A influência das curvas timpanométricas nos resultados das emissões otoacústicas / The influence of tympanometric curves on the results of otoacoustic emissions

RESUMO Objetivo Analisar as emissões otoacústicas evocadas produto de distorção (EOAPD) de indivíduos adultos entre 18 e 50 anos, com audição normal, e associar os resultados com os achados à timpanometria. Métodos Foram selecionados 27 prontuários de adultos com audição dentro dos padrões de normalidade, sem queixa auditiva, com curva timpanométrica do tipo A, Ad ou Ar, presença de reflexos acústicos, sem queixa de zumbido e de exposição frequente a níveis de pressão sonora elevados, com repouso auditivo mínimo de 14 horas no momento do exame e que realizaram o exame de emissões otoacústicas evocadas produto de distorção. Os resultados do exame de emissões otoacústicas foram analisados considerando os resultados das curvas timpanométricas apresentadas por estes indivíduos. Para análise dos dados foram aplicados testes não paramétricos e o nível de significância foi de 5%. Resultados foram analisados os resultados das emissões otoacústicas de 54 orelhas. Observou-se maior ocorrência da curva do tipo A em indivíduos sem queixas auditivas. Independente do lado, a maioria das orelhas que apresentou resposta presente ao exame de EOAPD, apresentou, também, curva timpanométrica normal. Observou-se correlação positiva entre a amplitude das EOAPD e o volume da orelha média para as frequências de 6000 Hz e uma tendência à significância em 4000 Hz Conclusão Foi possível concluir que há maior ocorrência de emissões otoacústicas presentes em indivíduos com audição normal e curva timpanométrica do tipo A e que a amplitude das EOAPD em 6000 Hz mostra-se menor nos indivíduos com audição normal e curva timpanométrica do tipo Ar ou Ad.

ABSTRACT Purpose To analyze distortion product evoked otoacoustic emissions in normal-hearing adults aged between 18 and 50 years old, and to associate the results with the findings of tympanometry. Methods 27 medical records were selected of adults with the following conditions: normal hearing; without auditory complaint; with type A, Ad or Ar tympanometric curve; with presence of acoustic reflexes; with no complaint of tinnitus or frequent exposure to high sound pressure levels; with minimal auditory rest of 14 hours at the time of the test, and who had undergone distortion product evoked otoacoustic emission (DPOAE) testing. The results of otoacoustic emissions were analyzed considering the results of the tympanometric curves presented by these individuals. For the data analysis, non-parametric tests were applied, and the level of significance was 5%. Results The results of otoacoustic emissions of 54 ears were analyzed. There was a greater occurrence of the type A curve in individuals without auditory complaints. Regardless of side, most ears whose response was present in the DPOAE test also presented normal tympanometric curve. There was a positive correlation between DPOAE amplitude and middle ear volume for the 6000Hz frequencies (p = 0.048) and a tendency to significance at 4000Hz (p = 0.054). Conclusion There was a higher occurrence of otoacoustic emissions present in normal-hearing individuals and type A tympanometric curve, and the amplitude of DPOAE at 6000Hz was smaller in normal-hearing individuals and type Ar or Ad tympanometric curve.

Effects of nasal cavity ventilational function at low temperature plasma ablation and lateral fracture in treatment for nasal spetum deviation with chronic hypertrophic rhinitis / 临床耳鼻咽喉头颈外科杂志

Objective:To observe the outward flow of low temperature plasma ablation combined inferior turbinate fracture treatment for chronic hypertrophic rhinitis nasal ventilation function. Method:NR6 nasal resistance meter and A1 nasal sound reflection instrument were used to test 40 patients of Hypertrophic rhinitis nasal septum deviation merger before and after operation for one year, recording the nasal airway resistance,0 to 5 cm nasal cavity volume and the nasal minimum cross-sectional area, combine visual analog scale to analyze the changing parameter value, and to analyze the test values between the correlation. Result:Postoperative patients of NCV, NMCA, NS value was higher than that of preoperative, VAS, NAR value compared with preoperative lower (P<0.05); Postoperative VAS was negatively correlated with NCV, NMCA, NS (r=0.472, 0.698, 0.586, P<0.05); VAS was positively related with NAR (r=0.877, P<0.05); Postoperative NAR was negatively correlated with NCV, NMCA and NS (r=-0.464, -0.870, -0.707, P<0.05); there was a positive correlation between postoperative NS and NCV, NMCA (r=0.442, 0.741, P<0.05). Conclusion:On the deflection of nasal septum (lighter, smaller scale, the part of the deflection of a back with no obvious compressive deformation and lateral deflection of inferior turbinate) in patients with chronic hypertrophic rhinitis, low temperature plasma ablation combined offshoring inferior turbinate fracture surgery can effectively improve the nasal ventilation function, there is a good correlation between postoperative test values.

