Identification of neonatal hearing impairment: evaluation of transient evoked otoacoustic emission, distortion product otoacoustic emission, and auditory brain stem response test performance

Revisiting the transient-evoked otoacoustic emissions passing criteria used for newborn hearing screening

OBJECTIVE

To assess transient-evoked otoacoustic emissions (TEOAE) data from 15 years of a newborn hearing screening program and evaluate how well various criteria separate ears with and without hearing loss.

DESIGN

Retrospective review of TEOAE data using logistic regression, receiver operating characteristic curves, and cumulative percentage graphs.Study sample: Children with hearing loss who passed TEOAE screening as a newborn were compared to children who failed TEOAE screening and normal hearing children who either passed or failed. Exclusions were applied for acquired hearing loss or auditory neuropathy.

RESULTS

Ears with hearing loss that passed screening had significantly lower TEOAE response levels compared to ears with normal hearing. Noise levels, test times, and number of sweeps were also lower. Most of these ears had mild hearing loss. Logistic regression results showed that high-frequency TEOAE response level is the best predictor of hearing loss. A multivariate "logit" score calculated from the regression was the best indicator for separating ears with hearing loss from ears with normal hearing.

CONCLUSIONS

TEOAE response levels or an algorithm which incorporates logit scores should be considered as a minimum passing criterion to increase the sensitivity of the TEOAE screening.

Automated detection of auditory response: non-detection stopping criterion and repeatability studies for multichannel EEG

An Auditory Steady-State Response (ASSR) is a valuable tool for determining auditory thresholds in individuals who are either unable or unwilling to cooperate with conventional behavioral testing methods. This study proposes a sequential test technique for automatic detection of ASSRs, incorporating a non-detection stopping criterion. The electrophysiological thresholds of a normal hearing volunteer were established using data collected from multichannel EEG signals. The detection probabilities and critical values were obtained via Monte Carlo simulations. Remarkably, application of the non-detection stopping criterion resulted in a 60% reduction in exam time in the absence of a response. These findings clearly demonstrate the significant potential of the sequential test in enhancing the performance of automatic audiometry.

Evaluating Fixed Single-Point Parameters When Applied to Vestibular Evoked Myogenic Potentials: The Effect of Single Point and Signal Window

OBJECTIVES

Several studies have applied a common objective detection algorithm (fixed single point [ Fsp ]) for detection of the vestibular evoked myogenic potential (VEMP). However, fundamental parameters of Fsp , such as establishing the location and duration of a signal window, have not been examined. In addition, Fsp criterion values used for response detection have not been established for cervical VEMPs (cVEMPs) or ocular VEMPs (oVEMPs). The purpose of this article was to investigate the effect of various single points and signal windows on Fsp , as well as determining Fsp criteria to determine response presence for cVEMP and oVEMP in a group of young healthy participants.

DESIGN

Twenty young healthy adults under the age of 30 and with no history of hearing or balance concerns were enrolled in the study protocol. Air-conducted cVEMPs and oVEMPs were evoked using 500 Hz tone bursts at 123 dB pSPL recorded at a fixed electromyography activation of 50 µV for cVEMPs and 35° gaze angle for oVEMPs. Responses were analyzed off-line using visual and objective detection. Fsp was applied to cVEMPs and oVEMPs using a range of single points and signal windows.

RESULTS

Noise variance was lowest for cVEMPs at the latency of P1, and for oVEMPs noise variance was not significantly different across the single-point latencies. On average, extending the length of the signal window lowered the Fsp value in cVEMPs and oVEMPs. An Fsp value of 2.0 was chosen as the criterion cutoff associated with the 95th percentile during no-response conditions using group data for cVEMPs and oVEMPs, respectively. Fsp values for cVEMPs and oVEMPs were not significantly different from each other.

DISCUSSION

This study established single-point latency and time-window parameters for VEMP-related applications of the Fsp detection algorithm. Fsp criteria values were established for cVEMP and oVEMP. Using these parameters, responses were detected in all participants.

Deep Learning Models for Predicting Hearing Thresholds Based on Swept-Tone Stimulus-Frequency Otoacoustic Emissions

OBJECTIVES

This study aims to develop deep learning (DL) models for the quantitative prediction of hearing thresholds based on stimulus-frequency otoacoustic emissions (SFOAEs) evoked by swept tones.

DESIGN

A total of 174 ears with normal hearing and 388 ears with sensorineural hearing loss were studied. SFOAEs in the 0.3 to 4.3 kHz frequency range were recorded using linearly swept tones at a rate of 2 Hz/msec, with stimulus level changing from 40 to 60 dB SPL in 10 dB steps. Four DL models were used to predict hearing thresholds at octave frequencies from 0.5 to 4 kHz. The models-a conventional convolutional neural network (CNN), a hybrid CNN-k-nearest neighbor (KNN), a hybrid CNN-support vector machine (SVM), and a hybrid CNN-random forest (RF)-were individually built for each frequency. The input to the DL models was the measured raw SFOAE amplitude spectra and their corresponding signal to noise ratio spectra. All DL models shared a CNN-based feature self-extractor. They differed in that the conventional CNN utilized a fully connected layer to make the final regression decision, whereas the hybrid CNN-KNN, CNN-SVM, and CNN-RF models were designed by replacing the last fully connected layer of CNN model with a traditional machine learning (ML) regressor, that is, KNN, SVM, and RF, respectively. The model performance was evaluated using mean absolute error and SE averaged over 20 repetitions of 5 × 5 fold nested cross-validation. The performance of the proposed DL models was compared with two types of traditional ML models.

RESULTS

The proposed SFOAE-based DL models resulted in an optimal mean absolute error of 5.98, 5.22, 5.51, and 6.06 dB at 0.5, 1, 2, and 4 kHz, respectively, superior to that obtained by the traditional ML models. The produced SEs were 8.55, 7.27, 7.58, and 7.95 dB at 0.5, 1, 2, and 4 kHz, respectively. All the DL models outperformed any of the traditional ML models.

CONCLUSIONS

The proposed swept-tone SFOAE-based DL models were capable of quantitatively predicting hearing thresholds with satisfactory performance. With DL techniques, the underlying relationship between SFOAEs and hearing thresholds at disparate frequencies was explored and captured, potentially improving the diagnostic value of SFOAEs.

Analysis of audiological outcomes of children referred from a universal newborn hearing screening program over 9 years in Beijing, China

Universal newborn hearing screening (UNHS) and audiological diagnosis are crucial for children with congenital hearing loss (HL). The objective of this study was to analyze hearing screening techniques, audiological outcomes and risk factors among children referred from a UNHS program in Beijing. A retrospective analysis was performed in children who were referred to our hospital after failing UNHS during a 9-year period. A series of audiological diagnostic tests were administered to each case, to confirm and determine the type and degree of HL. Risk factors for HL were collected. Of 1839 cases, 53.0% were referred after only transient evoked otoacoustic emission (TEOAE) testing, 46.1% were screened by a combination of TEOAE and automatic auditory brainstem response (AABR) testing, and 1.0% were referred after only AABR testing. HL was confirmed in 55.7% of cases. Ears with screening results that led to referral experienced a more severe degree of HL than those with results that passed. Risk factors for HL were identified in 113 (6.1%) cases. The main risk factors included craniofacial anomalies (2.7%), length of stay in the neonatal intensive care unit longer than 5 days (2.4%) and birth weight less than 1500 g (0.8%). The statistical data showed that age (P < 0.001) and risk factors, including craniofacial anomalies (P < 0.001) and low birth weight (P = 0.048), were associated with the presence of HL. This study suggested that hearing screening plays an important role in the early detection of HL and that children with risk factors should be closely monitored.

Modified universal new-born hearing screening: Practical approach for developing world (Georgean experience)

AIM

Analysis of newborn hearing screening (NBS) outcomes and proposing a modified strategy for better performance of NBS in developing world.

DESIGN

Descriptive (retrospective and prospective) study.

METHODS

A total of 8412 newborns/neonates were subjected to risk factor assessment followed by a set of subjective (behavioral audiometry: BoA) and objective (OAE: otoacoustic emissions, ABR: auditory brainstem-evoked responses) hearing-screening in different combinations. DPOAE (primary objective tool) was undertaken in 2565 cases. Predictive value of risk factors on deafness was statistically analysed along with affectivity of objective, subjective and questionnaire-based screening tools.

