Vibration of middle ear with shape memory prosthesis - Experimental and numerical study

NASA Astrophysics Data System (ADS)

Rafal, Rusinek; Szymanski, Marcin; Lajmert, Pawel

2018-01-01

The paper presents experimental investigations of ossicular chain vibrations using a Laser Doppler Vibrometer (LDV) for the intact middle ear and a reconstructed one by means of the new designed shape memory prosthesis. Vibrations of the round window are measured with the Laser Doppler vibrometer and studied classically by the transfer function analysis. Moreover, the recurrence plot technique and the Hilbert vibration decomposition method are used to extend the classical analysis. The new methods show additional vibrations components and provide more information about middle ear behaviour.

Simulations and Measurements of Human Middle Ear Vibrations Using Multi-Body Systems and Laser-Doppler Vibrometry with the Floating Mass Transducer.

PubMed

Böhnke, Frank; Bretan, Theodor; Lehner, Stefan; Strenger, Tobias

2013-10-22

The transfer characteristic of the human middle ear with an applied middle ear implant (floating mass transducer) is examined computationally with a Multi-body System approach and compared with experimental results. For this purpose, the geometry of the middle ear was reconstructed from μ-computer tomography slice data and prepared for a Multi-body System simulation. The transfer function of the floating mass transducer, which is the ratio of the input voltage and the generated force, is derived based on a physical context. The numerical results obtained with the Multi-body System approach are compared with experimental results by Laser Doppler measurements of the stapes footplate velocities of five different specimens. Although slightly differing anatomical structures were used for the calculation and the measurement, a high correspondence with respect to the course of stapes footplate displacement along the frequency was found. Notably, a notch at frequencies just below 1 kHz occurred. Additionally, phase courses of stapes footplate displacements were determined computationally if possible and compared with experimental results. The examinations were undertaken to quantify stapes footplate displacements in the clinical practice of middle ear implants and, also, to develop fitting strategies on a physical basis for hearing impaired patients aided with middle ear implants.

A prediction of the minke whale (Balaenoptera acutorostrata) middle-ear transfer functiona)

PubMed Central

Tubelli, Andrew A.; Zosuls, Aleks; Ketten, Darlene R.; Yamato, Maya; Mountain, David C.

2012-01-01

The lack of baleen whale (Cetacea Mysticeti) audiograms impedes the assessment of the impacts of anthropogenic noise on these animals. Estimates of audiograms, which are difficult to obtain behaviorally or electrophysiologically for baleen whales, can be made by simulating the audiogram as a series of components representing the outer, middle, and inner ear (Rosowski, 1991; Ruggero and Temchin, 2002). The middle-ear portion of the system can be represented by the middle-ear transfer function (METF), a measure of the transmission of acoustic energy from the external ear to the cochlea. An anatomically accurate finite element model of the minke whale (Balaenoptera acutorostrata) middle ear was developed to predict the METF for a mysticete species. The elastic moduli of the auditory ossicles were measured by using nanoindentation. Other mechanical properties were estimated from experimental stiffness measurements or from published values. The METF predicted a best frequency range between approximately 30 Hz and 7.5 kHz or between 100 Hz and 25 kHz depending on stimulation location. Parametric analysis found that the most sensitive parameters are the elastic moduli of the glove finger and joints and the Rayleigh damping stiffness coefficient β. The predicted hearing range matches well with the vocalization range. PMID:23145610

Effects of middle ear quasi-static stiffness on sound transmission quantified by a novel 3-axis optical force sensor.

PubMed

Dobrev, Ivo; Sim, Jae Hoon; Aqtashi, Baktash; Huber, Alexander M; Linder, Thomas; Röösli, Christof

2018-01-01

Intra-operative quantification of the ossicle mobility could provide valuable feedback for the current status of the patient's conductive hearing. However, current methods for evaluation of middle ear mobility are mostly limited to the surgeon's subjective impression through manual palpation of the ossicles. This study investigates how middle ear transfer function is affected by stapes quasi-static stiffness of the ossicular chain. The stiffness of the middle ear is induced by a) using a novel fiber-optic 3-axis force sensor to quantify the quasi-static stiffness of the middle ear, and b) by artificial reduction of stapes mobility due to drying of the middle ear. Middle ear transfer function, defined as the ratio of the stapes footplate velocity versus the ear canal sound pressure, was measured with a single point LDV in two conditions. First, a controlled palpation force was applied at the stapes head in two in-plane (superior-inferior or posterior-anterior) directions, and at the incus lenticular process near the incudostapedial joint in the piston (lateral-medial) direction with a novel 3-axis PalpEar force sensor (Sensoptic, Losone, Switzerland), while the corresponding quasi-static displacement of the contact point was measured via a 3-axis micrometer stage. The palpation force was applied sequentially, step-wise in the range of 0.1-20 gF (1-200 mN). Second, measurements were repeated with various stages of stapes fixation, simulated by pre-load on the stapes head or drying of the temporal bone, and with severe ossicle immobilization, simulated by gluing of the stapes footplate. Simulated stapes fixation (forced drying of 5-15 min) severely decreases (20-30 dB) the low frequency (<1 kHz) response of the middle ear, while increasing (5-10 dB) the high frequency (>4 kHz) response. Stapes immobilization (gluing of the footplate) severely reduces (20-40 dB) the low and mid frequency response (<4 kHz) but has lesser effect (<10 dB) at higher frequencies. Even moderate levels of palpation force (<3gF, <30 mN), regardless of direction, have negative effect (10-20 dB) on the low frequency (<2 kHz) response, but with less significant (5-10 dB) effect at higher frequencies. Force-displacement measurements around the incudostapedial joint showed quasi-static stiffness in the range of 200-500 N/m for normal middle ears, and 1000-2500 N/m (5-8-fold increase) after artificially (through forced drying) reducing the middle ear transfer function with 10-25 dB at 1 kHz. Effects of the palpation force level and direction, as well as stapes fixation and immobilization have been analyzed based on the measurement of the stapes footplate motion, and controlled application of 3D force and displacement. Copyright © 2017 Elsevier B.V. All rights reserved.

Intracochlear pressure measurements during acoustic shock wave exposure.

PubMed

Greene, Nathaniel T; Alhussaini, Mohamed A; Easter, James R; Argo, Theodore F; Walilko, Tim; Tollin, Daniel J

2018-05-19

Injuries to the peripheral auditory system are among the most common results of high intensity impulsive acoustic exposure. Prior studies of high intensity sound transmission by the ossicular chain have relied upon measurements in animal models, measurements at more moderate sound levels (i.e. < 130 dB SPL), and/or measured responses to steady-state noise. Here, we directly measure intracochlear pressure in human cadaveric temporal bones, with fiber optic pressure sensors placed in scala vestibuli (SV) and tympani (ST), during exposure to shock waves with peak positive pressures between ∼7 and 83 kPa. Eight full-cephalic human cadaver heads were exposed, face-on, to acoustic shock waves in a 45 cm diameter shock tube. Specimens were exposed to impulses with nominal peak overpressures of 7, 28, 55, & 83 kPa (171, 183, 189, & 192 dB pSPL), measured in the free field adjacent to the forehead. Specimens were prepared bilaterally by mastoidectomy and extended facial recess to expose the ossicular chain. Ear canal (EAC), middle ear, and intracochlear sound pressure levels were measured with fiber-optic pressure sensors. Surface-mounted sensors measured SPL and skull strain near the opening of each EAC and at the forehead. Measurements on the forehead showed incident peak pressures approximately twice that measured by adjacent free-field and EAC entrance sensors, as expected based on the sensor orientation (normal vs tangential to the shock wave propagation). At 7 kPa, EAC pressure showed gain, calculated from the frequency spectra, consistent with the ear canal resonance, and gain in the intracochlear pressures (normalized to the EAC pressure) were consistent with (though somewhat lower than) previously reported middle ear transfer functions. Responses to higher intensity impulses tended to show lower intracochlear gain relative to EAC, suggesting sound transmission efficiency along the ossicular chain is reduced at high intensities. Tympanic membrane (TM) rupture was observed following nearly every exposure 55 kPa or higher. Intracochlear pressures reveal lower middle-ear transfer function magnitudes (i.e. reduced gain relative to the ear canal) for high sound pressure levels, thus revealing lower than expected cochlear exposure based on extrapolation from cochlear pressures measured at more moderate sound levels. These results are consistent with lowered transmissivity of the ossicular chain at high intensities, and are consistent with our prior report measuring middle ear transfer functions in human cadaveric temporal bones with high intensity tone pips. Copyright © 2018 Elsevier B.V. All rights reserved.

How is sound conducted to the cochlea in toothed whales?

NASA Astrophysics Data System (ADS)

Zosuls, Aleks; Mountain, David C.; Ketten, Darlene R.

2015-12-01

Toothed whales (Odontocetes) typically have small occluded ear canals and sea water has a characteristic impedance that is much more similar to the impedance of soft tissues of the head than is the case for the air-tissue interface in terrestrial mammals. This makes it plausible that significant acoustic energy is being transmitted to their middle ear by tissue conduction. In addition, some authors have proposed that sound reaches the cochlea via bone conduction rather than via the tympanic membrane. To address these issues, we have developed a method to measure stapes velocity in response to vibrational stimulation at arbitrary locations on heads and ears harvested from stranded animals. Stapes velocity was measured with a Laser Doppler Velocimeter at the footplate with the cochlea drained. In all species tested, the transfer function of stapes velocity referenced to actuator velocity showed a high-pass characteristic. The corner frequency varied with species and experiment between 4 kHz and 60 kHz. This is similar to what is seen in odontocete audiograms but the cutoff slope is typically steeper than in the audiograms. There was no indication of high frequency cutoff within our measurement range. Disrupting the ossicles and fat bodies affected the transfer functions.

Head related transfer functions measurement and processing for the purpose of creating a spatial sound environment

NASA Astrophysics Data System (ADS)

Pec, Michał; Bujacz, Michał; Strumiłło, Paweł

2008-01-01

The use of Head Related Transfer Functions (HRTFs) in audio processing is a popular method of obtaining spatialized sound. HRTFs describe disturbances caused in the sound wave by the human body, especially by head and the ear pinnae. Since these shapes are unique, HRTFs differ greatly from person to person. For this reason measurement of personalized HRTFs is justified. Measured HRTFs also need further processing to be utilized in a system producing spatialized sound. This paper describes a system designed for efficient collecting of Head Related Transfer Functions as well as the measurement, interpolation and verification procedures.

Audiometric Predictions Using SFOAE and Middle-Ear Measurements

PubMed Central

Ellison, John C.; Keefe, Douglas H.

2006-01-01

Objective The goals of the study are to determine how well stimulus-frequency otoacoustic emissions (SFOAEs) identify hearing loss, classify hearing loss as mild or moderate-severe, and correlate with pure-tone thresholds in a population of adults with normal middle-ear function. Other goals are to determine if middle-ear function as assessed by wideband acoustic transfer function (ATF) measurements in the ear canal account for the variability in normal thresholds, and if the inclusion of ATFs improves the ability of SFOAEs to identify hearing loss and predict pure-tone thresholds. Design The total suppressed SFOAE signal and its corresponding noise were recorded in 85 ears (22 normal ears and 63 ears with sensorineural hearing loss) at octave frequencies from 0.5 – 8 kHz using a nonlinear residual method. SFOAEs were recorded a second time in three impaired ears to assess repeatability. Ambient-pressure ATFs were obtained in all but one of these 85 ears, and were also obtained from an additional 31 normal-hearing subjects in whom SFOAE data were not obtained. Pure-tone air-and bone-conduction thresholds and 226-Hz tympanograms were obtained on all subjects. Normal tympanometry and the absence of air-bone gaps were used to screen subjects for normal middle-ear function. Clinical decision theory was used to assess the performance of SFOAE and ATF predictors in classifying ears as normal or impaired, and linear regression analysis was used to test the ability of SFOAE and ATF variables to predict the air-conduction audiogram. Results The ability of SFOAEs to classify ears as normal or hearing impaired was significant at all test frequencies. The ability of SFOAEs to classify impaired ears as either mild or moderate-severe was significant at test frequencies from 0.5 to 4 kHz. SFOAEs were present in cases of severe hearing loss. SFOAEs were also significantly correlated with air-conduction thresholds from 0.5 to 8 kHz. The best performance occurred using the SFOAE signal-to-noise ratio (S/N) as the predictor, and the overall best performance was at 2 kHz. The SFOAE S/N measures were repeatable to within 3.5 dB in impaired ears. The ATF measures explained up to 25% of the variance in the normal audiogram; however, ATF measures did not improve SFOAEs predictors of hearing loss except at 4 kHz. Conclusions In common with other OAE types, SFOAEs are capable of identifying the presence of hearing loss. In particular, SFOAEs performed better than distortion-product and click-evoked OAEs in predicting auditory status at 0.5 kHz; SFOAE performance was similar to that of other OAE types at higher frequencies except for a slight performance reduction at 4 kHz. Because SFOAEs were detected in ears with mild to severe cases of hearing loss they may also provide an estimate of the classification of hearing loss. Although SFOAEs were significantly correlated with hearing threshold, they do not appear to have clinical utility in predicting a specific behavioral threshold. Information on middle-ear status as assessed by ATF measures offered minimal improvement in SFOAE predictions of auditory status in a population of normal and impaired ears with normal middle-ear function. However, ATF variables did explain a significant fraction of the variability in the audiograms of normal ears, suggesting that audiometric thresholds in normal ears are partially constrained by middle-ear function as assessed by ATF tests. PMID:16230898

Fixation and detachment of superior and anterior malleolar ligaments in human middle ear: Experiment and modeling

PubMed Central

Dai, Chenkai; Cheng, Tao; Wood, Mark W.; Gan, Rong Z.

2007-01-01

The aim of this study is to investigate the function of the superior malleolar ligament (SML) and the anterior malleolar ligament (AML) in human middle ear for sound transmission through simulations of fixation and detachment of these ligaments in human temporal bones and a finite element (FE) ear model. Two laser vibrometers were used to measure the vibrations of the tympanic membrane (TM) and stapes footplate. A 3-D FE ear model was used to predict the transfer function of the middle ear with ligament fixation and detachment. The results demonstrate that fixations and detachments of the SML and AML had different effects on TM and stapes footplate movements. Fixation of the SML resulted in a reduction of displacement of the TM (umbo) and the footplate at low frequencies (f < 1000 Hz), but also caused a shift of displacement peak to higher frequencies. Fixation of both SML and AML caused a reduction of 15 dB at umbo or stapes at low frequencies. Detachment of the SML had almost no effect on TM and footplate mobility, but AML detachment had a minor effect on TM and footplate movement. The FE model was able to predict the effects of SML and AML fixation and detachment. PMID:17517484

Finite element modelling of human auditory periphery including a feed-forward amplification of the cochlea.

PubMed

Wang, Xuelin; Wang, Liling; Zhou, Jianjun; Hu, Yujin

2014-08-01

A three-dimensional finite element model is developed for the simulation of the sound transmission through the human auditory periphery consisting of the external ear canal, middle ear and cochlea. The cochlea is modelled as a straight duct divided into two fluid-filled scalae by the basilar membrane (BM) having an orthotropic material property with dimensional variation along its length. In particular, an active feed-forward mechanism is added into the passive cochlear model to represent the activity of the outer hair cells (OHCs). An iterative procedure is proposed for calculating the nonlinear response resulting from the active cochlea in the frequency domain. Results on the middle-ear transfer function, BM steady-state frequency response and intracochlear pressure are derived. A good match of the model predictions with experimental data from the literatures demonstrates the validity of the ear model for simulating sound pressure gain of middle ear, frequency to place map, cochlear sensitivity and compressive output for large intensity input. The current model featuring an active cochlea is able to correlate directly the sound stimulus in the ear canal with the vibration of BM and provides a tool to explore the mechanisms by which sound pressure in the ear canal is converted to a stimulus for the OHCs.

A 3D-printed functioning anatomical human middle ear model.

PubMed

Kuru, Ismail; Maier, Hannes; Müller, Mathias; Lenarz, Thomas; Lueth, Tim C

2016-10-01

The middle ear is a sophisticated and complex structure with a variety of functions, yet a delicate organ prone to injuries due to various reasons. Both, understanding and reconstructing its functions has always been an important topic for researchers from medical and technical background. Currently, human temporal bones are generally used as model for tests, experiments and validation of the numerical results. However, fresh human preparations are not always easily accessible and their mechanical properties vary with time and between individuals. Therefore we have built an anatomically based and functional middle ear model to serve as a reproducible test environment. Our middle ear model was manufactured with the aid of 3D-printing technology. We have segmented the essential functional elements from micro computed tomography data (μCT) of a single temporal bone. The ossicles were 3D-printed by selective laser melting (SLM) and the soft tissues were casted with silicone rubber into 3D-printed molds. The ear canal, the tympanic cavity and the inner ear were artificially designed, but their design ensured the anatomically correct position of the tympanic membrane, ossicular ligaments and the oval window. For the determination of their auditory properties we have conducted two kinds of tests: measurement of the stapes footplate response to sound and tympanometry of the model. Our experiments regarding the sound transmission showed that the model has a similar behavior to a human middle ear. The transfer function has a resonance frequency at around 1 kHz, the stapes' response is almost constant for frequencies below the resonance and a roll-off is observed above the resonance. The tympanometry results show that the compliance of the middle ear model is similar to the compliance of a healthy human middle ear. We also present that we were able to manipulate the transmission behavior, so that healthy or pathological scenarios can be created. For this purpose we have built models with different mechanical properties by varying the hardness of the silicone rubber used for different structures, such as tympanic membrane, oval window and ossicle attachments in the range of Shore 10-40 A. This allowed us to set the transmission amplitudes in the plateau region higher, lower or within the tolerances of normal middle ears (Rosowski et al., 2007). Our results showed that it is possible to build an artificial model of the human middle ear by using 3D-printing technology in combination with silicone rubber molding. We were able to reproduce the anatomical shape of the middle ear's essential elements with high accuracy and also assemble them into a functioning middle ear model. The acoustic behavior of the model can be reproduced and manipulated by the choice of material. If the issues such as resonance of the casing and steep roll-off slope in higher frequencies can be solved, this model creates a reproducible environment for experiments and can be useful for the evaluation of prosthetic devices. Copyright © 2016 Elsevier B.V. All rights reserved.

Analytical and numerical solutions for mass diffusion in a composite cylindrical body

NASA Astrophysics Data System (ADS)

Kumar, A.

1980-12-01

The analytical and numerical solution techniques were investigated to study moisture diffusion problems in cylindrical bodies that are assumed to be composed of a finite number of layers of different materials. A generalized diffusion model for an n-layer cylindrical body with discontinuous moisture content at the interfaces was developed and the formal solutions were obtained. The model is to be used for describing mass transfer rates of any composite body, such as an ear of corn which could be assumed of consisting two different layers: the inner core represents the woody cob and the outer cylinder represents the kernel layer. Data describing the fully exposed drying characteristics of ear corn at high air velocity were obtained under different drying conditions. Ear corns were modeled as homogeneous bodies since composite model did not improve the fit substantially. A computer program using multidimensional optimization technique showed that diffusivity was an exponential function of moisture content and an arrhenius function of temperature of drying air.

Middle ear function and cochlear input impedance in chinchilla

PubMed Central

Slama, Michaël C. C.; Ravicz, Michael E.; Rosowski, John J.

