[Study on the clinical characteristics of auditory neuropathy patients with normal pure tone average or mild hearing loss].

Objective: The purpose of this study was to analyze the clinical characteristics of auditory neuropathy (AN) patients with normal hearing or mild hearing loss. Methods: Data from Multicenter Study on Clinical Diagnosis and Intervention of Acoustic Neuropathy (registration number: ChiCTR2100050125). According to the Chinese clinical practice guideline of auditory neuropathy (version 2022), these patients divided into two groups: the normal hearing group (PTA Normal, PTAN group, the average hearing threshold<20 dB HL) and the mild hearing loss group (PTA Mild hearing loss, PTAM group, the average hearing threshold between 20-35 dBHL). The audiology characteristics, clinical features, and follow-up were analyzed. Data analysis was conducted using GraphPad Prism 8 and SPSS 20.0 software. Results: A total of 75 AN with normal hearing or mild hearing loss were included in this study. The PTAN group consisted of 19 patients (38 ears), including 12 males and 7 females. The average onset age was (16.9±4.5) years old, while the test age was (22.1±5.8) years old for PTAN group. The PTAM group consisted of 56 patients (112 ears), including 29 males and 27 females. The average onset age was (16.2±7.9) years old, while the test age was (23.9±9.0) yeas old for PTAM group. The average hearing threshold of low frequency (0.125-0.5 kHz) was significantly decreased. ABR disappeared in 86.00% (126/150) of the patients. The speech recognition rate was 71.80±22.44% in the PTAN group and 58.08±29.28% in the PTAM group.-SP/AP was 0.98±0.47 in the PTAN and 1.07±0.63 in PTAM group; 40 (53.33%) patients had tinnitus. 29 patients (58 ears) were followed up, including 10 patients (20 ears) in the PTAN group and 19 patients (38 ears) in the PTAM group. There was no significant change in hearing threshold in short-term follow-up (<3 years). With the extension of the disease duration (>3 years), the PTAN group tended to decrease at low frequency, and the PTAM group decreased at high frequency first. The hearing threshold at 0.25 kHz in the PTAN group and 4 kHz in the PTAM group decreased significantly. Conclusions: AN patients with normal hearing or mild hearing loss exhibit abnormal results in audiological examination results, including ABR, electrocochleography and speech discrimination score. A combination of audiological tests should be used to make the diagnosis of AN. With the progression of the disease, AN with normal hearing or mild hearing loss tends to decrease.

[Recognition of unilateral auditory neuropathy in children].

Objective: This study aimed to compare the audiological characteristics between children with unilateral auditory neuropathy (UAN) and single-sided deafness (SSD) to establish a valid basis for the differential diagnosis of children with UAN. Methods: A retrospective analysis was conducted on audiological and imaging evaluations of children with UAN and SSD who were treated at Beijing Children's Hospital of Capital Medical University between May 2015 and June 2023. There were 17 children with UAN, comprising 10 males and 7 females, with an average age of 4.7 years. Additionally, there were 43 children with SSD, consisting of 27 males and 16 females, with an average age of 6.5 years. Audiological assessments included Auditory brainstem response (ABR), Steady-state auditory evoked potential (ASSR), Behavioural audiometry, Cochlear microphonic potential (CM), Distortino-product otoacoustic emission (DPOAE), and acoustic immittance test. The results of the audiological assessment and imaging phenotypic between the two groups of children were compared and analyzed by applying SPSS 27.0 statistical software. Results: (1) The UAN group (77.8%) had a significantly higher rate of ABR wave IIIL than the SSD group (20.9%) (P<0.01). The PA thresholds at 500 Hz and 1 000 Hz of children with SSD were higher than those of children with UAN, while the ASSR thresholds at 500 Hz, 1000 Hz, 2 000 Hz, and 4 000 Hz of children with SSD were significantly higher than those of children with UAN (P<0.05). (2) The degree of hearing loss in both UAN and SSD children was predominantly complete hearing loss. The percentage of complete hearing loss was significantly higher (χ²=4.353, P=0.037) in the SSD group (93.0%, 40/43) than in the UAN group (63.6%, 7/11). However, the percentage of profound hearing loss was significantly higher in the UAN group (27.3%, 3/11) than in the SSD group (2.3%, 1/43) (Fisher's exact test, P=0.023). In terms of hearing curve configuration, the percentage of flat type was significantly higher in the SSD group (76.7%, 33/43) than in the UAN group (36.4%, 4/11). The proportion of the UAN group (27.3%, 3/11) was significantly higher than that in the SSD group (2.3%, 1/43) in ascending type (P<0.05). There were no statistically significant differences in the hearing curves of the declining type and other types between the two groups (P>0.05). (3) The proportion of imaging assessment without abnormality was significantly more common in the UAN group (81.8%) than in the SSD group (37.1%) (χ²=6.695, P=0.015). Conclusions: Compared to children with SSD, the occurrence of wave IIIL on the ABR test was significantly more common in children with UAN. The percentage of ascending hearing curves was significantly higher in children with UAN than in children with SSD. ASSR thresholds were significantly lower in children with UAN. The normal imaging phenotype was significantly more common in children with UAN than in children with SSD.