Relação entre os achados do teste masking level difference e do reflexo acústico em crianças com transtorno fonológico / Relationship between masking level difference test and acoustic reflex findings in children with phonological disorder

Resumo:OBJETIVO:investigar os achados do teste Masking Level Difference com os resultados do reflexo acústico e a composição do sistema fonológico de crianças com transtorno fonológico, com o propósito de verificar se há associações que possam auxiliar a compreensão do processo de aquisição de linguagem atípica.MÉTODOS:estudo quantitativo, observacional e descritivo, desenvolvido por meio de levantamento secundário de um banco de dados, constituído de avaliações fonoaudiológicas de 110 crianças com transtorno fonológico, com idades entre 5 e 10 anos. Para a composição do corpus deste estudo o requisito utilizado foi a realização da timpanometria, com curva timpanométrica do tipo A (Jerger) e possuir avaliação do Masking Level Difference.RESULTADOS:dos dados de 110 crianças, 57 se enquadraram nestes requisitos, compondo a população deste estudo, sendo 42 do sexo masculino e 15 do sexo feminino. Destas 57 crianças, 23 (40,3%) apresentam resultado do Masking Level Difference normal e 34 (59,7%) apresentam resultado alterado. Não foi encontrada diferença estatística na relação entre o Masking Level Difference com as variáveis idade, sexo, grau de inteligibilidade de fala e o resultado do reflexo acústico contralateral e ipsilateral. Na relação entre a aquisição fonológica dos fonemas em onsetinicial e medial, foi encontrada significância estatística entre a não aquisição dos fonemas /s/ e /ʀ/ em onset inicial e /s/ e /z/ em onset medial com o resultado do teste alterado.CONCLUSÃO:outras habilidades do processamento auditivo, além da interação binaural, devem ser estudadas a fim de identificar a relação deste com o transtorno fonológico.

Abstract:PURPOSE:to investigate the findings of Masking Level Difference and acoustic reflex tests along with the composition of the phonological system of children with Phonological Disorder, to determine whether these associations can assist in understanding the process of acquisition of atypical language.METHODS:a quantitative, observational and descriptive study, developed through secondary survey of a database, consisting of speech therapy evaluations of 110 children with Phonological Disorder, ages 5 - 10 years. The inclusion criteria for this study required all prospective subjects to have undergone tympanometry with type A (Jerger) tympanogram as well as a Masking Level Difference test evaluation.RESULTS:data from 110 children, 57 suited inclusion criteria, population composition: (42 male and 15 female). Of the 57 children, 23 (40.3%) had normal Masking Level Difference results and 34 (59.7%) had altered results. The relationship between the Masking Level Difference test and the variables age, sex, degree of speech intelligibility, and the result of contralateral and ipsilateral acoustic reflex were not observed to be statistically significant. The relationship between phonological acquisition of the phonemes in initial and medial onset with the results of the Masking Level Difference test was found to be statistically significant with the non-acquisition of both early-onset phonemes / s / and /ʀ/ and /s/ e /z/ in medial onset observed in subjects with altered Masking Level Difference test results.CONCLUSION:other auditory processing abilities beyond the binaural interaction should be studied in order to identify their association with phonological disorder.

