oalib

OALib Journal期刊

ISSN: 2333-9721

费用：99美元

投稿

时间不限

( 2026 )

( 2025 )

( 2024 )

( 2023 )

自定义范围…

匹配条件： “distortion-product otoacoustic emissions” ，找到相关结果约1000条。
列表显示的所有文章，均可免费获取
第1页/共1000条
每页显示 条
Distortion-product otoacoustic emissions: body position effects with simultaneous presentation of tone pairs
Samuel R. Atcherson,Amy Mattheis
Audiology Research , 2011, DOI: 10.4081/audiores.2011.e29
Abstract: This study examined the effect of three different body positions on distortion-product otoacoustic emission (DPOAE) amplitude and noise levels with multiple primary tone pairs simultaneously-presented to 36 normal-hearing female human adults. Other studies have demonstrated that the simultaneously presented tone pairs method shows clinical promise as a screener, but the sequential method remains in widespread clinical use. Postural changes have been suggested to have an effect not only on DPOAEs, but also transient-evoked OAEs and stimulus- frequency OAEs. DPOAE amplitude and noise levels were recorded in seated, supine, and side-lying positions to the following order of simultaneously-presented tone pairs relative to the f2 frequencies: 1187, 2375, and 4812 Hz; 1500, 3000, and 6062 Hz; and 1875, 3812, and 7625 Hz. No DPOAE could be detected reliably at 7625 Hz as result of poor signal-to-noise ratio. For remaining DPOAEs, statistical analyses revealed that amplitudes were not significantly different among the three body positions. However, at 1500 Hz and below, body position did have a statistically significant effect on noise levels though they are likely clinically negligible. Except at 7625 Hz, results suggest that DPOAEs recorded using a simultaneously presented tone pairs appear to be comparably recorded regardless of an individual’s body position.
Emiss？es otoacústicas por produtos de distor？？o em ovinos normais e após indu？？o de hiperinsulinemia
Maia, Francisco Carlos Zuma e;Lavinsky, Luiz;M？llerke, Roseli Oliveira;Duarte, Marcos Eugenio Soares;Pereira, Daniela Peres;Maia, Juliana Elert;
Revista Brasileira de Otorrinolaringologia , 2008, DOI: 10.1590/S0034-72992008000200005
Abstract: transient evoked otoacoustic emissions and distortion product otoacoustic emissions have gained significant importance in the identification of cochlear alterations. aim: to record distortion product thresholds through the monitoring of otoacoustic emissions in normal conditions and in the presence of electrophysiologic changes in cochlear outer hair cells in sheep after hyperinsulinemia induction. material and methods: experimental study, with seven sheep in the control group and seven in the study group. insulin and glucose concentrations were measured simultaneously for the recording of distortion product otoacoustic emission every 10 minutes, all the way to 90 minutes. the control group received saline solution, and the study group received a bolus injection of 0.1 u/kg of regular human insulin. results: there was a significant reduction in distortion product thresholds in the study group when compared to the control group at frequencies greater than 1,500hz and after 60 minutes (p < 0.001). conclusion: this study established distortion product otoacoustic emission thresholds in sheep with constant reproducibility, demonstrating that the method is adequate for use in audiology and otology investigations. results also fully confirm that acute hyperinsulinemia may cause important changes in these thresholds.
Emiss？es otoacústicas evocadas - produto de distor？？o em neonatos audiologicamente normais
Raineri, Gláucia G.;Coube, Carmen Z. V.;Costa Filho, Orozimbo A.;Alvarenga, Kátia F.;
Revista Brasileira de Otorrinolaringologia , 2001, DOI: 10.1590/S0034-72992001000500007
Abstract: introduction: distortion product otoacoustic emissions (dpoae) researches on neonates shed a new light into early diagnosis of sensorial hearing losses. study design: prospective results clinical not randomized. aim: the purpose of the present study was to typify dpoae in 20 normal hearing neonates of both sex, according to occurrence, amplitude and duration of test, through dp-gram and utilizing ilo 92 oae system-otodynamics analyzer. results: seventeen out of twenty neonates who volunteered for the research were evaluated, totaling 33 ears. dpoae occurred in 57.5% in 1 khz; 93.9% in 1.5 khz and 3 khz; 96.9% in 2 khz and 100% in 4 khz and 6 khz. conclusion: the dpoae average amplitude fluctuated from 9.9 to 20.3 db spl. the average duration of the test was 82 seconds.
