Variación de los parámetros acústicos: f0, Jitter, Shimmer y Alpha ratio en relación con distintos niveles de ruido de fondo / Variation of the acoustic parameters: f0, Jitter, Shimmer and Alpha ratio in relation with different background noise levels

Antecedentes y objetivos: Las investigaciones que involucran el análisis acústico no siempre consideran el nivel de ruido de fondo del recinto donde van a realizar el proceso de grabación o si lo hacen el valor máximo de ruido de fondo que utilizan varía de autor en autor. El objetivo de esta investigación es determinar si los parámetros: f0, Jitter, Shimmer y Alpha ratio varían en relación con los distintos niveles de ruido de fondo del recinto donde se realiza la grabación, y determinar un valor máximo de este. Materiales y métodos Se utilizó el programa Praat® para obtener el valor promedio de los parámetros: f0, Jitter, Shimmer y Alpha ratio a partir de una muestra de voz en 33 sujetos al interior de una cabina Audiométrica cuyo nivel de ruido de fondo fue de 28,1dB(A). Se realizó una comparación estadística entre el valor promedio de cada parámetro al ir incrementando el nivel de ruido de fondo en relación con los valores promedio obtenidos con el nivel de ruido de fondo basal de la cabina para cada parámetro. Resultados Los parámetros f0 y Alpha ratio, muestran valores confiables hasta un nivel de ruido de fondo de 47,7dB(A), mientras que los parámetros Jitter y Shimmer lo hacen hasta un nivel de ruido de fondo de 43,8dB(A). Conclusiones Considerando que los parámetros acústicos se obtienen todos de la misma grabación, podemos señalar que el nivel de ruido de fondo máximo recomendable en el recinto donde se realicen las grabaciones debiese ser no superior a los 43,8dB(A). (AU)

Background and objectives: Research involving acoustic analysis does not always consider the level of background noise in the room where the recording process is going to be carried out, or if they do, the maximum value of background noise used varies from author to author. The objective of this research is to establish if the parameters: f0, Jitter, Shimmer and Alpha ratio vary in relation to different levels of background noise in the room where the recording process is carried out and to establish a maximum value of this. Materials and methods The Praat program was used to get the average value of the parameters: f0, Jitter, Shimmer and Alpha ratio from a voice sample of 33 subjects inside an audiometric booth whose background noise level was 28.1dB(A). A statistical comparison was made between the average value of each parameter as the background noise increased in relation to the average values obtained with the baseline background noise of the cabin for each parameter. Results The f0 and Alpha ratio parameters show reliable values up to a background noise level of 47.7dB(A), while the Jitter and Shimmer parameters do so up to a background noise level of 43.8dB(A). Conclusions Considering that the acoustic parameters are all obtained from the same recording, we can point out that the recommended maximum background noise level in the room where the recordings are made should not exceed 43.8dB(A). (AU)

Validation of a Bilateral Simultaneous Computer-Based Tympanometer.

Purpose This study aimed to investigate the accuracy of bilateral simultaneous tympanometric measurements using a tympanometer with two pneumatic systems inside circumaural ear cups. Method Fifty-two adults (104 ears), with a mean age of 32 years (SD = 12.39, range: 18-60 years) were included in this study. A within-subject repeated-measures design was used to compare tympanometric measurements yielded with the investigational device in unilateral and bilateral simultaneous conditions compared with an industry-standard tympanometer. Results No significant bias (p > .05) was found between the mean of the differences of tympanometric measurements yielded by the two devices, except for a significant bias (p < .05) of the mean of the differences for ear canal volume measurements (0.05 cm3). The Bland-Altman plots showed overall good agreement between the tympanometric measurements between the two instruments. In all 104 ears, the tympanogram types of the KUDUwave TMP were compared with the reference device. The results were highly comparable with a sensitivity and specificity of 100% (95% CI [86.8%, 100%]) and 92.3% (95% CI [84.0%, 97.1%]), respectively. Conclusions The investigational device is a suitable instrument for unilateral or bilateral simultaneous tympanometric measurements in adults and demonstrates the potential of decentralized and accessible tympanometry services.

A bench-top model of middle ear effusion diagnosed with optical tympanometry.