2010-01-01

Simultaneous measurements of middle ear-conducted sound pressure in the cochlear vestibule PV and stapes velocity VS have been performed in only a few individuals from a few mammalian species. In this paper, simultaneous measurements of PV and VS in six chinchillas are reported, enabling computation of the middle ear pressure gain GME (ratio of PV to the sound pressure in the ear canal PTM), the stapes velocity transfer function SVTF (ratio of the product of VS and area of the stapes footplate AFP to PTM), and, for the first time, the cochlear input impedance ZC (ratio of PV to the product of VS and AFP) in individuals. |GME| ranged from 25 to 35 dB over 125 Hz–8 kHz; the average group delay between 200 Hz and 10 kHz was about 52 μs. SVTF was comparable to that of previous studies. ZC was resistive from the lowest frequencies up to at least 10 kHz, with a magnitude on the order of 1011 acoustic ohms. PV, VS, and the acoustic power entering the cochlea were good predictors of the shape of the audiogram at frequencies between 125 Hz and 2 kHz. PMID:20329840

Surgery of the ear and the lateral skull base: pitfalls and complications

PubMed Central

Schick, Bernhard; Dlugaiczyk, Julia

2013-01-01

Surgery of the ear and the lateral skull base is a fascinating, yet challenging field in otorhinolaryngology. A thorough knowledge of the associated complications and pitfalls is indispensable for the surgeon, not only to provide the best possible care to his patients, but also to further improve his surgical skills. Following a summary about general aspects in pre-, intra-and postoperative care of patients with disorders of the ear/lateral skull base, this article covers the most common pitfalls and complications in stapes surgery, cochlear implantation and surgery of vestibular schwannomas and jugulotympanal paragangliomas. Based on these exemplary procedures, basic “dos and don’ts” of skull base surgery are explained, which the reader can easily transfer to other disorders. Special emphasis is laid on functional aspects, such as hearing, balance and facial nerve function. Furthermore, the topics of infection, bleeding, skull base defects, quality of life and indication for revision surgery are discussed. An open communication about complications and pitfalls in ear/lateral skull base surgery among surgeons is a prerequisite for the further advancement of this fascinating field in ENT surgery. This article is meant to be a contribution to this process. PMID:24403973

[Complications and pitfalls in surgery of the ear/lateral skull base].

PubMed

Schick, B; Dlugaiczyk, J

2013-04-01

Surgery of the ear and the lateral skull base is a fascinating, yet challenging field in otorhinolaryngology. A thorough knowledge of the associated complications and pitfalls is indispensable for the surgeon, not only to provide the best possible care to his patients, but also to further improve his surgical skills.Following a summary about general aspects in pre-, intra- and postoperative care of patients with disorders of the ear/lateral skull base, this article covers the most common pitfalls and complications in stapes surgery, cochlear implantation, surgery of vestibular schwannomas, and jugulotympanal paragangliomas. Based on these exemplary procedures, basic "do's and don'ts" of skull base surgery are explained, which the reader can easily transfer to other disorders. Special emphasis is laid on functional aspects, such as hearing, balance and facial nerve function. Furthermore, the topics of infection, bleeding, skull base defects, quality of life and indication for revision surgery are discussed.An open communication about complications and pitfalls in ear/lateral skull base surgery among surgeons is a prerequisite for the further advancement of this fascinating field in ENT surgery. This article is meant to be a contribution to this process. © Georg Thieme Verlag KG Stuttgart · New York.

Cochlear implants and ex vivo BDNF gene therapy protect spiral ganglion neurons.

PubMed

Rejali, Darius; Lee, Valerie A; Abrashkin, Karen A; Humayun, Nousheen; Swiderski, Donald L; Raphael, Yehoash

2007-06-01

Spiral ganglion neurons often degenerate in the deaf ear, compromising the function of cochlear implants. Cochlear implant function can be improved by good preservation of the spiral ganglion neurons, which are the target of electrical stimulation by the implant. Brain derived neurotrophic factor (BDNF) has previously been shown to enhance spiral ganglion survival in experimentally deafened ears. Providing enhanced levels of BDNF in human ears may be accomplished by one of several different methods. The goal of these experiments was to test a modified design of the cochlear implant electrode that includes a coating of fibroblast cells transduced by a viral vector with a BDNF gene insert. To accomplish this type of ex vivo gene transfer, we transduced guinea pig fibroblasts with an adenovirus with a BDNF gene cassette insert, and determined that these cells secreted BDNF. We then attached BDNF-secreting cells to the cochlear implant electrode via an agarose gel, and implanted the electrode in the scala tympani. We determined that the BDNF expressing electrodes were able to preserve significantly more spiral ganglion neurons in the basal turns of the cochlea after 48 days of implantation when compared to control electrodes. This protective effect decreased in the higher cochlear turns. The data demonstrate the feasibility of combining cochlear implant therapy with ex vivo gene transfer for enhancing spiral ganglion neuron survival.

Wideband acoustic reflex test in a test battery to predict middle-ear dysfunction

PubMed Central

Keefe, Douglas H.; Fitzpatrick, Denis; Liu, Yi-Wen; Sanford, Chris A.; Gorga, Michael P.

2013-01-01

A wideband (WB) aural acoustical test battery of middle-ear status, including acoustic-reflex thresholds (ARTs) and acoustic-transfer functions (ATFs, i.e., absorbance and admittance) was hypothesized to be more accurate than 1-kHz tympanometry in classifying ears that pass or refer on a newborn hearing screening (NHS) protocol based on otoacoustic emissions. Assessment of middle-ear status may improve NHS programs by identifying conductive dysfunction and cases in which auditory neuropathy exists. Ipsilateral ARTs were assessed with a stimulus including four broadband-noise or tonal activator pulses alternating with five clicks presented before, between and after the pulses. The reflex shift was defined as the difference between final and initial click responses. ARTs were measured using maximum likelihood both at low frequencies (0.8–2.8 kHz) and high (2.8–8 kHz). The median low-frequency ART was elevated by 24 dB in NHS refers compared to passes. An optimal combination of ATF and ART tests performed better than either test alone in predicting NHS outcomes, and WB tests performed better than 1-kHz tympanometry. Medial olivocochlear efferent shifts in cochlear function may influence ARs, but their presence would also be consistent with normal conductive function. Baseline clinical and WB ARTs were also compared in ipsilateral and contralateral measurements in adults. PMID:19772907

Position-dependent hearing in three species of bushcrickets (Tettigoniidae, Orthoptera)

PubMed Central

Lakes-Harlan, Reinhard; Scherberich, Jan

2015-01-01

A primary task of auditory systems is the localization of sound sources in space. Sound source localization in azimuth is usually based on temporal or intensity differences of sounds between the bilaterally arranged ears. In mammals, localization in elevation is possible by transfer functions at the ear, especially the pinnae. Although insects are able to locate sound sources, little attention is given to the mechanisms of acoustic orientation to elevated positions. Here we comparatively analyse the peripheral hearing thresholds of three species of bushcrickets in respect to sound source positions in space. The hearing thresholds across frequencies depend on the location of a sound source in the three-dimensional hearing space in front of the animal. Thresholds differ for different azimuthal positions and for different positions in elevation. This position-dependent frequency tuning is species specific. Largest differences in thresholds between positions are found in Ancylecha fenestrata. Correspondingly, A. fenestrata has a rather complex ear morphology including cuticular folds covering the anterior tympanal membrane. The position-dependent tuning might contribute to sound source localization in the habitats. Acoustic orientation might be a selective factor for the evolution of morphological structures at the bushcricket ear and, speculatively, even for frequency fractioning in the ear. PMID:26543574

Position-dependent hearing in three species of bushcrickets (Tettigoniidae, Orthoptera).

PubMed

Lakes-Harlan, Reinhard; Scherberich, Jan

2015-06-01

A primary task of auditory systems is the localization of sound sources in space. Sound source localization in azimuth is usually based on temporal or intensity differences of sounds between the bilaterally arranged ears. In mammals, localization in elevation is possible by transfer functions at the ear, especially the pinnae. Although insects are able to locate sound sources, little attention is given to the mechanisms of acoustic orientation to elevated positions. Here we comparatively analyse the peripheral hearing thresholds of three species of bushcrickets in respect to sound source positions in space. The hearing thresholds across frequencies depend on the location of a sound source in the three-dimensional hearing space in front of the animal. Thresholds differ for different azimuthal positions and for different positions in elevation. This position-dependent frequency tuning is species specific. Largest differences in thresholds between positions are found in Ancylecha fenestrata. Correspondingly, A. fenestrata has a rather complex ear morphology including cuticular folds covering the anterior tympanal membrane. The position-dependent tuning might contribute to sound source localization in the habitats. Acoustic orientation might be a selective factor for the evolution of morphological structures at the bushcricket ear and, speculatively, even for frequency fractioning in the ear.

Development and Current Status of the “Cambridge” Loudness Models

PubMed Central

2014-01-01

This article reviews the evolution of a series of models of loudness developed in Cambridge, UK. The first model, applicable to stationary sounds, was based on modifications of the model developed by Zwicker, including the introduction of a filter to allow for the effects of transfer of sound through the outer and middle ear prior to the calculation of an excitation pattern, and changes in the way that the excitation pattern was calculated. Later, modifications were introduced to the assumed middle-ear transfer function and to the way that specific loudness was calculated from excitation level. These modifications led to a finite calculated loudness at absolute threshold, which made it possible to predict accurately the absolute thresholds of broadband and narrowband sounds, based on the assumption that the absolute threshold corresponds to a fixed small loudness. The model was also modified to give predictions of partial loudness—the loudness of one sound in the presence of another. This allowed predictions of masked thresholds based on the assumption that the masked threshold corresponds to a fixed small partial loudness. Versions of the model for time-varying sounds were developed, which allowed prediction of the masked threshold of any sound in a background of any other sound. More recent extensions incorporate binaural processing to account for the summation of loudness across ears. In parallel, versions of the model for predicting loudness for hearing-impaired ears have been developed and have been applied to the development of methods for fitting multichannel compression hearing aids. PMID:25315375

Vestibular regeneration--experimental models and clinical implications.

PubMed

Albu, Silviu; Muresanu, Dafin F

2012-09-01

Therapies aimed at the protection and/or regeneration of inner ear hair cells are of great interest, given the significant monetary and quality of life impact of balance disorders. Different viral vectors have been shown to transfect various cell types in the inner ear. The past decade has provided tremendous advances in the use of adenoviral vectors to achieve targeted treatment delivery. Several routes of delivery have been identified to introduce vectors into the inner ear while minimizing injury to surrounding structures. Recently, the transcription factor Atoh1 was determined to play a critical role in hair cell differentiation. Adenoviral-mediated overexpression of Atoh1 in culture and in vivo has demonstrated the ability to regenerate vestibular hair cells by causing transdifferentiation of neighbouring epithelial-supporting cells. Functional recovery of the vestibular system has also been documented following adenoviral-induced Atoh1 overexpression. Experiments demonstrating gene transfer in human vestibular epithelial cells reveal that the human inner ear is a suitable target for gene therapy. © 2012 The Authors Journal of Cellular and Molecular Medicine © 2012 Foundation for Cellular and Molecular Medicine/Blackwell Publishing Ltd.

Specification of absorbed-sound power in the ear canal: Application to suppression of stimulus frequency otoacoustic emissions

PubMed Central

Keefe, Douglas H.; Schairer, Kim S.

2011-01-01

An insert ear-canal probe including sound source and microphone can deliver a calibrated sound power level to the ear. The aural power absorbed is proportional to the product of mean-squared forward pressure, ear-canal area, and absorbance, in which the sound field is represented using forward (reverse) waves traveling toward (away from) the eardrum. Forward pressure is composed of incident pressure and its multiple internal reflections between eardrum and probe. Based on a database of measurements in normal-hearing adults from 0.22 to 8 kHz, the transfer-function level of forward relative to incident pressure is boosted below 0.7 kHz and within 4 dB above. The level of forward relative to total pressure is maximal close to 4 kHz with wide variability across ears. A spectrally flat incident-pressure level across frequency produces a nearly flat absorbed power level, in contrast to 19 dB changes in pressure level. Calibrating an ear-canal sound source based on absorbed power may be useful in audiological and research applications. Specifying the tip-to-tail level difference of the suppression tuning curve of stimulus frequency otoacoustic emissions in terms of absorbed power reveals increased cochlear gain at 8 kHz relative to the level difference measured using total pressure. PMID:21361437

Effects of consecutive wideband tympanometry trials on energy absorbance measures of the middle ear.

PubMed

Burdiek, Laina M; Sun, Xiao-Ming

2014-10-01

Wideband acoustic immittance (WAI) is a new technique for assessing middle ear transfer function. It includes energy absorbance (EA) measures and can be acquired with the ear canal pressure varied, known as wideband tympanometry (WBTymp). The authors of this study aimed to investigate effects of consecutive WBTymp testing on EA. Data were collected in 29 young adults with normal hearing and middle ear status. Before and after 8 successive WBTymp runs, EA was also measured at ambient pressure. Subsequently, two 226-Hz tympanometry tests were performed. EA systematically changed over the WBTymp trials in a frequency-specific manner: increase for low frequencies (below 1.5 kHz) and decrease for high frequencies (around 2 kHz and 5 to 6 kHz). The changes, although small, were significant. Much larger EA changes were measured at ambient pressure. The test-retest difference of 226-Hz tympanogram measures was much smaller than previously reported. Consecutive tympanometry testing alters EA measures of the middle ear. This phenomenon could be mainly attributed to change in stiffness at the eardrum, called tympanometric preconditioning. This also has effects on baseline WBTymp outcomes. This effect should be taken into account as a procedural variable in both research and clinical applications of WAI measurements.

A new malleostapedotomy prosthesis. Experimental analysis by laser doppler vibrometer in fresh cadaver temporal bones.

PubMed

Vallejo, Luis A; Manzano, María T; Hidalgo, Antonio; Hernández, Alberto; Sabas, Juan; Lara, Hugo; Gil-Carcedo, Elisa; Herrero, David

One of the problems with total ossicular replacement prostheses is their stability. Prosthesis dislocations and extrusions are common in middle ear surgery. This is due to variations in endo-tympanic pressure as well as design defects. The design of this new prosthesis reduces this problem by being joined directly to the malleus handle. The aim of this study is to confirm adequate acoustic-mechanical behaviour in fresh cadaver middle ear of a new total ossicular replacement prosthesis, designed using the finite elements method. Using the doppler vibrometer laser, we analysed the acoustic-mechanical behaviour of a new total ossicular replacement prosthesis in the human middle ear using 10 temporal bones from fresh cadavers. The transfer function of the ears in which we implanted the new prosthesis was superimposed over the non-manipulated ear. This suggests optimum acoustic-mechanical behaviour. The titanium prosthesis analysed in this study demonstrated optimum acoustic-mechanical behaviour. Together with its ease of implantation and post-surgical stability, these factors make it a prosthesis to be kept in mind in ossicular reconstruction. Copyright © 2016 Elsevier España, S.L.U. and Sociedad Española de Otorrinolaringología y Cirugía de Cabeza y Cuello. All rights reserved.

Post interaural neural net-based vowel recognition

NASA Astrophysics Data System (ADS)

Jouny, Ismail I.

2001-10-01

Interaural head related transfer functions are used to process speech signatures prior to neural net based recognition. Data representing the head related transfer function of a dummy has been collected at MIT and made available on the Internet. This data is used to pre-process vowel signatures to mimic the effects of human ear on speech perception. Signatures representing various vowels of the English language are then presented to a multi-layer perceptron trained using the back propagation algorithm for recognition purposes. The focus in this paper is to assess the effects of human interaural system on vowel recognition performance particularly when using a classification system that mimics the human brain such as a neural net.

Hearing Science in Mid-Eighteenth-Century Britain and France

PubMed Central

Gouk, Penelope; Sykes, Ingrid

2011-01-01

Benjamin Martin, the English natural philosopher, and Claude-Nicolas Le Cat, the French surgeon, both published important work on auditory physiology and function in the mid-eighteenth century. Despite their different backgrounds, there was consensus between the two scholars on key principles of hearing research, most notably the importance of the inner ear in relation to auditory perception. Martin's work (1755 [1763?]) drew directly on the surgical work of Le Cat (1741) to demonstrate the importance of the auditory mechanism in listening processes. Le Cat's interest in the ear, however, came in turn from his interest in surgical anatomy. Martin used Le Cat's elegant designs as a tool for the vivid communication of auditory function to a popular, fee-paying audience. The meeting of two very different minds through intellectual agreement and material transfer demonstrates the way in which principles of hearing science were established in the Enlightenment period. PMID:20634220

Hearing science in mid-eighteenth-century Britain and France.

PubMed

Gouk, Penelope; Sykes, Ingrid

2011-10-01

Benjamin Martin, the English natural philosopher, and Claude-Nicolas Le Cat, the French surgeon, both published important work on auditory physiology and function in the mid-eighteenth century. Despite their different backgrounds, there was consensus between the two scholars on key principles of hearing research, most notably the importance of the inner ear in relation to auditory perception. Martin's work (1755 [1763?]) drew directly on the surgical work of Le Cat (1741) to demonstrate the importance of the auditory mechanism in listening processes. Le Cat's interest in the ear, however, came in turn from his interest in surgical anatomy. Martin used Le Cat's elegant designs as a tool for the vivid communication of auditory function to a popular, fee-paying audience. The meeting of two very different minds through intellectual agreement and material transfer demonstrates the way in which principles of hearing science were established in the Enlightenment period.

Privacy-protected biometric templates: acoustic ear identification

NASA Astrophysics Data System (ADS)

Tuyls, Pim T.; Verbitskiy, Evgeny; Ignatenko, Tanya; Schobben, Daniel; Akkermans, Ton H.

2004-08-01

Unique Biometric Identifiers offer a very convenient way for human identification and authentication. In contrast to passwords they have hence the advantage that they can not be forgotten or lost. In order to set-up a biometric identification/authentication system, reference data have to be stored in a central database. As biometric identifiers are unique for a human being, the derived templates comprise unique, sensitive and therefore private information about a person. This is why many people are reluctant to accept a system based on biometric identification. Consequently, the stored templates have to be handled with care and protected against misuse [1, 2, 3, 4, 5, 6]. It is clear that techniques from cryptography can be used to achieve privacy. However, as biometric data are noisy, and cryptographic functions are by construction very sensitive to small changes in their input, and hence one can not apply those crypto techniques straightforwardly. In this paper we show the feasibility of the techniques developed in [5], [6] by applying them to experimental biometric data. As biometric identifier we have choosen the shape of the inner ear-canal, which is obtained by measuring the headphone-to-ear-canal Transfer Functions (HpTFs) which are known to be person dependent [7].

Vestibular sensory functional status of cochlear implanted ears versus non-implanted ears in bilateral profound deaf adults.

PubMed

Cozma, Romică Sebastian; Dima-Cozma, Lucia Corina; Rădulescu, Luminiţa Mihaela; Hera, Maria Cristina; Mârţu, Cristian; Olariu, Raluca; Cobzeanu, Bogdan Mihail; Bitere, Oana Roxana; Cobzeanu, Mihail Dan

2018-01-01

Patients with hearing loss who underwent cochlear implantation can present symptomatic or asymptomatic vestibular damages earlier or later after the surgery. The vestibular permanent lesions could be acute, produced by surgical trauma or could be progressive due to local morphological changes made by the presence of the portelectrode in the inner ear (fibrosis related, ossification, basilar membrane distortion, endolymphatic hydrops). Besides histopathological findings in inner ear of cochlear implanted patients, the vestibular permanent damages could be found by assessment of clinical vestibular status. This study reports the sensorial vestibular functional findings for adults in cochlear implanted ears related to the electrode insertion type (cochleostomy or round window approach) and comparing to non-implanted deaf ears. A total of 20 adult patients with 32 cochlear implanted ears (12 patients with binaural cochlear implant and eight with monoaural) were selected for postoperatory vestibular examination by cervical and ocular vestibular myogenic potentials and vestibular caloric tests. The same tests were made for a control group of 22 non-implanted deaf ears. Functional testing results were reported related to the electrode insertion approach. For the cochleostomy group, we found different deficits: in 40% for saccular function, 44% for utricular function, and 12% horizontal canal dysfunction. In round window group, the deficit was present in 14.29% for saccular function, 28.57% for utricular function, and 28.58% for horizontal canal. In 46.88% of implanted ears, the vestibular function was completely preserved on all tested sensors. In conclusion, the vestibular functional status after inner ear surgery presents sensorial damages in 53.12% ears compare with the vestibular dysfunction existing in 50% of deaf non-operated ears. Round window insertion allows for better conservation of the vestibular function.