Effect of contralateral stimulation on acoustic reflectance measurements / Efeito da estimulação contralateral nas medidas de reflectância acústica

ABSTRACT INTRODUCTION: Acoustic reflectance is an important tool in the assessment of middle ear afflictions, and the method is considered advantageous in relation to tympanometry. There has been a growing interest in the study of contralateral acoustic stimulation and its effect on the activation of the efferent auditory pathway. Studies have shown that the introduction of simultaneous stimulation in the contralateral ear generates alterations in auditory response patterns. OBJECTIVE: To investigate the influence of contralateral stimulation on acoustic reflectance measurements. METHODS: Case study of 30 subjects with normal hearing, of both genders, aged 18-30 years. The test and retest acoustic reflectance was conducted in the frequency range 200-6000 Hz. The procedure was repeated with the simultaneous presence of contralateral white noise at 30 dBNS. RESULTS: The analysis of the conditions of test, retest, and test with contralateral noise showed statistical difference at the frequency of 2 kHz (p = 0.011 and p = 0.002 in test and retest, respectively) in the right ear. CONCLUSION: The activation of the auditory efferent pathways through contralateral acoustic stimulation produces alterations in response patterns of acoustic reflectance, increasing sound reflection and modifying middle ear acoustical energy transfer.

RESUMO Introdução: A reflectância acústica é citada como uma importante ferramenta na avaliação das afecções da orelha média, sendo um método considerado vantajoso em relação à timpanometria. Tem havido crescente interesse no estudo da estimulação acústica contralateral e seu efeito na ativação da via eferente auditiva. Estudos têm demonstrado que a introdução de estímulo simultâneo na orelha contralateral gera mudanças no padrão de respostas auditivas. Objetivo: Verificar a influência da estimulação contralateral nas medidas de reflectância acústica. Método: Estudo de casos de 30 sujeitos com audição normal, de os gêneros entre 18 a 30 anos. Foi realizado o teste e reteste de reflectância acústica no intervalo de frequência de 200 a 6000 Hz. O procedimento foi repetido com a presença simultânea de ruído branco contralateral à 30 dBNS. Resultados: A análise entre as condições de teste, reteste e teste com ruído contralateral apresentou diferença estatística na frequência de 2 kHz (p = 0,011 em teste e p = 0,002 em reteste) em orelha direita. Conclusão: A ativação da via auditiva eferente por meio da estimulação acústica contralateral produz mudanças nos padrões de respostas da reflectância acústica, aumentando a reflexão do som e, modificando a transferência de energia sonora da orelha média.

Middle ear impedance studies in elderly patients implications on age-related hearing loss / Estudos de impedância da orelha média em pacientes idosos: implicações na perda auditiva relacionada à idade

INTRODUCTION: Controversies arise with respect to functioning of the middle ear over time. OBJECTIVE: To assess changes in middle ear impedance that may be related to aging, and/or if there was an association of these changes with those of the inner ear in the elderly patients. METHODS: Cross-sectional, comparative study of elderly patients managed in ear, nose and throat clinics. A structured questionnaire was administered to obtain clinical information. Pure tone audiometry, tympanometry, and acoustic reflexes were performed. Comparative analyses were performed to detect intergroup differences between clinico-audiometric findings and middle ear measures, viz. tympanograms and acoustic reflexes. RESULTS: One hundred and three elderly patients participated in the study; 52.4% were male, averagely 70.0 ± 6.3 years old, age-related hearing loss in 59.2%, abnormal tympanograms in 39.3%, absent acoustic reflex in 37.9%. There was no association between age and gender in patients with abnormal tympanograms and absent acoustic reflex. Significantly more patients with different forms and grades of age-related hearing loss had abnormal tympanometry and absent acoustic reflex. CONCLUSION: Some abnormalities were observed in the impedance audiometric measures of elderly patients, which were significantly associated with parameters connected to age-related hearing loss. .

INTRODUÇÃO: Existem controvérsias no que se refere às alterações funcionais da orelha média com o passar dos anos. OBJETIVO: Avaliar as mudanças na impedância da orelha média que podem estar relacionadas ao envelhecimento, bem como qualquer associação dessas alterações com as que ocorrem na orelha interna. MÉTODO: Estudo prospectivo comparativo de pacientes idosos atendidos em ambulatórios espe-cializados em otorrinolaringologia e aplicação de questionário estruturado para obtenção de informações clínicas. Foram realizadas audiometria de tons puros, timpanometria e reflexos acústicos e análise comparativa para detectar as diferenças intergrupos entre os achados clínico-audiométricos. RESULTADOS: Participaram do estudo 103 pacientes idosos: 52,4% do gênero masculino; idade de70 ± 63 anos; perda auditiva relacionada à idade detectada em 59,2%; timpanograma anormal em 39,3%; e reflexo acústico ausente em 37,9%. Não foi encontrada associação entre idade e gênero em pacientes com timpanograma anormal e reflexo acústico ausente. Um número significantemente maior de pacientes com diferentes graus e configurações de perda auditiva relacionada à idade apresentou timpanometria anormal e reflexo acústico ausente. CONCLUSÃO: Algumas anormalidades foram observadas em medidas de impedância audiométrica em pacientes idosos, que foram significantemente associados com os parâmetros ligados à perda auditiva relacionada à idade. .