RESULTS

Amongst 8412 babies, 45.5% were 'at risk' (major 36.41%, minor 9.17%). The OAE was abnormal in 299 cases (11.6% of 2565 & 3.5% in 8412). The abnormal OAE rate in prospective cases was 3.5% while in retrospective cases that underwent initial screening with BoA was 41%. A significant correlation was seen with consanguinity, high blood pressure, NICU stay>5 days, low birth weight, neonatal jaundice, delayed birth cry, pre-mature status, birth asphyxia and maternal excessive vomiting, while regression models of OAE outcome (sensitivity 99%, accuracy 89%) revealed highest predictive value for the initial 3 factors. BoA-screening revealed a sensitivity of 72.6%, and negative predictive value of 42.4%. Also a perfect correlation was evident between OAE-ABR, OAE-BoA and ABR-BoA.

CONCLUSION

A subjective NBS screening through questionnaire-based-risk-assessment and modified-BoA followed by selective referral for objective assessment is more practical and focussed approach for poor resourced countries that is likely to screen a larger population.

Ear and hearing outcomes in Aboriginal infants living in an urban Australian area: the Djaalinj Waakinj birth cohort study

OBJECTIVE

Describe the ear and hearing outcomes in Aboriginal infants in an Australian urban area.

DESIGN

Aboriginal infants enrolled in the Djaalinj Waakinj prospective cohort study had ear health screenings at ages 2-4, 6-8 and 12-18 months and audiological assessment at ∼12 months of age. Sociodemographic, environmental characteristics, otoscopy, otoacoustic emissions, tympanometry and visual reinforcement audiometry data were collected.

STUDY SAMPLE

125 infants were enrolled in the study; 67 completed audiological assessment, 62, 54, and 58 of whom attended ear screenings at 2-4, 6-8 and 12-18 months.

RESULTS

Of the children that attended the audiological assessment, 36.5%, 50% and 64.3% of infants had otitis media (OM) at 2-4, 6-8 and 12-18 months. Using a 10 dB correction factor, 44.8% of infants had hearing loss (HL) (≥ 25 dB HL) at ∼ 12 months of age. More males (X2=5.4 (1df, p = 0.02)) and infants with OM at audiological assessment (X2=5.8 (1df, p = 0.02)) had HL. More infants that used a pacifier at 12-18 months of age had HL (X2=4.7 (1df, p = 0.03)).

CONCLUSION

Aboriginal infants in an urban area have high rates of HL and OM, which requires early surveillance and timely treatment to reduce the medical and developmental impacts of OM and HL.

Cauchy combination omnibus test for normality

Testing whether data are from a normal distribution is a traditional problem and is of great concern for data analyses. The normality is the premise of many statistical methods, such as t-test, Hotelling T2 test and ANOVA. There are numerous tests in the literature and the commonly used ones are Anderson-Darling test, Shapiro-Wilk test and Jarque-Bera test. Each test has its own advantageous points since they are developed for specific patterns and there is no method that consistently performs optimally in all situations. Since the data distribution of practical problems can be complex and diverse, we propose a Cauchy Combination Omnibus Test (CCOT) that is robust and valid in most data cases. We also give some theoretical results to analyze the good properties of CCOT. Two obvious advantages of CCOT are that not only does CCOT have a display expression for calculating statistical significance, but extensive simulation results show its robustness regardless of the shape of distribution the data comes from. Applications to South African Heart Disease and Neonatal Hearing Impairment data further illustrate its practicability.

A Survey of U.S. Audiologists' Usage of and Attitudes Toward Otoacoustic Emissions

PURPOSE

Otoacoustic emissions (OAEs) provide information on outer hair cell function and have multiple clinical applications. Two types of OAEs, transient-evoked OAEs (TEOAEs) and distortion product OAEs (DPOAEs), are currently utilized in clinical practice. However, it remains unknown how confident U.S. clinicians are in performing and interpreting TEOAEs and DPOAEs. Additionally, the extent to which U.S. audiologists incorporate OAEs for different clinical applications and populations has not been thoroughly investigated. To fill these gaps in knowledge, this study characterized the attitudes toward and usage of TEOAEs and DPOAEs in a sample of U.S. audiologists.

METHOD

This study utilized an online survey distributed to U.S. audiologists through multiple channels from January to March 2021. A total of 214 completed surveys were included in the analysis. Results were analyzed descriptively. Associations between variables and comparisons between users of DPOAEs only and users of TEOAEs and DPOAEs were also examined.

RESULTS

DPOAEs were reportedly utilized more frequently and with greater confidence than TEOAEs. The most common clinical application of both OAE types was a cross-check. Significant associations were found between responses to DPOAE questions and the clinician's setting and patient age. There were some significant differences between users of DPOAEs only and users of TEOAEs and DPOAEs.

CONCLUSIONS

Results suggest that U.S. audiologists utilize OAEs for multiple clinical purposes and that there are appreciable differences in terms of attitudes toward and usage of DPOAEs versus TEOAEs. Future work could investigate the reasons that underlie these differences to further improve clinical implementation of OAEs.

Barriers to and Facilitators of Early Hearing Detection and Intervention in the United States: A Systematic Review

OBJECTIVES

Early hearing detection and intervention (EHDI) is guided by the 1-3-6 approach: screening by one month, diagnosis by 3 mo, and early intervention (EI) enrollment by 6 mo. Although screening rates remain high, successful diagnosis and EI-enrollment lag in comparison. The aim of this systematic review is to critically examine and synthesize the barriers to and facilitators of EHDI that exist for families, as they navigate the journey of congenital hearing loss diagnosis and management in the United States. Understanding barriers across each and all stages is necessary for EHDI stakeholders to develop and test novel approaches which will effectively reduce barriers to early hearing healthcare.

DESIGN

A systematic literature search was completed in May and August 2021 for empirical articles focusing on screening, diagnosis, and EI of children with hearing loss. Two independent reviewers completed title and abstract screening, full-text review, data extraction, and quality assessments with a third independent reviewer establishing consensus at each stage. Data synthesis was completed using the Framework Analysis approach to categorize articles into EHDI journey timepoints and individual/family-level factors versus system-level factors.

RESULTS

Sixty-two studies were included in the narrative synthesis. Results revealed that both individual/family-level (e.g., economic stability, medical status of the infant including middle ear involvement) and system-level barriers (e.g., system-service capacity, provider knowledge, and program quality) hinder timely diagnosis and EI for congenital hearing loss. Specific social determinants of health were noted as barriers to effective EHDI; however, system-level facilitators such as care coordination, colocation of services, and family support programs have been shown to mitigate the negative impact of those sociodemographic factors.

CONCLUSIONS

Many barriers exist for families to obtain appropriate and timely EHDI for their children, but system-level changes could facilitate the process and contribute to long-term outcomes improvement. Limitations of this study include limited generalizability due to the heterogeneity of EHDI programs and an inability to ascertain factor interactions.

National Infant Screening for Hearing Program in India: Necessity, Significance and Justification

Hearing impairment is one of the most prevalent disorder in children and adults worldwide, which not only interferes with the acquisition, development and maintenance of speech and language skills but also adversely deprive the auditory nervous system for future learning. It can have long term harmful effect on educational, social, emotional and cognitive skills in young children; restrict the vocational options and employment opportunities in adults; and can cause isolation, loneliness and depression in older adults, if remain undetected and intervened at the earliest. However, early identification and intervention is known to greatly reverse the ill effects and improve the quality of life of children and adults with hearing impairment. Current clinical means and methods to identify and intervene hearing loss are convenient, cost effective, reasonably accurate beneficial and evidenced based, can be easily employed nation-wide for early identification and intervention of hearing loss. This paper attempts to convince medical colleagues, public health care experts and policy makers by justifying the hearing, as public health issue and relevance of medical screening criteria for hearing. It also discusses the preferred model of hearing screening and intervention strategies in India.