[Research on the variation in distortion product otoacoustic emissions in patients with auditory neuropathy during the natural course of the disease].

Objective: The purpose of this study was to investigate the characteristics of distortion product otoacoustic emissions (DPOAE) in patients with auditory neuropathy (AN). The factors affecting DPOAE elicitation rate of each frequency, elicitation rate of each ear and change rate of first and last diagnosis in the natural course were analyzed. Methods: The sample was obtained from the Multicenter Study on Clinical Diagnosis and Intervention of AN (registration number: ChiCTR2100050125), and the diagnostic criteria for AN were based on the Chinese Clinical Practice Guidelines of Auditory Neuropathy (version 2022). Patients with bilateral AN who underwent 2 or more DPOAE tests were screened and divided into infant groups (≤3 years old) and non-infant groups (>3 years old) according to the age of detection, and the trend of DPOAE elicitation rate of each frequency, elicitation rate of each ear and change rate in the natural course of disease were analyzed, in order to explore the relevant influencing factors. Results: A total of 165 patients (330 ears) with AN were included in the study. The overall DPOAE elicitation rate per ear was 77.0%±29.4% at the initial diagnosis and 65.1%±35.2% at the final diagnosis, with a reduction observed in the elicitation rate of 171 ears (51.82%). In the infant group, there were 49 cases (98 ears), including 28 males and 21 females, whose found age ranged from 0 to 3 years old, with a median age of 0.7 years. DPOAE elicitation rate per ear was 57.9%±35.5% in the initial diagnosis, and 32.4%±32.1% in the final diagnosis, with a reduction observed in the elicitation rate of 69 ears (70.41%). In the non-infant group, there were 116 cases (232 ears), including 59 males and 57 females, ranging in found age from 3.9 to 40 years old, with a median age of 14 years old. DPOAE elicitation rate per ear was 84.6%±23.4% in the initial diagnosis, and 78.3%±27.1% in the final diagnosis, with a reduction observed in the elicitation rate of 102 ears (43.97%). Age was found to be correlated with DPOAE changes by multicategorical unordered logistic regression analysis (B=-0.224, OR=0.799, P<0.001). Conclusions: The elicitation rate of DPOAE in AN patients decreases or even disappears with increasing disease duration; The rate of DPOAE extraction is found to be lower in infant patients with auditory neuropathy (AN) compared to non-infant AN patients. Additionally, it is observed that the decrease in DPOAE extraction rate is more pronounced in infant AN patients as the disease progressed, as compared to non-infant AN patients. DPOAE and cochlear microphonic potentials should be fully combined for accurate diagnosis, and regular follow-up should be conducted to understand the natural course of the disease and give personalized guidance and assistance.

Auditory Neuropathy Spectrum Disorder Progressing with Motor and Sensory Neuropathy Caused by an ATP1A1 Variant.