OBJECTIVES: To assess the validity of a bench-top model of an optical tympanometry device to diagnose in vitro model of middle ear effusion (MEE). METHODS AND MATERIALS: We illuminated an in vitro model of ear canal and tympanic membrane with broadband light and relayed remitted light to a spectrometer system. We then used our proprietary algorithm to extract spectral features that, together with our logistic regression classifiers, led us to calculate a set of simplified indices related to different middle ear states. Our model included a glass vial covered with a porcine submucosa (representing the tympanic membrane) and filled with air, water, or milk solution (representing different MEE), and a set of cover-glass slips filled with either blood (representing erythema) or cerumen. By interchanging fluid types and cover-glass slips, we made measurements on combinations corresponding to normal healthy ear and purulent or serous MEE. RESULTS: Each simulated condition had a distinct spectral profile, which was then employed by our algorithm to discriminate clean and cerumen-covered purulent and serous MEE. Two logistic purulent and serous MEE classifiers correctly classified all in vitro middle ear states with 100% accuracy assessed by leave-one-out and k-fold cross validation. CONCLUSIONS: This proof-of-concept in vitro study addressed an unmet need by introducing a device that easily and accurately can assess middle ear effusion. Future in vivo studies aimed at collecting data from clinical settings are warranted to further elucidate the validity of the technology in diagnosing pediatric acute otitis media.

Automated remote intraoperative cochlear implant device testing (CR220). Is it clinically efficient?

OBJECTIVES: To compare the clinical efficiency of the CR220 intraoperative remote assistant device used by the surgical team with that of the custom sound (CS) system used by an audiologist. METHODS: This was a prospective clinical study in a quaternary care center (King Abdullah Ear Specialist Centre) in Riyadh, Saudi Arabia, between October 2018 and March 2019. We included adult and pediatric patients who underwent cochlear implant (CI) surgeries. For every participant, the intraoperative CI testing was performed via both the aforementioned methods. The time taken to complete the measurements with both approaches, including the time required by the audiologist to reach the operating room (OR) and to complete the test, was recorded. RESULTS: There were no significant differences in the number of responding electrodes between the 2 approaches. For the 25 participants, the time taken for the measurements was 566 minutes with the CS and 173 with the CR220 systems. This significant difference indicates that considerable time can be saved. CONCLUSION: The CR220 enables intraoperative CI electrode tests and auto-NRT measurements. Its ergonomics and ease-of-use help the surgical team conduct the tests without an audiologist in the OR, resulting in the efficient use of clinical resources. Further, the results generated were consistent with those of the CS system.

A comparison of ear-canal-reflectance measurement methods in an ear simulator.

Ear-canal reflectance has been researched extensively for diagnosing conductive hearing disorders and compensating for the ear-canal acoustics in non-invasive measurements of the auditory system. Little emphasis, however, has been placed on assessing measurement accuracy and variability. In this paper, a number of ear-canal-reflectance measurement methods reported in the literature are utilized and compared. Measurement variation seems to arise chiefly from three factors: the residual ear-canal length, the ear-probe insertion angle, and the measurement frequency bandwidth. Calculation of the ear-canal reflectance from the measured ear-canal impedance requires estimating the ear-canal characteristic impedance in situ. The variability in ear-canal estimated characteristic impedance and reflectance due to these principal factors is assessed in an idealized controlled setup using a uniform occluded-ear simulator. In addition, the influence of this measurement variability on reflectance-based methods for calibrating stimulus levels is evaluated and, by operating the condenser microphone of the occluded-ear simulator as an electro-static speaker, the variability in estimating the emitted pressure from the ear is determined. The various measurement methods differ widely in their robustness to variations in the three principal factors influencing the accuracy and variability of ear-canal reflectance.

In-ear and on-body measurements of impulse-noise exposure.

Accurate quantification of noise exposure in military environments is challenging due to movement of listeners and noise sources, spectral and temporal noise characteristics, and varied use of hearing protection. This study evaluates a wearable recording device designed to measure on-body and in-ear noise exposure, specifically in an environment with significant impulse noise resulting from firearms. A commercial audio recorder was augmented to obtain simultaneous measurements inside the ear canal behind an integrated hearing protector, and near the outer ear. Validation measurements, conducted with an acoustic test fixture and shock tube, indicated high impulse peak insertion loss with a proper fit of the integrated hearing protector. The recording devices were worn by five subjects during a live-fire data collection at Marine Corps Base Quantico where Marines fired semi-automatic rifles. The field test demonstrated the successful measurement of high-level impulse waveforms with the on-body and in-ear recording system. Dual channels allowed for instantaneous fit estimates for the hearing protection component, and the device worked as intended in terms of hearing protection and noise dosimetry. Accurate measurements of noise exposure and hearing protector fit should improve the ability to model and assess the risks of noise-induced hearing loss.

Quantifying undesired parallel components in Thévenin-equivalent acoustic source parameters.