Comparison of Otoacoustic Emission (OAE) and Brainstem Evoked Response Audiometry (BERA) in High Risk Infants and Children under 5 Years of Age for Hearing Assessment in Western India: A Modification in Screening Protocol

There are very few studies from India, which have compared Otoacoustic Emission (OAE) and Brainstem Evoked Response Audiometry (BERA) as a screening modality for detection of hearing loss in children. With the aim of establishing some guidelines regarding the protocols for hearing loss assessment and preventive measures, the present study has been undertaken to compare OAE with BERA done simultaneously, in the diagnosis of paediatric hearing loss, and also to study associated risk factors for hearing loss in children of Rural Central India. Prospective observational study was carried out on 100 children (200ears) in age group of 0-5 years. Selection was based on the inclusion and exclusion criteria. In all the 100 children detailed history was taken from the parents and were subjected to distortion product otoacoustic emissions (DPOAE). Irrespective of the pass or refer result children were subjected for BERA test. The interpretation of OAE and BERA test was as follows. Both the results of OAE refer and BERA fail were considered as confirmed HL, OAE pass and BERA fail were considered as children having Auditory Neuropathy (AN), OAE refer and BERA pass were considered as children at risk of permanent hearing loss (HL), OAE pass and BERA pass were considered as children with no evidence of HL. In the present study the male to female ratio was 1.32:1. Of the total 100 children 80% children showed presence of any one or more than one risk factors. In our study, eclampsia [7%] followed by multiparity [6%] and oligohydramnios [5%] were the most common risk factors in prenatal period. Maximum number of infants in AN profile were with Low Apgar score, children exposed to ototoxic medications, non-syndromic cardiac disorders in children [25.8% each]. Maximum number of infants in Confirmed HL profile were with congenital syndromes/ear anomalies [41.86%] followed by other risk factors. In our study, both OAE and BERA test were comparable and statistically significant with p value of 0.0001. OAE has a high specificity and positive predictive value of 93.33% and 97.22% respectively and it has a low sensitivity and negative predictive value of 67.74% and 45.65% respectively. In a developing country like India were universal screening protocols are not followed large number of children may be missed and may present late when it affects child's communication abilities. Hence, we need to modify our screening test and implement high risk screening even in the absence of any hearing or speech complaints.

Role of Otoacoustic Emission Test in Early Diagnosis of Hearing Impairment in Infants

Hearing impairment is most common congenital dissorder and undiagnosed hearing loss can cause disorder in speech, language with delay in social and emotional developments. Early detection of Hearing Impairment in Infants and too access the relationship between selected risk factor and hearing loss. Neonates age upto 15 days randomly selected from pediatric and obstetrics and gynaecology department, born during this period were screened by OAE before their discharge from the hospital and after stabilizing high risk neonates. Informed consent of neonates parent/guardian was obtained before babies were subjected to OAE. A total of 400 neonates were screened for hearing loss by otoacoustic emission. Out of that 18 (4.5%) neonates failed the test in initial screening and were asked for follow up screening. Two neonates were lost to follow up. Out of 16 neonates, 2 (12.5%) neonate failed the test on follow up screening by otoacoustic emission and was referred for BERA. Neonates were classified as low and high risk basis of risk factors present. Out of 76 neonates having high risk of hearing loss, 16 failed the test. Similarly out of 324 neonates with low risk of hearing loss, only one neonate failed the test. Chi square analysis has revealed highly significant results (p < 0.001). Late identification of hearing loss presents a significant public health concern. However, without screening, children with hearing loss are usually not identified until 2 years of age, which results in significant delays in voice communication, language communication, social, cognitive, and emotional development. In contrast, early recognition, and intervention prior to 3 months of historic period has a significant positive impact on development.

Audiologic characterization using clinical physiological measures: Normative data from macaque monkeys

Clinical auditory physiological measures (e.g., auditory brainstem responses, ABRs, and distortion product otoacoustic emissions, DPOAEs) provide diagnostic specificity for differentially diagnosing overt hearing impairments, but they remain limited in their ability to detect specific sites of lesion and subtle levels of cochlear damage. Studies in animal models may hold the key to improve differential diagnosis due to the ability to induce tightly controlled and histologically verifiable subclinical cochlear pathologies. Here, we present a normative set of traditional and clinically novel physiological measures using ABRs and DPOAEs measured in a large cohort of male macaque monkeys. Given the high similarities between macaque and human auditory anatomy, physiology, and susceptibility to hearing damage, this normative data set will serve as a crucial baseline to investigate novel physiological measures to improve diagnostics. DPOAE amplitudes were robust at f2 = 1.22, L1/L2 = 65/55, increased with frequency up to 10 kHz, and exhibited high test re-test reliability. DPOAE thresholds were lowest from 2-10 kHz and highest < 2 kHz. ABRs with a standard clinical electrode montage (vertex-to-mastoid, VM) produced Waves I-IV with a less frequently observed Wave-I, and lower thresholds. ABRs with a vertex-to-tympanic membrane (VT) electrode montage produced a more robust Wave-I, but absent Waves II-IV and higher thresholds. Further study with the VM montage revealed amplitudes that increased with stimulus level and were largest in response to click stimuli, with Wave-II showing the largest ABR amplitude, followed by -IV and -I, with high inter- and intra-subject variability. ABR wave latencies decreased with stimulus level and frequency. When stimulus presentation rate increased or stimuli were presented in close temporal proximity, ABR amplitude decreased, and latency increased. These findings expand upon existing literature of normative clinical physiological data in nonhuman primates and lay the groundwork for future studies investigating the effects of noise-induced pathologies in macaques.

Protocol and programme factors associated with referral and loss to follow-up from newborn hearing screening: a systematic review

Background

An effective newborn hearing screening programme has low referral rate and low loss to follow-up (LTFU) rate after referral from initial screening. This systematic review identified studies evaluating the effect of protocol and programme factors on these two outcomes, including the screening method used and the infant group.

Methods

Five databases were searched (latest: April 2021). Included studies reported original data from newborn hearing screening and described the target outcomes against a protocol or programme level factor. Studies were excluded if results were only available for one risk condition, for each ear, or for < 100 infants, or if methodological bias was observed. Included studies were evaluated for quality across three domains: sample, screening and outcome, using modified criteria from the Ottawa-Newcastle and QUADAS-2 scales. Findings from the included studies were synthesised in tables, figures and text.

Results

Fifty-eight studies reported on referral rate, 8 on LTFU rate, and 35 on both. Only 15 studies defined LTFU. Substantial diversity in referral and LTFU rate was observed across studies. Twelve of fourteen studies that evaluated screening method showed lower referral rates with aABR compared to TEOAE for well babies (WB). Rescreening before hospital discharge and screening after 3 days of age reduced referral rates. Studies investigating LTFU reported lower rates for programmes that had audiologist involvement, did not require fees for step 2, were embedded in a larger regional or national programme, and scheduled follow-up in a location accessible to the families. In programmes with low overall LTFU, higher LTFU was observed for infants from the NICU compared to WB.

Conclusion

Although poor reporting and exclusion of non-English articles may limit the generalisability from this review, key influential factors for referral and LTFU rates were identified. Including aABR in WB screening can effectively reduce referral rates, but it is not the only solution. The reported referral and LTFU rates vary largely across studies, implying the contribution of several parameters identified in this review and the context in which the programme is performed. Extra attention should be paid to infants with higher risk for hearing impairment to ensure their return to follow-up.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12887-022-03218-0.

AudioGene: refining the natural history of KCNQ4, GSDME, WFS1, and COCH-associated hearing loss

Autosomal dominant non-syndromic hearing loss (ADNSHL) displays gene-specific progression of hearing loss, which is amenable to sequential audioprofiling. We sought to refine the natural history of ADNSHL by examining audiometric data in 5-year increments. 2175 audiograms were included from four genetic causes of ADNSHL-KCNQ4 (DFNA2), GSDME (DFNA5), WFS1 (DFNA6/14/38), and COCH (DFNA9). Annual threshold deterioration (ATD) was calculated for each gene: for the speech-frequency pure tone average, the ATD, respectively, was 0.72 dB/year, 0.94 dB/year, 0.53 dB/year, and 1.41 dB/year, with the largest drops occurring from ages 45-50 (0.89 dB/year; KCNQ4), 5-10 (1.42 dB/year; GSDME), 40-45 (0.83 dB/year; WFS1), and 50-55 (2.09 dB/year; COCH). 5-year interval analysis of audiograms reveals the gene specific natural history of KCNQ4, GSDME, WFS1 and COCH-related progressive hearing loss. Identifying ages at which hearing loss is most rapid informs clinical care and patient expectations. Natural history data are also essential to define outcomes of clinical trials that test novel therapies designed to correct or ameliorate these genetic forms of hearing loss.