We encountered a 27-year-old Japanese woman with sensorineural deafness progressing to motor and sensory neuropathy. At 16 years old, she had developed weakness in her lower extremities and hearing impairment, which gradually deteriorated. At 22 years old, combined audiological, electrophysiological, and radiological examination results were consistent with auditory neuropathy spectrum disorder (ANSD). Genetic analyses identified a previously reported missense variant in the ATP1A1 gene (NM_000701.8:c.1799C>G, p.Pro600Arg). Although sensorineural deafness has been reported as a clinical manifestation of ATP1A1-related disorders, our case suggested that ANSD may underlie the pathogenesis of deafness in ATP1A1-related disorders. This case report broadens the genotype-phenotype spectrum of ATP1A1-related disorders.

[The follow-up study on patients of children with auditory neuropathy].

Objective:To analyse the audiological characteristics of patients of children with auditory neuropathy（AN） for gaining a better understanding of the audiological characteristics prognosis of patients with AN. Methods:58 patients（108 ears） of children with AN were enrolled, all of whom had received further consultation within 10 years after the first consultation. Behavioral audiometry test, tympanogram test, distortion product otoacoustic emission（DPOAE）, auditory brainstem response（ABR）, cochlear microphonics（CM）, auditory steady-state response（ASSR） were performed on these patients. Results:①There were no significant changes in behavioral audiometry threshold between first and further consultation（P>0.05）；②Tympanograms were mostly of type A or As； ③The patients had worse DPOAE results in the further consultation, while the elicitation rate of other frequencies were higher except for the lower elicitation rate of 750 Hz and 1000 Hz；④There were 7 ears that had present ABR and CM in the first consultation, while three ears had present ABR and CM in the further consultation；⑤Except for 500 Hz, other frequency thresholds of ASSR in the further consultation were statistically significant compared with those in the first consultation（P<0.01）；⑥The threshold of behavioral audiometry at 4000 Hz was higher than that of ASSR, and there was no obvious correlation between the other frequencies（P>0.05）. Conclusion:There is a tendency of hearing deterioration in patients of children with AN. Patients with no DPOAE elicitation and no ABR elicitation or serious abnormalities need CM test to avoid misdiagnosis. The hearing status and speech communication ability of patients should be continuously monitored. Parents should pay attention to the changes in the behavioral ability of the children in daily life and make regular subsequent visits.

Results of cochlear implant surgery in patients with auditory neuropathy.

OBJECTIVES: The primary aim of this study was to analyze the benefit of cochlear implants for patients with auditory neuropathy. The secondary aim was to identify risk factors for auditory neuropathy. MATERIALS AND METHODS: Patients with cochlear implants (CIs) who were educated in hearing rehabilitation schools were included in the study. A total of 175 children were operated on for cochlear implantation between August 2019 and August 2021 in the department of otorhinolaryngology at different centers in Turkey, and while 16 (9.1%) of those patients had auditory neuropathy spectrum disorder (ANSD), 159 (90.9%) had sensorineural hearing loss (SNHL). Differences in auditory perception between the two groups were examined. Auditory perception tests were applied for these patients 6 months after CI surgery. The auditory perception performances of the patients were evaluated with the Evaluation of Auditory Responses to Speech (EARS) battery, including the Littlears, Lip, Bis4, Bis12, Cap, Sir, Mtp-3, Mtp-6, Mtp-12, Matrix A1, and Gasp tests. RESULTS: All patients had profound bilateral SNHL. Four auditory perception tests (Littlears, Bis-12, Sir, Matrix A1) showed similar results between patients with ANSD and SNHL, but seven auditory perception tests (Lip, Bis-4, Cap, Mtp-3, Mtp-6, Mtp-12, Gasp) showed significantly higher results among patients with SNHL. Hyperbilirubinemia, prematurity, consanguineous marriage, and family history of hearing loss were found to be common among patients with ANSD. CONCLUSIONS: ANSD patients who do not benefit from hearing aids benefit from CI surgery.

Diagnosis of Auditory Neuropathy Spectrum Disorder in the Neonatal Intensive Care Unit Population.