Estudo da reprodutibilidade das emiss？es otoacústicas em indivíduos normais
Guedes, Mariana C.;Passos, Simone N.;Gomez, Maria Valéria S. Goffi;Bento, Ricardo Ferreira;
Revista Brasileira de Otorrinolaringologia , 2002, DOI: 10.1590/S0034-72992002000100006
Abstract: introduction: some studies report the importance of the cochlear function monitoring when dealing with patients exposed to ototoxic drugs or agents. a lot of research about test-retest reliability of the otoacoustic emissions was done to validate its use on cochlear monitoring. nevertheless, our clinical experience shows us that the measured variations differ from those described in the literature. aim: verify the variation of the transient evoked otoacoustic emissions and the distortion product otoacoustic emissions. study design: clinical prospective randomized. material and method: we studied 10 normal hearing young adults, using the madsen, celesta 503 program. three serial evaluations were done, with a minimal interval of three weeks, maintaining variables such as olive size, number of sweeps and stimulus intensity controlled. results: showed that the transient evoked otoacoustic emissions amplitude varied less than distortion product otoacoustic emissions amplitude and that the amplitude of the initial response was not determinant in the amount of variability.
Study of Noise Effects on Rabbit's Hearing Status Using Distortion Product Otoacoustic Emissions
Seyyed Ali Moussavi-Najarkola,Ali Khavanin,Ramezan Mirzaee,Mojdeh Salehnia
Audiology , 2011,
Abstract: Background and Aim: Noise-induced hearing loss is the most common problem in industrial areas. This study aimed to determine effects of excessive noise exposure on measurable characteristics of distortion product otoacoustic emissions (DPOAEs) in rabbits.Methods: The study was carried out on 12 adult male New Zealand White rabbits including case group - exposed to 500-8000 Hz broadband white noise with 100 dBA SPL for 8 hours per day in 5 consecutive days - and control group. After three days period of acclimatization to the experimental condition, rabbits hearing status in each group were measured by distortion product otoacoustic emissions on days zero means before the study was initiated as a baseline, eight, one hour after the latest exposure to noise, and ten. The recorded results were analyzed using SPSS software.Results: Highest mean distortion product otoacoustic emissions amplitudes in case group were allocated to frequencies of 5888.50 Hz, 8166.50 Hz, 9855.00 Hz, 3956.00 Hz, and 3098.50 Hz, respectively. However, the lowest mean distortion product otoacoustic emissions amplitude was related to frequency of 588.00 Hz (p=0.001).Conclusion: This study revealed that distortion product otoacoustic emissions amplitude shifts due to noise occur first in high and then in middle frequencies. Additionally, exposure to noise can decrease distortion product otoacoustic emissions amplitudes. We conclude that distortion product otoacoustic emissions can be a reliable test for estimating personal susceptibility to noise-induced hearing loss.
Protective Effect of N-Acetylcysteine on the Hearing of Rabbits Exposed to Noise and Carbon Monoxide
Negin Salehi,Mehdi Akbari,Masoud Motalebi Kashani,Hamid Haghani
Audiology , 2011,
Abstract: Background and Aim: One of the chemical pollutions which is frequently common in industry-other than noise is carbon monoxide. The present study aimed to assess the putative protective effect of N-acetylcysteine on the function of outer hair cells of rabbits exposed simultaneously to noise and carbon monoxide.Methods: 24 male rabbits are entered in this interventional study. After obtaining baseline distortion product otoacoustic emissions, rabits were randomely devided into four groups. The groups Included: exposed with noise and received saline, exposed with noise and carbon monoxide and received saline, exposed with noise and received N-acetylcysteine, and exposed with noise and carbon monoxide and received N-acetylcysteine. Subsequently, they were evaluated again with distortion product otoacoustic emissions in two stages (two hours and one week after the exposure). Data were recorded and analyzed using paired and independent sample t-tests.Results: Exposure to noise, and also simultaneous exposure to noise and carbon monoxide, and moreover using N-acetylcysteine in both groups, produced significant changes in distortion product otoacoustic emissions amplitudes (p<0.005).Conclusion: The findings of the present research reveal that simultaneous exposure to noise and carbon monoxide may potentiate noise induced hearing loss. In addition, utilizing N-acetylcysteine can be used as a preventive agent for noise induced hearing loss and to avoid its potentiation with carbon monoxide.