Nonparametric inference of the area under ROC curve under two-phase cluster sampling

Nonparametric inference of the area under ROC curve (AUC) has been well developed either in the presence of verification bias or clustering. However, current nonparametric methods are not able to handle cases where both verification bias and clustering are present. Such a case arises when a two-phase study design is applied to a cohort of subjects (verification bias) where each subject might have multiple test results (clustering). In such cases, the inference of AUC must account for both verification bias and intra-cluster correlation. In the present paper, we propose an IPW AUC estimator that corrects for verification bias and derive a variance formula to account for intra-cluster correlations between disease status and test results. Results of a simulation study indicate that the method that assumes independence underestimates the true variance of the IPW AUC estimator in the presence of intra-cluster correlations. The proposed method, on the other hand, provides a consistent variance estimate for the IPW AUC estimator by appropriately accounting for correlations between true disease statuses and between test results.

Detecting Hearing Loss in Infants With a Syndrome or Craniofacial Abnormalities Following the Newborn Hearing Screen

Purpose The current Joint Committee on Infant Hearing guidelines recommend that infants with syndromes or craniofacial abnormalities (CFAs) who pass the universal newborn hearing screening (UNHS) undergo audiological assessment by 9 months of age. However, emerging research suggests that children with these risk factors are at increased risk of early hearing loss despite passing UNHS. To establish whether earlier diagnostic audiological assessment is warranted for all infants with a syndrome or CFA, regardless of screening outcome, this study compared audiological outcomes of those who passed UNHS and those who referred. Method A retrospective analysis was performed on infants with a syndrome or CFA born between July 1, 2012, and June 30, 2017 who participated in Queensland, Australia's state-wide UNHS program. Results Permanent childhood hearing loss (PCHL) yield was higher among infants who referred on newborn hearing screening (51.20%) than in those who passed. Nonetheless, 27.47% of infants who passed were subsequently diagnosed with hearing loss (4.45% PCHL, 23.02% transient conductive), but PCHL was generally milder in this cohort. After microtia/atresia, the most common PCHL etiologies were Trisomy 21, other syndromes, and cleft palate. Of the other syndromes, Pierre Robin sequence featured prominently among infants who passed the hearing screen and were subsequently diagnosed with PCHL, whereas there was a broader mix of other syndromes that caused PCHL in infants who referred on screening. Conclusion Children identified with a syndrome or CFA benefit from early diagnostic audiological assessment, regardless of their newborn hearing screening outcome.

Minimal and Mild Hearing Loss in Children: Association with Auditory Perception, Cognition, and Communication Problems

OBJECTIVES

"Minimal" and "mild" hearing loss are the most common but least understood forms of hearing loss in children. Children with better ear hearing level as low as 30 dB HL have a global language impairment and, according to the World Health Organization, a "disabling level of hearing loss." We examined in a population of 6- to 11-year-olds how hearing level ≤40.0 dB HL (1 and 4 kHz pure-tone average, PTA, threshold) is related to auditory perception, cognition, and communication.

DESIGN

School children (n = 1638) were recruited in 4 centers across the United Kingdom. They completed a battery of hearing (audiometry, filter width, temporal envelope, speech-in-noise) and cognitive (IQ, attention, verbal memory, receptive language, reading) tests. Caregivers assessed their children's communication and listening skills. Children included in this study (702 male; 752 female) had 4 reliable tone thresholds (1, 4 kHz each ear), and no caregiver reported medical or intellectual disorder. Normal-hearing children (n = 1124, 77.1%) had all 4 thresholds and PTA <15 dB HL. Children with ≥15 dB HL for at least 1 threshold, and PTA <20 dB (n = 245, 16.8%) had minimal hearing loss. Children with 20 ≤PTA <40 dB HL (n = 88, 6.0%) had mild hearing loss. Interaural asymmetric hearing loss ( left PTA - right PTA ≥10 dB) was found in 28.9% of those with minimal and 39.8% of those with mild hearing loss.

RESULTS

Speech perception in noise, indexed by vowel-consonant-vowel pseudoword repetition in speech-modulated noise, was impaired in children with minimal and mild hearing loss, relative to normal-hearing children. Effect size was largest (d = 0.63) in asymmetric mild hearing loss and smallest (d = 0.21) in symmetric minimal hearing loss. Spectral (filter width) and temporal (backward masking) perceptions were impaired in children with both forms of hearing loss, but suprathreshold perception generally related only weakly to PTA. Speech-in-noise (nonsense syllables) and language (pseudoword repetition) were also impaired in both forms of hearing loss and correlated more strongly with PTA. Children with mild hearing loss were additionally impaired in working memory (digit span) and reading, and generally performed more poorly than those with minimal loss. Asymmetric hearing loss produced as much impairment overall on both auditory and cognitive tasks as symmetric hearing loss. Nonverbal IQ, attention, and caregiver-rated listening and communication were not significantly impaired in children with hearing loss. Modeling suggested that 15 dB HL is objectively an appropriate lower audibility limit for diagnosis of hearing loss.

CONCLUSIONS

Hearing loss between 15 and 30 dB PTA is, at ~20%, much more prevalent in 6- to 11-year-old children than most current estimates. Key aspects of auditory and cognitive skills are impaired in both symmetric and asymmetric minimal and mild hearing loss. Hearing loss <30 dB HL is most closely related to speech perception in noise, and to cognitive abilities underpinning language and reading. The results suggest wider use of speech-in-noise measures to diagnose and assess management of hearing loss and reduction of the clinical hearing loss threshold for children to 15 dB HL.

A ROC-based test for evaluating the group difference with an application to neonatal audiology screening

This article proposes a powerful method to compare two samples. The proposed method handles comparison of data by drawing inference from ROC curve model parameters. The method estimates parameters from a linear model framework on the empirical sensitivities and specificities. The consistent ROC parameters are then used to give a more powerful test than existing methods in several situations. In addition, we present a comprehensive statistic based on the Cauchy combination, which works well in all scenarios considered in this article. We also offer an efficient one-layer wild permutation procedure to calculate the P-value of our statistic. The method is particularly useful when the underlying continuous biomarker results are non-normal. We illustrate the proposed methods in a neonatal audiology diagnostic example.

Effect of delivery mode on neonate auditory brainstem responses to air- and bone-conducted stimuli

OBJECTIVES

The object of this study was to examine if caesarean section delivered neonates have different middle ear function relative to neonates with vaginal delivery.

METHODS

Auditory brainstem responses (ABRs) were examined in caesarean section delivered (n = 23) and vaginally delivered (n = 29) neonates. ABRs were also evoked with air- and bone-conducted stimuli (i.e., clicks and CE-Chirps) and presented at a screening intensity level (i.e., 30 dB nHL). Wave V latencies and amplitudes were examined as a function of mode of delivery and stimuli.

RESULTS

Statistically significant longer wave V latencies evoked with air-conducted stimuli were seen in caesarean section delivered neonates (p = .042). There was no statistically significant difference in wave V latencies with bone-conducted stimuli among the two groups of neonates (p = .42). There were no significant differences in wave V amplitude between neonates with caesarean section and vaginal delivery for air-conducted (p = .42) stimuli. Wave V amplitudes were not significantly different as a function of mode of delivery with CE-Chirp stimulus (p = .41). Wave V amplitudes were significantly larger for the caesarean section delivered neonates with the bone-conducted click stimulus (p = .036).

CONCLUSIONS

The ABR wave V latency disparity with air- and bone-conducted stimuli support the notion that differences in middle ear function exist between the two groups of newborns. It was speculated that delayed fluid resorption in the middle ear exists in neonates with caesarean section delivery compared to those with vaginal delivery.

A Preliminary Study on the Safety of Elastography during Pregnancy: Hypoacusia, Anthropometry, and Apgar Score in Newborns

Transient or acoustic radiation force elastography (ARFE) is becoming the most extended technology to assess cervical effacement, additionally to the Bishop test and conventional ultrasound. However, a debate on the fetal safety has been opened due to the high intensity focused beam emitted to produce shear waves. This work is aimed at providing preliminary data to assess clinical effects of fetal exposure. A follow-up study in newborns of 42 women exposed to ARFE during pregnancy was carried out to explore neonatal hypoacusia, Apgar test, and anthropometry. No hypoacusia cases attributable to ARFE were observed. The Apgar test at five minutes scored normally in all the newborns. Comparisons between anthropometric measurements showed no significant statistically differences. The results preclude to state the harmfulness nor the safety of ARFE. However, given the concern on the high level of energy and the potential risk of harmful bioeffects, larger studies are recommended.