Relação entre ausência do reflexo do músculo estapédio e presença de distúrbios do processamento auditivo (central) / The relationship between the lack of stapedial muscle reflex and the presence of (central) auditory processing disorders

Objetivo caracterizar e relacionar os achados do reflexo acústico do músculo estapédio em indivíduos com diagnóstico de distúrbios do processamento auditivo (central). Métodos pesquisa transversal descritiva retrospectiva, submetida e aprovada pelo Comitê de Ética em Pesquisa, sob o protocolo nº 0047/11. Amostra constituiu-se de 83 prontuários de indivíduos de ambos os gêneros (57 masculino e 26 feminino) que apresentaram alteração na avaliação do processamento auditivo (central) associada à ausência do reflexo acústico. Resultados e Discussão os resultados demonstraram numericamente que as frequências com maior número de ausência do reflexo acústico, tanto na pesquisa contralateral quanto na ipsilateral, foram 4KHz, 3KHz e 500Hz respectivamente, para ambos os gêneros, mas, sem diferença significante no tratamento estatístico. Também, em ambos os grupos, as habilidades auditivas que apresentaram maior frequência de alterações foram figura fundo e ordenação temporal, que sobressaíram em número quando comparadas com as demais habilidades, e sem diferença significante no tratamento estatístico realizado com os testes de Fisher, Quiquadrado e Anova. Conclusão os resultados da presente pesquisa nos levam a concluir que as estruturas do sistema nervoso auditivo central responsáveis pelo sistema do arco reflexo do músculo estapédio, também relacionam-se aos mecanismos fisiológicos auditivos das habilidades auditivas, o que evidencia a possível relação entre a ausência do RA com alterações do distúrbio do processamento auditivo (central). .

Purpose to characterize and relate the findings of the acoustic reflex of the stapedial muscle in individuals diagnosed with Auditory Processing Disorder. Methods descriptive retrospective cross-sectional research submitted and approved by the Ethics in Research Committee, under protocol number 0047/11. The sample consisted of 83 individuals (57 males and 26 females), who showed abnormalities in auditory processing associated with the absence of acoustic reflex. Results and Discussion the results showed that the frequencies which lack more in the acoustic reflex both in the ipsilateral and in contralateral research were 4000 Hz, 3000 Hz and 500 Hz, respectively for both, but without significant difference in the statistical analysis. Also, in both groups the auditory skills which presented more change frequency were the speech in noise and temporal ordering which called the attention to their number when compared to other skills without significant difference in the statistical analysis performed by the Fisher, chi-square and ANOVA tests. Conclusion with shown results we can conclude that the nervous system structures for the central hearing are responsible for the bridge reflex system of the stapedial muscle, which also relate to the acoustic physiologic of the auditory skills which shows a possible relation to the lack of RA to the changes of the disorder of the (central) auditory processing .

Time Course of the Suppression Effect on Transient Evoked Otoacoustic Emissions by Prolonged Contralateral Acoustic Stimulation

BACKGROUND AND OBJECTIVES: Although the suppressive effect of the medial efferent acoustic reflex is well known, the time course of this effect over prolonged periods has yet to be fully evaluated. We assessed time-dependent change in the suppression of transient evoked otoacoustic emissions (TEOAEs) by the medial efferent acoustic reflex over a relatively long period. SUBJECTS AND METHODS: We measured TEOAEs in the right ear before contralateral acoustic stimulation (CAS), and then measured serial TEOAEs in the right ear at four intervals during a total of 16 minutes of continuous CAS, followed by three more recordings after termination of CAS. RESULTS: TEOAE amplitudes were reduced with CAS during a certain period (from the immediate period to 10 minutes depending on frequency) and subsequently recovered. TEOAE suppression values in the mean amplitudes for overall frequency were 0.76 dB at the initial recording, 0.35 dB at 5 minutes, 0.44 dB at 10 minutes, and 0.33 dB at 15 minutes during CAS. The initial suppression value was significantly larger than other suppression values of 5, 10, and 15 minutes (p<0.05). In recordings obtained after CAS, TEOAE amplitude exceeded pre-acoustic amplitudes at 1 kHz, 1.5 kHz, and 2 kHz. CONCLUSIONS: The present results show the existence of the medial efferent acoustic reflex and demonstrate the time course that TEOAE suppressions present initially after CAS, showing fatigue over time. Overshooting of TEOAE was observed in recordings at several frequencies after termination of CAS.