The calibration of an ear probe to determine its Thévenin-equivalent acoustic source parameters facilitates the measurement of ear-canal impedance and reflectance. Existing calibration error metrics, used to evaluate the quality of a calibration, are unable to reveal undesired parallel components in the source parameters. Such parallel components can result from, e.g., a leak in the ear tip or improperly accounting for evanescent modes, and introduce errors into subsequent measurements of impedance and reflectance. This paper proposes a set of additional error metrics that are capable of detecting such parallel components by examining the causality of the source admittance in the frequency domain and estimating the source pressure in the time domain. The proposed and existing error metrics are applied to four different calibrations using two existing calibration methods, representing typical use cases and introducing deliberate parallel components. The results demonstrate the capability of the proposed error metrics in identifying various undesired components in the source parameters that might otherwise go undetected.

An anti-barotrauma system for preventing barotrauma during hyperbaric oxygen therapy.

In the present study, a tympanometry-based anti-barotrauma (ABT) device was designed using eardrum admittance measurements to develop an objective method of preventing barotrauma that occurs during hyperbaric oxygen (HBO2) therapy. The middle ear space requires active equalization, and barotrauma of these tissues during HBO2therapy constitutes the most common treatment-associated injury. Decongestant nasal sprays and nasal steroids are used, but their efficacy is questionable to prevent middle ear barotrauma (MEB) during HBO2 treatment. Accordingly, a tympanometry-based ABT device was designed using eardrum admittance measurements to develop an objective method for preventing MEB, which causes pain and injury, and represents one of the principal reasons for patients to stop treatment. This study was conducted to test a novel technology that can be used to measure transmembrane pressures, and provide chamber attendants with real-time feedback regarding the patient's equalization status prior to the onset of pain or injury. Eardrum admittance values were measured according to pressure changes inside a hyperbaric oxygen chamber while the system was fitted to the subject. When the pressure increased to above 200 daPa, eardrum admittance decreased to 16.255% of prepressurization levels. After pressure equalization was achieved, eardrum admittance recovered to 95.595% of prepressurization levels. A one-way repeated measures analysis of variance contrast test was performed on eardrum admittance before pressurization versus during pressurization, and before pressurization versus after pressure equalization. The analysis revealed significant differences at all points during pressurization (P⟨0.001), but no significant difference after pressure equalization was achieved. This ABT device can provide objective feedback reflecting eardrum condition to the patient and the chamber operator during HBO2 therapy.

Effect of Body Mass Index on Middle Ear Resonance Frequency.

OBJECTIVE: Multifrequency tympanometry (MFT) analyzes tympanograms obtained using different probe tones between 226 and 2000 Hz. An important parameter of MFT is resonance frequency (RF). Studies have recently demonstrated that the RF value can vary depending on many factors. To provide new data regarding MFT, middle ear RF values were investigated with regard to body mass index (BMI). MATERIALS AND METHODS: This study included 78 volunteers (i.e., 156 ears) aged 18-40 years who did not have hearing loss and whose otoscopic examinations were normal. Hearing thresholds were measured using pure tone audiometry, and RF values were recorded with immitansmetric measurements. The participants were divided into the following three groups according to their BMI: <18.5 kg/m2, Group 1; 18.5-24.9 kg/m2, Group 2; and >25 kg/m2, Group 3. The RF values were also analyzed. RESULTS: Although there was no significant difference between Groups 1 and 2 in terms of RF values, a significant difference was observed between Groups 1 and 3 and between Groups 2 and 3. CONCLUSION: In the light of these data, BMI values should be considered when middle ear RF values are assessed.

Pure-Tone Audiometry With Forward Pressure Level Calibration Leads to Clinically-Relevant Improvements in Test-Retest Reliability.