Comparisons of Auditory Brainstem Responses Between a Laboratory and Simulated Home Environment

Purpose Miniaturization of digital technologies has created new opportunities for remote health care and neuroscientific fieldwork. The current study assesses comparisons between in-home auditory brainstem response (ABR) recordings and recordings obtained in a traditional lab setting. Method Click-evoked and speech-evoked ABRs were recorded in 12 normal-hearing, young adult participants over three test sessions in (a) a shielded sound booth within a research lab, (b) a simulated home environment, and (c) the research lab once more. The same single-family house was used for all home testing. Results Analyses of ABR latencies, a common clinical metric, showed high repeatability between the home and lab environments across both the click-evoked and speech-evoked ABRs. Like ABR latencies, response consistency and signal-to-noise ratio (SNR) were robust both in the lab and in the home and did not show significant differences between locations, although variability between the home and lab was higher than latencies, with two participants influencing this lower repeatability between locations. Response consistency and SNR also patterned together, with a trend for higher SNRs to pair with more consistent responses in both the home and lab environments. Conclusions Our findings demonstrate the feasibility of obtaining high-quality ABR recordings within a simulated home environment that closely approximate those recorded in a more traditional recording environment. This line of work may open doors to greater accessibility to underserved clinical and research populations.

A clinical comparison of DPOAE fine structure reduction methods

OBJECTIVE

To evaluate two real-time methods for reducing distortion product otoacoustic emission (DPOAE) fine structure in terms of DPOAE amplitude and fine structure depth.

DESIGN

A prospective, repeated-measures design was used to assess DPOAE characteristics in response to a conventional stimulation method (Conv.), as well as for methods implementing either a generic suppressor tone (Supp.) or frequency modulation of the f₂ primary tone (FM).

STUDY SAMPLE

Eighty-three young adults (58 females) between the ages of 20 and 34 years with normal hearing completed testing for this study.

RESULTS

Use of the Conv. and FM methods resulted in consistently higher DPOAE levels relative to the Supp. method, with average advantages of 6 and 5 dB, respectively. For all methods, increased fine structure depth was observed for stimulation with lower level (25-45 dB SPL) and lower frequency (1000-3000 Hz) primary tones. Finally, use of the Supp. and FM methods resulted in significantly decreased fine structure depth relative to the Conv. method.

CONCLUSION

Through frequency modulation of the f₂ primary tone, it was possible to reduce the depth of fine structure across a clinically meaningful range of stimulation levels and frequencies without concomitant reduction in DPOAE amplitude.

Estimating Hearing Thresholds From Stimulus-Frequency Otoacoustic Emissions

It is of clinical interest to estimate pure-tone thresholds from potentially available objective measures, such as stimulus-frequency otoacoustic emissions (SFOAEs). SFOAEs can determine hearing status (normal hearing vs. hearing loss), but few studies have explored their further potential in predicting audiometric thresholds. The current study investigates the ability of SFOAEs to predict hearing thresholds at octave frequencies from 0.5 to 8 kHz. SFOAE input/output functions and pure-tone thresholds were measured from 230 ears with normal hearing and 737 ears with sensorineural hearing loss. Two methods were used to predict hearing thresholds. Method 1 is a linear regression model; Method 2 proposed in this study is a back propagation (BP) network predictor built on the bases of a BP neural network and principal component analysis. In addition, a BP network classifier was built to identify hearing status. Both Methods 1 and 2 were able to predict hearing thresholds from 0.5 to 8 kHz, but Method 2 achieved better performance than Method 1. The BP network classifiers achieved excellent performance in determining the presence or absence of hearing loss at all test frequencies. The results show that SFOAEs are not only able to identify hearing status with great accuracy at all test frequencies but, more importantly, can predict hearing thresholds at octave frequencies from 0.5 to 8 kHz, with best performance at 0.5 to 4 kHz. The BP network predictor is a potential tool for quantitatively predicting hearing thresholds, at least at 0.5 to 4 kHz.

Concurrent hearing and genetic screening in a general newborn population

Newborn hearing screening is not designed to detect delayed-onset prelingual hearing loss or aminoglycoside-antibiotic-induced ototoxicity. Cases with severe to profound hearing loss have been reported to have been missed by newborn hearing screens. The aim of this study was to evaluate the efficacy of concurrent hearing and genetic screening in the general population and demonstrate its benefits in practice. Enrolled newborns received concurrent hearing and genetic screens between September 1, 2015 and January 31, 2018. Of the 239,636 eligible infants (median age, 19 months), 548 (0.23%) had prelingual hearing loss. Genetic screening identified 14 hearing loss patients with positive genotypes and 27 patients with inconclusive genotypes who had passed the hearing screens. In addition, the genetic screen identified 0.23% (570/239,636) of the newborns and their family members as at-risk for ototoxicity, which is undetectable by hearing screens. In conclusion, genetic screening complements newborn hearing screening by improving the detection of infants at risk of hereditary hearing loss and ototoxicity, and by informing genotype-based clinical management for affected infants and their family members. Our findings suggest that the practice should be further validated in other populations and rigorous cost-effectiveness analyses are warranted.

Audibility-Based Hearing Aid Fitting Criteria for Children With Mild Bilateral Hearing Loss

Purpose Because of uncertainty about the level of hearing where hearing aids should be provided to children, the goal of the current study was to develop audibility-based hearing aid candidacy criteria based on the relationship between unaided hearing and language outcomes in a group of children with hearing loss who did not wear hearing aids. Method Unaided hearing and language outcomes were examined for 52 children with mild-to-severe hearing losses. A group of 52 children with typical hearing matched for age, nonverbal intelligence, and socioeconomic status was included as a comparison group representing the range of optimal language outcomes. Two audibility-based criteria were considered: (a) the level of unaided hearing where unaided children with hearing loss fell below the median for children with typical hearing and (b) the level of unaided hearing where the slope of language outcomes changed significantly based on an iterative, piecewise regression modeling approach. Results The level of unaided audibility for children with hearing loss that was associated with differences in language development from children with typical hearing or based on the modeling approach varied across outcomes and criteria but converged at an unaided speech intelligibility index of 80. Conclusions Children with hearing loss who have unaided speech intelligibility index values less than 80 may be at risk for delays in language development without hearing aids. The unaided speech intelligibility index potentially could be used as a clinical criterion for hearing aid fitting candidacy for children with hearing loss.

Newborn Hearing Screening: Early Education = More Satisfied Mothers

Newborn hearing screening (NBHS) has become the norm in all states in the United States. However, parents receive limited information about it, usually at the hospital, and have low awareness about the process. Yet parents and professionals agree that communication about the NBHS process should begin before childbirth (Arnold et al., 2006). Having information about the screening process, simply by being present for the screening and knowing the results, has been shown to positively affect parental attitudes toward NBHS (Weichbold, Welzl-Mueller, & Mussbacher, 2001). Purpose The aim of this study was to assess whether providing expectant mothers with information related to the NBHS process in the 3rd trimester will increase their satisfaction with the NBHS program. Method Partnering with a local obstetrician, expectant mothers were provided with information regarding NBHS. A modified version of the Parent Satisfaction Questionnaire with Neonatal Hearing Screening Program (Mazlan, Hickson, & Driscoll, 2006) was administered to mothers who received information and mothers who did not receive any education. Results Quantitative results indicate significantly increased satisfaction with the NBHS program when early education was received. Qualitative comments from participants support the quantitative findings. Conclusion Results suggest that educating obstetricians and their nurses about NBHS and having them provide information to expectant mothers, as well as having mothers present for the screening, may increase parental satisfaction and therefore benefit early hearing detection and intervention programs.

Cochlear Mechanisms and Otoacoustic Emission Test Performance

OBJECTIVES

This study aims to determine the impact of controlling cochlear-source mechanism on the accuracy with which auditory status is identified using otoacoustic emissions (OAEs) in two groups of subjects with normal hearing (NH) and subjects with mild to moderate hearing loss.

