Auditory neuropathy in a patient exposed to xylene: case report

AbstractObjective:To report the case of an adult patient who developed auditory complaints following xylene exposure, and to review the literature on the effects of solvent exposure on hearing.Case report:The patient presented with a gradual deterioration in his ability to hear in difficult acoustic environments and also to hear complex sounds such as music, over a 40-year period. His symptoms began following exposure to the solvent xylene, and in the absence of any other risk factor. Our audiological investigations revealed normal otoacoustic emissions with absent auditory brainstem responses and absent acoustic reflexes in both ears, consistent with a diagnosis of bilateral auditory neuropathy. Central test results were also abnormal, indicating possible involvement of the central auditory pathway.Conclusions:To our knowledge, this is the first report of retrocochlear hearing loss following xylene exposure. The test results may provide some insight into the effect of xylene as an isolated agent on the human auditory pathway.

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Newborn Hearing Screening with Combined Otoacoustic Emissions and Auditory Brainstem Responses

Journal of the American Academy of Audiology ◽

10.3766/jaaa.15.6.3 ◽

2004 ◽

Vol 15 (06) ◽

pp. 414-425 ◽

Cited By ~ 39

Author(s):

James W. Hall ◽

Steven D. Smith ◽

Gerald R. Popelka

Keyword(s):

Auditory Brainstem Response ◽

Otoacoustic Emissions ◽

Auditory Brainstem ◽

Hearing Screening ◽

Auditory Neuropathy ◽

Diagnostic Evaluation ◽

Auditory Brainstem Responses ◽

Conductive Loss ◽

Brainstem Response ◽

Screening Measures

Accurate assessment of neonatal hearing screening performance is impossible without knowledge of the true status of hearing, a prohibitive requirement that necessitates a complete diagnostic evaluation on all babies screened. The purpose of this study was to circumvent this limitation by integrating two types of screening measures obtained near simultaneously on every baby. Peripheral auditory function was defined by otoacoustic emission results. A complete diagnostic evaluation was performed on every baby who received a "Refer" outcome for auditory brainstem response screening. The integrated results for auditory brainstem response screening in an unselected group of 300 newborns estimated sensitivity at 100%, specificity at 99.7%, overall referral rate at 2.0%, and a positive predictive value of 83.3%. Conductive loss associated with amniotic fluid in the middle ear can persist several weeks after birth; conductive loss can produce a "Refer" outcome for auditory brainstem response screening; and auditory neuropathy can be detected with screening measures. Prevalence results were consistent with the published literature. The implications of this study are that otoacoustic emissions and auditory brainstem measures provide much more information than either alone and that both are needed for a comprehensive hearing screening program.

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Neuropatia Auditiva: Avaliação Clínica e Abordagem Diagnóstica

Acta Médica Portuguesa ◽

10.20344/amp.6942 ◽

2016 ◽

Vol 29 (6) ◽

pp. 353 ◽

Cited By ~ 2

Author(s):

Guilherme Machado Carvalho ◽

Beatriz Prista Leão ◽

Priscila Zonzini Ramos ◽

Alexandre Caixeta Guimarães ◽

Arthur Menino Castilho ◽

...

Keyword(s):

Hearing Loss ◽

Case Series ◽

Epidemiological Data ◽

Auditory Pathway ◽

Auditory Brainstem ◽

Auditory Neuropathy ◽

Auditory Brainstem Responses ◽

Profound Deafness ◽

Neuronal Transmission ◽

Patients Experience

Introduction: Auditory neuropathy is a condition in which there is a change in the neuronal transmission of the auditory stimuli. Our objective was to describe the patients’ series within the clinical spectrum of auditory neuropathy. Material and Methods: We designed a transversal, retrospective study, with a description of a consecutive case series. Auditory neuropathy was defined by the presence of acoustic otoemissions plus absent/abnormal auditory brainstem responses with cochlear microphonism. Results: 34 patients with bilateral hearing loss, 23 males and 11 females, were included in the study. Eighty percent of the cases had congenital onset of hearing loss. Acoustic otoemissions were absent in 67% of them. Cochlear microfonism was present in 79% of all cases. Prenatal, perinatal or ambiental factors were present in 35.2% of the cases. Discussion: Medical literature shows great variability in findings related to auditory neuropathy, both in its etiology and epidemiological data. Conclusion: Auditory neuropathy presents a broad spectrum of changes that may result from mild to severe changes in the functioning of the auditory pathway, and in our sample we observed that 80% of Auditory neuropathy have congenital onset of hearing loss and/or with cochlear microphonism identified. 91% of patients experience significant hearing impairment and 53% suffer from severe or profound deafness.