Effect of middle ear fluid on sound transmission and auditory brainstem response in guinea pigs.

PubMed

Guan, Xiying; Gan, Rong Z

2011-07-01

Combined measurements of middle ear transfer function and auditory brainstem response (ABR) in live guinea pigs with middle ear effusion (MEE) are reported in this paper. The MEE model was created by injecting saline into the middle ear cavity. Vibrations of the tympanic membrane (TM), the tip of the incus, and the round window membrane (RWM) were measured with a laser vibrometer at frequencies of 0.2-40 kHz when the middle ear fluid increased from 0 to 0.2 ml (i.e., full fill of the cavity). The click and pure tone ABRs were recorded as the middle ear fluid increased. Fluid introduction reduced mobility of the TM, incus and RWM mainly at high frequencies (f > 1 kHz). The magnitude of this reduction was related to the volume of fluid. The displacement transmission ratio of the TM to incus varied with frequency and fluid level. The volume displacement ratio of the oval window to round window was approximately 1.0 over most frequencies. Elevation of ABR thresholds and prolongation of ABR latencies were observed as fluid level increased. Reduction of TM displacement correlated well with elevation of ABR threshold at 0.5-8 kHz. Alterations in the ratio of ossicular displacements before and after fluid induction are consistent with fluid-induced changes in complex ossicular motions. Copyright © 2011 Elsevier B.V. All rights reserved.

Biomechanical Analysis of Hearing in Whales Using Nanoindentation and the Finite Element Method

NASA Astrophysics Data System (ADS)

Tubelli, Andrew A.; Zosuls, Aleks; Ketten, Darlene R.; Mountain, David C.

2011-11-01

The detailed biomechanics of hearing in baleen whales are almost entirely unknown. As a first step to predicting the audiogram for these species, a linear three-dimensional finite-element model of the minke whale (Balaenoptera acutorostrata) middle ear was developed. A reconstruction of the ear was made from CT scans and imported into a finite element solver. Young's modulus of the bone was estimated via nanoindentation. The middle-ear transfer function was estimated by applying a pressure to the glove finger (the thick, everted equivalent of the tympanic membrane) with velocity calculated at the stapes footplate. It was found that the most sensitive frequencies corresponded with vocalization frequencies. For all frequencies tested, the malleus-incus complex flexed about the anterior process of the malleus and the stapes rotated within the oval window. Results indictae that finite element modeling is a useful approach for studying the mechanics of hearing in species that are difficult to study in vivo.

Inverse solution of ear-canal area function from reflectance

PubMed Central

Rasetshwane, Daniel M.; Neely, Stephen T.

2011-01-01

A number of acoustical applications require the transformation of acoustical quantities, such as impedance and pressure that are measured at the entrance of the ear canal, to quantities at the eardrum. This transformation often requires knowledge of the shape of the ear canal. Previous attempts to measure ear-canal area functions were either invasive, non-reproducible, or could only measure the area function up to a point mid-way along the canal. A method to determine the area function of the ear canal from measurements of acoustic impedance at the entrance of the ear canal is described. The method is based on a solution to the inverse problem in which measurements of impedance are used to calculate reflectance, which is then used to determine the area function of the canal. The mean ear-canal area function determined using this method is similar to mean ear-canal area functions measured by other researchers using different techniques. The advantage of the proposed method over previous methods is that it is non- invasive, fast, and reproducible. PMID:22225043

[Transitory evoked otoacoustic emissions and distortion product emissions in disorders of middle ear ventilation].

PubMed

Schmuziger, N; Hauser, R; Probst, R

1996-06-01

Both the amplitude and power spectra of otoacoustic emissions are affected by the transfer properties of the middle ear. This prospective study examined the influence of eustachian tube dysfunction on transiently evoked otoacoustic emissions (TEOAEs) and distortion-product otoacoustic emissions (DPOAEs). In all, 18 ears were studied that exhibited negative middle ear pressures with or without middle ear fluid. Measurements were performed at the time of diagnosis during the recovery stage, and after the middle ear became normally ventilated. Findings showed that TEOAE and DPOAE levels increased while airbone gaps were reduced by an average of 8 dB after negative middle ear pressures returned from -400 daPa to a normal state. There was a tendency for negative middle ear pressure to affect DPOAEs more in the 1-kHz region than in higher frequencies. By contrast, TEOAEs and airbone gaps were more uniformly affected across the entire frequency range. These results for ears with eustachian tube dysfunction were somewhat different from those results of studies obtained in healthy ears tested during experimental changes in middle ear pressure.

Interhemispheric transfer time in patients with auditory hallucinations: an auditory event-related potential study.

PubMed

Henshall, Katherine R; Sergejew, Alex A; McKay, Colette M; Rance, Gary; Shea, Tracey L; Hayden, Melissa J; Innes-Brown, Hamish; Copolov, David L

2012-05-01

Central auditory processing in schizophrenia patients with a history of auditory hallucinations has been reported to be impaired, and abnormalities of interhemispheric transfer have been implicated in these patients. This study examined interhemispheric functional connectivity between auditory cortical regions, using temporal information obtained from latency measures of the auditory N1 evoked potential. Interhemispheric Transfer Times (IHTTs) were compared across 3 subject groups: schizophrenia patients who had experienced auditory hallucinations, schizophrenia patients without a history of auditory hallucinations, and normal controls. Pure tones and single-syllable words were presented monaurally to each ear, while EEG was recorded continuously. IHTT was calculated for each stimulus type by comparing the latencies of the auditory N1 evoked potential recorded contralaterally and ipsilaterally to the ear of stimulation. The IHTTs for pure tones did not differ between groups. For word stimuli, the IHTT was significantly different across the 3 groups: the IHTT was close to zero in normal controls, was highest in the AH group, and was negative (shorter latencies ipsilaterally) in the nonAH group. Differences in IHTTs may be attributed to transcallosal dysfunction in the AH group, but altered or reversed cerebral lateralization in nonAH participants is also possible. Copyright © 2012 Elsevier B.V. All rights reserved.

Probing the Xenopus laevis inner ear transcriptome for biological function

PubMed Central

2012-01-01

Background The senses of hearing and balance depend upon mechanoreception, a process that originates in the inner ear and shares features across species. Amphibians have been widely used for physiological studies of mechanotransduction by sensory hair cells. In contrast, much less is known of the genetic basis of auditory and vestibular function in this class of animals. Among amphibians, the genus Xenopus is a well-characterized genetic and developmental model that offers unique opportunities for inner ear research because of the amphibian capacity for tissue and organ regeneration. For these reasons, we implemented a functional genomics approach as a means to undertake a large-scale analysis of the Xenopus laevis inner ear transcriptome through microarray analysis. Results Microarray analysis uncovered genes within the X. laevis inner ear transcriptome associated with inner ear function and impairment in other organisms, thereby supporting the inclusion of Xenopus in cross-species genetic studies of the inner ear. The use of gene categories (inner ear tissue; deafness; ion channels; ion transporters; transcription factors) facilitated the assignment of functional significance to probe set identifiers. We enhanced the biological relevance of our microarray data by using a variety of curation approaches to increase the annotation of the Affymetrix GeneChip® Xenopus laevis Genome array. In addition, annotation analysis revealed the prevalence of inner ear transcripts represented by probe set identifiers that lack functional characterization. Conclusions We identified an abundance of targets for genetic analysis of auditory and vestibular function. The orthologues to human genes with known inner ear function and the highly expressed transcripts that lack annotation are particularly interesting candidates for future analyses. We used informatics approaches to impart biologically relevant information to the Xenopus inner ear transcriptome, thereby addressing the impediment imposed by insufficient gene annotation. These findings heighten the relevance of Xenopus as a model organism for genetic investigations of inner ear organogenesis, morphogenesis, and regeneration. PMID:22676585

Functional relevance of interindividual differences in temporal lobe callosal pathways: a DTI tractography study.

PubMed

Westerhausen, René; Grüner, Renate; Specht, Karsten; Hugdahl, Kenneth

2009-06-01

The midsagittal corpus callosum is topographically organized, that is, with regard to their cortical origin several subtracts can be distinguished within the corpus callosum that belong to specific functional brain networks. Recent diffusion tensor tractography studies have also revealed remarkable interindividual differences in the size and exact localization of these tracts. To examine the functional relevance of interindividual variability in callosal tracts, 17 right-handed male participants underwent structural and diffusion tensor magnetic resonance imaging. Probabilistic tractography was carried out to identify the callosal subregions that interconnect left and right temporal lobe auditory processing areas, and the midsagittal size of this tract was seen as indicator of the (anatomical) strength of this connection. Auditory information transfer was assessed applying an auditory speech perception task with dichotic presentations of consonant-vowel syllables (e.g., /ba-ga/). The frequency of correct left ear reports in this task served as a functional measure of interhemispheric transfer. Statistical analysis showed that a stronger anatomical connection between the superior temporal lobe areas supports a better information transfer. This specific structure-function association in the auditory modality supports the general notion that interindividual differences in callosal topography possess functional relevance.

Why Do Elephants Flap Their Ears?

NASA Astrophysics Data System (ADS)

Koffi, Moise; Jiji, Latif; Andreopoulos, Yiannis

2009-11-01

It is estimated that a 4200 kg elephant generates as much as 5.12 kW of heat. How the elephant dissipates its metabolic heat and regulates its body temperature has been investigated during the past seven decades. Findings and conclusions differ sharply. The high rate of metabolic heat coupled with low surface area to volume ratio and the absence of sweat glands eliminate surface convection as the primary mechanism for heat removal. Noting that the elephant ears have high surface area to volume ratio and an extensive vascular network, ear flapping is thought to be the principal thermoregulatory mechanism. A computational and experimental program is carried out to examine flow and heat transfer characteristics. The ear is modeled as a uniformly heated oscillating rectangular plate. Our computational work involves a three-dimensional time dependent CFD code with heat transfer capabilities to obtain predictions of the flow field and surface temperature distributions. This information was used to design an experimental setup with a uniformly heated plate of size 0.2m x 0.3m oscillating at 1.6 cycles per second. Results show that surface temperature increases and reaches a steady periodic oscillation after a period of transient oscillation. The role of the vortices shed off the plate in heat transfer enhancement will be discussed.

Neural field theory of perceptual echo and implications for estimating brain connectivity

NASA Astrophysics Data System (ADS)

Robinson, P. A.; Pagès, J. C.; Gabay, N. C.; Babaie, T.; Mukta, K. N.

2018-04-01

Neural field theory is used to predict and analyze the phenomenon of perceptual echo in which random input stimuli at one location are correlated with electroencephalographic responses at other locations. It is shown that this echo correlation (EC) yields an estimate of the transfer function from the stimulated point to other locations. Modal analysis then explains the observed spatiotemporal structure of visually driven EC and the dominance of the alpha frequency; two eigenmodes of similar amplitude dominate the response, leading to temporal beating and a line of low correlation that runs from the crown of the head toward the ears. These effects result from mode splitting and symmetry breaking caused by interhemispheric coupling and cortical folding. It is shown how eigenmodes obtained from functional magnetic resonance imaging experiments can be combined with temporal dynamics from EC or other evoked responses to estimate the spatiotemporal transfer function between any two points and hence their effective connectivity.

Real-time loudness normalisation with combined cochlear implant and hearing aid stimulation

PubMed Central

Van Eeckhoutte, Maaike; Van Deun, Lieselot; Francart, Tom

2018-01-01

Background People who use a cochlear implant together with a contralateral hearing aid—so-called bimodal listeners—have poor localisation abilities and sounds are often not balanced in loudness across ears. In order to address the latter, a loudness balancing algorithm was created, which equalises the loudness growth functions for the two ears. The algorithm uses loudness models in order to continuously adjust the two signals to loudness targets. Previous tests demonstrated improved binaural balance, improved localisation, and better speech intelligibility in quiet for soft phonemes. In those studies, however, all stimuli were preprocessed so spontaneous head movements and individual head-related transfer functions were not taken into account. Furthermore, the hearing aid processing was linear. Study design In the present study, we simplified the acoustical loudness model and implemented the algorithm in a real-time system. We tested bimodal listeners on speech perception and on sound localisation, both in normal loudness growth configuration and in a configuration with a modified loudness growth function. We also used linear and compressive hearing aids. Results The comparison between the original acoustical loudness model and the new simplified model showed loudness differences below 3% for almost all tested speech-like stimuli and levels. We found no effect of balancing the loudness growth across ears for speech perception ability in quiet and in noise. We found some small improvements in localisation performance. Further investigation with a larger sample size is required. PMID:29617421

The VEGF-C/VEGFR3 signaling pathway contributes to resolving chronic skin inflammation by activating lymphatic vessel function.

PubMed

Hagura, Asami; Asai, Jun; Maruyama, Kazuichi; Takenaka, Hideya; Kinoshita, Shigeru; Katoh, Norito

2014-02-01

The functions of lymphatic vessels are to drain the protein-rich lymph from the extracellular space, to maintain normal tissue pressure, and to mediate the immune response, particularly in inflammatory conditions. To evaluate the function of the vascular endothelial growth factor (VEGF)-C/VEGF receptor (VEGFR)-3 signaling pathway in chronic skin inflammation. We used adenovirus-mediated VEGF-C or VEGFR3-immunoglobulin (Ig) production and investigated the effects of VEGF-C/VEGFR3 signaling on the resolution of inflammation using the experimental chronic contact hypersensitivity (CHS) reaction mouse model. VEGF-C gene transfer promoted significant reduction of ear swelling and ear weight in CHS reaction-induced skin inflammation. Although, there was no significant difference in the number of lymphatic vessels, the number of infiltrating CD11b-positive inflammatory cells was significantly reduced in the VEGF-C group, which suggested that VEGF-C upregulated the drainage of interstitial fluid and inflammatory cells via lymphatic vessels. Furthermore, blockade of VEGFR3 expression resulted in a significant delay in the recovery from CHS reaction-induced skin inflammation. Lymphatic vessel size was enlarged and a significant increase of infiltrating CD11b inflammatory cells was observed in mice with VEGFR3-Ig gene transfer compared to control mice. These results suggested that blockade of VEGFR3 inhibited the drainage function of the lymphatic system. This study provides evidence that VEGF-C/VEGFR3 signaling plays an important role in the resolution of skin inflammation; the regulation of lymphatic function may have a great therapeutic potential in inflammatory skin diseases. Copyright © 2013 Japanese Society for Investigative Dermatology. Published by Elsevier Ireland Ltd. All rights reserved.

Influence of the middle ear anatomy on the performance of a membrane sensor in the incudostapedial joint gap.

PubMed

Koch, Martin; Seidler, Hannes; Hellmuth, Alexander; Bornitz, Matthias; Lasurashvili, Nikoloz; Zahnert, Thomas

2013-07-01

There is a great demand for implantable microphones for future generations of implantable hearing aids, especially Cochlea Implants. An implantable middle ear microphone based on a piezoelectric membrane sensor for insertion into the incudostapedial gap is investigated. The sensor is designed to measure the sound-induced forces acting on the center of the membrane. The sensor mechanically couples to the adjacent ossicles via two contact areas, the sensor membrane and the sensor housing. The sensing element is a piezoelectric single crystal bonded on a titanium membrane. The sensor allows a minimally invasive and reversible implantation without removal of ossicles and without additional sensor fixation in the tympanic cavity. This study investigates the implantable microphone sensor and its implantation concept. It intends to quantify the influence of the sensor's insertion position on the achievable microphone sensitivity. The investigation considers anatomical and pathological variations of the middle ear geometry and its space limitations. Temporal bone experiments on a laboratory model show that anatomical and pathological variations of the middle ear geometry can prevent the sensor from being placed optimally within the incudostapedial joint. Beyond scattering of transfer functions due to anatomic variations of individual middle ears there is the impact of variations in the sensor position within the ossicular chain that has a considerable effect on the transfer characteristics of the middle ear microphone. The centering of the sensor between incus and stapes, the direction of insertion (membrane to stapes or to incus) and the effect of additional contact points with surrounding anatomic structures affect the signal yield of the implanted sensor. The presence of additional contact points has a considerably impact on the sensitivity, yet the microphone sensitivity is quite robust against small changes in the positioning of the incus on the sensor. Signal losses can be avoided by adjusting the position of the sensor within the joint. The findings allow the development of an improved surgical insertion technique to ensure maximally achievable signal yield of the membrane sensor in the ISJ and provides valuable knowledge for a future design considerations including sensor miniaturization and geometry. Measurements of the implanted sensor in temporal bone specimens showed a microphone sensitivity in the order of 1 mV/Pa. This article is part of a special issue entitled "MEMRO 2012". Copyright © 2012 Elsevier B.V. All rights reserved.

Finite element modelling of sound transmission from outer to inner ear.

PubMed

Areias, Bruno; Santos, Carla; Natal Jorge, Renato M; Gentil, Fernanda; Parente, Marco Pl

2016-11-01

The ear is one of the most complex organs in the human body. Sound is a sequence of pressure waves, which propagates through a compressible media such as air. The pinna concentrates the sound waves into the external auditory meatus. In this canal, the sound is conducted to the tympanic membrane. The tympanic membrane transforms the pressure variations into mechanical displacements, which are then transmitted to the ossicles. The vibration of the stapes footplate creates pressure waves in the fluid inside the cochlea; these pressure waves stimulate the hair cells, generating electrical signals which are sent to the brain through the cochlear nerve, where they are decoded. In this work, a three-dimensional finite element model of the human ear is developed. The model incorporates the tympanic membrane, ossicular bones, part of temporal bone (external auditory meatus and tympanic cavity), middle ear ligaments and tendons, cochlear fluid, skin, ear cartilage, jaw and the air in external auditory meatus and tympanic cavity. Using the finite element method, the magnitude and the phase angle of the umbo and stapes footplate displacement are calculated. Two slightly different models are used: one model takes into consideration the presence of air in the external auditory meatus while the other does not. The middle ear sound transfer function is determined for a stimulus of 60 dB SPL, applied to the outer surface of the air in the external auditory meatus. The obtained results are compared with previously published data in the literature. This study highlights the importance of external auditory meatus in the sound transmission. The pressure gain is calculated for the external auditory meatus.

Eustachian tube function and middle ear barotrauma associated with extremes in atmospheric pressure.

PubMed

Miyazawa, T; Ueda, H; Yanagita, N

1996-11-01

Eustachian tube (ET) function was studied by means of sonotubometry and tubotympano-aerodynamography (TTAG) prior to and following exposure to hypobaric or hyperbaric conditions. Forty normal adults were subjected to hypobaric pressure. Fifty adults who underwent hyperbaric oxygen (HBO) therapy also were studied. Following hypobaric exposure, 14 of 80 ears (17.5%) exhibited middle ear barotrauma. Following hyperbaric exposure, 34 of 100 ears (34%) exhibited middle ear barotrauma. Dysfunction of the ET, characterized by altered active and passive opening capacity, was more prevalent following exposure to extremes in atmospheric pressure compared to baseline. The ET function, which was impaired after the first HBO treatment, improved gradually over the next 2 hours. Overall, however, ET function was worse after the seventh treatment. The patients who developed barotrauma exhibited worse ET function prior to hypobaric or hyperbaric exposure. Thus, abnormal ET function can be used to predict middle ear barotrauma prior to exposure to hypobaric or hyperbaric atmospheric pressure.

Physiological functioning of the ear and masking

NASA Technical Reports Server (NTRS)

1984-01-01

The physiological functions of the ear and the role masking plays in speech communication are examined. Topics under investigation include sound analysis of the ear, the aural reflex, and various types of noise masking.

A review of gene delivery and stem cell based therapies for regenerating inner ear hair cells.