Time Course of the Suppression Effect on Transient Evoked Otoacoustic Emissions by Prolonged Contralateral Acoustic Stimulation

BACKGROUND AND OBJECTIVES: Although the suppressive effect of the medial efferent acoustic reflex is well known, the time course of this effect over prolonged periods has yet to be fully evaluated. We assessed time-dependent change in the suppression of transient evoked otoacoustic emissions (TEOAEs) by the medial efferent acoustic reflex over a relatively long period. SUBJECTS AND METHODS: We measured TEOAEs in the right ear before contralateral acoustic stimulation (CAS), and then measured serial TEOAEs in the right ear at four intervals during a total of 16 minutes of continuous CAS, followed by three more recordings after termination of CAS. RESULTS: TEOAE amplitudes were reduced with CAS during a certain period (from the immediate period to 10 minutes depending on frequency) and subsequently recovered. TEOAE suppression values in the mean amplitudes for overall frequency were 0.76 dB at the initial recording, 0.35 dB at 5 minutes, 0.44 dB at 10 minutes, and 0.33 dB at 15 minutes during CAS. The initial suppression value was significantly larger than other suppression values of 5, 10, and 15 minutes (p<0.05). In recordings obtained after CAS, TEOAE amplitude exceeded pre-acoustic amplitudes at 1 kHz, 1.5 kHz, and 2 kHz. CONCLUSIONS: The present results show the existence of the medial efferent acoustic reflex and demonstrate the time course that TEOAE suppressions present initially after CAS, showing fatigue over time. Overshooting of TEOAE was observed in recordings at several frequencies after termination of CAS.

Change of Stapedial Reflex Threshold according to the Depth of Intravenous Propofol Anesthesia / 대한이비인후과학회지

BACKGROUND AND OBJECTIVES: Stapedial reflex (SR) threshold is of considerable diagnostic significance in the evaluation of audiological function, especially under sedation or general anesthesia since anesthetic drugs often act on neurotransmitters or neuromodulators. The aim of this study was to evaluate the changes in the SR threshold according to the depth of anesthesia. SUBJECTS AND METHOD: Sixty patients with normal hearing who were scheduled for operation under general anesthesia were included in this study. Anesthetic agent used was propofol and the depth of anesthesia was monitored by the bispectral index (BIS). SR was measured five times according to depth of anesthesia. RESULTS: Both ipsilateral and contralateral SR thresholds were increased according to the depth of anesthesia using propofol. In particular, ipsilateral SR showed no response at BIS 60 and contralateral SR at BIS 40. However, there were no significant differences between age groups and gender. CONCLUSION: Propofol significantly increased both ipsilateral and contralateral SR threshold according to depth of anesthesia. When it is necessary to measure SR under general anesthesia, we should consider the effect on SR threshold according to the depth of anesthesia.

Medidas imitanciométricas em crianças com ausência de emissões otoacústicas / Acoustic immittance in children without otoacoustic emissions

Partindo da hipótese de que alterações da função de orelha média possam prejudicar a captação das EOAs, é possível que a ausência destas, em lactentes, esteja associada a discretas alterações timpanométricas. OBJETIVO: Verificar a associação entre resposta de EOAT e alteração imitanciométrica com a sonda de 226Hz em lactentes. MÉTODOS: Estudo de coorte contemporânea com corte transversal. Foram avaliados 20 lactentes com ausência de EOAT (grupo pesquisa) e 101 lactentes com presença de EOAT (grupo comparação), com idades variando entre o nascimento e oito meses. Os lactentes foram submetidos a: timpanometria; pesquisa dos limiares de reflexo acústico contralateral com estímulos de 0,5k, 1k, 2k, 4kHz e ruído de faixa larga; emissões otoacústicas (transiente e por produtos de distorção). O potencial evocado auditivo de tronco encefálico para pesquisa do limiar de resposta foi realizado no grupo pesquisa. RESULTADOS: Observou-se diferença estatisticamente significante entre os grupos (p<0,05), caracterizada pela redução na altura timpanométrica e aumento do limiar de reflexo acústico no grupo pesquisa e a ocorrência de discreto comprometimento de orelha média, no grupo pesquisa, associada às respostas eletrofisiológicas normais. CONCLUSÃO: O uso combinado da timpanometria e do reflexo acústico, em lactentes, acrescenta precisão no diagnóstico de alteração de orelha média.