OBJECTIVES: Clinical pure-tone audiometry is conducted using stimuli delivered through supra-aural headphones or insert earphones. The stimuli are calibrated in an acoustic (average ear) coupler. Deviations in individual-ear acoustics from the coupler acoustics affect test validity, and variations in probe insertion and headphone placement affect both test validity and test-retest reliability. Using an insert earphone designed for otoacoustic emission testing, which contains a microphone and loudspeaker, an individualized in-the-ear calibration can be calculated from the ear-canal sound pressure measured at the microphone. However, the total sound pressure level (SPL) measured at the microphone may be affected by standing-wave nulls at higher frequencies, producing errors in stimulus level of up to 20 dB. An alternative is to calibrate using the forward pressure level (FPL) component, which is derived from the total SPL using a wideband acoustic immittance measurement, and represents the pressure wave incident on the eardrum. The objective of this study is to establish test-retest reliability for FPL calibration of pure-tone audiometry stimuli, compared with in-the-ear and coupler sound pressure calibrations. DESIGN: The authors compared standard audiometry using a modern clinical audiometer with TDH-39P supra-aural headphones calibrated in a coupler to a prototype audiometer with an ER10C earphone calibrated three ways: (1) in-the-ear using the total SPL at the microphone, (2) in-the-ear using the FPL at the microphone, and (3) in a coupler (all three are derived from the same measurement). The test procedure was similar to that commonly used in hearing-conservation programs, using pulsed-tone test frequencies at 0.5, 1, 2, 3, 4, 6, and 8 kHz, and an automated modified Hughson-Westlake audiometric procedure. Fifteen adult human participants with normal to mildly-impaired hearing were selected, and one ear from each was tested. Participants completed 10 audiograms on each system, with test-order randomly varied and with headphones and earphones refitted by the tester between tests. RESULTS: Fourteen of 15 ears had standing-wave nulls present between 4 and 8 kHz. The mean intrasubject SD at 6 and 8 kHz was lowest for the FPL calibration, and was comparable with the low-frequency reliability across calibration methods. This decrease in variability translates to statistically-derived significant threshold shift criteria indicating that 15 dB shifts in hearing can be reliably detected at 6 and 8 kHz using FPL-calibrated ER10C earphones, compared with 20 to 25 dB shifts using standard TDH-39P headphones with a coupler calibration. CONCLUSIONS: These results indicate that reliability is better with insert earphones, especially with in-the-ear FPL calibration, compared with a standard clinical audiometer with supra-aural headphones. However, in-the-ear SPL calibration should not be used due to its sensitivity to standing waves. The improvement in reliability is clinically meaningful, potentially allowing hearing-conservation programs to more confidently determine significant threshold shifts at 6 kHz-a key frequency for the early detection of noise-induced hearing loss.

The effect of SpeechEasy ® on attitudes, emotions and coping behaviors. Outcomes of short time usage / Efecto de SpeechEasy ® en actitud, emociones y estrategias de afrontamiento. Resultado de uso a corto plazo

This study investigated the effect of SpeechEasy® on attitudes, emotions and coping behaviors after a short period of usage. Nine individuals who stutter were fitted with the SpeechEasy® and used the device for at least 4 h/day during a period of less than 2 months. Before and after this period spontaneous speech samples were collected and attitudes, emotions and coping behaviors were assessed by means of the Behavior Assessment Battery () and the adult form of the Communication Attitude Test (). Results indicate that after a short time using the SpeechEasy® some people who stutter may to some extent show an amelioration of the negative attitudes, emotions and coping behaviors that usually accompany the stuttering. However, self-reported changes in attitudes, emotions and coping behaviors do not necessarily reflect objective fluency scores and there seems to be considerable individual variation in reaction the SpeechEasy® (AU)

El presente estudio investiga el efecto del SpeechEasy® en la actitud, las emociones y las estrategias de afrontamiento después de un breve periodo de uso. Se colocó un SpeechEasy® a nueve individuos tartamudos, que lo utilizaron durante un mínimo de cuatro horas diarias a lo largo de un periodo inferior a dos meses. Antes y después de este periodo se tomaron muestras de habla y se evaluaron la actitud, las emociones y las estrategias de afrontamiento por medio del Behavior Assessment Battery () y del formulario para adultos de Communication Attitude Test (). Los resultados indican que poco tiempo después de usar el SpeechEasy® algunas personas que tartamudean podrían mostrar una cierta mejora de las actitudes, emociones y estrategias de afrontamiento negativas que suelen acompañar el tartamudeo. No obstante, la autoevaluación de los cambios en estos aspectos no necesariamente reflejan una puntación de fluidez objetiva y parece existir una variación individual considerable respecto al SpeechEasy® (AU)

Quantitative analysis of inner-ear barotrauma using a Eustachian tube function analyzer.

OBJECTIVES: We investigated the relationship between Eustachian tube function and incidence of inner-ear barotrauma (IEBt) in recreational divers. METHODS: Sixteen patients who experienced a scuba diving injury affecting the inner ear and 20 healthy volunteers who had not experienced a diving injury participated. Healthy volunteers and divers with IEBt received impedance tests regularly to assess Eustachian tube function. Test results from these groups were compared. RESULTS: There were no significant differences between test results of IEBt divers and healthy volunteers. However, seven IEBt divers were judged to have irregular compliance curves on impedance testing. Seven of the 16 IEBt divers experienced vertigo. In nearly all of the IEBt divers with vertigo, hearing loss type was manifested as high-tone deafness, and IEBt symptoms appeared during diving. These symptoms were more serious especially when the diving depth was deeper. CONCLUSIONS: To prevent IEBt in scuba divers, we recommend a thorough Eustachian tube function evaluation. Any dysfunction should be treated before engaging in scuba diving. We need to assess more divers who have experienced IEBt and thoroughly examine how their injury happened.