DESIGN

Data were collected from 212 subjects with NH and with mild to moderate hearing loss who fell into two categories based on a distortion product OAE (DPOAE) screening protocol: the uncertain-identification group (where errors were likely) and the certain-identification group (where errors were unlikely). DPOAE fine-structure patterns were recorded at intervals surrounding f2 = 1, 2 and 4 kHz (f2/f1 ratio = 1.22), with L2 = 35, 45, and 55 dB SPL (L1/L2 ratio = 10 dB). The discrete cosine transform was used to smooth fine structure, limiting the source contribution to the distortion source only. Reflection-source OAEs were also recorded using amplitude-modulated stimulus frequency OAEs (AM-SFOAE). Area under the relative operating characteristic (AROC) curve was used to quantify test accuracy when the source contribution was controlled versus the condition where both sources contribute. Additionally, failure rate, fixed at 5% for NH ears, as a function of behavioral-threshold category was evaluated.

RESULTS

When data for the entire subject group were examined, reducing the reflection-source contribution to the DPOAE did not result in better test performance than the best control condition at any frequency tested. When the subjects with NH were restricted to those with confirmed fine structure, AROC analyses indicated that reducing the reflection-source contribution resulted in several small increases in the accuracy (2%-5%) with which auditory status was identified relative to the best control condition. This improvement was observed for the lowest stimulus levels (i.e., L2 = 35 or 45 dB SPL). In this subset of subjects, distortion-source DPOAEs resulted in more accurate identification of mild hearing loss for a fixed false-positive rate of 5% in NH ears at lower L2's, conditions with poor accuracy in the larger group of subjects. The impact of controlling the source contribution on the identification of moderate losses was less clear in the reduced subject group, with some conditions where the distortion-source DPOAE was more accurate than the control condition and other conditions where there was no change. There was no evidence that reflection-source AM-SFOAEs more accurately identified ears with hearing loss when compared to any of the DPOAE conditions in either the large or reduced group of subjects.

CONCLUSION

While improvements in test accuracy were observed for some subjects and some conditions (e.g., mild hearing losses and low stimulus levels in the reduced subset of subjects), these results suggest that restricting cochlear source contribution by "smoothing" DPOAE fine structure is not expected to improve DPOAE test accuracy in a general population of subjects. Likewise, recording reflection-source OAEs using the AM-SFOAE technique would not be expected to more accurately identify hearing status compared to mixed- or single-source DPOAEs.

Genetic screening as an adjunct to universal newborn hearing screening: literature review and implications for non-congenital pre-lingual hearing loss

Objective: Universal newborn hearing screening (UNHS) uses otoacoustic emissions testing (OAE) and auditory brainstem response testing (ABR) to screen all newborn infants for hearing loss (HL), but may not identify infants with mild HL at birth or delayed onset HL. The purpose of this review is to examine the role of genetic screening to diagnose children with pre-lingual HL that is not detected at birth by determining the rate of children who pass UNHS but have a positive genetic screening. This includes a summary of the current UNHS and its limitations and a review of genetic mutations and screening technologies used to detect patients with an increased risk of undiagnosed pre-lingual HL.Design: Literature review of studies that compare UNHS with concurrent genetic screening.Study sample: Infants and children with HLResults: Sixteen studies were included encompassing 137,895 infants. Pathogenic mutations were detected in 8.66% of patients. In total, 545 patients passed the UNHS but had a positive genetic screening. The average percentage of patients who passed UNHS but had a positive genetic screening was 1.4%.Conclusions: This review demonstrates the positive impact of concurrent genetic screening with UNHS to identify patients with pre-lingual HL.

Optimizing Clinical Interpretation of Distortion Product Otoacoustic Emissions in Infants

OBJECTIVES

The purpose of this study was to analyze distortion product otoacoustic emission (DPOAE) level and signal to noise ratio in a group of infants from birth to 4 months of age to optimize prediction of hearing status. DPOAEs from infants with normal hearing (NH) and hearing loss (HL) were used to predict the presence of conductive HL (CHL), sensorineural HL (SNHL), and mixed HL (MHL). Wideband ambient absorbance was also measured and compared among the HL types.

DESIGN

This is a prospective, longitudinal study of 279 infants with verified NH and HL, including conductive, sensorineural, and mixed types that were enrolled from a well-baby nursery and two neonatal intensive care units in Cincinnati, Ohio. At approximately 1 month of age, DPOAEs (1-8 kHz), wideband absorbance (0.25-8 kHz), and air and bone conduction diagnostic tone burst auditory brainstem response (0.5-4 kHz) thresholds were measured. Hearing status was verified at approximately 9 months of age with visual reinforcement audiometry (0.5-4 kHz). Auditory brainstem response air conduction thresholds were used to assign infants to an NH or HL group, and the efficacy of DPOAE data to classify ears as NH or HL was analyzed using receiver operating characteristic (ROC) curves. Two summary statistics of the ROC curve were calculated: the area under the ROC curve and the point of symmetry on the curve at which the sensitivity and specificity were equal. DPOAE level and signal to noise ratio cutoff values were defined at each frequency as the symmetry point on their respective ROC curve, and DPOAE results were combined across frequency in a multifrequency analysis to predict the presence of HL.

RESULTS

Single-frequency test performance of DPOAEs was best at mid to high frequencies (3-8 kHz) with intermediate performance at 1.5 and 2 kHz and chance performance at 1 kHz. Infants with a conductive component to their HL (CHL and MHL combined) displayed significantly lower ambient absorbance values than the NH group. No differences in ambient absorbance were found between the NH and SNHL groups. Multifrequency analysis resulted in the best prediction of HL for the SNHL/MHL group with poorer sensitivity values when infants with CHL were included.

CONCLUSIONS

Clinical interpretation of DPOAEs in infants can be improved by using age-appropriate normative ranges and optimized cutoff values. DPOAE interpretation is most predictive at higher F2 test frequencies in young infants (2-8 kHz) due to poor test performance at 1 to 1.5 kHz. Multifrequency rules can be used to improve sensitivity while balancing specificity. Last, a sensitive middle ear measure such as wideband absorbance should be included in the test battery to assess possibility of a conductive component to the HL.

International consensus (ICON) on audiological assessment of hearing loss in children

The prevalence of hearing loss in newborns and infants is estimated between 1 to 3.47 cases per 1000 live births. Early diagnosis and rehabilitation of congenital hearing loss are mandatory in order to achieve a satisfactory linguistic and cognitive development. Without appropriate opportunities to learn language, these children will fall behind their normal hearing peers in communication, cognition, reading and socio-emotional development. After promising results, neonatal screening for hearing loss and audiological evaluation are becoming more extensively carried out. In planning universal neonatal hearing screening programs, transient evoked otoacoustic emissions and auditory brainstem responses are the gold standard for the screening and diagnosis program. However, there is no consensus regarding the use of audiometry and other electrophysiological tests (such as auditory steady-state responses) in current practices. Several screening and audiological assessment procedures have been described and advocated all around the world. But, a systematic scheme of performing diagnosis in the pediatric audiology population is lacking. A consensus conference was held at the International Federation of Oto-rhino-laryngological Societies Congress, in June 2017, to discuss the different current practices and to identify the best neonatal hearing screening and audiological assessment management. This article is intended to provide professionals with recommendations about the "best practice" based on consensus opinion of the session's speakers, and a review of the literature on the efficacy of various assessment options for children with hearing loss.

Universal newborn hearing screening using A-TEOAE and A-ABR: The experience of a large public hospital

BACKGROUND

Universal newborn hearing screening (UNHS) aims to identify hearing loss in the early postnatal period; prompt detection of bilateral or unilateral hearing loss is mandatory for timely intervention.

METHODS

This retrospective study reports the results of the first two years of a UNHS program on 4,719 newborns in a large public Italian hospital. Screening was divided into two levels: automated transient otoacoustic emissions were used for first level; automated auditory brainstem response for second level. Second level included children with a "refer" response at first level and babies with a family history for hearing loss or other risk factors. Hearing loss diagnosis was made using clinical auditory brainstem response.