OBJECTIVE: To determine the incidence of auditory neuropathy spectrum disorder (ANSD) and its risk factors among the neonatal intensive care unit (NICU) population from 2009 to 2018 in the Pediatric Health Information System database. STUDY DESIGN: Retrospective national database review. SETTING: Population-based study. METHODS: The Pediatric Health Information System database was queried to identify patients ≤18 years old with NICU admission and ANSD diagnosis. Patient demographics, jaundice diagnosis, use of mechanical ventilation, extracorporeal membrane oxygenation, furosemide, and/or aminoglycosides were extracted. Multivariable linear regression was used to assess trends in incidence. Chi-square analysis was used to assess differences between patients with and without ANSD. Logistic regression was used to assess factors associated with ANSD. RESULTS: From 2009 to 2018, there was an increase in (1) NICU admissions from 14,079 to 24,851 (P < .001), (2) total ANSD diagnoses from 92 to 1847 (P = .001), and (3) annual total number of patients with ANSD and NICU admission increased from 4 to 16 (P = .005). There was strong correlation between the increases in total number of NICU admissions and total ANSD diagnoses over time (R = 0.76). The average ANSD incidence was 0.052% with no statistically significant change over 10 years. When compared with all NICU admissions, children with ANSD had a higher association with use of furosemide (P < .001) and ventilator (P < .001). CONCLUSION: Despite a statistically significant increase in NICU admissions and total ANSD diagnosis, the incidence of ANSD in the NICU population has not increased from 2009 to 2018. Furosemide and mechanical ventilator use were associated with increased likelihood of ANSD.

Neural representation of consonant-vowel transition in individuals with cochlear hearing loss and auditory neuropathy spectrum disorder.

PURPOSE: Acoustic change complex (ACC) is an evoked potential recorded in response to subtle change(s) in the continuing stimuli. It is assumed that poor speech perception can be due to poor encoding of consonant-vowel (CV) transition in cochlear hearing loss (CHL) and auditory neuropathy spectrum disorder (ANSD). The present study aims to investigate the use of ACC as an objective tool to study neural representation of CV transition in individuals with ANSD, CHL, and normal hearing (NH). METHODS: The study consisted of three groups of population (NH, ANSD, and CHL) in the age range of 18-40 years. ACC was recorded for naturally produced CV stimulus /sa/ of 380 ms in duration, which consists consonant (150 ms) and vowel (230 ms) using Biologic Navigator pro 7.2.1. RESULTS: The result showed significantly prolonged latencies of ACC in individuals with ANSD compared to NH. The current study also showed significantly prolonged latency and significantly lower peak-to-peak amplitude in individuals with ANSD compared to CHL. The interesting finding of the present study was significantly better peak-to-peak amplitude for CHL compared to NH. Whereas, there was no significant difference between NH and CHL for latencies measures. CONCLUSION: Poor neural synchronization in individuals with ANSD could be the reason of poor neural representation of CV transition in present study. The outcome of the present study showed poor neural representation of CV transition in individuals with ANSD compared to CHL and NH. Current study also showed better encoding of CV transition in individuals with CHL compared to ANSD.

ATP1A3 mutations can cause progressive auditory neuropathy: a new gene of auditory synaptopathy.

The etiologies and prevalence of sporadic, postlingual-onset, progressive auditory neuropathy spectrum disorder (ANSD) have rarely been documented. Thus, we aimed to evaluate the prevalence and molecular etiologies of these cases. Three out of 106 sporadic progressive hearing losses turned out to manifest ANSD. Through whole exome sequencing and subsequent bioinformatics analysis, two out of the three were found to share a de novo variant, p.E818K of ATP1A3, which had been reported to cause exclusively CAPOS (cerebellar ataxia, areflexia, pes cavus, optic atrophy, and sensorineural hearing loss) syndrome. However, hearing loss induced by CAPOS has never been characterized to date. Interestingly, the first proband did not manifest any features of CAPOS, except subclinical areflexia; however, the phenotypes of second proband was compatible with that of CAPOS, making this the first reported CAPOS allele in Koreans. This ANSD phenotype was compatible with known expression of ATP1A3 mainly in the synapse between afferent nerve and inner hair cells. Based on this, cochlear implantation (CI) was performed in the first proband, leading to remarkable benefits. Collectively, the de novo ATP1A3 variant can cause postlingual-onset auditory synaptopathy, making this gene a significant contributor to sporadic progressive ANSD and a biomarker ensuring favorable short-term CI outcomes.