Uso de la timpanometría en Atención Primaria / Use of tympanometry in Primary Care

Dada la elevada prevalencia de la otitis media en la población infantil y las dificultades que a esta edad presenta la otoscopia para establecer el diagnóstico, la timpanometría aporta información cuantitativa valiosa respecto a la presencia de líquido en el oído medio. Es una exploración habitual en todos los Servicios de Otorrinolaringología (ORL) y pensamos que podría ser de gran utilidad en Atención Primaria. En este trabajo pretendemos aportar el conocimiento teórico necesario para comprender e interpretar las curvas que obtendremos con un timpanómetro portátil, discutiendo las características y beneficios de esta prueba. Con la intención de mejorar la capacidad de seguimiento de la otitis media serosa (OMS) en Atención Primaria, constituimos un equipo de pediatras y ORL de la misma área de salud para ir introduciendo y adaptando un conjunto de procedimientos, entre los que se encuentra la timpanometría. El aparato elegido ha sido el timpanómetro MicroTymp®3 de Welch-Allyn y la exploración es realizada por una enfermera experimentada en esta prueba. Al pediatra le corresponde la interpretación de los hallazgos timpanométricos, que, junto a la historia clínica y la otoscopia neumática, le facilitarán el diagnóstico. Se describen los fundamentos de la timpanometría y la manera de realizar y analizar los timpanogramas. Discutimos las ventajas y limitaciones de esta exploración en el contexto de la otitis media serosa infantil en Atención Primaria. En niños mayores de seis meses, la timpanometría con MicroTymp®3 es una herramienta práctica y eficaz en el diagnóstico de la OMS en Atención Primaria (AU)

Due to the high prevalence of otitis media in children and to the difficulties of otoscopy to establish the diagnosis at this age, tympanometry brings valuable quantitative information about the presence of fluid in the middle ear. It is a usual scan on all services of ENT and we think that it could be very useful in primary care. In this paper we aim to provide the theoretical knowledge necessary to understand and interpret the curves you get with a portable instrument, discussing the features and benefits of this test. We are a team of pediatricians and ENT of the same Area of health who pretend to improve the follow up of otitis media with effusion (OME) in primary care; we are introducing and adapting a set of procedures, which include tympanometry. The selected device has been MicroTymp®3 Welch-Allyn and the scan is performed by a nurse experienced in this test. The pediatrician interpretate the tympanometric findings, that along with the clinical history and pneumatic otoscopy, will facilitate the diagnosis. We describe the fundamentals of tympanometry and how to perform and interpret the tympanograms. We discuss the advantages and limitations of this exploration in the context of OME in primary care. The Welch Allyn MicroTymp®3 is a practical and effective tool in the diagnosis of OME in children older than 6 months in primary care (AU)

Métodos de evaluación de la composición corporal: una revisión actualizada de descripción, aplicación, ventajas y desventajas / Methods of assessment of body composition: an updated review of description, application, advantages and disadvantages

El estudio de la composición corporal es un tema de interés creciente que puede ser utilizado tanto para la investigación como para fines clínicos. Para los profesionales de las ciencias de la salud es importante conocer las características de los diferentes métodos de evaluación y análisis de la composición corporal, ya que cambios en esta guardan relación directa con la salud y el riesgo de enfermedades. Actualmente, los métodos de análisis de la composición corporal son divididos en tres grupos, donde están el directo, los indirectos y los doblemente indirectos. El método directo es la disección de cadáveres. Entre los indirectos encontramos la tomografía axial computarizada, la resonancia magnética nuclear (RMN), la absorciometría dual de rayos X y la plestimografía; y en lo referente a los métodos doblemente indirectos destacan la antropometría y la impedancia bioelectrica. Asi, este trabajo tiene como objetivo revisar los métodos mas utilizados para el análisis de la composición corporal, describiéndoles, analizando sus aplicaciones, ventajas y desventajas. Se llevo a cabo una búsqueda de artículos en las bases de datos PubMed, Web of Science, Scopus, SportDiscus y Google Academico. Las palabras usadas fueron, body composition, body mass, body fat, muscle mass, fat mass, measurement, assessment y evaluation, aisladas o combinadas, y sus respectivos sinónimos en castellano y portugués. Fueron encontrados 221 artículos, de los cuales fueron seleccionados 59 para esta revisión. Se concluye que los diferentes métodos para evaluar la composición corporal presentan ventajas y desventajas, que deben ser analizados cuando se elige el método a ser empleado, para intentar minimizar sus desventajas y potencializar sus ventajas (AU)