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Auditory neuropathy in a patient with mitochondrial myopathy and multiple mtDNA deletions

The Journal of Laryngology & Otology ◽

10.1017/s0022215106001472 ◽

2006 ◽

Vol 120 (10) ◽

pp. 888-891 ◽

Cited By ~ 9

Author(s):

F Forli ◽

M Mancuso ◽

A Santoro ◽

M T Dotti ◽

G Siciliano ◽

...

Keyword(s):

Hair Cells ◽

Otoacoustic Emissions ◽

Mitochondrial Myopathy ◽

Spiral Ganglion ◽

Mitochondrial Diseases ◽

Auditory Brainstem ◽

Auditory Neuropathy ◽

Auditory Brainstem Responses ◽

Common Symptom ◽

First Case

Auditory neuropathy (AN) is a hearing disorder characterized by the absence or severe distortion of the auditory brainstem responses, in the presence of preserved otoacoustic emissions. This peculiar combination suggests the presence of a defect impinging upon the functional complex formed by inner hair cells, the primary afferents (spiral ganglion neurones) and the first order synapses between hair cells and the cochlear nerve. Typically, AN patients show a severe speech perception impairment, which appears reduced out of proportion to pure tone threshold, but the clinical presentation of AN is quite complex.Hearing loss is a common symptom associated with mitochondrial diseases; however, AN has only rarely been reported in these disorders.Here we report a rare association, the first case observed in Italy, in a patient with autosomal recessive mitochondrial myopathy and mitochondrial DNA multiple deletions, and a hearing deficit with the audiological and electrophysiological features of AN.

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Acquired auditory neuropathy spectrum disorder after malaria treated with quinine

Tropical Doctor ◽

10.1177/0049475520917236 ◽

2020 ◽

Vol 50 (3) ◽

pp. 246-248

Author(s):

Helen Brough

Keyword(s):

Auditory Nerve ◽

Otoacoustic Emissions ◽

Outer Hair Cell ◽

Cell Function ◽

Auditory Brainstem ◽

Auditory Neuropathy ◽

Spectrum Disorder ◽

Auditory Neuropathy Spectrum Disorder ◽

Acoustic Reflexes ◽

Brainstem Response

Auditory neuropathy spectrum disorder (ANSD) can cause significant hearing impairment; it occurs when there is intact outer hair cell function in the inner ear, with a dyssynchronous neural response, thought to be due to dysfunction of the inner hair cells (IHCs), the synapse of the IHCs and the auditory nerve, or of the auditory nerve itself. This case report describes the onset of ANSD in a Malawian child after severe malaria treated with quinine. Diagnosis of ANSD was made by confirming the presence of otoacoustic emissions, together with the absence of auditory brainstem response and absent acoustic reflexes.

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Unilateral Auditory Neuropathy Caused by Cochlear Nerve Deficiency

International Journal of Otolaryngology ◽

10.1155/2012/914986 ◽

2012 ◽

Vol 2012 ◽

pp. 1-5 ◽

Cited By ~ 6

Author(s):

Cheng Liu ◽

Xingkuan Bu ◽

Feiyun Wu ◽

Guangqian Xing

Keyword(s):

Otoacoustic Emissions ◽

Internal Auditory Canal ◽

Auditory Brainstem ◽

Auditory Neuropathy ◽

Cochlear Nerve ◽

Auditory Brainstem Responses ◽

Maximum Output ◽

Neural Responses ◽

Ear Effusion ◽

Cochlear Nerve Deficiency

Objective. To explore possible corelationship between the cochlear nerve deficiency (CND) and unilateral auditory neuropathy (AN).Methods. From a database of 85 patients with unilateral profound sensorineural hearing loss, eight who presented with evoked otoacoustic emissions (EOAEs) or cochlear microphonic (CM) in the affected ear were diagnosed with unilateral AN. Audiological and radiological records in eight patients with unilateral AN were retrospectively reviewed.Results. Eight cases were diagnosed as having unilateral AN caused by CND. Seven had type “A” tympanogram with normal EOAE in both ears. The other patient had unilateral type “B” tympanogram and absent OAE but CM recorded, consistent with middle ear effusion in the affected ear. For all the ears involved in the study, auditory brainstem responses (ABRs) were either absent or responded to the maximum output and the neural responses from the cochlea were not revealed when viewed by means of the oblique sagittal MRI on the internal auditory canal.Conclusion. Cochlear nerve deficiency can be seen by electrophysiological evidence and may be a significant cause of unilateral AN. Inclined sagittal MRI of the internal auditory canal is recommended for the diagnosis of this disorder.