PubMed

Devarajan, Keerthana; Staecker, Hinrich; Detamore, Michael S

2011-09-13

Sensory neural hearing loss and vestibular dysfunction have become the most common forms of sensory defects, affecting millions of people worldwide. Developing effective therapies to restore hearing loss is challenging, owing to the limited regenerative capacity of the inner ear hair cells. With recent advances in understanding the developmental biology of mammalian and non-mammalian hair cells a variety of strategies have emerged to restore lost hair cells are being developed. Two predominant strategies have developed to restore hair cells: transfer of genes responsible for hair cell genesis and replacement of missing cells via transfer of stem cells. In this review article, we evaluate the use of several genes involved in hair cell regeneration, the advantages and disadvantages of the different viral vectors employed in inner ear gene delivery and the insights gained from the use of embryonic, adult and induced pluripotent stem cells in generating inner ear hair cells. Understanding the role of genes, vectors and stem cells in therapeutic strategies led us to explore potential solutions to overcome the limitations associated with their use in hair cell regeneration.

Iterated intracochlear reflection shapes the envelopes of basilar-membrane click responses

PubMed Central

Shera, Christopher A.

2015-01-01

Multiple internal reflection of cochlear traveling waves has been argued to provide a plausible explanation for the waxing and waning and other temporal structures often exhibited by the envelopes of basilar-membrane (BM) and auditory-nerve responses to acoustic clicks. However, a recent theoretical analysis of a BM click response measured in chinchilla concludes that the waveform cannot have arisen via any equal, repetitive process, such as iterated intracochlear reflection [Wit and Bell (2015), J. Acoust. Soc. Am. 138, 94–96]. Reanalysis of the waveform contradicts this conclusion. The measured BM click response is used to derive the frequency-domain transfer function characterizing every iteration of the loop. The selfsame transfer function that yields waxing and waning of the BM click response also captures the spectral features of ear-canal stimulus-frequency otoacoustic emissions measured in the same animal, consistent with the predictions of multiple internal reflection. Small shifts in transfer-function phase simulate results at different measurement locations and reproduce the heterogeneity of BM click response envelopes observed experimentally. PMID:26723327

Analysis of earing behaviour in deep drawing of ASS 304 at elevated temperature

NASA Astrophysics Data System (ADS)

Gupta, Amit Kumar; Deole, Aditya; Kotkunde, Nitin; Singh, Swadesh Kumar; jella, Gangadhar

2016-08-01

Earing tendency in a deep drawn cup of circular blanks is one the most prominent characteristics observed due to anisotropy in a metal sheet. Such formation of uneven rim is mainly due to dissimilarity in yield stress as well as Lankford parameter (r- value) in different orientations. In this paper, an analytical function coupled with different yield functions viz., Hill 1948, Barlat 1989 and Barlat Yld 2000-2d has been used to provide an approximation of earing profile. In order to validate the results, material parameters for yield functions and hardening rule have been calibrated for ASS 304 at 250°C and deep drawing experiment is conducted to measure the earing profile. The predicted earing profiles based on analytical results have been validated using experimental earing profile. Based on this analysis, Barlat Yld 2000-2d has been observed to be a well suited yield model for deep drawing of ASS 304, which also confirms the reliability of analytical function for earing profile estimation.

Experimental exposure of eggs to polybrominated diphenyl ethers BDE-47 and BDE-99 in red-eared sliders (Trachemys scripta elegans) and snapping turtles (Chelydra serpentina) and possible species-specific differences in debromination.

PubMed

Eisenreich, Karen M; Rowe, Christopher L

2013-02-01

Polybrominated diphenyl ethers (PBDEs) are a bioaccumulative, persistent, and toxic class of flame retardants that can potentially impact turtles in natural habitats via exposure through maternal transfer. To simulate maternal transfer in the present study, PBDE congeners BDE-47 and BDE-99 were topically applied to the eggshell and were allowed to diffuse into the egg contents of the red-eared slider (Trachemys scripta elegans) and snapping turtle (Chelydra serpentina). Eggs were topically dosed over 8 d to achieve a target concentration of 40 ng/g in the egg contents. Transfer efficiency was higher for BDE-47 than for BDE-99 in the red-eared sliders (25.8 ± 1.9% vs 9.9 ± 1.1%) and snapping turtles (31.3 ± 1.6% vs 12.5 ± 1.4%), resulting in greater BDE-47 and lower BDE-99 egg content concentrations relative to the 40 ng/g target. However, only 25.8 and 31.3% of the total BDE-47 and 9.9 and 12.5% of the total BDE-99 dose applied could be accounted for in the red-eared slider and snapping turtle egg contents, respectively. Additionally, increased BDE-47 in red-eared slider egg contents dosed with only BDE-99 indicate that BDE-99 might have been debrominated to BDE-47. The efficacy of topical dosing for administering desired embryonic exposures is clearly affected by the chemical properties of the applied compounds and was more successful for BDE-47 in both species. Copyright © 2012 SETAC.

15 CFR 744.1 - General provisions.

Code of Federal Regulations, 2011 CFR

2011-01-01

... against exports, reexports, and selected transfers to certain end-users and end-uses as introduced under... by BIS. Sections 744.2, 744.3, 744.4 prohibit exports, reexports and transfers (in-country) of items.... Section 744.5 prohibits exports, reexports and transfers (in-country) of items subject to the EAR to...

15 CFR 744.1 - General provisions.

Code of Federal Regulations, 2014 CFR

2014-01-01

... against exports, reexports, and selected transfers to certain end-users and end-uses as introduced under... by BIS. Sections 744.2, 744.3, 744.4 prohibit exports, reexports and transfers (in-country) of items.... Section 744.5 prohibits exports, reexports and transfers (in-country) of items subject to the EAR to...

15 CFR 744.1 - General provisions.

Code of Federal Regulations, 2012 CFR

2012-01-01

... against exports, reexports, and selected transfers to certain end-users and end-uses as introduced under... by BIS. Sections 744.2, 744.3, 744.4 prohibit exports, reexports and transfers (in-country) of items.... Section 744.5 prohibits exports, reexports and transfers (in-country) of items subject to the EAR to...

15 CFR 744.1 - General provisions.

Code of Federal Regulations, 2013 CFR

2013-01-01

... against exports, reexports, and selected transfers to certain end-users and end-uses as introduced under... by BIS. Sections 744.2, 744.3, 744.4 prohibit exports, reexports and transfers (in-country) of items.... Section 744.5 prohibits exports, reexports and transfers (in-country) of items subject to the EAR to...

Call sign intelligibility improvement using a spatial auditory display

NASA Technical Reports Server (NTRS)

Begault, Durand R.

1994-01-01

A spatial auditory display was designed for separating the multiple communication channels usually heard over one ear to different virtual auditory positions. The single 19 foot rack mount device utilizes digital filtering algorithms to separate up to four communication channels. The filters use four different binaural transfer functions, synthesized from actual outer ear measurements, to impose localization cues on the incoming sound. Hardware design features include 'fail-safe' operation in the case of power loss, and microphone/headset interfaces to the mobile launch communication system in use at KSC. An experiment designed to verify the intelligibility advantage of the display used 130 different call signs taken from the communications protocol used at NASA KSC. A 6 to 7 dB intelligibility advantage was found when multiple channels were spatially displayed, compared to monaural listening. The findings suggest that the use of a spatial auditory display could enhance both occupational and operational safety and efficiency of NASA operations.

Middle ear osteoma causing progressive facial nerve weakness: a case report.

PubMed

Curtis, Kate; Bance, Manohar; Carter, Michael; Hong, Paul

2014-09-18

Facial nerve weakness is most commonly due to Bell's palsy or cerebrovascular accidents. Rarely, middle ear tumor presents with facial nerve dysfunction. We report a very unusual case of middle ear osteoma in a 49-year-old Caucasian woman causing progressive facial nerve deficit. A subtle middle ear lesion was observed on otoscopy and computed tomographic images demonstrated an osseous middle ear tumor. Complete surgical excision resulted in the partial recovery of facial nerve function. Facial nerve dysfunction is rarely caused by middle ear tumors. The weakness is typically due to a compressive effect on the middle ear portion of the facial nerve. Early recognition is crucial since removal of these lesions may lead to the recuperation of facial nerve function.

Histological study of the external, middle and inner ear of horses.

PubMed

Blanke, A; Aupperle, H; Seeger, J; Kubick, C; Schusser, G F

2015-12-01

Clinical, anatomical and histological aspects of the equine acoustic organ have been poorly investigated and illustrated in literature so far. It is understood that an intact acoustic organ and hearing function are of vital importance for the well-being of flight animals like horses. The knowledge of the acoustic organ is usually transferred analogously from other mammals to horses. The purpose of this study was to provide a detailed and complete histological description of the healthy equine auditory organ, and to determine its congruity to other mammalians. Anatomical dissections and histological preparations were carried out on ten cadaver heads. Specimens of various parts of the equine acoustic organ were taken and evaluated histologically. The histological composition of external, middle and inner ear structures are predominantly congruent to those of other mammals, especially to human beings. Unique inwardly directed rete pegs within the osseous ear canal and the prominent tensor tympani muscle are described for the first time. Results obtained in this study can be employed as references for further research on the equine acoustic organ and improve the understanding of the clinical development of hearing loss, otitis externa/media/interna or tympanosclerosis. © 2014 Blackwell Verlag GmbH.

Investigation of middle ear anatomy and function with combined video otoscopy-phase sensitive OCT

PubMed Central

Park, Jesung; Cheng, Jeffrey T.; Ferguson, Daniel; Maguluri, Gopi; Chang, Ernest W.; Clancy, Caitlin; Lee, Daniel J.; Iftimia, Nicusor

2016-01-01

We report the development of a novel otoscopy probe for assessing middle ear anatomy and function. Video imaging and phase-sensitive optical coherence tomography are combined within the same optical path. A sound stimuli channel is incorporated as well to study middle ear function. Thus, besides visualizing the morphology of the middle ear, the vibration amplitude and frequency of the eardrum and ossicles are retrieved as well. Preliminary testing on cadaveric human temporal bone models has demonstrated the capability of this instrument for retrieving middle ear anatomy with micron scale resolution, as well as the vibration of the tympanic membrane and ossicles with sub-nm resolution. PMID:26977336

Theory of forward and reverse middle-ear transmission applied to otoacoustic emissions in infant and adult ears

PubMed Central

Keefe, Douglas H.; Abdala, Carolina

2008-01-01

The purpose of this study is to understand why otoacoustic emission (OAE) levels are higher in normal-hearing human infants relative to adults. In a previous study, distortion product (DP) OAE input/output (I/O) functions were shown to differ at f2=6 kHz in adults compared to infants through 6 months of age. These DPOAE I/O functions were used to noninvasively assess immaturities in forward/reverse transmission through the ear canal and middle ear [Abdala, C., and Keefe, D. H., (2006). J. Acoust Soc. Am. 120, 3832–3842]. In the present study, ear-canal reflectance and DPOAEs measured in the same ears were analyzed using a scattering-matrix model of forward and reverse transmission in the ear canal, middle ear, and cochlea. Reflectance measurements were sensitive to frequency-dependent effects of ear-canal and middle-ear transmission that differed across OAE type and subject age. Results indicated that DPOAE levels were larger in infants mainly because the reverse middle-ear transmittance level varied with ear-canal area, which differed by more than a factor of 7 between term infants and adults. The forward middle-ear transmittance level was −16 dB less in infants, so that the conductive efficiency was poorer in infants than adults. PMID:17348521

Can you hear me now? Understanding vertebrate middle ear development

PubMed Central

Chapman, Susan Caroline

2010-01-01

The middle ear is a composite organ formed from all three germ layers and the neural crest. It provides the link between the outside world and the inner ear, where sound is transduced and routed to the brain for processing. Extensive classical and modern studies have described the complex morphology and origin of the middle ear. Non-mammalian vertebrates have a single ossicle, the columella. Mammals have three functionally equivalent ossicles, designated the malleus, incus and stapes. In this review, I focus on the role of genes known to function in the middle ear. Genetic studies are beginning to unravel the induction and patterning of the multiple middle ear elements including the tympanum, skeletal elements, the air-filled cavity, and the insertion point into the inner ear oval window. Future studies that elucidate the integrated spatio-temporal signaling mechanisms required to pattern the middle ear organ system are needed. The longer-term translational benefits of understanding normal and abnormal ear development will have a direct impact on human health outcomes. PMID:21196256

Transfer function for vital infrasound pressures between the carotid artery and the tympanic membrane.

PubMed

Furihata, Kenji; Yamashita, Masato

2013-02-01

While occupational injury is associated with numerous individual and work-related risk factors, including long working hours and short sleep duration, the complex mechanisms causing such injuries are not yet fully understood. The relationship between the infrasound pressures of the tympanic membrane [ear canal pressure (ECP)], detected using an earplug embedded with a low-frequency microphone, and the carotid artery [carotid artery pressure (CAP)], detected using a stethoscope fitted with the same microphone, can be quantitatively characterized using systems analysis. The transfer functions of 40 normal workers (19 to 57 years old) were characterized, involving the analysis of 446 data points. The ECP waveform exhibits a pulsatile character with a slow respiratory component, which is superimposed on a biphasic recording that is synchronous with the cardiac cycle. The respiratory ECP waveform correlates with the instantaneous heart rate. The results also revealed that various fatigue-related risk factors may affect the mean magnitudes of the measured pressures and the delay transfer functions between CAP and ECP in the study population; these factors include systolic blood pressure, salivary amylase activity, age, sleep duration, postural changes, chronic fatigue, and pulse rate.

[Investigation of neural stem cell-derived donor contribution in the inner ear following blastocyst injection].

PubMed

Volkenstein, S; Brors, D; Hansen, S; Mlynski, R; Dinger, T C; Müller, A M; Dazert, S

2008-03-01

Utilising the enormous proliferation and multi-lineage differentiation potentials of somatic stem cells represents a possible therapeutical strategy for diseases of non-regenerative tissues like the inner ear. In the current study, the possibility of murine neural stem cells to contribute to the developing inner ear following blastocyst injection was investigated. Fetal brain-derived neural stem cells from the embryonic day 14 cortex of male mice were isolated and expanded for four weeks in neurobasal media supplemented with bFGF and EGF. Neural stem cells of male animals were harvested, injected into blastocysts and the blastocysts were transferred into pseudo-pregnant foster animals. Each blastocyst was injected with 5-15 microspheres growing from single cell suspension from neurospheres dissociated the day before. The resulting mice were investigated six months POST PARTUM for the presence of donor cells. Brainstem evoked response audiometry (BERA) was performed in six animals. To visualize donor cells Lac-Z staining was performed on sliced cochleas of two animals. In addition, the cochleas of four female animals were isolated and genomic DNA of the entire cochlea was analyzed for donor contribution by Y-chromosome-specific PCR. All animals had normal thresholds in brainstem evoked response audiometry. The male-specific PCR product indicating the presence of male donor cells were detected in the cochleas of three of the four female animals investigated. In two animals, male donor cells were detected unilateral, in one animal bilateral. The results suggest that descendants of neural stem cells are detectable in the inner ear after injection into blastocysts and possess the ability to integrate into the developing inner ear without obvious loss in hearing function.

15 CFR 744.11 - License requirements that apply to entities acting contrary to the national security or foreign...

Code of Federal Regulations, 2013 CFR

2013-01-01

..., reexport, or transfer (in-country) any item subject to the EAR to an entity that is listed on the Entity... reexports to that party of items that are subject to the EAR are prohibited by or require a license from... United States. (1) Supporting persons engaged in acts of terror. (2) Actions that could enhance the...

Surgical and Technical Modalities for Hearing Restoration in Ear Malformations.

PubMed

Dazert, Stefan; Thomas, Jan Peter; Volkenstein, Stefan

2015-12-01

Malformations of the external and middle ear often go along with an aesthetic and functional handicap. Independent of additional aesthetic procedures, a successful functional hearing restoration leads to a tremendous gain in quality of life for affected patients. The introduction of implantable hearing systems (bone conduction and middle ear devices) offers new therapeutic options in this field. We focus on functional rehabilitation of patients with malformations, either by surgical reconstruction or the use of different implantable hearing devices, depending on the disease itself and the severity of malformation as well as hearing impairment. Patients with an open ear canal and minor malformations are good candidates for surgical hearing restoration of middle ear structures with passive titanium or autologous implants. In cases with complete fibrous or bony atresia of the ear canal, the most promising functional outcome and gain in quality of life can be expected with an active middle ear implant or a bone conduction device combined with a surgical aesthetic rehabilitation in a single or multi-step procedure. Although the surgical procedure for bone conduction devices is straightforward and safe, more sophisticated operations for active middle ear implants (e.g., Vibrant Soundbridge, MED-EL, Innsbruck, Austria) provide an improved speech discrimination in noise and the ability of sound localization compared with bone conduction devices where the stimulation reaches both cochleae. Thieme Medical Publishers 333 Seventh Avenue, New York, NY 10001, USA.

Measurement of mucociliary function of the eustachian tube

DOE Office of Scientific and Technical Information (OSTI.GOV)

Nuutinen, J.; Kaerjae, J.; Karjalainen, P.

1983-10-01

Mucociliary function of the eustachian tube was measured with a radioisotopic method; 0.01 mL of a human serum albumin labeled with technetium 99m was instilled into the anterior part of the middle ear cavity either through a perforation or by puncturing the tympanic membrane, and its course was followed by a gamma-camera. In the normal eustachian tube, the velocity of the mucociliary transport was 0.7 to 1.1 mm/min. The mucociliary function was totally absent in chronic otitis media, in untreated secretory otitis media, and in the ear with a moist perforation of the tympanic membrane. The mucociliary transport returned tomore » normal when the ear was clinically healed. It is assumed that the impairment of the mucociliary function of the eustachian tube and middle ear plays an important role in the pathogenesis of secretory otitis media and chronic ear discharge.« less

Of mice, moles and guinea pigs: functional morphology of the middle ear in living mammals.

PubMed

Mason, Matthew J

2013-07-01

The middle ear apparatus varies considerably among living mammals. Body size, phylogeny and acoustic environment all play roles in shaping ear structure and function, but experimental studies aimed ultimately at improving our understanding of human hearing can sometimes overlook these important species differences. This review focuses on three groups of mammals, bringing together anatomical, zoological and physiological information in order to highlight unusual features of their middle ears and attempt to interpret their function. "Microtype" ears, found in species such as mice and bats, are associated with high-frequency hearing. The orbicular apophysis, the focus of some recent developmental studies on mouse ears, is characteristic of microtype mallei but is not found in humans or other "freely mobile" species. The apophysis increases ossicular inertia about the anatomical axis of rotation: its adaptive purpose in a high-frequency ear is still not clear. Subterranean mammals have convergently evolved a "freely mobile" ossicular morphology which appears to favour lower-frequency sound transmission. More unusual features found in some of these animals include acoustically coupled middle ear cavities, the loss of middle ear muscles and hypertrophied ossicles which are believed to subserve a form of inertial bone conduction. Middle ears of the rodent group Ctenohystrica (which includes guinea pigs and chinchillas, important models in hearing research) show some striking characteristics which together comprise a unique type of auditory apparatus requiring a classification of its own, referred to here as the "Ctenohystrica type". These characteristics include a distinctive malleus morphology, fusion of the malleus and incus, reduction or loss of the stapedius muscle, a synovial stapedio-vestibular articulation and, in chinchillas, enormously expanded middle ear cavities. These characteristics may be functionally linked and associated with the excellent low-frequency hearing found in these animals. The application of new experimental and imaging data into increasingly sophisticated models continues to improve our understanding of middle ear function. However, a more rigorous comparative approach and a better appreciation of the complex patterns of convergent and divergent evolution reflected in the middle ear structures of living mammals are also needed, in order to put findings from different species into the appropriate context. This article is part of a special issue entitled "MEMRO 2012". Copyright © 2012 Elsevier B.V. All rights reserved.

Nonlinear aspects of infrasonic pressure transfer into the perilymph.