The management of pediatric hearing loss caused by auditory neuropathy spectrum disorder.

PURPOSE OF REVIEW: Auditory neuropathy spectrum disorder (ANSD) is a condition in which auditory testing reveals normal otoacoustic emissions, but auditory brainstem testing is abnormal or absent and speech discrimination is poor. This constellation of findings ostensibly suggests that the cochlea is healthy and an abnormality of conduction or processing of sound occurs along the nerve fibers. As more is learned about this condition, it is becoming clear that ANSD describes heterogeneous, distinct clinical entities that must be taken into account when devising treatment modalities. RECENT FINDINGS: Modern auditory testing, genetic testing, and neuroimaging can allow for an accurate understanding of the location of the lesion causing ANSD in the auditory pathway. Contributing causes can include genetic mutations, absent or deficient cochlear nerve, hypoxia and jaundice among others. Hearing aids can be successful in the management of ANSD. Several studies suggest that cochlear implantation can lead to successful hearing outcomes in a subset of this patient population. SUMMARY: Auditory neuropathy spectrum disorder represents a relatively rare but important diagnosis for clinicians. Treatment for this condition includes hearing aids and FM systems in more mild cases, and cochlear implants in severe cases. Cochlear implantation for many patients can lead to a good hearing outcomes but the outcome can vary greatly depending on the underlying etiology of ANSD.

International Pediatric Otolaryngology Group (IPOG) consensus recommendations: Hearing loss in the pediatric patient.

OBJECTIVE: To provide recommendations for the workup of hearing loss in the pediatric patient. METHODS: Expert opinion by the members of the International Pediatric Otolaryngology Group. RESULTS: Consensus recommendations include initial screening and diagnosis as well as the workup of sensorineural, conductive and mixed hearing loss in children. The consensus statement discusses the role of genetic testing and imaging and provides algorithms to guide the workup of children with hearing loss. CONCLUSION: The workup of children with hearing loss can be guided by the recommendations provided herein.

Management of children with auditory neuropathy spectrum disorder (ANSD) / Tratamento de crianças com espectro da neuropatia auditiva (ENA)

ABSTRACT INTRODUCTION: ANSD is a challenging problem. OBJECTIVE: To present our experience on management of the children with ANSD with respect to clinical data. METHODS: This retrospective study included all children younger than 16 years of age who applied to the department between 2005 and 2013 (with the exception of newborn hearing screening NHS referrals). The data were derived from pure tone, OAEs and ABR tests, and further medical risk factors of the subjects were evaluated. RESULTS: ANSD was recognized in 74 ears of 40 children (B/U: 34/6) among 1952 children with SNHL (2.04%) detected among 9520 applicants to the department (0.42%). The clinical tests revealed that hearing loss greater than 15 dB was present in both ears of 38 cases. The degree of hearing loss was profound in 48% children, severe in 12% children, moderate in 28% children, mild in 10% children and normal in 5% children. ABRs were absent/abnormal in 37/3 ears and CMs were detected in all. Acoustic reflexes were absent in all ears. Rehabilitation was managed by CI and hearing aids in 15 and 23 cases, respectively. FM system was given to two cases displaying normal hearing but poor speech discrimination in noisy environments. CONCLUSION: ANSD is a relatively challenging problem for the audiology departments because of its various clinical features and difficulties in management. Our patients with ANSD most commonly displayed profound hearing loss. The number of overlooked cases may be minimized by performing ABR and OAE in every case referred with the suspicion of hearing loss.