The study of body composition is a topic of growing interest that can be used both for research and for clinical purposes. For professionals of health sciences is important to know the characteristics of the different methods of evaluation and analysis of body composition because, it changes are directly related to health and disease risk. Currently, methods of analysis of body composition are divided into three groups, which are direct, indirect and double indirect. The direct method is the dissection of cadavers. Indirect find computed tomography, magnetic resonance imaging, dual X-ray absorptiometry and plethysmography and in terms of the doubly indirect methods include anthropometry and bioelectrical impedance. Thus, this paper is aimed to review the most used for analysis of body composition by describing, analyzing their applications, advantages and disadvantages methods. Was conducted a search of article in databases PubMed, Web of Science, Scopus, SportDiscus and Google Scholar. The words used were, body composition, body mass, body fat, muscle mass, fat mass, measurement, assessment and evaluation, isolated or combined and their alternatives in Castilian and Portuguese. Were selected articles that were in English, Castilian and portuguese. They were found 221 articles, of which 59 were selected for this review. It is concluded that the different methods for assessing body composition have advantages and disadvantages, which should be analyzed when choosing the method to be used to try to minimize the disadvantages and empower its advantages (AU)

Acoustic reflex on newborns: the influence of the 226 and 1,000 Hz probes.

PURPOSE: To analyze the occurrence of acoustic reflex and its threshold on newborns using the 226 and 1,000 Hz probes. METHODS: Thirty-six newborns with "PASS" results in newborn hearing screening and tympanogram with one or two peaks for both probe tones were included. Group I comprised 20 full-term newborns without risk indicator for hearing loss, and Group II comprised 16 newborns with at least one risk indicator. The study about ipsilateral acoustic reflex thresholds was conducted in 500, 1,000, 2,000, and 4,000 Hz. RESULTS: The groups presented the acoustic reflex thresholds between 50 and 100 dB for both probe tones. In the comparison between the probes, there were differences in all frequencies evaluated in Group I, with the lowest threshold mean for the 1,000 Hz probe. In Group II, differences were detected at 2,000 Hz. The mean acoustic reflex thresholds were similar in both groups for the 226 Hz probe. There was a difference for the 1,000 Hz probe in all tested frequencies. The percentage of response was higher in both groups for the 1,000 Hz probe. The kappa test showed extremely poor agreement in the comparison of results between both probes. CONCLUSION: The occurrence of acoustic reflex was higher in newborns and its thresholds were lower with the 1,000 Hz probe both for healthy newborns and for newborns at risk.

Acoustic reflex on newborns: the influence of the 226 and 1,000 Hz probes / A influência da sonda de 226 e 1.000 Hz no registro do reflexo acústico em neonatos

PURPOSE: To analyze the occurrence of acoustic reflex and its threshold on newborns using the 226 and 1,000 Hz probes. METHODS: Thirty-six newborns with "PASS" results in newborn hearing screening and tympanogram with one or two peaks for both probe tones were included. Group I comprised 20 full-term newborns without risk indicator for hearing loss, and Group II comprised 16 newborns with at least one risk indicator. The study about ipsilateral acoustic reflex thresholds was conducted in 500, 1,000, 2,000, and 4,000 Hz. RESULTS: The groups presented the acoustic reflex thresholds between 50 and 100 dB for both probe tones. In the comparison between the probes, there were differences in all frequencies evaluated in Group I, with the lowest threshold mean for the 1,000 Hz probe. In Group II, differences were detected at 2,000 Hz. The mean acoustic reflex thresholds were similar in both groups for the 226 Hz probe. There was a difference for the 1,000 Hz probe in all tested frequencies. The percentage of response was higher in both groups for the 1,000 Hz probe. The kappa test showed extremely poor agreement in the comparison of results between both probes. CONCLUSION: The occurrence of acoustic reflex was higher in newborns and its thresholds were lower with the 1,000 Hz probe both for healthy newborns and for newborns at risk. .