PubMed

Krukowski, B; Carlborg, B; Densert, O

1980-06-01

The perilymphatic pressure was studied in response to various low frequency pressure changes in the ear canal. The pressure transfer was analysed and found to be nonlinear in many aspects. The pressure response was found to contain two time constants representing the inner ear pressure regulating mechanisms. The time constants showed an asymmetry in response to positive and negative going inputs--the effects to some extent proportional to input levels. Further nonlinearities were found when infrasonic sine waves were applied to the ear. Harmonic distortion and modulation appeared. When short bursts of infrasound were introduced a clear d.c. shift was observed as a consequence of an asymmetry in the response to positive and negative going pressure inputs. A temporary change in mean perilymphatic pressure was thus achieved and continued throughout the duration of the signal. At very low frequencies a distinct phase shift was detected in the sine waves. This appeared as a phase lead, breaking the continuity of the output sine wave.

Biocompatibility of Liposome Nanocarriers in the Rat Inner Ear After Intratympanic Administration

NASA Astrophysics Data System (ADS)

Zou, Jing; Feng, Hao; Sood, Rohit; Kinnunen, Paavo K. J.; Pyykko, Ilmari

2017-05-01

Liposome nanocarriers (LPNs) are potentially the future of inner ear therapy due to their high drug loading capacity and efficient uptake in the inner ear after a minimally invasive intratympanic administration. However, information on the biocompatibility of LPNs in the inner ear is lacking. The aim of the present study is to document the biocompatibility of LPNs in the inner ear after intratympanic delivery. LPNs with or without gadolinium-tetra-azacyclo-dodecane-tetra-acetic acid (Gd-DOTA) were delivered to the rats through transtympanic injection. The distribution of the Gd-DOTA-containing LPNs in the middle and inner ear was tracked in vivo using MRI. The function of the middle and inner ear barriers was evaluated using gadolinium-enhanced MRI. The auditory function was measured using auditory brainstem response (ABR). The potential inflammatory response was investigated by analyzing glycosaminoglycan and hyaluronic acid secretion and CD44 and TLR2 expression in the inner ear. The potential apoptosis was analyzed using terminal transferase (TdT) to label the free 3'OH breaks in the DNA strands of apoptotic cells with TMR-dUTP (TUNEL staining). As a result, LPNs entered the inner ear efficiently after transtympanic injection. The transtympanic injection of LPNs with or without Gd-DOTA neither disrupted the function of the middle and inner ear barriers nor caused hearing impairment in rats. The critical inflammatory biological markers in the inner ear, including glycosaminoglycan and hyaluronic acid secretion and CD44 and TLR2 expression, were not influenced by the administration of LPNs. There was no significant cell death associated with the administration of LPNs. The transtympanic injection of LPNs is safe for the inner ear, and LPNs may be applied as a drug delivery matrix in the clinical therapy of sensorineural hearing loss.

Early uneven ear input induces long-lasting differences in left-right motor function.

PubMed

Antoine, Michelle W; Zhu, Xiaoxia; Dieterich, Marianne; Brandt, Thomas; Vijayakumar, Sarath; McKeehan, Nicholas; Arezzo, Joseph C; Zukin, R Suzanne; Borkholder, David A; Jones, Sherri M; Frisina, Robert D; Hébert, Jean M

2018-03-01

How asymmetries in motor behavior become established normally or atypically in mammals remains unclear. An established model for motor asymmetry that is conserved across mammals can be obtained by experimentally inducing asymmetric striatal dopamine activity. However, the factors that can cause motor asymmetries in the absence of experimental manipulations to the brain remain unknown. Here, we show that mice with inner ear dysfunction display a robust left or right rotational preference, and this motor preference reflects an atypical asymmetry in cortico-striatal neurotransmission. By unilaterally targeting striatal activity with an antagonist of extracellular signal-regulated kinase (ERK), a downstream integrator of striatal neurotransmitter signaling, we can reverse or exaggerate rotational preference in these mice. By surgically biasing vestibular failure to one ear, we can dictate the direction of motor preference, illustrating the influence of uneven vestibular failure in establishing the outward asymmetries in motor preference. The inner ear-induced striatal asymmetries identified here intersect with non-ear-induced asymmetries previously linked to lateralized motor behavior across species and suggest that aspects of left-right brain function in mammals can be ontogenetically influenced by inner ear input. Consistent with inner ear input contributing to motor asymmetry, we also show that, in humans with normal ear function, the motor-dominant hemisphere, measured as handedness, is ipsilateral to the ear with weaker vestibular input.

3D printed bionic ears.

PubMed

Mannoor, Manu S; Jiang, Ziwen; James, Teena; Kong, Yong Lin; Malatesta, Karen A; Soboyejo, Winston O; Verma, Naveen; Gracias, David H; McAlpine, Michael C

2013-06-12

The ability to three-dimensionally interweave biological tissue with functional electronics could enable the creation of bionic organs possessing enhanced functionalities over their human counterparts. Conventional electronic devices are inherently two-dimensional, preventing seamless multidimensional integration with synthetic biology, as the processes and materials are very different. Here, we present a novel strategy for overcoming these difficulties via additive manufacturing of biological cells with structural and nanoparticle derived electronic elements. As a proof of concept, we generated a bionic ear via 3D printing of a cell-seeded hydrogel matrix in the anatomic geometry of a human ear, along with an intertwined conducting polymer consisting of infused silver nanoparticles. This allowed for in vitro culturing of cartilage tissue around an inductive coil antenna in the ear, which subsequently enables readout of inductively-coupled signals from cochlea-shaped electrodes. The printed ear exhibits enhanced auditory sensing for radio frequency reception, and complementary left and right ears can listen to stereo audio music. Overall, our approach suggests a means to intricately merge biologic and nanoelectronic functionalities via 3D printing.

Combined Effect of Fluid and Pressure on Middle Ear Function

PubMed Central

Dai, Chenkai; Wood, Mark W.; Gan, Rong Z.

2008-01-01

In our previous studies, the effects of effusion and pressure on sound transmission were investigated separately. The aim of this study is to investigate the combined effect of fluid and pressure on middle ear function. An otitis media with effusion model was created by injecting saline solution and air pressure simultaneously into the middle ear of human temporal bones. Tympanic membrane displacement in response to 90 dB SPL sound input was measured by a laser vibrometer and the compliance of the middle ear was measured by a tympanometer. The movement of the tympanic membrane at the umbo was reduced up to 17 dB by the combination of fluid and pressure in the middle ear over the auditory frequency range. The fluid and pressure effects on the umbo movement in the fluid-pressure combination are not additive. The combined effect of fluid and pressure on the umbo movement is different compared with that of only fluid or pressure change in the middle ear. Negative pressure in fluid-pressure combination had more effect on middle ear function than positive pressure. Tympanometry can detect the middle ear pressure of the fluid-pressure combination. This study provides quantitative information for analysis of the combined effect of fluid and pressure on tympanic membrane movement. PMID:18162348

Effects of obstructive sleep apnea surgery on middle ear function.

PubMed

Lin, Hsin-Ching; Friedman, Michael; Chang, Hsueh-Wen; Shao, Chi-Hsin; Pulver, Tanya M; Chen, Yung-Che

2011-04-01

To study the effect of Z-palatopharyngoplasty plus radiofrequency of the base of the tongue on middle ear function. A retrospective review of a prospective data set at a tertiary care center. University-affiliated medical center. The study population included 47 patients (42 men and 5 women; mean age, 40.8 years) who underwent Z-palatopharyngoplasty plus radiofrequency of the base of the tongue for obstructive sleep apnea/hypopnea syndrome. All patients had healthy eardrums and no previous history of chronic ear disease. Pure-tone audiometric and tympanometric assessments were performed preoperatively and at 3 days, 7 days, 1 month, and 3 months postoperatively. Levels of baseline and postoperative middle ear pressure were compared. Twelve patients (26%) reported otologic concerns, such as ear pressure and/or otalgia, within 1 week postoperatively. No permanent otologic discomfort occurred. A trend toward reduced middle ear pressure was noted in this study. The decrease in middle ear pressure became apparent on day 3. However, mean pressure changes were no longer significantly different than preoperative values by 1 week after surgery. We found that Z-palatopharyngoplasty plus radiofrequency of the base of the tongue for obstructive sleep apnea/hypopnea syndrome induces changes in middle ear function. However, the changes were temporary and not significant after 3 months of follow-up.

Basilar-membrane interference patterns from multiple internal reflection of cochlear traveling waves.

PubMed

Shera, Christopher A; Cooper, Nigel P

2013-04-01

At low stimulus levels, basilar-membrane (BM) mechanical transfer functions in sensitive cochleae manifest a quasiperiodic rippling pattern in both amplitude and phase. Analysis of the responses of active cochlear models suggests that the rippling is a mechanical interference pattern created by multiple internal reflection within the cochlea. In models, the interference arises when reverse-traveling waves responsible for stimulus-frequency otoacoustic emissions (SFOAEs) reflect off the stapes on their way to the ear canal, launching a secondary forward-traveling wave that combines with the primary wave produced by the stimulus. Frequency-dependent phase differences between the two waves then create the rippling pattern measurable on the BM. Measurements of BM ripples and SFOAEs in individual chinchilla ears demonstrate that the ripples are strongly correlated with the acoustic interference pattern measured in ear-canal pressure, consistent with a common origin involving the generation of SFOAEs. In BM responses to clicks, the ripples appear as temporal fine structure in the response envelope (multiple lobes, waxing and waning). Analysis of the ripple spacing and response phase gradients provides a test for the role of fast- and slow-wave modes of reverse energy propagation within the cochlea. The data indicate that SFOAE delays are consistent with reverse slow-wave propagation but much too long to be explained by fast waves.

Voltage and frequency dependence of prestin-associated charge transfer

PubMed Central

Sun, Sean X.; Farrell, Brenda; Chana, Matthew S.; Oster, George; Brownell, William E.; Spector, Alexander A.

2009-01-01

Membrane protein prestin is a critical component of the motor complex that generates forces and dimensional changes in cells in response to changes in the cell membrane potential. In its native cochlear outer hair cell, prestin is crucial to the amplification and frequency selectivity of the mammalian ear up to frequencies of tens of kHz. Other cells transfected with prestin acquire voltage-dependent properties similar to those of the native cell. The protein performance is critically dependent on chloride ions, and intrinsic protein charges also play a role. We propose an electro-diffusion model to reveal the frequency and voltage dependence of electric charge transfer by prestin. The movement of the combined charge (i.e., anion and protein charges) across the membrane is described with a Fokker-Planck equation coupled to a kinetic equation that describes the binding of chloride ions to prestin. We found a voltage-and frequency-dependent phase shift between the transferred charge and the applied electric field that determines capacitive and resistive components of the transferred charge. The phase shift monotonically decreases from zero to -90 degree as a function of frequency. The capacitive component as a function of voltage is bell-shaped, and decreases with frequency. The resistive component is bell-shaped for both voltage and frequency. The capacitive and resistive components are similar to experimental measurements of charge transfer at high frequencies. The revealed nature of the transferred charge can help reconcile the high-frequency electrical and mechanical observations associated with prestin, and it is important for further analysis of the structure and function of this protein. PMID:19490917

The Sound Broadcasting System of the Bullfrog

NASA Astrophysics Data System (ADS)

Purgue, Alejandro P.

1995-01-01

This work presents a comparison across selected species of several aspects of the mechanism of sound broadcasting in anuran amphibians. These studies indicate that all anuran species studied to date broadcast their calls through structures that resonate at the dominant frequency in their calls. Measurements of the magnitude of the transfer function of the radiating structures show that the structures responsible for radiating the bulk of the energy present in the call vary depending on the species considered. Bullfrogs (Rana catesbeiana) radiate most of the energy (89% sound level) present in their calls through their eardrums. In this species the transfer function of the eardrum displays several peaks coincident in frequency and amplitude with the energy distribution observed in the mating and release call of the species. The vocal sac and gular area contribute energy only in the lower band (150 to 400 Hz) of the call. The ears are responsible for radiating additional frequency bands to the ones being radiated through the gular area and vocal sacs. This condition appears to be derived. In Rana pipiens the ears also broadcast a significant portion of the energy present in the call (63% sound level) but the frequencies of the aural emissions are a subset of those frequencies radiated through the vocal sac and gular area. Character optimization suggests that this is the primitive condition for ranid frogs. Finally, the barking treefrog (Hyla gratiosa) appears to use two different structures to radiate different portions of the call. The low frequency band appears to be preferentially radiated through the lungs while the high frequency components of the call are radiated through the vocal sac.

Effect of the Yield Stress and r-value Distribution on the Earing Profile of Cup Drawing with Yld2000-2d Yield Function

NASA Astrophysics Data System (ADS)

Lou, Yanshan; Bae, Gihyun; Lee, Changsoo; Huh, Hoon

2010-06-01

This paper deals with the effect of the yield stress and r-value distribution on the earing in the cup drawing. The anisotropic yield function, Yld2000-2d yield function, is selected to describe the anisotropy of two metal sheets, 719B and AA5182-O. The tool dimension is referred from the Benchmark problem of NUMISHEET'2002. The Downhill Simplex method is applied to identify the anisotropic coefficients in Yld2000-2d yield function. Simulations of the drawing process are performed to investigate the earing profile of two materials. The earing profiles obtained from simulations are compared with the analytical model developed by Hosford and Caddell. Simulations are conducted with respect to the change of the yield stress and r-value distribution, respectively. The correlation between the anisotropy and the earing tendency is investigated based on simulation data. Finally, the earing mechanism is analyzed through the deformation process of the blank during the cup deep drawing. It can be concluded that ears locate at angular positions with lower yield stress and higher r-value while the valleys appear at the angular position with higher yield stress and lower r-value. The effect of the yield stress distribution is more important for the cup height distribution than that of the r-value distribution.

Generation of inner ear organoids containing functional hair cells from human pluripotent stem cells.

PubMed

Koehler, Karl R; Nie, Jing; Longworth-Mills, Emma; Liu, Xiao-Ping; Lee, Jiyoon; Holt, Jeffrey R; Hashino, Eri

2017-06-01

The derivation of human inner ear tissue from pluripotent stem cells would enable in vitro screening of drug candidates for the treatment of hearing and balance dysfunction and may provide a source of cells for cell-based therapies of the inner ear. Here we report a method for differentiating human pluripotent stem cells to inner ear organoids that harbor functional hair cells. Using a three-dimensional culture system, we modulate TGF, BMP, FGF, and WNT signaling to generate multiple otic-vesicle-like structures from a single stem-cell aggregate. Over 2 months, the vesicles develop into inner ear organoids with sensory epithelia that are innervated by sensory neurons. Additionally, using CRISPR-Cas9, we generate an ATOH1-2A-eGFP cell line to detect hair cell induction and demonstrate that derived hair cells exhibit electrophysiological properties similar to those of native sensory hair cells. Our culture system should facilitate the study of human inner ear development and research on therapies for diseases of the inner ear.

Cochlear Implant Electrode Effect on Sound Energy Transfer within the Cochlea during Acoustic Stimulation

PubMed Central

Greene, Nathaniel T.; Mattingly, Jameson K.; Jenkins, Herman A.; Tollin, Daniel J.; Easter, James R.; Cass, Stephen P.

2015-01-01

Hypothesis Cochlear implants (CI) designed for hearing preservation will not alter mechanical properties of the middle and inner ear as measured by intracochlear pressure (PIC) and stapes velocity (Vstap). Background CIs designed to provide combined electrical and acoustic stimulation (EAS) are now available. To maintain functional acoustic hearing, it is important to know if a CI electrode can alter middle or inner ear mechanics, as any alteration could contribute to elevated low-frequency thresholds in EAS patients. Methods Seven human cadaveric temporal bones were prepared, and pure-tone stimuli from 120Hz–10kHz were presented at a range of intensities up to 110 dB SPL. PIC in the scala vestibuli (PSV) and tympani (PST) were measured with fiber-optic pressure sensors concurrently with VStap using laser Doppler vibrometry. Five CI electrodes from two different manufacturers, with varying dimensions were inserted via a round window approach at six different depths (16–25 mm). Results The responses of PIC and VStap to acoustic stimulation were assessed as a function of stimulus frequency, normalized to SPL in the external auditory canal (EAC), in baseline and electrode inserted conditions. Responses measured with electrodes inserted were generally within ~5 dB of baseline, indicating little effect of cochlear implant electrode insertion on PIC and VStap. Overall, mean differences across conditions were small for all responses, and no substantial differences were consistently visible across electrode types. Conclusions Results suggest that the influence of a CI electrode on middle and inner ear mechanics is minimal, despite variation in electrode lengths and configurations. PMID:26333018

Estimation of outer-middle ear transmission using DPOAEs and fractional-order modeling of human middle ear

NASA Astrophysics Data System (ADS)

Naghibolhosseini, Maryam

Our ability to hear depends primarily on sound waves traveling through the outer and middle ear toward the inner ear. Hence, the characteristics of the outer and middle ear affect sound transmission to/from the inner ear. The role of the middle and outer ear in sound transmission is particularly important for otoacoustic emissions (OAEs), which are sound signals generated in a healthy cochlea, and recorded by a sensitive microphone placed in the ear canal. OAEs are used to evaluate the health and function of the cochlea; however, they are also affected by outer and middle ear characteristics. To better assess cochlear health using OAEs, it is critical to quantify the impact of the outer and middle ear on sound transmission. The reported research introduces a noninvasive approach to estimate outer-middle ear transmission using distortion product otoacoustic emissions (DPOAEs). In addition, the role of the outer and middle ear on sound transmission was investigated by developing a physical/mathematical model, which employed fractional-order lumped elements to include the viscoelastic characteristics of biological tissues. Impedance estimations from wideband refectance measurements were used for parameter fitting of the model. The model was validated comparing its estimates of the outer-middle ear sound transmission with those given by DPOAEs. The outer-middle ear transmission by the model was defined as the sum of forward and reverse outer-middle ear transmissions. To estimate the reverse transmission by the model, the probe-microphone impedance was calculated through estimating the Thevenin-equivalent circuit of the probe-microphone. The Thevenin-equivalent circuit was calculated using measurements in a number of test cavities. Such modeling enhances our understanding of the roles of different parts of the outer and middle ear and how they work together to determine their function. In addition, the model would be potentially helpful in diagnosing pathologies of cochlear or middle ear origin.

3D Printed Bionic Ears

PubMed Central

Mannoor, Manu S.; Jiang, Ziwen; James, Teena; Kong, Yong Lin; Malatesta, Karen A.; Soboyejo, Winston O.; Verma, Naveen; Gracias, David H.; McAlpine, Michael C.

2013-01-01

The ability to three-dimensionally interweave biological tissue with functional electronics could enable the creation of bionic organs possessing enhanced functionalities over their human counterparts. Conventional electronic devices are inherently two-dimensional, preventing seamless multidimensional integration with synthetic biology, as the processes and materials are very different. Here, we present a novel strategy for overcoming these difficulties via additive manufacturing of biological cells with structural and nanoparticle derived electronic elements. As a proof of concept, we generated a bionic ear via 3D printing of a cell-seeded hydrogel matrix in the precise anatomic geometry of a human ear, along with an intertwined conducting polymer consisting of infused silver nanoparticles. This allowed for in vitro culturing of cartilage tissue around an inductive coil antenna in the ear, which subsequently enables readout of inductively-coupled signals from cochlea-shaped electrodes. The printed ear exhibits enhanced auditory sensing for radio frequency reception, and complementary left and right ears can listen to stereo audio music. Overall, our approach suggests a means to intricately merge biologic and nanoelectronic functionalities via 3D printing. PMID:23635097

Reduced order modeling of head related transfer functions for virtual acoustic displays

NASA Astrophysics Data System (ADS)

Willhite, Joel A.; Frampton, Kenneth D.; Grantham, D. Wesley

2003-04-01

The purpose of this work is to improve the computational efficiency in acoustic virtual applications by creating and testing reduced order models of the head related transfer functions used in localizing sound sources. State space models of varying order were generated from zero-elevation Head Related Impulse Responses (HRIRs) using Kungs Single Value Decomposition (SVD) technique. The inputs to the models are the desired azimuths of the virtual sound sources (from minus 90 deg to plus 90 deg, in 10 deg increments) and the outputs are the left and right ear impulse responses. Trials were conducted in an anechoic chamber in which subjects were exposed to real sounds that were emitted by individual speakers across a numbered speaker array, phantom sources generated from the original HRIRs, and phantom sound sources generated with the different reduced order state space models. The error in the perceived direction of the phantom sources generated from the reduced order models was compared to errors in localization using the original HRIRs.

