 (85.4%) bilaterally passed the screening examination, while 365 (14.6%) failed the test. Higher levels of "pass" result per day of life were presented the third (90%) and fourth (94%) day of life. These days the referral scores were lower, reaching 6% the 4th post-birth day.

CONCLUSION

All infants should be screened for their hearing in the first days of life as otoacoustic emissions can be recorded from the first 24 h of life. If the babies stay in the maternity unit for more that 1-2 days for any reason (protocol of the maternity unit, parents leave in remote areas, etc.) we recommend the 4th day of life as the most appropriate day of examination in order to minimize the false positive ("refer") results at the initial examination.