OBJETIVO: Verificar a ocorrência e o limiar do reflexo acústico em neonatos utilizando a sonda de 226 e 1.000 Hz. MÉTODOS: Trinta e seis neonatos com resultado "PASS" na triagem auditiva neonatal e timpanogramas com um ou dois picos para os dois tons de sonda. O Grupo I foi composto por 20 neonatos a termo sem indicador de risco para deficiência auditiva e o Grupo II, por 16 neonatos com pelo menos um indicador de risco. A pesquisa dos limiares do reflexo acústico ipsilateral foi realizada em 500, 1.000, 2.000 e 4.000 Hz. RESULTADOS: Os grupos apresentaram limiar do reflexo acústico entre 50 e 100 dB para ambos os tons de sonda. Na comparação entre as sondas, houve diferença em todas as frequências avaliadas no Grupo I, com a média de limiares menor com a sonda de 1.000 Hz. No Grupo II, foi detectada diferença em 2.000 Hz. Com a sonda de 226 Hz, os limiares médios do reflexo acústico foram semelhantes nos dois grupos. Com a sonda de 1.000 Hz, houve diferença em todas as frequências avaliadas. A porcentagem de presença de resposta foi maior para ambos os grupos para a sonda de 1.000 Hz. O teste kappa revelou concordância extremamente pobre na comparação dos resultados entre as duas sondas. CONCLUSÃO: A ocorrência de reflexo acústico em neonatos foi maior e os limiares menores com a utilização da sonda de 1.000 Hz, tanto para neonatos saudáveis como para os neonatos de risco. .

Handheld tympanometer measurements in conscious dogs for the evaluation of the middle ear and auditory tube.

BACKGROUND: Otitis externa is frequently accompanied by otitis media, yet it can be difficult to evaluate the tympanum, middle ear and auditory tube without the use of advanced radiographic imaging. HYPOTHESIS/OBJECTIVES: The objective was to develop techniques for tympanometry testing in conscious dogs and to present normative data for clinical use of this equipment to enable assessment of the tympanum, middle ear and auditory tube. ANIMALS: Sixteen hounds (14 female) from a school teaching colony. METHODS: Dogs were gently restrained in a standing position. After cleaning of the ear canal, a tympanometer probe tip extension was placed in the vertical canal and automated testing performed using a handheld device. Both ears were tested in all dogs. RESULTS: Acceptable recordings were obtained from both ears of 13 dogs, from one ear in each of two dogs and from neither ear of one dog, resulting in data from 28 of 32 (88%) ears. Otoscopic examination confirmed the absence of inflammation or any other obvious explanation for the noncompliant dogs. No significant differences were seen between ears for any measure. Normative data are reported for peak compliance, peak compliance pressure, gradient and ear canal volume. CONCLUSIONS AND CLINICAL IMPORTANCE: Tympanograms can be recorded in conscious dogs to assist in the evaluation of the middle ear structures.

Cribado auditivo mediante potenciales evocados auditivos de estado estable obtenidos por estimulación simultánea de la vía aérea y la ósea / Hearing screening using auditory steady state responses obtained by simultaneous air- and bone-conduction stimuli

Introducción y objetivos: Minimizar los falsos positivos constituye un objetivo de los programas de cribado auditivo universal. Una manera de lograrlo sería diferenciar entre los trastornos neurosensoriales (verdaderos positivos) y los conductivos transitorios (falsos positivos) mediante un método que permita estudiar la respuesta del sistema auditivo ante la estimulación tanto por vía aérea como por vía ósea. El objetivo de este trabajo es evaluar la eficiencia diagnóstica de una prueba automatizada de cribado basada en el registro de potenciales evocados auditivos de estado estable obtenidos por estimulación simultánea de vía aérea y vía ósea. Métodos: Se estudiaron 80 bebés menores de 2 meses de edad. A todos se les realizó la prueba de cribado, siendo posteriormente citados para el estudio confirmatorio, cuyo resultado se consideró como criterio de verdad del estado audiológico del bebé. Resultados: Con esta prueba se obtuvo una eficiencia diagnóstica equivalente (un 100% de sensibilidad y un 97,7% de especificidad) a la reportada para otras pruebas utilizadas en el cribado (emisiones otoacústicas y potenciales evocados de tronco cerebral), con la ventaja adicional de que la introducción de la vía ósea en el cribado permitió reducir la cifra de falsos positivos del 13,3 al 2,2%. La duración de la prueba fue de 5,3 (± 1,9) min, siendo suficiente en el 34% de los casos una sola repetición para llegar al resultado. Conclusiones: Esta prueba automatizada de cribado basada en el registro de potenciales evocados auditivos de estado estable permitió discriminar entre los trastornos conductivos transitorios y los neurosensoriales, reduciendo así los falsos positivos y elevando la eficiencia diagnóstica de esta metodología (AU)