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Audiological findings in glomus tumours

The Journal of Laryngology & Otology ◽

10.1017/s0022215100136953 ◽

1997 ◽

Vol 111 (3) ◽

pp. 218-222 ◽

Cited By ~ 2

Author(s):

William W. Qiu ◽

Shengguang S. Yin ◽

Fred J. Stucker ◽

Mardjohan Hardjasudarma

Keyword(s):

Magnetic Resonance Imaging ◽

Magnetic Resonance ◽

Auditory System ◽

Middle Ear ◽

Otoacoustic Emissions ◽

Cerebellopontine Angle ◽

Auditory Brainstem ◽

Auditory Brainstem Responses ◽

Resonance Imaging ◽

Magnetic Resonance Imaging Mri

AbstractGlomus tumours involving the middle ear and the cerebellopontine angle are reported with emphasis on audiological findings. Magnetic resonance imaging (MRI), angiographic and pathological results are presented. Audiological tests, including impedance audiometry, evoked otoacoustic emissions and auditory brainstem responses, are valuable in evaluation of the effect of glomus tumours on the auditory system as well as their pathological extent.

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Μελέτη των παραγόντων υψηλού κινδύνου για εμφάνιση βαρηκοΐας σε νεογνά της μονάδας εντατικής νοσηλείας

10.12681/eadd/39580 ◽

2016 ◽

Author(s):

Εμμανουήλ Νησωτάκης

Keyword(s):