Latência das EOAPD em milissegundos e número de ondas
Campos, Ualace de Paula;Carvallo, Renata Mota Mamede;
Revista Brasileira de Otorrinolaringologia , 2005, DOI: 10.1590/S0034-72992005000600016
Abstract: the latency of distortion product otoacoustic emissions is defined as the time interval between the wave onset from initial stimulation and the return to the ear canal. aim: the aim of this research was to verify the latency of the distortion product otoacoustic emissions in normal hearing adults, analyzing the influence of the gender, ear, frequencies and measurements. study design: clinical prospective. material and method: the measurements had been taken in milliseconds and waves. it was an experimental study, conducted at s？o paulo city in 2003. the sample consisted of 38 adults, 18 men and 20 women. significant differences for interactions between frequency, ear, gender and measurements were not observed in relation to the latency in milliseconds and waves. a high correlation between the latency measurements in milliseconds and waves was observed. it was concluded that the latency of distortion product otoacoustic emission diminishes as increases the frequency in milliseconds and the opposite occurs in waves. statistical differences in latencies of distortion product otoacoustic emission were not observed between gender, ears and measurements.
Contrasting Effects of Pressure Compensation on TEOAE and DPOAE in Children With Negative Middle Ear Pressure
Goran Trajkovi？,Helen Spencer,Mark P. Haggard,Snezana A. Filipovi？
- , 2018, DOI: 10.1177/2331216518812251
Abstract: In children with normal cochlear acuity, middle ear fluid often abolishes otoacoustic emissions (OAEs), and negative middle ear pressure (NMEP) reduces them. No convincing evidence of beneficial pressure compensation on distortion product OAE (DPOAE) has yet been presented. Two studies aimed to document effects of NMEP on transient OAE (TEOAE) and DPOAE. In Study 1, TEOAE and DPOAE pass/fail responses were analyzed before and after pressure compensation in 50 consecutive qualifying referrals having NMEP from ？100 to ？299？daPa. Study 2 concentrated on DPOAE, recording both amplitude (distortion product amplitude) and signal-to-noise ratio (SNR) before and after pressure compensation. Of the 20 participants, 5 had both ears qualifying. An effect of compensation on meeting a pass criterion was present in TEOAE for both left and right ear data in Study 1 but not demonstrable in DPOAE. In Study 2, the distortion product amplitude compensation effect was marginal overall, and depended on recording frequency band. SNR values improved moderately after pressure compensation in the two (overlapping) sets of single-ear data. In the five cases with both ears qualifying, a stronger compensation effect size, over 3？dB, was seen. The absolute dependence of SNR on frequency was also strongly replicated, but in no analysis, the frequency？×？compensation interaction was significant. Independent of particular frequency range, the data support a limited SNR improvement in 2 to 3？dB for compensation in DPOAE, with slightly larger effects in ears giving SNRs between 0？dB and +6？dB, where pass/fail cutoffs would generally be located
Otoacoustic Emissions and Their charactristics
Ghassem Mohammadkhani
Audiology , 2002,
Abstract: OAEs are sound founds in the external aditory meatus that originate in the cochlea. OAEs are generated only when the organ of corti is in near normal condition and They can be detected only when the middle ear system is operating normally. The sound generated by the cochlea are small but potentially audible, sometimes as much as 30 dBSPL. They can emerge spontaneously in the cochlea, but more commonly OAEs follow acoustic stimulation. No electrod are needed to observe OAEs. In fact, microphone are used to detect them.
Effect of drill-induced noise on hearing in non-operated ear
Alireza Fazel,Mehrdad Rogha,Mohamadhosein Nilforoush,Reza Solooki,Seyyed Hamidreza Abtahi
- , 2016, DOI: 10.4103/2277-9175.182218
Abstract: The aim of this study was to evaluate the effect of drill-generated noise on hearing loss in non-operated ear and if any, was temporary or persistent
第1页/共1000条
每页显示 条


Home
Copyright © 2008-2020 Open Access Library. All rights reserved.