[The effect of OSAHS on middle ear and inner ear vestibule function advances].

PubMed

Li, K L; Li, J R

2016-05-20

Obstructive sleep apnea hypopnea syndrome(OSAHS) as a common frequentlyoccurring disease, it can cause repeated episodes of hypoxaemia and hypercapnia during sleep. With long period of hypoxaemia, obvious pathological changes and dysfunction emerged in heart，brain and lung then all kinds of clinical symptoms appear. Because of the middle ear and inner ear themselves anatomical characteristics and blood supply of regulating mechanism， they often has been damaged before the other important organ damage. As scholars have indepth study of the auditory system complications in patients with OSAHS, various influence of OSAHS on the middle ear，inner ear also gradually be known.This paper will review the effect of OSAHS on middle ear， inner ear and vestibule function, hope to have some application value for clinical work. Copyright© by the Editorial Department of Journal of Clinical Otorhinolaryngology Head and Neck Surgery.

Assessment of Eustachian tube function in patients with tympanic membrane retraction and in normal subjects.

PubMed

Canali, Inesângela; Petersen Schmidt Rosito, Letícia; Siliprandi, Bruno; Giugno, Cláudia; Selaimen da Costa, Sady

The diagnosis of Eustachian tube dysfunctions is essential for better understanding of the pathogenesis of chronic otitis media. A series of tests to assess tube function are described in the literature; however, they are methodologically heterogeneous, with differences ranging from application protocols to standardization of tests and their results. To evaluate the variation in middle ear pressure in patients with tympanic membrane retraction and in normal patients during tube function tests, as well as to evaluate intra-individual variation between these tests. An observational, contemporary, cross-sectional study was conducted, in which the factor under study was the variation in middle ear pressure during tube function tests (Valsalva maneuver, sniff test, Toynbee maneuver) in healthy patients and in patients with mild and moderate/severe tympanic retraction. A total of 38 patients (76 ears) were included in the study. Patients underwent tube function tests at two different time points to determine pressure measurements after each maneuver. Statistical analysis was performed using SPSS software, version 18.0, considering p-values <0.05 as statistically significant. Mean (standard deviation) age was 11 (2.72) years; 55.3% of patients were male and 44.7% female. The prevalence of type A tympanogram was higher among participants with healthy ears and those with mild retraction, whereas type C tympanograms were more frequent in the moderate/severe retraction group. An increase in middle ear pressure was observed during the Valsalva maneuver at the first time point evaluated in all three groups of ears (p=0.012). The variation in pressure was not significant either for the sniff test or for the Toynbee maneuver at the two time points evaluated (p≥0.05). Agreement between measurements obtained at the two different time points was weak to moderate for all tests in all three groups of ears, and the variations in discrepancy between measurements were higher in ears with moderate/severe tympanic retraction. In this study population, the mean pressure in the middle ear showed significant variation only during the Valsalva maneuver at the first time point evaluated in the three groups of ears. Normal ears and those with mild retraction behaved similarly in all tests. The tested maneuvers exhibited weak to moderate intra-individual variation, with the greatest variation occurring in ears with moderate/severe retraction. Copyright © 2016 Associação Brasileira de Otorrinolaringologia e Cirurgia Cérvico-Facial. Published by Elsevier Editora Ltda. All rights reserved.

Revisiting gender, race, and ear differences in peripheral auditory function

NASA Astrophysics Data System (ADS)

Boothalingam, Sriram; Klyn, Niall A. M.; Stiepan, Samantha M.; Wilson, Uzma S.; Lee, Jungwha; Siegel, Jonathan H.; Dhar, Sumitrajit

2018-05-01

Various measures of auditory function are reported to be superior in females as compared to males, in African American compared to Caucasian individuals, and in right compared to left ears. We re-examined the influence of these subject variables on hearing thresholds and otoacoustic emissions (OAEs) in a sample of 887 human participants between 10 and 68 years of age. Even though the variables of interest here have been examined before, previous attempts have largely been limited to frequencies up to 8 kHz. We used state-of-the-art signal delivery and recording techniques that compensated for individual differences in ear canal acoustics, allowing us to measure hearing thresholds and OAEs up to 20 kHz. The use of these modern calibration and recording techniques provided the motivation for re-examining these commonly studied variables. While controlling for age, noise exposure history, and general health history, we attempted to isolate the effects of gender, race, and ear (left versus right) on hearing thresholds and OAEs. Our results challenge the notion of a right ear advantage and question the existence of a significant gender and race differences in both hearing thresholds and OAE levels. These results suggest that ear canal anatomy and acoustics should be important considerations when evaluating the influence of gender, race, and ear on peripheral auditory function.

Sound pressure gain produced by the human middle ear.

PubMed

Kurokawa, H; Goode, R L

1995-10-01

The acoustic function of the middle ear is to match sound passing from the low impedance of air to the high impedance of cochlear fluid. Little information is available on the actual middle ear pressure gain in human beings. This article describes experiments on middle ear pressure gain in six fresh human temporal bones. Stapes footplate displacement and phase were measured with a laser Doppler vibrometer before and after removal of the tympanic membrane, malleus, and incus. Acoustic insulation of the round window with clay was performed. Umbo displacement was also measured before tympanic membrane removal to assess baseline tympanic membrane function. The middle ear has its major gain in the lower frequencies, with a peak near 0.9 kHz. The mean gain was 23.0 dB below 1.0 kHz, the resonant frequency of the middle ear; the mean peak gain was 26.6 dB. Above 1.0 kHz, the second pressure gain decreased at a rate of -8.6 dB/octave, with a mean gain of 6.5 dB at 4.0 kHz. Only a small amount of gain was present above 7.0 kHz. Significant individual differences in pressure gain were found between ears that appeared related to variations in tympanic membrane function and not to variations in cochlear impedance.

Better late than never: effective air-borne hearing of toads delayed by late maturation of the tympanic middle ear structures.

PubMed

Womack, Molly C; Christensen-Dalsgaard, Jakob; Hoke, Kim L

2016-10-15

Most vertebrates have evolved a tympanic middle ear that enables effective hearing of airborne sound on land. Although inner ears develop during the tadpole stages of toads, tympanic middle ear structures are not complete until months after metamorphosis, potentially limiting the sensitivity of post-metamorphic juveniles to sounds in their environment. We tested the hearing of five species of toads to determine how delayed ear development impairs airborne auditory sensitivity. We performed auditory brainstem recordings to test the hearing of the toads and used micro-computed tomography and histology to relate the development of ear structures to hearing ability. We found a large (14-27 dB) increase in hearing sensitivity from 900 to 2500 Hz over the course of ear development. Thickening of the tympanic annulus cartilage and full ossification of the middle ear bone are associated with increased hearing ability in the final stages of ear maturation. Thus, juvenile toads are at a hearing disadvantage, at least in the high-frequency range, throughout much of their development, because late-forming ear elements are critical to middle ear function at these frequencies. We discuss the potential fitness consequences of late hearing development, although research directly addressing selective pressures on hearing sensitivity across ontogeny is lacking. Given that most vertebrate sensory systems function very early in life, toad tympanic hearing may be a sensory development anomaly. © 2016. Published by The Company of Biologists Ltd.

Treatment of peripheral vestibular dysfunction using photobiomodulation

NASA Astrophysics Data System (ADS)

Lee, Min Young; Hyun, Jai-Hwan; Suh, Myung-Whan; Ahn, Jin-Chul; Chung, Phil-Sang; Jung, Jae Yun; Rhee, Chung Ku

2017-08-01

Gentamicin, which is still used in modern medicine, is a known vestibular toxic agent, and various degrees of balance problems have been observed after exposure to this pharmacologic agent. Photobiomodulation is a candidate therapy for vertigo due to its ability to reach deep inner ear organs such as the cochlea. Previous reports have suggested that photobiomodulation can improve hearing and cochlea function. However, few studies have examined the effect of photobiomodulation on balance dysfunction. We used a rat model to mimic human vestibulopathy resulting from gentamicin treatment and evaluated the effect of photobiomodulation on vestibular toxicity. Slow harmonic acceleration (SHA) rotating platform testing was used for functional evaluation and both qualitative and quantitative epifluorescence analyses of cupula histopathology were performed. Animals were divided into gentamicin only and gentamicin plus laser treatment groups. Laser treatment was applied to one ear, and function and histopathology were evaluated in both ears. Decreased function was observed in both ears after gentamicin treatment, demonstrated by low gain and no SHA asymmetry. Laser treatment minimized the damage resulting from gentamicin treatment as shown by SHA asymmetry and recovered gain in the treated ear. Histology results reflected the functional results, showing increased hair cell density and epifluorescence intensity in laser-treated cupulae.

Inner ear manifestations in CHARGE: Abnormalities, treatments, animal models, and progress toward treatments in auditory and vestibular structures.

PubMed

Choo, Daniel I; Tawfik, Kareem O; Martin, Donna M; Raphael, Yehoash

2017-12-01

The inner ear contains the sensory organs for hearing and balance. Both hearing and balance are commonly affected in individuals with CHARGE syndrome (CS), an autosomal dominant condition caused by heterozygous pathogenic variants in the CHD7 gene. Semicircular canal dysplasia or aplasia is the single most prevalent feature in individuals with CHARGE leading to deficient gross motor skills and ambulation. Identification of CHD7 as the major gene affected in CHARGE has enabled acceleration of research in this field. Great progress has been made in understanding the role of CHD7 in the development and function of the inner ear, as well as in related organs such as the middle ear and auditory and vestibular neural pathways. The goals of current research on CHD7 and CS are to (a) improve our understanding of the pathology caused by CHD7 pathogenic variants and (b) to provide better tools for prognosis and treatment. Current studies utilize cells and whole animals, from flies to mammals. The mouse is an excellent model for exploring mechanisms of Chd7 function in the ear, given the evolutionary conservation of ear structure, function, Chd7 expression, and similarity of mutant phenotypes between mice and humans. Newly recognized developmental functions for mouse Chd7 are shedding light on how abnormalities in CHD7 might lead to CS symptoms in humans. Here we review known human inner ear phenotypes associated with CHD7 pathogenic variants and CS, summarize progress toward diagnosis and treatment of inner ear-related pathologies, and explore new avenues for treatment based on basic science discoveries. © 2017 Wiley Periodicals, Inc.

Adjustment of interaural time difference in head related transfer functions based on listeners' anthropometry and its effect on sound localization

NASA Astrophysics Data System (ADS)

Suzuki, Yôiti; Watanabe, Kanji; Iwaya, Yukio; Gyoba, Jiro; Takane, Shouichi

2005-04-01

Because the transfer functions governing subjective sound localization (HRTFs) show strong individuality, sound localization systems based on synthesis of HRTFs require suitable HRTFs for individual listeners. However, it is impractical to obtain HRTFs for all listeners based on measurements. Improving sound localization by adjusting non-individualized HRTFs to a specific listener based on that listener's anthropometry might be a practical method. This study first developed a new method to estimate interaural time differences (ITDs) using HRTFs. Then correlations between ITDs and anthropometric parameters were analyzed using the canonical correlation method. Results indicated that parameters relating to head size, and shoulder and ear positions are significant. Consequently, it was attempted to express ITDs based on listener's anthropometric data. In this process, the change of ITDs as a function of azimuth angle was parameterized as a sum of sine functions. Then the parameters were analyzed using multiple regression analysis, in which the anthropometric parameters were used as explanatory variables. The predicted or individualized ITDs were installed in the nonindividualized HRTFs to evaluate sound localization performance. Results showed that individualization of ITDs improved horizontal sound localization.

Practical otic anatomy and physiology of the dog and cat.

PubMed

Njaa, Bradley L; Cole, Lynette K; Tabacca, Natalie

2012-11-01

Knowledge of the normal structure and function of the canine and feline ear is critical to be able to diagnose abnormalities that either involve the ear or originate within one or more of the ear compartments. In addition, a veterinarian must be aware of various structures within or associated with the ear so that they are not damaged or destroyed while treating an animal with otic disease. This article provides a brief discussion of the various anatomic features of the ear and normal physiology of portions of the ear. Copyright © 2012 Elsevier Inc. All rights reserved.

Alternative splicing of inner-ear-expressed genes.

PubMed

Wang, Yanfei; Liu, Yueyue; Nie, Hongyun; Ma, Xin; Xu, Zhigang

2016-09-01

Alternative splicing plays a fundamental role in the development and physiological function of the inner ear. Inner-ear-specific gene splicing is necessary to establish the identity and maintain the function of the inner ear. For example, exon 68 of Cadherin 23 (Cdh23) gene is subject to inner-ear-specific alternative splicing, and as a result, Cdh23(+ 68) is only expressed in inner ear hair cells. Alternative splicing along the tonotopic axis of the cochlea contributes to frequency tuning, particularly in lower vertebrates, such as chickens and turtles. Differential splicing of Kcnma1, which encodes for the α subunit of the Ca(2+)-activated K(+) channel (BK channel), has been suggested to affect the channel gating properties and is important for frequency tuning. Consequently, deficits in alternative splicing have been shown to cause hearing loss, as we can observe in Bronx Waltzer (bv) mice and Sfswap mutant mice. Despite the advances in this field, the regulation of alternative splicing in the inner ear remains elusive. Further investigation is also needed to clarify the mechanism of hearing loss caused by alternative splicing deficits.

Corpus callosum functioning in patients with normal pressure hydrocephalus before and after surgery.

PubMed

Mataró, Maria; Poca, Maria Antonia; Matarín, Mar; Sahuquillo, Juan; Sebastián, Nuria; Junqué, Carme

2006-05-01

Our aim was to evaluate corpus callosum functioning in a group of patients with normal pressure hydrocephalus (NPH) before and after shunting. Left ear-extinction under a dichotic listening task was evaluated in twenty-three patients with NPH, 30 patients with Alzheimer's disease and 30 aged controls. Patients with NPH had higher levels of left ear extinction than the control and Alzheimer's groups. Sixty-one percent of NPH patients exhibited left ear suppression, compared with 13% of Alzheimer's patients and 17% of controls. Following surgery, NPH patients showed a significant change in the degree of asymmetry in the dichotic listening task. Hydrocephalus was associated with left-ear extinction,which diminished after surgery. Our results may indicate reversible functional damage in the corpus callosum.

Effects of NSAIDs on the Inner Ear: Possible Involvement in Cochlear Protection

PubMed Central

Hoshino, Tomofumi; Tabuchi, Keiji; Hara, Akira

2010-01-01

Cyclooxygenase and lipoxygenase, two important enzymes involved in arachidonic acid metabolism, are major targets of non-steroidal anti-inflammatory drugs (NSAIDs). Recent investigations suggest that arachidonic cascades and their metabolites may be involved in maintaining inner ear functions. The excessive use of aspirin may cause tinnitus in humans and impairment of the outer hair cell functions in experimental animals. On the other hand, NSAIDs reportedly exhibit protective effects against various kinds of inner ear disorder. The present review summarizes the effects of NSAIDs on cochlear pathophysiology. NSAIDs are a useful ameliorative adjunct in the management of inner ear disorders. PMID:27713301

Age-related full-field motion change in baboon tympanic membrane

NASA Astrophysics Data System (ADS)

Gan, Rong Z.; Jiang, Shangyuan; Pineda, Mario

2018-05-01

Clinical observations indicate that the structure and function of the middle ear change from newborn to adult. However, due to the lack of young children's temporal bones for investigators, characterizations of the pediatric middle ear function and tissue mechanical properties are limited. Higher primates such as olive baboons (Papio anubis) ear specimens may provide alternative testing sources whose properties are likely to closely resemble those of humans. This paper reports our recent study on measurement of the tympanic membrane (TM) surface motion of baboon temporal bones in the age range from 6 months to young adult using the scanning laser Doppler vibrometry (SLDV). The full-field TM motion and the umbo displacement show that the mobility of the TM at frequencies below 2 kHz increased as age increases and the middle ear input impedance decreased with the age increase. The traveling-wave-like vibration modes in adult TMs started appearing at lower frequencies than that of young baboons. The results show the age-dependent middle ear function changes in baboons which may open a new research dimension to provide urgently needed data for biomechanical properties of young children ears.

Small Tympanic Membrane Perforations in the Inferior Quadrants Do Not Impact the Manubrium Vibration in Guinea Pigs

PubMed Central

Zhang, Xiuling; Dai, Yanhong; Zhang, Shuyi; She, Wandong; Du, Xiaoping; Shui, Xiuji

2012-01-01

Background It has been believed that location of the perforation has a significant impact on hearing loss. However, recent studies have demonstrated that the perforation sites had no impact on hearing loss. We measured the velocity and pattern of the manubrium vibration in guinea pigs with intact and perforated eardrum using a laser Doppler vibrometer in order to determine the effects of different location perforations on the middle ear transfer functions. Methods Two bullas from 2 guinea pigs were used to determine stability of the umbo velocities, and 12 bullas from six guinea pigs to determine the effects of different location perforations on sound transmission. The manubrium velocity was measured at three points on the manubrium in the frequencies of 0.5–8 kHz before and after a perforation was made. The sites of perforations were in anterior-inferior (AI) quadrants of left ears and posterior-inferior (PI) quadrants of right ears. Results The manubrium vibration velocity losses were noticed in the perforated ears only below 1.5 kHz. The maximum velocity loss was about 7 dB at 500 Hz with the PI perforation. No significant difference in the velocity loss was found between AI and PI perforations. The average ratio of short process velocity to the umbo velocity was approximately 0.5 at all frequencies. No significant differences were found before and after perforation at all frequencies (p>0.05) except 7 kHz (p = 0.004) for both AI and PI perforations. Conclusions The manubrium vibration velocity losses from eardrum perforation were frequency-dependent and the largest losses occur at low frequencies. Manubrium velocity losses caused by small acute inferior perforations in guinea pigs have no significant impact on middle ear sound transmission at any frequency tested. The manubrium vibration axis may be perpendicular to the manubrium below 8 kHz in guinea pigs. PMID:22238584

Cloning of calves from various somatic cell types of male and female adult, newborn and fetal cows.

PubMed

Kato, Y; Tani, T; Tsunoda, Y

2000-11-01

Twenty-four calves were cloned from six somatic cell types of female and male adult, newborn and fetal cows. The clones were derived from female cumulus (n = 3), oviduct (n = 2) and uterine (n = 2) cells, female and male skin cells (n = 10), and male ear (n = 5) and liver (n = 2) cells. On the basis of the number of cloned embryos transferred (n = 172) to surrogate cows, the overall rate of success was 14%, but based on the number of surrogate mothers that became pregnant (n = 50), the success rate was 48%. Cell nuclei from uterus, ear and liver cells, which have not been tested previously, developed into newborn calves after nuclear transfer into enucleated oocytes. To date, seven female and six male calves have survived: six of the females were from adult cells (cumulus (n = 3), oviduct (n = 2) and skin (n = 1) cells) and one was from newborn skin cells, whereas the male calves were derived from adult ear cells (n = 3), newborn liver and skin cells (n = 2), and fetal cells (n = 1). Clones derived from adult cells frequently aborted in the later stages of pregnancy and calves developing to term showed a higher number of abnormalities than did those derived from newborn or fetal cells. The telomeric DNA lengths in the ear cells of three male calves cloned from the ear cells of a bull aged 10 years were similar to those of the original bull. However, the telomeric DNA lengths from the white blood cells of the clones, although similar to those in an age-matched control, were shorter than those of the original bull, which indicates that telomeric shortening varies among tissues.

A novel buoyancy technique optimizes simulated microgravity conditions for whole sensory organ culture in rotating bioreactors.