RESULTS

During first level, 254 (5.4% ) newborns were "refer". At retest, 130 (51.1% ) babies were PASS and 48 (18.8% ) were "refer". 76 babies dropped out (29.9% ). 146 babies (3.1% ) were referred to the second level: 48 for a "refer" response at first level and 98 for a PASS response but potential hearing loss due to risk factors. 24 babies dropped out (16.4% ). Out of 122 newborns tested in the second level, 105 (86.1% ) had a PASS response and 17 (13.9% ) were "refer". Our screening protocol identified 7 (0.14% ) babies with profound hearing loss; 5 had unilateral and 2 had bilateral hearing loss. 2 babies dropped out at diagnostic level (11.8% ).

CONCLUSIONS

A correct and early diagnosis of hearing loss is mandatory to prevent permanent consequences; the spread of hearing screening programs is the optimal solution to reach this goal.

Current audiological diagnostics

Today's audiological functional diagnostics is based on a variety of hearing tests, whose large number takes account of the variety of malfunctions of a complex sensory organ system and the necessity to examine it in a differentiated manner and at any age of life. The objective is to identify nature and origin of the hearing loss and to quantify its extent as far as necessary to dispose of the information needed to initiate the adequate medical (conservative or operational) treatment or the provision with technical hearing aids or prostheses. Moreover, audiometry provides the basis for the assessment of impairment and handicap as well as for the calculation of the degree of disability. In the present overview, the current state of the method inventory available for practical use is described, starting from basic diagnostics over to complex special techniques. The presentation is systematically grouped in subjective procedures, based on psychoacoustic exploration, and objective methods, based on physical measurements: preliminary hearing tests, pure tone threshold, suprathreshold processing of sound intensity, directional hearing, speech understanding in quiet and in noise, dichotic hearing, tympanogram, acoustic reflex, otoacoustic emissions and auditory evoked potentials. Apart from a few still existing gaps, this method inventory covers the whole spectrum of all clinically relevant functional deficits of the auditory system.

Hearing impairment in premature newborns-Analysis based on the national hearing screening database in Poland

Objectives

The incidence of sensorineural hearing loss is between 1 and 3 per 1000 in healthy neonates and 2–4 per 100 in high-risk infants. The national universal neonatal hearing screening carried out in Poland since 2002 enables selection of infants with suspicion and/or risk factors of hearing loss. In this study, we assessed the incidence and risk factors of hearing impairment in infants ≤33 weeks’ gestational age (wga).

Methods

We analyzed the database of the Polish Universal Newborns Hearing Screening Program from 2010 to 2013. The study group involved 11438 infants born before 33 wga, the control group—1487730 infants. Screening was performed by means of transient evoked otoacoustic emissions. The risk factors of hearing loss were recorded. Infants who failed the screening test and/or had risk factors were referred for further audiological evaluation.

Results

Hearing deficit was diagnosed in 11% of infants ≤25 wga, 5% at 26–27 wga, 3.46% at 28 wga and 2–3% at 29–32 wga. In the control group the incidence of hearing deficit was 0.2% (2.87% with risk factors). The most important risk factors were craniofacial malformations, very low birth weight, low Apgar score and mechanical ventilation. Hearing screening was positive in 22.42% newborns ≤28 wga and 10% at 29–32 wga and in the control group.

Conclusions

Hearing impairment is a severe consequence of prematurity. Its prevalence is inversely related to the maturity of the baby. Premature infants have many concomitant risk factors which influence the occurrence of hearing deficit.

Hearing status in patients with rheumatoid arthritis

Objective:

Rheumatoid arthritis is thought to induce conductive hearing loss and/or sensorineural hearing loss. This study evaluated the function of the middle ear and cochlea, and the related factors.

Methods:

Pure tone audiometry, speech reception thresholds, speech discrimination scores, tympanometry, acoustic reflexes, and distortion product otoacoustic emissions were assessed in rheumatoid arthritis patients and healthy volunteers.

Results:

Pure tone audiometry results revealed a higher bone conduction threshold in the rheumatoid arthritis group, but there was no significant difference when evaluated according to the sensorineural hearing loss definition. Distortion product otoacoustic emissions related prevalence of conductive or mixed hearing loss, tympanometry values, acoustic reflexes, and speech discrimination scores were not significantly different between the two groups. Sensorineural hearing loss was significantly more prevalent in patients who used azathioprine, cyclosporine and etanercept.

Conclusion:

Higher bone conduction thresholds in some frequencies were detected in rheumatoid arthritis patients that were not clinically significant. Sensorineural hearing loss is significantly more prevalent in refractory rheumatoid arthritis patients.

Monitoring neonates for ototoxicity

OBJECTIVES

Neonates admitted to the neonatal intensive care unit (NICU) are at greater risk of permanent hearing loss compared to infants in well mother and baby units. Several factors have been associated with this increased prevalence of hearing loss, including congenital infections (e.g. cytomegalovirus or syphilis), ototoxic drugs (such as aminoglycoside or glycopeptide antibiotics), low birth weight, hypoxia and length of stay. The aetiology of this increased prevalence of hearing loss remains poorly understood.

DESIGN

Here we review current practice and discuss the feasibility of designing improved ototoxicity screening and monitoring protocols to better identify acquired, drug-induced hearing loss in NICU neonates.

STUDY SAMPLE

A review of published literature.

CONCLUSIONS

We conclude that current audiological screening or monitoring protocols for neonates are not designed to adequately detect early onset of ototoxicity. This paper offers a detailed review of evidence-based research, and offers recommendations for developing and implementing an ototoxicity monitoring protocol for young infants, before and after discharge from the hospital.

Parent educational materials regarding the newborn hearing screening process

PURPOSE

Newborn hearing screening (NHS) procedures and implementation vary from state to state in the US. The purpose of this study was to evaluate the content and nature of information provided to parents about their infant's NHS across states to answer two questions: 1) what information is included in each state's parent information brochure? and 2) do the brochures include educational information requested by parents that may help reduce parental anxiety, improve satisfaction, and decrease the potential for misunderstandings?

METHOD

Each state's parent brochures and educational resources provided to parents were accessed via the National Center for Hearing Assessment and Management (NCHAM) website, categorized, and reviewed for content.

RESULTS

Results indicate that the information provided to parents varies considerably across states and many brochures do not contain important information that is desired by parents.

CONCLUSIONS

NHS procedures may be improved by providing standardized information regarding the process to parents in all states.

Universal newborn hearing screening: methods and results, obstacles, and benefits

The incidence of sensorineural hearing loss ranges from 1 to 3 per 1,000 live births in term healthy neonates, and 2-4 per 100 in high-risk infants, a 10-fold increase. Early identification and intervention with hearing augmentation within 6 mo yields optimal effect. If undetected and without treatment, significant hearing impairment may negatively impact speech development and lead to disorders in psychological and mental behaviors. Hearing screening programs in newborns enable detection of hearing impairment in the first days after birth. Programs to identify hearing deficit have significantly improved over the two decades, and their implementation continues to grow throughout the world. Initially based on risk factors, these programs identified only 50-75% of infants with hearing loss. Current recommendations are to conduct universal hearing screening in all infants. Techniques used primarily include automated auditory brainstem responses and otoacoustic emissions that provide noninvasive recordings of physiologic auditory activity and are easily performed in neonates and infants. The aim of this review is to present the objectives, benefits, and results of newborn hearing screening programs including the pros and cons of universal vs. selective screening. A brief history and the anticipated future development of these programs will also be discussed.

Congenital hearing loss

Congenital hearing loss (hearing loss that is present at birth) is one of the most prevalent chronic conditions in children. In the majority of developed countries, neonatal hearing screening programmes enable early detection; early intervention will prevent delays in speech and language development and has long-lasting beneficial effects on social and emotional development and quality of life. A diagnosis of hearing loss is usually followed by a search for an underlying aetiology. Congenital hearing loss might be attributed to environmental and prenatal factors, which prevail in low-income settings; congenital infections, particularly cytomegalovirus infection, are also a common risk factor for hearing loss. Genetic causes probably account for the majority of cases in developed countries; mutations can affect any component of the hearing pathway, in particular, inner ear homeostasis (endolymph production and maintenance) and mechano-electrical transduction (the conversion of a mechanical stimulus into electrochemical activity). Once the underlying cause of hearing loss is established, it might direct therapeutic decision making and guide prevention and (genetic) counselling. Management options include specific antimicrobial therapies, surgical treatment of craniofacial abnormalities and implantable or non-implantable hearing devices. An improved understanding of the pathophysiology and molecular mechanisms that underlie hearing loss and increased awareness of recent advances in genetic testing will promote the development of new treatment and screening strategies.