Otoacoustic Emissions ◽

Auditory Brainstem ◽

Auditory Brainstem Responses ◽

Transiently Evoked Otoacoustic Emissions

Εισαγωγή Η συγγενής βαρηκοΐα είναι ίσως η πιο συχνή αισθητηριακή βλάβη της νεογνικής ηλικίας. Τα νοσηλευόμενα στη ΜΕΝΝ νεογνά θεωρείται ότι διατρέχουν μεγαλύτερο κίνδυνο για εμφάνιση είτε νευροαισθητήριας βαρηκοΐας είτε ακουστικής νευροπάθειας. Η σοβαρότητα της απώλειας ακοής κατά τη διάρκεια της πρώιμης κρίσιμης περιόδου ανάπτυξης του λόγου καθορίζει την απόκτηση επαρκούς γλωσσικής ικανότητας γι’ αυτό και είναι σημαντική η έγκαιρη διάγνωση και αντιμετώπιση κάθε υποκείμενης ακουστικής διαταραχής.Στη μελέτη αυτή εστιάζουμε στην παρουσία ακοολογικών παραγόντων κινδύνου και προσπαθούμε να διευκρινίσουμε την συσχέτισή τους με την εμφάνιση συγγενούς βαρηκοΐας, συμπεριλαμβανομένης και της ακουστικής νευροπάθειας, στον πληθυσμό των νεογνών της ΜΕΝΝ του νοσοκομείου μας.Ασθενείς και ΜέθοδοςΣτην παρούσα προοπτική μελέτη κοόρτης μελετήθηκαν 453 νεογνά τα οποία εισήχθησαν στη ΜΕΝΝ για περισσότερο από 24 ώρες μεταξύ 2012 και 2016 και εμφάνιζαν έναν ή περισσότερους παράγοντες κινδύνου. Όλα τα νεογνά υποβλήθηκαν σε ακοολογικό έλεγχο με χρήση αυτοματοποιημένων προκλητών δυναμικών του εγκεφαλικού στελέχους (automated Auditory Brainstem Responses – aABRs) σε συνδυασμό με παροδικά προκλητές ωτοακουστικές εκπομπές (Transiently Evoked OtoAcoustic Emissions – TEOAEs) τουλάχιστον 48 ώρες μετά τη γέννησή τους. Τα νεογνά που απέτυχαν στην αρχική εξέταση επανεξετάζονταν πριν τον πρώτο μήνα ζωής κι επί αποτυχίας παραπέμπονταν στο ιατρείο παιδικής βαρηκοΐας για πλήρη ακοολογικό έλεγχο. ΑποτελέσματαΑπό τον συνολικό αριθμό των 453 νεογνών 71 απέτυχαν στον αρχικό ακοολογικό έλεγχο. Μόνο 49 προσήλθαν για επανεξέταση και τελικά 8 νεογνά (1.8%) απέτυχαν τόσο στα a-ABRs όσο και στις TEOAEs και διαγνώσθηκαν με πιθανή νευροαισθητήρια βαρηκοΐα, ενώ σε επίσης 8 νεογνά (1.8%) οι TEOAEs εκλύθηκαν φυσιολογικά αλλά απέτυχαν στα a-ABRs οπότε διαγνώσθηκαν με πιθανή ακουστική νευροπάθεια. Από τους 13 ανεξάρτητους παράγοντες κινδύνου που ελέγχθηκαν η ωτοτοξικότητα των χορηγούμενων φαρμάκων, η μηχανική υποστήριξη της αναπνοής, το χαμηλό βάρος γέννησης και η υπερχολερυθριναιμία ήταν οι πιο συχνά εμφανιζόμενοι. Η πλειοψηφία των νεογνών (48%) εμφάνιζε ταυτόχρονα δύο παράγοντες κινδύνου. Το χαμηλό βάρος γέννησης βρέθηκε να συσχετίζεται με την εμφάνιση πιθανής νευροαισθητήριας βαρηκοΐας (p=0.002), ενώ οι κρανιοπροσωπικές ανωμαλίες και οι λοιμώξεις της ομάδας TORCH παρουσίασαν στατιστικά σημαντική συμμετοχή (p=0.03 και p=0.05 αντίστοιχα) στην ανάπτυξη πιθανής απώλειας ακοής συμπεριλαμβανομένης και της ακουστικής νευροπάθειας.ΣυμπεράσματαΤα προκλητά δυναμικά του εγκεφαλικού στελέχους (ABRs) και οι ωτοακουστικές εκπομπές (OAEs) αποτελούν τους θεμέλιους λίθους του καθολικού νεογνικού ελέγχου ακοής στη ΜΕΝΝ καθώς σημαντικός αριθμός παιδιών μπορεί να πάσχει από ακουστική νευροπάθεια. Η συνεχής επανεξέταση των παραγόντων κινδύνου και της συμβολής τους στην εμφάνιση βαρηκοΐας κρίνεται απαραίτητη καθώς αυτοί μεταβάλλονται. Απαιτείται ένα αποδοτικό σύστημα γραμματειακής υποστήριξης προκειμένου να ελαττωθεί το ποσοστό των νεογνών που δεν προσέρχονται για επανεξέταση.

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Gender Differences in Audiological Findings and Hearing Aid Benefit in 255 Individuals with Auditory Neuropathy Spectrum Disorder: A Retrospective Study

Journal of the American Academy of Audiology ◽

10.3766/jaaa.15145 ◽

2016 ◽

Vol 27 (10) ◽

pp. 839-845 ◽

Cited By ~ 5

Author(s):

Vijaya Kumar Narne ◽

Prashanth Prabhu ◽

Hunsur S. Chandan ◽

Mahadeva Deepthi

Keyword(s):

Gender Differences ◽

Retrospective Study ◽

Hearing Aids ◽

Otoacoustic Emissions ◽

Hearing Aid ◽

Auditory Neuropathy ◽

Spectrum Disorder ◽

Auditory Neuropathy Spectrum Disorder ◽

Acoustic Reflexes ◽

Hearing Aid Benefit

Background: There are many studies reported in the literature that have summarized audiological findings and possible rehabilitation in individuals with auditory neuropathy spectrum disorder (ANSD). However, there are very few studies that have attempted to delineate the gender differences in audiological characteristics and hearing aid benefit in individuals with ANSD. Purpose: The study aimed to explore the differences between males and females in terms of demographic details, audiogram, speech identification scores, otoacoustic emissions, acoustic reflexes, long latency responses, and hearing aid benefit. Research Design: A retrospective study. Study Sample: A total of 255 individuals diagnosed with ANSD were selected for the study. The study included 137 females and 88 males. Data Collection and Analysis: The demographic details, results of diagnostic audiological testing, and hearing aid benefit were analyzed retrospectively. The differences in findings across gender were compared. Results: The study shows that females have a relatively higher degree of hearing loss and that the majority of females show a rising type of audiometric configuration. The study shows that females have poorer speech perception abilities and experience limited benefits from hearing aids compared to males. Conclusions: The results of the study show that there are gender differences in audiological findings and hearing aid benefits in individuals with ANSD. However, well-controlled prospective studies are essential to confirm the results obtained and to identify the possible mechanisms underlying the gender differences.