PubMed

Arnold, Heinz J P; Müller, Marcus; Waldhaus, Jörg; Hahn, Hartmut; Löwenheim, Hubert

2010-02-01

Whole-organ culture of a sensory organ in a rotating wall vessel bioreactor provides a powerful in vitro model for physiological and pathophysiological investigation as previously demonstrated for the postnatal inner ear. The model is of specific relevance as a tool for regeneration research. In the immature inner ear explant, the density was only 1.29 g/cm(3). The high density of 1.68 g/cm(3) of the functionally mature organ resulted in enhanced settling velocity and deviation from its ideal circular orbital path causing enhanced shear stress. The morphometric and physical properties, as well as the dynamic motion patterns of explants, were analyzed and numerically evaluated by an orbital path index. Application of a novel buoyancy bead technique resulted in a 6.5- to 14.8-fold reduction of the settling velocity. The deviation of the explant from its ideal circular orbital path was adjusted as indicated by an optimum value for the orbital path index (-1.0). Shear stress exerted on the inner ear explant was consequently reduced 6.4- to 15.0-fold. The culture conditions for postnatal stages were optimized, and the preconditions for transferring this in vitro model toward mature high-density stages established. This buoyancy technique may also be useful in tissue engineering of other high-density structures.

Adipose-derived stromal cells enhance auditory neuron survival in an animal model of sensory hearing loss.

PubMed

Schendzielorz, Philipp; Vollmer, Maike; Rak, Kristen; Wiegner, Armin; Nada, Nashwa; Radeloff, Katrin; Hagen, Rudolf; Radeloff, Andreas

2017-10-01

A cochlear implant (CI) is an electronic prosthesis that can partially restore speech perception capabilities. Optimum information transfer from the cochlea to the central auditory system requires a proper functioning auditory nerve (AN) that is electrically stimulated by the device. In deafness, the lack of neurotrophic support, normally provided by the sensory cells of the inner ear, however, leads to gradual degeneration of auditory neurons with undesirable consequences for CI performance. We evaluated the potential of adipose-derived stromal cells (ASCs) that are known to produce neurotrophic factors to prevent neural degeneration in sensory hearing loss. For this, co-cultures of ASCs with auditory neurons have been studied, and autologous ASC transplantation has been performed in a guinea pig model of gentamicin-induced sensory hearing loss. In vitro ASCs were neuroprotective and considerably increased the neuritogenesis of auditory neurons. In vivo transplantation of ASCs into the scala tympani resulted in an enhanced survival of auditory neurons. Specifically, peripheral AN processes that are assumed to be the optimal activation site for CI stimulation and that are particularly vulnerable to hair cell loss showed a significantly higher survival rate in ASC-treated ears. ASC transplantation into the inner ear may restore neurotrophic support in sensory hearing loss and may help to improve CI performance by enhanced AN survival. Copyright © 2017 International Society for Cellular Therapy. Published by Elsevier Inc. All rights reserved.

Comparative genomics of maize ear rot pathogens reveals expansion of carbohydrate-active enzymes and secondary metabolism backbone genes in Stenocarpella maydis.

PubMed

Zaccaron, Alex Z; Woloshuk, Charles P; Bluhm, Burton H

2017-11-01

Stenocarpella maydis is a plant pathogenic fungus that causes Diplodia ear rot, one of the most destructive diseases of maize. To date, little information is available regarding the molecular basis of pathogenesis in this organism, in part due to limited genomic resources. In this study, a 54.8 Mb draft genome assembly of S. maydis was obtained with Illumina and PacBio sequencing technologies, and analyzed. Comparative genomic analyses with the predominant maize ear rot pathogens Aspergillus flavus, Fusarium verticillioides, and Fusarium graminearum revealed an expanded set of carbohydrate-active enzymes for cellulose and hemicellulose degradation in S. maydis. Analyses of predicted genes involved in starch degradation revealed six putative α-amylases, four extracellular and two intracellular, and two putative γ-amylases, one of which appears to have been acquired from bacteria via horizontal transfer. Additionally, 87 backbone genes involved in secondary metabolism were identified, which represents one of the largest known assemblages among Pezizomycotina species. Numerous secondary metabolite gene clusters were identified, including two clusters likely involved in the biosynthesis of diplodiatoxin and chaetoglobosins. The draft genome of S. maydis presented here will serve as a useful resource for molecular genetics, functional genomics, and analyses of population diversity in this organism. Copyright © 2017 British Mycological Society. Published by Elsevier Ltd. All rights reserved.

Gerbil middle-ear sound transmission from 100 Hz to 60 kHz1

PubMed Central

Ravicz, Michael E.; Cooper, Nigel P.; Rosowski, John J.

2008-01-01

Middle-ear sound transmission was evaluated as the middle-ear transfer admittance HMY (the ratio of stapes velocity to ear-canal sound pressure near the umbo) in gerbils during closed-field sound stimulation at frequencies from 0.1 to 60 kHz, a range that spans the gerbil’s audiometric range. Similar measurements were performed in two laboratories. The HMY magnitude (a) increased with frequency below 1 kHz, (b) remained approximately constant with frequency from 5 to 35 kHz, and (c) decreased substantially from 35 to 50 kHz. The HMY phase increased linearly with frequency from 5 to 35 kHz, consistent with a 20–29 μs delay, and flattened at higher frequencies. Measurements from different directions showed that stapes motion is predominantly pistonlike except in a narrow frequency band around 10 kHz. Cochlear input impedance was estimated from HMY and previously-measured cochlear sound pressure. Results do not support the idea that the middle ear is a lossless matched transmission line. Results support the ideas that (1) middle-ear transmission is consistent with a mechanical transmission line or multiresonant network between 5 and 35 kHz and decreases at higher frequencies, (2) stapes motion is pistonlike over most of the gerbil auditory range, and (3) middle-ear transmission properties are a determinant of the audiogram. PMID:18646983

The acoustical cues to sound location in the Guinea pig (cavia porcellus)

PubMed Central

Greene, Nathanial T; Anbuhl, Kelsey L; Williams, Whitney; Tollin, Daniel J.

2014-01-01

There are three main acoustical cues to sound location, each attributable to space-and frequency-dependent filtering of the propagating sound waves by the outer ears, head, and torso: Interaural differences in time (ITD) and level (ILD) as well as monaural spectral shape cues. While the guinea pig has been a common model for studying the anatomy, physiology, and behavior of binaural and spatial hearing, extensive measurements of their available acoustical cues are lacking. Here, these cues were determined from directional transfer functions (DTFs), the directional components of the head-related transfer functions, for eleven adult guinea pigs. In the frontal hemisphere, monaural spectral notches were present for frequencies from ~10 to 20 kHz; in general, the notch frequency increased with increasing sound source elevation and in azimuth toward the contralateral ear. The maximum ITDs calculated from low-pass filtered (2 kHz cutoff frequency) DTFs were ~250 µs, whereas the maximum ITD measured with low frequency tone pips was over 320 µs. A spherical head model underestimates ITD magnitude under normal conditions, but closely approximates values when the pinnae were removed. Interaural level differences (ILDs) strongly depended on location and frequency; maximum ILDs were < 10 dB for frequencies < 4 kHz and were as large as 40 dB for frequencies > 10 kHz. Removal of the pinna reduced the depth and sharpness of spectral notches, altered the acoustical axis, and reduced the acoustical gain, ITDs, and ILDs; however, spectral shape features and acoustical gain were not completely eliminated, suggesting a substantial contribution of the head and torso in altering the sounds present at the tympanic membrane. PMID:25051197

How brain asymmetry relates to performance – a large-scale dichotic listening study

PubMed Central

Hirnstein, Marco; Hugdahl, Kenneth; Hausmann, Markus

2014-01-01

All major mental functions including language, spatial and emotional processing are lateralized but how strongly and to which hemisphere is subject to inter- and intraindividual variation. Relatively little, however, is known about how the degree and direction of lateralization affect how well the functions are carried out, i.e., how lateralization and task performance are related. The present study therefore examined the relationship between lateralization and performance in a dichotic listening task for which we had data available from 1839 participants. In this task, consonant-vowel syllables are presented simultaneously to the left and right ear, such that each ear receives a different syllable. When asked which of the two they heard best, participants typically report more syllables from the right ear, which is a marker of left-hemispheric speech dominance. We calculated the degree of lateralization (based on the difference between correct left and right ear reports) and correlated it with overall response accuracy (left plus right ear reports). In addition, we used reference models to control for statistical interdependency between left and right ear reports. The results revealed a u-shaped relationship between degree of lateralization and overall accuracy: the stronger the left or right ear advantage, the better the overall accuracy. This u-shaped asymmetry-performance relationship consistently emerged in males, females, right-/non-right-handers, and different age groups. Taken together, the present study demonstrates that performance on lateralized language functions depends on how strongly these functions are lateralized. The present study further stresses the importance of controlling for statistical interdependency when examining asymmetry-performance relationships in general. PMID:24427151

Lamellar projections in the endolymphatic sac act as a relief valve to regulate inner ear pressure

PubMed Central

Swinburne, Ian A; Mosaliganti, Kishore R; Upadhyayula, Srigokul; Liu, Tsung-Li; Hildebrand, David G C; Tsai, Tony Y -C; Chen, Anzhi; Al-Obeidi, Ebaa; Fass, Anna K; Malhotra, Samir; Engert, Florian; Lichtman, Jeff W; Kirchausen, Tomas; Betzig, Eric

2018-01-01

The inner ear is a fluid-filled closed-epithelial structure whose function requires maintenance of an internal hydrostatic pressure and fluid composition. The endolymphatic sac (ES) is a dead-end epithelial tube connected to the inner ear whose function is unclear. ES defects can cause distended ear tissue, a pathology often seen in hearing and balance disorders. Using live imaging of zebrafish larvae, we reveal that the ES undergoes cycles of slow pressure-driven inflation followed by rapid deflation. Absence of these cycles in lmx1bb mutants leads to distended ear tissue. Using serial-section electron microscopy and adaptive optics lattice light-sheet microscopy, we find a pressure relief valve in the ES comprised of partially separated apical junctions and dynamic overlapping basal lamellae that separate under pressure to release fluid. We propose that this lmx1-dependent pressure relief valve is required to maintain fluid homeostasis in the inner ear and other fluid-filled cavities. PMID:29916365

Anisotropic yield function capable of predicting eight ears

NASA Astrophysics Data System (ADS)

Yoon, J. H.; Cazacu, O.

2011-08-01

Deep drawing of a cylindrical cup from a rolled sheet is one of the typical forming operations where the effect of this anisotropy is most evident. Indeed, it is well documented in the literature that the number of ears and the shape of the earing pattern correlate with the r-values profile. For the strongly textured aluminum alloy AA 5042 (Numisheet Benchmark 2011), the experimental r-value distribution has two minima between the rolling and transverse direction data provided for this show that the r-value along the transverse direction (TD) is five times larger than the value corresponding to the rolling direction. Therefore, it is expected that there are more that the earing profile has more than four ears. The main objective of this paper is to assess whether a new form of CPB06ex2 yield function (Plunkett et al. (2008)) tailored for metals with no tension-compression asymmetry is capable of predicting more than four ears for this material.

The Role of Zic Genes in Inner Ear Development in the Mouse: Exploring Mutant Mouse Phenotypes

PubMed Central

Chervenak, Andrew P.; Bank, Lisa M.; Thomsen, Nicole; Glanville-Jones, Hannah C; Skibo, Jonathan; Millen, Kathleen J.; Arkell, Ruth M.; Barald, Kate F.

2014-01-01

Background Murine Zic genes (Zic1-5) are expressed in the dorsal hindbrain and in periotic mesenchyme (POM) adjacent to the developing inner ear. Zic genes are involved in developmental signaling pathways in many organ systems, including the ear, although their exact roles haven't been fully elucidated. This report examines the role of Zic1, Zic2, and Zic4 during inner ear development in mouse mutants in which these Zic genes are affected Results Zic1/Zic4 double mutants don't exhibit any apparent defects in inner ear morphology. By contrast, inner ears from Zic2kd/kd and Zic2Ku/Ku mutants have severe but variable morphological defects in endolymphatic duct/sac and semicircular canal formation and in cochlear extension in the inner ear. Analysis of otocyst patterning in the Zic2Ku/Ku mutants by in situ hybridization showed changes in the expression patterns of Gbx2 and Pax2. Conclusions The experiments provide the first genetic evidence that the Zic genes are required for morphogenesis of the inner ear. Zic2 loss-of-function doesn't prevent initial otocyst patterning but leads to molecular abnormalities concomitant with morphogenesis of the endolymphatic duct. Functional hearing deficits often accompany inner ear dysmorphologies, making Zic2 a novel candidate gene for ongoing efforts to identify the genetic basis of human hearing loss. PMID:25178196

The Transplantation of hBM-MSCs Increases Bone Neo-Formation and Preserves Hearing Function in the Treatment of Temporal Bone Defects - on the Experience of Two Month Follow Up.

PubMed

Školoudík, Lukáš; Chrobok, Viktor; Kočí, Zuzana; Popelář, Jiří; Syka, Josef; Laco, Jan; Filipová, Alžběta; Syková, Eva; Filip, Stanislav

2018-06-03

Temporal bone reconstruction is a persisting problem following middle ear cholesteatoma surgery. Seeking to advance the clinical transfer of stem cell therapy we attempted the reconstruction of temporal bone using a composite bioartificial graft based on a hydroxyapatite bone scaffold combined with human bone marrow-derived mesenchymal stromal cells (hBM-MSCs). The aim of this study was to evaluate the effect of the combined biomaterial on the healing of postoperative temporal bone defects and the preservation of physiological hearing functions in a guinea pig model. The treatment's effect could be observed at 1 and 2 months after implantation of the biomaterial, as opposed to the control group. The clinical evaluation of our results included animal survival, clinical signs of an inflammatory response, and exploration of the tympanic bulla. Osteogenesis, angiogenesis, and inflammation were evaluated by histopathological analyses, whereas hBM-MSCs survival was evaluated by immunofluorescence assays. Hearing capacity was evaluated by objective audiometric methods, i.e. auditory brainstem responses and otoacoustic emission. Our study shows that hBM-MSCs, in combination with hydroxyapatite scaffolds, improves the repair of bone defects providing a safe and effective alternative in their treatment following middle ear surgery due to cholesteatoma.

Anatomy, Physiology and Function of the Auditory System

NASA Astrophysics Data System (ADS)

Kollmeier, Birger

The human ear consists of the outer ear (pinna or concha, outer ear canal, tympanic membrane), the middle ear (middle ear cavity with the three ossicles malleus, incus and stapes) and the inner ear (cochlea which is connected to the three semicircular canals by the vestibule, which provides the sense of balance). The cochlea is connected to the brain stem via the eighth brain nerve, i.e. the vestibular cochlear nerve or nervus statoacusticus. Subsequently, the acoustical information is processed by the brain at various levels of the auditory system. An overview about the anatomy of the auditory system is provided by Figure 1.

A tympanal insect ear exploits a critical oscillator for active amplification and tuning.

PubMed

Mhatre, Natasha; Robert, Daniel

2013-10-07

A dominant theme of acoustic communication is the partitioning of acoustic space into exclusive, species-specific niches to enable efficient information transfer. In insects, acoustic niche partitioning is achieved through auditory frequency filtering, brought about by the mechanical properties of their ears. The tuning of the antennal ears of mosquitoes and flies, however, arises from active amplification, a process similar to that at work in the mammalian cochlea. Yet, the presence of active amplification in the other type of insect ears--tympanal ears--has remained uncertain. Here we demonstrate the presence of active amplification and adaptive tuning in the tympanal ear of a phylogenetically basal insect, a tree cricket. We also show that the tree cricket exploits critical oscillator-like mechanics, enabling high auditory sensitivity and tuning to conspecific songs. These findings imply that sophisticated auditory mechanisms may have appeared even earlier in the evolution of hearing and acoustic communication than currently appreciated. Our findings also raise the possibility that frequency discrimination and directional hearing in tympanal systems may rely on physiological nonlinearities, in addition to mechanical properties, effectively lifting some of the physical constraints placed on insects by their small size [6] and prompting an extensive reexamination of invertebrate audition. Copyright © 2013 The Authors. Published by Elsevier Inc. All rights reserved.

Reconstruction of Punitive Ear Amputations in Uganda: A Unique Surgical Burden of Disease.

PubMed

Dusseldorp, Joseph; Hodges, Andrew; Patel, Anup; Marchac, Alexandre; Firmin, Françoise

2015-06-01

Over the course of 12 months, a plastic surgical team from Paris, France, undertook 2 intensive ear reconstruction missions with plastic surgeons from the CoRSU Rehabilitation Hospital in Uganda. A cohort of over 30 adult women was assessed having been subjected to ear amputations by members of the Lords Resistance Army in Northern Uganda in the 1990s. The patients were identified, mobilized, and transferred to Kampala for surgery by a charitable arm of the Watoto Church, known as Living Hope. The surgical team performed 15 ear reconstruction cases during the first 1-week mission and 16 ear reconstruction cases during the second 1-week mission. All cases were reconstructed successfully using the 2-stage autologous auricular reconstruction method advocated by the senior author (FF). Local skin was used to cover the costal cartilage framework in the first stage without need for temporo-parietal fascial flaps. Technical challenges included the older age of patients and ossified costal cartilage, high prevalence of HIV positivity, bilateral amputation, and difficulty of surgical follow-up. The main modifications to standard practice were routine pre-op testing of the costal cartilage, pre-op viral load and CD4 count screening in HIV-positive patients, simultaneous bilateral first-stage ear reconstruction, prolonged hospital stay, and implementation of routine surgical counting procedures.

Early postnatal virus inoculation into the scala media achieved extensive expression of exogenous green fluorescent protein in the inner ear and preserved auditory brainstem response thresholds.

PubMed

Wang, Yunfeng; Sun, Yu; Chang, Qing; Ahmad, Shoeb; Zhou, Binfei; Kim, Yeunjung; Li, Huawei; Lin, Xi

2013-01-01

Gene transfer into the inner ear is a promising approach for treating sensorineural hearing loss. The special electrochemical environment of the scala media raises a formidable challenge for effective gene delivery at the same time as keeping normal cochlear function intact. The present study aimed to define a suitable strategy for preserving hearing after viral inoculation directly into the scala media performed at various postnatal developmental stages. We assessed transgene expression of green fluorescent protein (GFP) mediated by various types of adeno-associated virus (AAV) and lentivirus (LV) in the mouse cochlea. Auditory brainstem responses were measured 30 days after inoculation to assess effects on hearing. Patterns of GFP expression confirmed extensive exogenous gene expression in various types of cells lining the endolymphatic space. The use of different viral vectors and promoters resulted in specific cellular GFP expression patterns. AAV2/1 with cytomegalovirus promoter apparently gave the best results for GFP expression in the supporting cells. Histological examination showed normal cochlear morphology and no hair cell loss after either AAV or LV injections. We found that hearing thresholds were not significantly changed when the injections were performed in mice younger than postnatal day 5, regardless of the type of virus tested. Viral inoculation and expression in the inner ear for the restoration of hearing must not damage cochlear function. Using normal hearing mice as a model, we have achieved this necessary step, which is required for the treatment of many types of congenital deafness that require early intervention. Copyright © 2013 John Wiley & Sons, Ltd.

Production of heterozygous alpha 1,3-galactosyltransferase (GGTA1) knock-out transgenic miniature pigs expressing human CD39.