Follow-up in newborn hearing screening - A systematic review

INTRODUCTION

The quality and efficiency of newborn hearing screening programs (NHS) rely heavily on appropriate follow-up. The Joint Committee on Infant Hearing recommends a follow-up rate of more than 95% of infants who fail the initial hearing screening. However, a 70% benchmark is considered to be more feasible. This high loss to follow-up (LTF) rate acts as a threat to the overall success of NHS programs. The objective of the study was to identify and examine the reported rates of LTF, attributed reasons for LTF and strategies undertaken to reduce LTF.

METHODS

Using a systematic search, articles published between 2005 to December 2015 were identified from PubMed/Medline, Cumulative Index to Nursing and Allied Health Literature (CINAHL), Educational Resources Information Center (ERIC), Scopus, Ovid, ProQuest, and Cochrane Library. To be included in the review, the study should be exploring the loss to follow-up or drop-out rate in newborn hearing screening programs and be published in an indexed peer-reviewed journal in the English language. The main outcome measures were overall rate of LTF, factors leading to LTF and measures adopted to overcome LTF.

RESULTS

53 articles were short-listed for data extraction. Out of these, 27 were single-centre studies, 19 were multi-centre, 3 compared multiple databases, and 4 used survey-based methods. Overall LTF rates of 20% in single-centre and 21% in multiple-centre studies were observed. Educational disparity and lack of adequate knowledge among parents were associated with LTF. The most commonly used strategy to overcome LTF suggested by studies was the use of an adequate data management system.

CONCLUSION

This review is a novel attempt to explore the LTF among NHS studies, reasons for LTF and strategies to reduce LTF. This review can act as a basis for planning and execution of effective NHS programs.

The assessment of the Newborn Hearing Screening Program in the Region of Murcia from 2004 to 2012

OBJECTIVES

Newborn (NB) auditory deficit has a prevalence of 1-2% in the world. Since the 1990s different screening programs have been put into practice. The Newborn Hearing Screening Program has been in operation since 2002 in our hospital (HCUVA) in Murcia (Spain) and two years later it was introduced into the whole of the Autonomous Community of the Region of Murcia as part of universal healthcare. The objective of this study was to analyze and assess its results.

METHOD

The newborn (NB) population is divided into two groups: not-at-risk NBs and at-risk NBs. In the first case we carry out acoustic otoemissions (AOEs) 48 h after birth and depending on the result the child is either discharged or, in negative cases, the infant undergoes a series of tests in a period of 30-45 days to confirm or rule out the existence of hearing anomalies. In the at-risk group we combine AOEs with brain trunk potentials (BERA) following the stages in a decision tree diagram similar to the ones for not-at-risk children in order to provide a clinical diagnosis in the first three months of life.

RESULTS

The screening performance was assessed for the 156,122 children studied, of which 151,258 belonged to the group of not-at-risk children; and 4864 to the group at risk of hypoacusia. As a result of the screening only 410 (0.26%) were sent to consultation, 213 in the not-at-risk group (0.14%) and 197 (24.7%) in the at-risk group. A total of 7452 false positives were identified (4.7%), 6951 (4.5%) in the not-at-risk group; and 501 (10.3%) in the group with risk factors; and there were 53 false negatives (0.03%). Sensitivity in the screening program was 88.5%, with a specificity of 95%.

CONCLUSIONS

The Region of Murcia has a Newborn Hearing Screening Program with tests that provide a high level of sensitivity and specificity in accordance with the findings of the literature. Our results endorse the program and the patients were treated in a way that met the objective of providing a correct diagnosis and the appropriate therapeutic action.

Comparação de dois protocolos de triagem auditiva neonatal com critérios de referência de passa e falha distintos

RESUMO Objetivo: comparar dois protocolos de triagem auditiva neonatal com critérios de referência de passa e falha distintos. Métodos: estudo retrospectivo. Foram avaliados os prontuários de 312 indivíduos, entre eles, RN(s) e bebês de ambos os sexos com até 90 dias de nascidos, sendo de baixo e alto risco para a deficiência auditiva, no período de setembro de 2013 a setembro de 2014 no Serviço de Triagem Auditiva Neonatal da Clínica Escola da instituição de origem. Os prontuários consultados referem-se a RN(s) ou bebês submetidos à triagem auditiva neonatal por meio das Emissões Otoacústicas Evocadas Transientes (EOAT). As EOAT foram analisadas considerando tanto o critério de referência proposto por FINITZO (1998) (PROTOCOLO 1) quanto os critérios de referência vindos de fábrica no equipamento (PROTOCOLO 2), e os mesmos foram comparados. Foi realizada uma análise descritiva para caracterização da amostra. Resultados: dos 312 indivíduos avaliados, observou-se maior número do sexo masculino (53,85%), a maioria tinha 30 dias ou menos (65,06%) e somente 6,09% tinham mais de 60 dias. A proporção de concordância observada foi de 43,91% e o índice de Kappa foi de 0,0628, com o intervalo de confiança de 95% de (0,03; 0,0942) e uma significância estatística de 0,001 (p=0,001). Observa-se que o valor do Kappa é bem baixo, considerando que a concordância perfeita é de 1,00. Conclusão: não houve concordância estatística entre os protocolos analisados, houve mais falhas na etapa da TAN pelo critério de referência do protocolo 1.

Feasibility of newborn hearing screening in a public hospital setting in South Africa: A pilot study

Objectives

The current pilot study aimed to explore the feasibility of newborn hearing screening (NHS) in a hospital setting with clinical significance for the implementation of NHS. Context-specific objectives included determining the average time required to screen each neonate or infant; the most suitable time for initial hearing screening in the wards; as well as the ambient noise levels in the wards and at the neonatal follow-up clinic where screening would be conducted.

Method

A descriptive, longitudinal, repeated measures, within-subjects design was employed. The pilot study comprised 11 participants who underwent hearing screening. Data were analysed using descriptive statistics.

Results

The average time taken to conduct hearing screening using otoacoustic emissions and automated auditory brainstem response was 18.4 minutes, with transient evoked otoacoustic emissions taking the least time. Ambient noise levels differed between wards and clinics with the sound level readings ranging between 50 dBA and 70 dBA. The most suitable screening time was found to be the afternoons, after feeding times.

Conclusion

Findings highlight important considerations when embarking on larger scale NHS studies or when planning a hospital NHS programme. Current findings suggest that NHS can be efficiently and effectively conducted in public sector hospitals in South Africa, provided that test time is considered in addition to sensitivity and specificity when deciding on a screening protocol; bar recognised personnel challenges.

Avaliação do programa de triagem auditiva neonatal da Clínica Escola do Univag

RESUMO Objetivo: verificar se a porcentagem de recém-nascidos que falharam na triagem auditiva do serviço da Clínica Escola do Centro Universitário de Várzea Grande está dentro do determinado pelos indicadores de qualidade dos serviços de Triagem Auditiva Neonatal. Método: estudo retrospectivo, no qual foram analisados os resultados dos exames de Emissões Otoacústicas Transientes realizados no período de Outubro de 2013 a Agosto de 2014, em um serviço gratuito de triagem auditiva neonatal opcional do setor privado de uma universidade da cidade de Várzea Grande-Mato Grosso, Brasil. Compuseram a amostra 251 participantes, subdivididos em dois grupos: grupo de baixo risco composto por 210 participantes, sendo 100 do gênero feminino e 110 do masculino e; grupo de alto risco composto por 41 participantes, sendo 17 do gênero feminino e 24 do masculino. Resultados: foram analisados os resultados da triagem auditiva obtidas com o teste das Emissões Otoacústicas Transientes sendo que no grupo de baixo risco 39,52% passaram, 4,76% falharam e 55,71% não compareceram ao serviço para finalização da triagem. Já no grupo de alto risco, 48,78% passaram, 14,63% falharam e 36,59% não compareceram ao serviço para finalização da triagem, conforme demonstrado nas Tabelas 1 e 2. Conclusão: a porcentagem de indivíduos que falharam na triagem auditiva neonatal pelo serviço avaliado está acima do preconizado pela literatura.