Resumo Introdução: Espectro da neuropatia auditiva ainda é uma condição clínica desafiadora. Objetivo: Apresentar nossa experiência no tratamento de crianças com espectro da neuropatia auditiva em relação aos dados clínicos. Método: Este estudo retrospectivo incluiu crianças menores de 16 anos de idade que deram entrada no departamento entre 2005 e 2013 (com exceção de encaminhamentos para triagem auditiva neonatal). Foram avaliados os dados obtidos a partir dos exames de audiometria tonal, emissões otoacústicas (EOA), potencial evocado auditivo de tronco encefálico (ABR) e outros fatores de risco. Resultados: Das 1.952 crianças com perda auditiva neurossensorial (2,04%) detectadas dentre os 9.520 candidatos que deram entrada no departamento (0,42%), espectro da neuropatia auditiva foi reconhecida em 74 orelhas de 40 crianças (B/U: 34/6). Os testes clínicos revelaram que uma perda auditiva superior a 15 dB estava presente em ambas as orelhas em 38 casos. O grau de perda auditiva das crianças era profundo em 48%, grave em 12%, moderado em 28%, leve em 10%, e normal em 5%. ABR estava ausente/anormal em 37/3 orelhas e microfonia coclear foi detectado em todas as crianças. Reflexos acústicos estavam ausentes em todas as orelhas. A reabilitação foi tratada com implante coclear e aparelhos auditivos em 15 e 23 casos, respectivamente. Um sistema FM foi utilizado em dois casos que apresentavam audição normal, mas discriminação deficiente da fala em ambientes ruidosos. Conclusão: Espectro da neuropatia auditiva é um problema desafiador para os departamentos de audiologia, devido às suas várias características clínicas e dificuldades no tratamento. Em nossos pacientes a perda auditiva profunda foi a mais frequente. O número de casos negligenciados pode ser diminuído com a realização dos exames ABR e EOA em todos os casos encaminhados com suspeita de perda auditiva.

Performance of Cochlear Implants in Pediatric Patients with Auditory Neuropathy Spectrum Disorder.

OBJECTIVE: To describe the performance and results of CIs (cochlear implant) in patients with AN (auditory neuropathy) and to present a medical literature review. MATERIALS AND METHODS: Retrospective chart review of patients with AN who were treated with CI. The mesh terms used for the review in the Pubmed and Scopus databases were as follows: "hearing loss, cochlear implants, rehabilitation of persons with hearing impairment, auditory neuropathy". STATISTICAL ANALYSES: The Mann-Whitney test was performed. RESULTS: The sample consisted of 10 patients. The mean age at surgery was 4.3 years, range 2-16 years. The average length of CI use was 5.2 years. The comparison of hearing levels before and after CI use showed a significant improvement in all patients, with p<0.05. All of them also reported an increase in overall satisfaction 1 year after the procedure. A CI is the standard treatment for the hearing rehabilitation of patients with severe profound hearing loss who do not benefit from conventional hearing aids. There are diseases such as AN that also invoke a discussion in the literature regarding CI benefits. CONCLUSION: Individuals with an demonstrated a significant gain in hearing levels and language use with CI.

Acquired auditory neuropathy spectrum disorder after an attack of chikungunya: case study.

Auditory neuropathy spectrum disorder (ANSD) is a retrocochlear disorder in which the cochlear functioning is normal but the transmission in the auditory neural pathway is affected. The present study reports of a 14-year-old teenager with acquired ANSD after an attack of chikungunya. He reported symptoms of difficulty in understanding speech, tinnitus and vertigo when exposed to loud sounds. The audiological characteristics suggested auditory neuropathy spectrum disorder with raising audiogram configuration. The results of tinnitus evaluation showed low-pitched tinnitus and it was persistent causing significant handicap to him based on self report tinnitus handicap questionnaire results. The results of depression, anxiety and stress scale also suggested symptoms of mild depression and anxiety. Chikungunya virus is suspected to be neurotropic in nature which can damage auditory nerve cells and may have caused ANSD. The result also shows presence of tullio's phenomenon and absence of cervical vestibular evoked myogenic potentials suggesting damage to the vestibular neuronal system. The possible pathophysiology of chikungunya virus causing ANSD and vestibular symptoms needs to be explored further in future studies.

[An analysis of various diseases and hearing screening in NICU infants].

Objective:It is the first time to study the hearing screening results in NICU infants in Heilongjiang province,to analyze the various diseases and hearing loss distribution in NICU infants.Method:Three hundred and thirty four newborns(668 ears) in NICU received hearing screening with TEOAE and AABR test.We compared the results of different risk factors.Result:The failed ratio of different diseases in NICU are as follow: premature infants 61%,hypoxic-ischemic encephalopathy(HIE) 35%,neonatal infectious pneumonia 30%,neonatal sepsis 30%,neonatal aspiration pneumonitis 36%,neonatal jaundice 29%.Conclusion:The positive ratio of preterm infants was 61%,which is higher than the other diseases in NICU infants of Heilongjiang province.Both TEOAE and AABR failure have a high incidence of abnormal hearing status.Neonatal jaundice,neonatal infectious pneumonia and premature infants diseases are the high risk factors of auditory neuropathy spectrum disorder(ANSD) in NICU infants of Heilongjiang.