Introduction and objectives: Minimising false positives rates is an important goal of universal newborn hearing screening programmes. An adequate way for reaching that goal could be differentiating between transient conductive hearing losses (false positives) and permanent sensorineural hearing impairments (true positives) by means of a methodology that studies electrophysiological responses obtained using both air- and bone-conduction stimuli. Our objective was to evaluate the efficiency of an automated hearing screening test based on auditory steady state responses obtained using simultaneous air- and bone-conduction stimuli. Methods: A sample of 80 high risk babies lees than 2 months of born were screened using the automatic screening test. A confirmatory clinical and electrophysiological evaluation was used as the gold standard. Results: The estimated diagnostic efficiency of this screening test was equivalent (100% sensitivity and 97.7% specificity) to the efficiency reported for otoacoustic emissions and automated auditory brainstem responses. The introduction of bone conduction in the screening reduced the false positive rate from 13.3% to 2.2%. The test duration was 5.3 (± 1.9) min. In 34% of babies only one repetition of the test was needed to raising the result. Conclusions: The screening test performed quite well in this initial clinical trial, differentiating transient conductive hearing losses from permanent neurosensory impairments and improving the diagnostic efficiency of auditory steady state responses (AU)

Usefulness of 1000-Hz probe tone in tympanometry according to age in Korean infants.

OBJECTIVE: Numerous studies have shown the superiority of a 1000-Hz frequency probe tone for evaluating the middle ear status of infants. However, most of these studies examined Caucasian populations. This study validated the 1000-Hz probe tone and evaluated the age at which it should be used in Korean infants. METHODS: Data from 83 infants (43 males, 40 females; mean age 9.2±6.2 (range 1-30) months, 165 ears) were analyzed. Tympanograms were classified according to Baldwin's modification of the method of Marchant et al. and correlated with results based on combined diagnostic tests, including an endoscopic examination of the tympanic membrane, myringotomy findings, and the air and bone conduction auditory brainstem response (ABR) thresholds. Data were analyzed in five age groups, each covering a 3-month range. The traces were measured for both 226- and 1000-Hz probe tones. The sensitivity and specificity for the different age groups were also determined. RESULTS: For the 226-Hz probe tone, the tympanograms showed normal traces for most ears with otitis media effusions in infants younger than 12 months. By contrast, the tympanograms using the 1000-Hz probe tone showed abnormal traces in most of the infants with otitis media effusions in all age groups. In infants with no otitis media effusion, the tympanograms using both 226- and 1000-Hz probe tones were interpreted as normal in most cases in all age groups. In infants younger than 12 months, the sensitivity of the 226-Hz probe tone was very low (0-6.6%), whereas that of the 1000-Hz probe tone was very high (90-100%). In infants older than 13 months, however, the sensitivities of the 226- and 1000-Hz probe tones were 76.2% and 85.7%, respectively. Regarding specificity, the difference between the two probe tones was not significant for any age group. CONCLUSIONS: This study confirmed the superiority of the 1000-Hz probe tone for evaluating the middle ear in infants. We recommend using a 1000-Hz probe tone at least up to the age of 12 months for Korean infants.

Electro-acoustic performance of the new bone vibrator Radioear B81: a comparison with the conventional Radioear B71.

OBJECTIVE: The objective is to evaluate the electro-acoustic performance of a new audiometric bone vibrator, the B81 from Radioear Corporation, USA. Comparison will be made with the widely used B71 which has well-known limitations at low frequencies. DESIGN: The B81 is based on the balanced electromagnetic separation transducer (BEST) principle where static forces are counterbalanced so that nonlinear distortion forces are reduced and maximum hearing levels can be increased. STUDY SAMPLE: Maximum hearing level, total harmonic distortion (THD), frequency response, and electrical impedance were measured for six devices of each bone vibrator type on an artificial mastoid. RESULTS: It was found that B81 reaches 10.7-22.0 dB higher maximum (@ THD = 6% or Vin = 6 VRMS) hearing levels than B71 for frequencies below 1500 Hz, and had significantly lower THD up to 1000 Hz. There was no statistically significant difference between their frequency response, except a deviation at the mid frequencies (α = 0.01) where B81 was more efficient and the electrical impedances were practically the same. CONCLUSIONS: In general, B81 had an improved electro-acoustic performance compared to B71 and is compatible with same audiometers. In particular, B81 allows for sensorineural hearing loss to be measured at considerably higher hearing levels than with B71 below 1500 Hz.