Considering the hypothesis that middle ear changes can impair the recording of otoacoustic emissions, it is possible that absent otoacoustic emissions in infants could be associated with a light tympanometric change. AIM: To study the association between transient otoacoustic emissions and changes in acoustic immittance measurements with 226Hz probe tone in neonates. METHODS: Cross-sectional contemporary cohort study. 20 infants with no transient otoacoustic emissions (study group) and 101 infants with transient otoacoustic emissions (control group), with ages ranged from birth to eight months, were assessed. Infants were submitted to: admittance tympanometry; contralateral acoustic reflex threshold with stimulus of 0.5, 1, 2, 4 kHz and broad band noise; transient and distortion product otoacoustic emissions. The auditory brain response was used to study the threshold in neonates without transient otoacoustic emissions. RESULTS: Significant statistical differences were observed between the groups (p < 0.005), characterized by reduction in tympanometric configuration and increase acoustic reflex thresholds in the study group. These data suggest the occurrence of middle ear mild impairment in infants without transient otoacoustic emissions associated with normal auditory brain response. CONCLUSION: tympanometry associated with acoustic reflex adds accuracy to the diagnosis of middle ear abnormalities.

Supressão das emissões otoacústicas e sensibilização do reflexo acústico no distúrbio de processamento auditivo / Otoacoustic emission suppression and acoustic reflex sensitization in auditory processing disorders

INTRODUÇÃO: O processamento da informação sonora depende da integridade das vias auditivas. O sistema auditivo eferente pode ser avaliado por meio de dois métodos objetivos e não-invasivos: a obtenção dos limiares dos reflexos acústicos, e a supressão das emissões otoacústicas. OBJETIVO: Verificar a atividade do sistema auditivo eferente, por meio da supressão das emissões otoacústicas por transientes (EOAT) e da sensibilização do reflexo acústico em indivíduos com alteração de processamento auditivo. MÉTODO: Foram avaliadas 50 crianças com alteração de processamento auditivo (grupo estudo) e 38 crianças sem alteração de processamento auditivo (grupo controle), por meio das EOAT evocadas por "clicks" na ausência e na presença de ruído ipsilateral e contralateral, e por " tone bursts", nas frequências de 1000, 2000 e 4000 Hz na ausência e na presença de ruído contralateral, e de reflexo acústico nas frequências de 500, 1000, 2000 e 4000 Hz na ausência e na presença de estímulo facilitador ipsi e contralateral. RESULTADOS: O valor da média de EOAT evocadas por "clicks" com estímulo supressor foi de até 1,50 dB para o grupo controle e de até 1,26 dB para o grupo estudo. Para as EOAT evocadas por "tone bursts" com estímulo supressor, os valores médios foram de até 2,69 dB para o grupo controle e de até 2,79 dB para o grupo estudo. Foi observado efeito de sensibilização do reflexo acústico com redução média de até 18,17 dB para o grupo estudo e de até 17,38 dB para o grupo controle. Não foi observada diferença estatisticamente significante entre as respostas do grupo controle e do grupo estudo, para supressão de EOAT (exceto na frequência de 2000 Hz - "tone burst"), e para sensibilização do reflexo acústico. CONCLUSÕES: O grupo estudo apresentou valores reduzidos na pesquisa de supressão das EOAT e valores aumentados na sensibilização do reflexo acústico, em relação ao grupo controle.