Audiological changes over time in adolescents and young adults with auditory neuropathy spectrum disorder.

Auditory neuropathy spectrum disorder (ANSD) describes a condition in which a patient's otoacoustic emissions (OAE) are (or were at one time) present and auditory brainstem responses (ABR) are abnormal or absent. ANSD is also diagnosed based on the presence of cochlear microphonics and abnormal or absent ABRs with or without abnormalities of OAE. We noted the changes in audiological characteristics over time with respect to pure tone thresholds, OAEs and Speech Identification Scores (SIS) in seven individuals with ANSD. The results indicated that all the individuals with ANSD had decreased SIS over time, whereas there was subsequent reduction in pure tone thresholds only in nine out of fourteen ears. There was absence of OAEs for two individuals in both ears during the follow-up evaluations. There was no regular pattern of changes in pure tone thresholds or SIS across all individuals. This indicates that there may be gradual worsening of hearing abilities in individuals with ANSD. Thus, regular follow-up and monitoring of audiological changes are necessary for individuals with ANSD. Also, longitudinal studies need to be done to further add evidence to the audiological changes over time in individuals with ANSD.

Unilateral auditory neuropathy spectrum disorder: retrocochlear lesion in disguise?

OBJECTIVE: To investigate whether the aetiology for hearing impairment in neonates with unilateral auditory neuropathy spectrum disorder could be explained by structural abnormalities such as cochlear nerve aplasia, a cerebellopontine angle tumour or another identifiable lesion. METHODS: In this prospective case series, 17 neonates were diagnosed with unilateral auditory neuropathy spectrum disorder on electrophysiological testing. Diagnostic audiology testing, including auditory brainstem response testing, was supplemented with computed tomography and/or magnetic resonance imaging. RESULTS: Ten of the neonates (59 per cent) showed evidence for cochlear nerve aplasia. Of the remaining seven, four were shown to have another abnormality of the temporal bone on imaging. Only three neonates (18 per cent) were not diagnosed with cochlear nerve aplasia or another lesion. Three computed tomography scans were reported as normal, but subsequent magnetic resonance imaging revealed cochlear nerve aplasia. CONCLUSION: Auditory neuropathy spectrum disorder as a unilateral condition mandates further investigation for a definitive diagnosis. This series demonstrates that most neonates with unilateral auditory neuropathy spectrum disorder had pathology as visualised on computed tomography and/or magnetic resonance imaging scans. Magnetic resonance imaging is an appropriate first-line imaging modality.

[Analysis of characteristics of tinnitus in patients with auditory neuropathy spectrum disorder].

OBJECTIVE: To investigate the characteristics of tinnitus in patients with auditory neuropathy spec- trum disorder (ANSD). METHOD: This study recruited 14 ANSD patients with tinnitus. All the ANSD patients un- derwent detailed history taking, audiological examinations and assessments of tinnitus. This study analyzed the correlation of tinnitus status and hearing loss, and discussed the effects of sex, age, and the course of disease on tinnitus in ANSD patients. RESULT: (1) In the ANSD patients, tinnitus often occurred in 3 years after the onset of hearing loss; (2) Tinnitus was highly prevalent in ANSD patients, and the severity of tinnitus was mostly from mild to moderate; (3) There was no obvious correlation between the subjective grading of tinnitus and hearing loss de- gree, and the impact of curve patterns of hearing loss on the level of tinnitus need much more evidence-based proof; (4) Along with the course extension, the impact of tinnitus on the quality of life was much more obvious; (5) Some risk factors such as noise exposure could be the reasons of aggravating the degree of tinnitus. CONCLUSION: Tinnitus in ANSD patients has its unique clinical features. The study of Tinnitus in ANSD patients can provide clinical basis for further research in ANSD.