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Cochlear Synaptopathy: A Primary Factor Affecting Speech Recognition Performance in Presbycusis

BioMed Research International ◽

10.1155/2021/6667531 ◽

2021 ◽

Vol 2021 ◽

pp. 1-7

Author(s):

Zhe Chen ◽

Yanmei Zhang ◽

Junbo Zhang ◽

Rui Zhou ◽

Zhen Zhong ◽

...

Keyword(s):

Speech Recognition ◽

Action Potential ◽

Animal Studies ◽

Signal To Noise Ratio ◽

Recognition Performance ◽

Auditory Pathway ◽

Auditory Brainstem ◽

Auditory Brainstem Responses ◽

Hearing Ability ◽

Summating Potential

The results of recent animal studies have suggested that cochlear synaptopathy may be an important factor involved in presbycusis. Therefore, here, we aimed to examine whether cochlear synaptopathy frequently exists in patients with presbycusis and to describe the effect of cochlear synaptopathy on speech recognition in noise. Based on the medical history and an audiological examination, 94 elderly patients with bilateral, symmetrical, sensorineural hearing loss were diagnosed as presbycusis. An electrocochleogram, auditory brainstem responses, auditory cortical evoked potentials, and speech audiometry were recorded to access the function of the auditory pathway. First, 65 ears with hearing levels of 41-50 dB HL were grouped based on the summating potential/action potential (SP/AP) ratio, and the amplitudes of AP and SP were compared between the two resulting groups. Second, 188 ears were divided into two groups: the normal SP/AP and abnormal SP/AP groups. The speech recognition abilities in the two groups were compared. Finally, the relationship between abnormal electrocochleogram and poor speech recognition (signal-to-noise ratio loss ≥7 dB) was analyzed in 188 ears. The results of the present study showed: (1) a remarkable reduction in the action potential amplitude was observed in patients with abnormal SP/AP ratios; this suggests that cochlear synaptopathy was involved in presbycusis. (2) There was a large proportion of patients with poor speech recognition in the abnormal SP/AP group. Furthermore, a larger number of cases with abnormal SP/AP ratios were confirmed among patients with presbycusis and poor speech recognition. We concluded that cochlear synaptopathy is not uncommon among elderly individuals who have hearing ability deficits, and it may have a more pronounced effect on ears with declining auditory performance in noisy environments.

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Neural Transformation of Dissonant Intervals in the Auditory Brainstem

Music Perception An Interdisciplinary Journal ◽

10.1525/mp.2015.32.5.445 ◽

2015 ◽

Vol 32 (5) ◽

pp. 445-459 ◽

Cited By ~ 4

Author(s):

Kyung Myun Lee ◽

Erika Skoe ◽

Nina Kraus ◽

Richard Ashley

Keyword(s):

Auditory System ◽

Auditory Processing ◽

Response Spectrum ◽

Phase Locking ◽

Auditory Pathway ◽

Auditory Brainstem ◽

Neural Representation ◽

Auditory Brainstem Responses ◽

Distortion Products ◽

Stimulus Waveform

Acoustic periodicity is an important factor for discriminating consonant and dissonant intervals. While previous studies have found that the periodicity of musical intervals is temporally encoded by neural phase locking throughout the auditory system, how the nonlinearities of the auditory pathway influence the encoding of periodicity and how this effect is related to sensory consonance has been underexplored. By measuring human auditory brainstem responses (ABRs) to four diotically presented musical intervals with increasing degrees of dissonance, this study seeks to explicate how the subcortical auditory system transforms the neural representation of acoustic periodicity for consonant versus dissonant intervals. ABRs faithfully reflect neural activity in the brainstem synchronized to the stimulus while also capturing nonlinear aspects of auditory processing. Results show that for the most dissonant interval, which has a less periodic stimulus waveform than the most consonant interval, the aperiodicity of the stimulus is intensified in the subcortical response. The decreased periodicity of dissonant intervals is related to a larger number of nonlinearities (i.e., distortion products) in the response spectrum. Our findings suggest that the auditory system transforms the periodicity of dissonant intervals resulting in consonant and dissonant intervals becoming more distinct in the neural code than if they were to be processed by a linear auditory system.

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