INTRODUCTION: Auditory processing depends on the auditory pathways integrity. Efferent auditory system may be assessed in humans by two non-invasive and objective methods: acoustic reflex and otoacoustic emissions suppression. OBJECTIVE: Analyze efferent auditory system activity by otoacoustic emissions suppression and acoustic reflex sensitization in human subjects with auditory processing disorders. METHOD: Fifty children with auditory processing disorders (study group) and thirty-eight children without auditory processing disorders (control group) have being evaluated using clicks otoacoustic emission suppression with and without ipsilateral and contralateral white noise; tone bursts otoacoustic emission suppression in 1000, 2000 and 4000 Hz with and without contralateral white noise and acoustic reflex in 500, 1000, 2000 and 4000 Hz with and without ipsilateral and contralateral facilitator. RESULTS: The higher clicks otoacoustic emission suppression was up to 1.50 dB for the control group and up to 1.26 dB for the study group. The higher tone burst otoacoustic emission was up to 2.69 dB for the control group and up to 2.79 dB for the study group. The higher acoustical reflex sensitization was up to 18.17 dB for the study group and up to 17.38 dB for the control group. There was no significant statistical difference between results for control group and study group to otoacoustic emission suppression (except for 2000 Hz) and acoustical reflex sensitization. CONCLUSION: Study group presented smaller otoacoustic emission suppression than control group and study group presented higher acoustical reflex sensitization than control group.

Acoustic Reflex Growth Function in Noise Induced Hearing Loss / 听力学及言语疾病杂志

Objective To explore the effects of noise exposure on acoustic reflex growth function (ARGF).Methods 106 ears of 57 industrial workers that exposed to high level continuous noise during their work day were divided into three groups according to pure-tone threshold average (PTA): normal hearing group, mild hearing loss group and moderately severe hearing loss group. The control group consisted of 50 ears of 25 young persons with normal hearing. The contralateral acoustic reflex thresholds (ART) were obtained from all individuals.1 000 Hz pure-tone stimuli was wsed to elicit the acoustic reflex at hearing levels from ART to 125 dB in 5 dB steps during ascending intensity level runs. The growth functions were observed as changes in acoustic reactance with increases in activator-signal intensity level.Results The noise exposed groups had smaller acoustic reflex dynamic ranges, smaller acoustic reactance growth magnitudes and shallow slopes compared with those of the control group. Data showed that there were significant differences among the control and the noise exposed groups (P0.05).Conclusion The influence of noise exposure on ARGF is significant. The results of this study suggest that ARGF could be used in the monitoring of the noise-induced hearing loss as an indicator of subtle alterations of the hearing function.

Acoustic Reflex Facilitation with Various Frequencies and Amplitudes of Pure Tone / 대한이비인후과학회지

BACKGROUND AND OBJECTIVES: There are several methods for lowering the acoustic reflex hreshold, a process known as "facilitaion". The most popular facilitation method is the simultaneous stimulation of a high-frequency tone (facilitator) with a reflex-elicing tone (activator). This study was performed in order to analyze and generalize the facilitation phenomenon, and infer clinical applications from this phenomenon. MATERIALS AND METHODS: Authors measured the acoustic reflex thresholds when the facilitators of various amplitudes and frequencies was simultaneously stimulated in normal population. Also, the effects of facilitation was observed on the growth function curve (a curve showing the acoustic reflex pattern in subthreshold and suprathreshold stimulation). RESULTS: Facilitation was observed more effectively by using facilitators of high frequencies and high amplitudes. In the analysis of growth function curve, we found similar result as above. But there was no correlation between the frequency of activator and the mode of facilitation. CONCLUSION: We analyzed the factors affecting the phneomenon of facilitation and discussed a several proposals explaining the different tendencies of facilitation. Further studies should be made on the clinical implication of this phenomenon to sensorineurally hearing-impaired patients or children.

Test-Retest Differences and Assistive Function in Detecting Conductive Hearing Loss of lmpedance Audiometry

lmpedance audiometry requires physical modifications during the test, which might influence retest data. Therefore, in Order to interprete retest data meaningfully, the range of variation should be identified in each measure of impedence audiometry. The present study obtained data on the retest variation of peak pressure, acoustic reflex threshold, static compliance and earcanal volume in impedance audiometry. ln addition, the authors wanted to know whether or not impedance data would assist otolaryngologists in the detection of conductive hearing impairment. The variation of the retest data was not clinically nor statistically significant in the measurement except for those of ear canal volume. The data on ear canal volume also suggested that the ear canal increases in size during the teenage period and that male ear canals are larger than those of females in ears over 20 years of age. The impedance data assisted the otolaryngologist in the detection of conductive hearing impairment