PubMed

Choi, Kimyung; Shim, Joohyun; Ko, Nayoung; Eom, Heejong; Kim, Jiho; Lee, Jeong-Woong; Jin, Dong-Il; Kim, Hyunil

2017-04-01

Production of transgenic pigs for use as xenotransplant donors is a solution to the severe shortage of human organs for transplantation. The first barrier to successful xenotransplantation is hyperacute rejection, a rapid, massive humoral immune response directed against the pig carbohydrate GGTA1 epitope. Platelet activation, adherence, and clumping, all major features of thrombotic microangiopathy, are inevitable results of immune-mediated transplant rejection. Human CD39 rapidly hydrolyzes ATP and ADP to AMP; AMP is hydrolyzed by ecto-5'-nucleotidase (CD73) to adenosine, an anti-thrombotic and cardiovascular protective mediator. In this study, we developed a vector-based strategy for ablation of GGTA1 function and concurrent expression of human CD39 (hCD39). An hCD39 expression cassette was constructed to target exon 4 of GGTA1. We established heterozygous GGTA1 knock-out cell lines expressing hCD39 from pig ear fibroblasts for somatic cell nuclear transfer (SCNT). We also described production of heterozygous GGTA1 knock-out piglets expressing hCD39 and analyzed expression and function of the transgene. Human CD39 was expressed in heart, kidney and aorta. Human CD39 knock-in heterozygous ear fibroblast from transgenic cloned pigs, but not in non-transgenic pig's cells. Expression of GGTA1 gene was lower in the knock-in heterozygous ear fibroblast from transgenic pigs compared to the non-transgenic pig's cell. The peripheral blood mononuclear cells (PBMC) from the transgenic pigs were more resistant to lysis by pooled complement-preserved normal human serum than that from wild type (WT) pig. Accordingly, GGTA1 mutated piglets expressing hCD39 will provide a new organ source for xenotransplantation research.

Molecular mechanisms of inner ear development.

PubMed

Wu, Doris K; Kelley, Matthew W

2012-08-01

The inner ear is a structurally complex vertebrate organ built to encode sound, motion, and orientation in space. Given its complexity, it is not surprising that inner ear dysfunction is a relatively common consequence of human genetic mutation. Studies in model organisms suggest that many genes currently known to be associated with human hearing impairment are active during embryogenesis. Hence, the study of inner ear development provides a rich context for understanding the functions of genes implicated in hearing loss. This chapter focuses on molecular mechanisms of inner ear development derived from studies of model organisms.

Structures that Contribute to Middle-Ear Admittance in Chinchilla

PubMed Central

Rosowski, John J.; Ravicz, Michael E.; Songer, Jocelyn E.

2009-01-01

We describe measurements of middle-ear input admittance in chinchillas (Chinchilla lanigera) before and after various manipulations that define the contributions of different middle-ear components to function. The chinchilla’s middle-ear air spaces have a large effect on the low-frequency compliance of the middle ear, and removing the influences of these spaces reveals a highly admittant tympanic membrane and ossicular chain. Measurements of the admittance of the air spaces reveal that the high-degree of segmentation of these spaces has only a small effect on the admittance. Draining the cochlea further increases the middle-ear admittance at low frequencies and removes a low-frequency (less than 300 Hz) level dependence in the admittance. Spontaneous or sound-driven contractions of the middle-ear muscles in deeply anesthetized animals were associated with significant changes in middle-ear admittance. PMID:16944166

Adenovirus Vectors Target Several Cell Subtypes of Mammalian Inner Ear In Vivo

PubMed Central

Li, Wenyan; Shen, Jun

2016-01-01

Mammalian inner ear harbors diverse cell types that are essential for hearing and balance. Adenovirus is one of the major vectors to deliver genes into the inner ear for functional studies and hair cell regeneration. To identify adenovirus vectors that target specific cell subtypes in the inner ear, we studied three adenovirus vectors, carrying a reporter gene encoding green fluorescent protein (GFP) from two vendors or with a genome editing gene Cre recombinase (Cre), by injection into postnatal days 0 (P0) and 4 (P4) mouse cochlea through scala media by cochleostomy in vivo. We found three adenovirus vectors transduced mouse inner ear cells with different specificities and expression levels, depending on the type of adenoviral vectors and the age of mice. The most frequently targeted region was the cochlear sensory epithelium, including auditory hair cells and supporting cells. Adenovirus with GFP transduced utricular supporting cells as well. This study shows that adenovirus vectors are capable of efficiently and specifically transducing different cell types in the mammalian inner ear and provides useful tools to study inner ear gene function and to evaluate gene therapy to treat hearing loss and vestibular dysfunction. PMID:28116172

Identification of Adeno-Associated Viral Vectors That Target Neonatal and Adult Mammalian Inner Ear Cell Subtypes

PubMed Central

Shu, Yilai; Tao, Yong; Wang, Zhengmin; Tang, Yong; Li, Huawei; Dai, Pu; Gao, Guangping; Chen, Zheng-Yi

2016-01-01

The mammalian inner ear consists of diverse cell types with important functions. Gene mutations in these diverse cell types have been found to underlie different forms of genetic hearing loss. Targeting these mutations for gene therapy development represents a future therapeutic strategy to treat hearing loss. Adeno-associated viral (AAV) vectors have become the vector of choice for gene delivery in animal models in vivo. To identify AAV vectors that target inner ear cell subtypes, we systemically screened 12 AAV vectors with different serotypes (AAV1, 2, 5, 6, 6.2, 7, 8, 9, rh.8, rh.10, rh.39, and rh.43) that carry a reporter gene GFP in neonatal and adult mice by microinjection in vivo. We found that most AAVs infect both neonatal and adult inner ear, with different specificities and expression levels. The inner ear cochlear sensory epithelial region, which includes auditory hair cells and supporting cells, is most frequently targeted for gene delivery. Expression of the transgene is sustained, and neonatal inner ear delivery does not adversely affect hearing. Adult inner ear injection of AAV has a similar infection pattern as the younger inner ear, with the exception that outer hair cell death caused by the injection procedure can lead to hearing loss. In the adult, more so than in the neonatal mice, cell types infected and efficiency of infection are correlated with the site of injection. Most infected cells survive in neonatal and adult inner ears. The study adds to the list of AAV vectors that transduce the mammalian inner ear efficiently, providing the tools that are important to study inner ear gene function and for the development of gene therapy to treat hearing loss. PMID:27342665

Sound transmission in archaic and modern whales: anatomical adaptations for underwater hearing.

PubMed

Nummela, Sirpa; Thewissen, J G M; Bajpai, Sunil; Hussain, Taseer; Kumar, Kishor

2007-06-01

The whale ear, initially designed for hearing in air, became adapted for hearing underwater in less than ten million years of evolution. This study describes the evolution of underwater hearing in cetaceans, focusing on changes in sound transmission mechanisms. Measurements were made on 60 fossils of whole or partial skulls, isolated tympanics, middle ear ossicles, and mandibles from all six archaeocete families. Fossil data were compared with data on two families of modern mysticete whales and nine families of modern odontocete cetaceans, as well as five families of noncetacean mammals. Results show that the outer ear pinna and external auditory meatus were functionally replaced by the mandible and the mandibular fat pad, which posteriorly contacts the tympanic plate, the lateral wall of the bulla. Changes in the ear include thickening of the tympanic bulla medially, isolation of the tympanoperiotic complex by means of air sinuses, functional replacement of the tympanic membrane by a bony plate, and changes in ossicle shapes and orientation. Pakicetids, the earliest archaeocetes, had a land mammal ear for hearing in air, and used bone conduction underwater, aided by the heavy tympanic bulla. Remingtonocetids and protocetids were the first to display a genuine underwater ear where sound reached the inner ear through the mandibular fat pad, the tympanic plate, and the middle ear ossicles. Basilosaurids and dorudontids showed further aquatic adaptations of the ossicular chain and the acoustic isolation of the ear complex from the skull. The land mammal ear and the generalized modern whale ear are evolutionarily stable configurations, two ends of a process where the cetacean mandible might have been a keystone character. 2007 Wiley-Liss, Inc.

Adoptive Cellular Gene Therapy for the Treatment of Experimental Autoimmune Polychondritis Ear Disease.

PubMed

Zhou, Bin; Liao, Yonggan; Guo, Yunkai; Tarner, Ingo H; Liao, Chunfen; Chen, Sisi; Kermany, Mohammad Habiby; Tu, Hanjun; Zhong, Sen; Chen, Peijie

2017-01-01

In the past, the clinical therapy for autoimmune diseases, such as autoimmune polychondritis ear disease, was mostly limited to nonspecific immunosuppressive agents, which could lead to variable responses. Currently, gene therapy aims at achieving higher specificity and less adverse effects. This concept utilizes the adoptive transfer of autologous T cells that have been retrovirally transduced ex vivo to express and deliver immunoregulatory gene products to sites of autoimmune inflammation. In the animal model of collagen-induced autoimmune polychondritis ear disease (CIAPED), the adoptive transfer of IL-12p40-expressing collagen type II (CII)-specific CD4+ T-cell hybridomas resulted in a significantly lower disease incidence and severity compared with untreated or vector-only-treated animals. In vivo cell detection using bioluminescent labels showed that transferred CII-reactive T-cell hybridomas accumulated in the inflamed earlobes of the mice with CIAPED. In vitro analysis demonstrated that IL-12p40-transduced T cells did not affect antigen-specific T-cell activation or systemic anti-CII Ab responses. However, IL-12p40-transduced T cells suppressed IFN-γ and augmented IL-4 production, indicating their potential to act therapeutically by interrupting Th1-mediated inflammatory responses via augmenting Th2 responses. These results indicate that the local delivery of IL-12p40 by T cells could inhibit CIAPED by suppressing autoimmune responses at the site of inflammation. © 2017 S. Karger AG, Basel.

Molecular Mechanisms of Inner Ear Development

PubMed Central

Wu, Doris K.; Kelley, Matthew W.

2012-01-01

The inner ear is a structurally complex vertebrate organ built to encode sound, motion, and orientation in space. Given its complexity, it is not surprising that inner ear dysfunction is a relatively common consequence of human genetic mutation. Studies in model organisms suggest that many genes currently known to be associated with human hearing impairment are active during embryogenesis. Hence, the study of inner ear development provides a rich context for understanding the functions of genes implicated in hearing loss. This chapter focuses on molecular mechanisms of inner ear development derived from studies of model organisms. PMID:22855724

Ear asymmetries in middle-ear, cochlear, and brainstem responses in human infants

PubMed Central

Keefe, Douglas H.; Gorga, Michael P.; Jesteadt, Walt; Smith, Lynette M.

2008-01-01

In 2004, Sininger and Cone-Wesson examined asymmetries in the signal-to-noise ratio (SNR) of otoacoustic emissions (OAE) in infants, reporting that distortion-product (DP)OAE SNR was larger in the left ear, whereas transient-evoked (TE)OAE SNR was larger in the right. They proposed that cochlear and brainstem asymmetries facilitate development of brain-hemispheric specialization for sound processing. Similarly, in 2006 Sininger and Cone-Wesson described ear asymmetries mainly favoring the right ear in infant auditory brainstem responses (ABRs). The present study analyzed 2640 infant responses to further explore these effects. Ear differences in OAE SNR, signal, and noise were evaluated separately and across frequencies (1.5, 2, 3, and 4 kHz), and ABR asymmetries were compared with cochlear asymmetries. Analyses of ear-canal reflectance and admittance showed that asymmetries in middle-ear functioning did not explain cochlear and brainstem asymmetries. Current results are consistent with earlier studies showing right-ear dominance for TEOAE and ABR. Noise levels were higher in the right ear for OAEs and ABRs, causing ear asymmetries in SNR to differ from those in signal level. No left-ear dominance for DPOAE signal was observed. These results do not support a theory that ear asymmetries in cochlear processing mimic hemispheric brain specialization for auditory processing. PMID:18345839

Sensitivity and specificity of eustachian tube function tests in adults.

PubMed

Doyle, William J; Swarts, J Douglas; Banks, Julianne; Casselbrant, Margaretha L; Mandel, Ellen M; Alper, Cuneyt M

2013-07-01

The study demonstrates the utility of eustachian tube (ET) function (ETF) test results for accurately assigning ears to disease state. To determine if ETF tests can identify ears with physician-diagnosed ET dysfunction (ETD) in a mixed population at high sensitivity and specificity and to define the interrelatedness of ETF test parameters. Through use of the forced-response, inflation-deflation, Valsalva, and sniffing tests, ETF was evaluated in 15 control ears of adult subjects after unilateral myringotomy (group 1) and in 23 ears of 19 adult subjects with ventilation tubes inserted for ETD (group 2). Data were analyzed using logistic regression including each parameter independently and then a step-down discriminant analysis including all ETF test parameters to predict group assignment. Factor analysis operating over all parameters was used to explore relatedness. ETF testing. ETF parameters for the forced response, inflation-deflation, Valsalva, and sniffing tests measured in 15 control ears of adult subjects after unilateral myringotomy (group 1) and in 23 ears of 19 adult subjects with ventilation tubes inserted for ETD (group 2). The discriminant analysis identified 4 ETF test parameters (Valsalva, ET opening pressure, dilatory efficiency, and percentage of positive pressure equilibrated) that together correctly assigned ears to group 2 at a sensitivity of 95% and a specificity of 83%. Individual parameters representing the efficiency of ET opening during swallowing showed moderately accurate assignments of ears to their respective groups. Three factors captured approximately 98% of the variance among parameters: the first had negative loadings of the ETF structural parameters; the second had positive loadings of the muscle-assisted ET opening parameters; and the third had negative loadings of the muscle-assisted ET opening parameters and positive loadings of the structural parameters. These results show that ETF tests can correctly assign individual ears to physician-diagnosed ETD with high sensitivity and specificity and that ETF test parameters can be grouped into structural-functional categories.

Comparison of effects of dry versus wet swallowing on Eustachian tube function via a nine-step inflation/deflation test.

PubMed

Adali, M Kemal; Uzun, Cem

2005-09-01

The aim of the present study is to evaluate the effect of swallowing type (dry versus wet) on the outcome of a nine-step inflation/deflation tympanometric Eustachian tube function (ETF) test in healthy adults. Fourteen normal healthy volunteers, between 19 and 28 years of age, were included in the study. The nine-step test was performed in two different test procedures: (1) test with dry swallows (dry test procedure) and (2) test with liquid swallows (wet test procedure). If the equilibration of middle-ear (ME) pressure was successful in all the steps of the nine-step test, ETF was considered 'Good'. Otherwise, the test was considered 'Poor', and the test was repeated at a second session. In the dry test procedure, ETF was 'Good' in 21 ears at the first session and in 24 ears after the second session (p > 0.05). However, in the wet test procedure, ETF was 'Good' in 13 ears at the first session and in 21 ears after the second session (p < 0.05). At the first session, ETF was 'Good' in 21 and 13 ears in the dry and wet test procedures, respectively. The difference was statistically significant (p < 0.05). However, after the second session, the overall number of ears with 'Good' tubal function was almost the same in both test procedures (24 ears at dry test procedures versus 21 ears at wet test procedures;p > 0.05). Dry swallowing seems to be more effective for the equilibration of ME pressure. Thus, a single-session dependent evaluation of ETF may be efficient for the dry test procedure of the nine-step test. Swallowing with water may be easier for subjects, but a repetition of the test at a second session may be necessary when the test result is 'Poor'.

A comprehensive catalogue of the coding and non-coding transcripts of the human inner ear

PubMed Central

Corneveaux, Jason J.; Ohmen, Jeffrey; White, Cory; Allen, April N.; Lusis, Aldons J.; Van Camp, Guy; Huentelman, Matthew J.; Friedman, Rick A.

2015-01-01

The mammalian inner ear consists of the cochlea and the vestibular labyrinth (utricle, saccule, and semicircular canals), which participate in both hearing and balance. Proper development and life-long function of these structures involves a highly complex coordinated system of spatial and temporal gene expression. The characterization of the inner ear transcriptome is likely important for the functional study of auditory and vestibular components, yet, primarily due to tissue unavailability, detailed expression catalogues of the human inner ear remain largely incomplete. We report here, for the first time, comprehensive transcriptome characterization of the adult human cochlea, ampulla, saccule and utricle of the vestibule obtained from patients without hearing abnormalities. Using RNA-Seq, we measured the expression of >50,000 predicted genes corresponding to approximately 200,000 transcripts, in the adult inner ear and compared it to 32 other human tissues. First, we identified genes preferentially expressed in the inner ear, and unique either to the vestibule or cochlea. Next, we examined expression levels of specific groups of potentially interesting RNAs, such as genes implicated in hearing loss, long non-coding RNAs, pseudogenes and transcripts subject to nonsense mediated decay (NMD). We uncover the spatial specificity of expression of these RNAs in the hearing/balance system, and reveal evidence of tissue specific NMD. Lastly, we investigated the non-syndromic deafness loci to which no gene has been mapped, and narrow the list of potential candidates for each locus. These data represent the first high-resolution transcriptome catalogue of the adult human inner ear. A comprehensive identification of coding and non-coding RNAs in the inner ear will enable pathways of auditory and vestibular function to be further defined in the study of hearing and balance. Expression data are freely accessible at https://www.tgen.org/home/research/research-divisions/neurogenomics/supplementary-data/inner-ear-transcriptome.aspx PMID:26341477

Between-Frequency and Between-Ear Gap Detections and Their Relation to Perception of Stop Consonants.

PubMed

Mori, Shuji; Oyama, Kazuki; Kikuchi, Yousuke; Mitsudo, Takako; Hirose, Nobuyuki

2015-01-01

The objective of this study was to examine the hypothesis that between-channel gap detection, which includes between-frequency and between-ear gap detection, and perception of stop consonants, which is mediated by the length of voice-onset time (VOT), share common mechanisms, namely relative-timing operation in monitoring separate perceptual channels. The authors measured gap detection thresholds and identification functions of /ba/ and /pa/ along VOT in 49 native young adult Japanese listeners. There were three gap detection tasks. In the between-frequency task, the leading and trailing markers differed in terms of center frequency (Fc). The leading marker was a broadband noise of 10 to 20,000 Hz. The trailing marker was a 0.5-octave band-passed noise of 1000-, 2000-, 4000-, or 8000-Hz Fc. In the between-ear task, the two markers were spectrally identical but presented to separate ears. In the within-frequency task, the two spectrally identical markers were presented to the same ear. The /ba/-/pa/ identification functions were obtained in a task in which the listeners were presented synthesized speech stimuli of varying VOTs from 10 to 46 msec and asked to identify them as /ba/ or /pa/. The between-ear gap thresholds were significantly positively correlated with the between-frequency gap thresholds (except those obtained with the trailing marker of 4000-Hz Fc). The between-ear gap thresholds were not significantly correlated with the within-frequency gap thresholds, which were significantly correlated with all the between-frequency gap thresholds. The VOT boundaries and slopes of /ba/-/pa/ identification functions were not significantly correlated with any of these gap thresholds. There was a close relation between the between-ear and between-frequency gap detection, supporting the view that these two types of gap detection share common mechanisms of between-channel gap detection. However, there was no evidence for a relation between the perception of stop consonants and the between-frequency/ear gap detection in native Japanese speakers.

The Effects of Middle Ear Pressure on Hearing.

DTIC Science & Technology

1984-04-30

Miller, J,M.: Choline salicylate : Effects on cochlear function. Arch. Otolaryngol. 99: 304-308, 1974. *12. Miller, J.M. and Holmquist, J.: An animal model...for study of eustachian tube and middle ear function. Scand. Audiol. 3: 63-68, 1974. 13. McPherson, D. and Miller, J.: Salicylate ototoxicity in the

Development, Translation and Validation of Enhanced Asian Rome III Questionnaires for Diagnosis of Functional Bowel Diseases in Major Asian Languages: A Rome Foundation-Asian Neurogastroenterology and Motility Association Working Team Report.

PubMed

Ghoshal, Uday C; Gwee, Kok-Ann; Chen, Minhu; Gong, Xiao R; Pratap, Nitesh; Hou, Xiaohua; Syam, Ari F; Abdullah, Murdani; Bak, Young-Tae; Choi, Myung-Gyu; Gonlachanvit, Sutep; Chua, Andrew S B; Chong, Kuck-Meng; Siah, Kewin T H; Lu, Ching-Liang; Xiong, Lishou; Whitehead, William E

2015-01-01

The development-processes by regional socio-cultural adaptation of an Enhanced Asian Rome III questionnaire (EAR3Q), a cultural adaptation of the Rome III diagnostic questionnaire (R3DQ), and its translation-validation in Asian languages are presented. As English is not the first language for most Asians, translation-validation of EAR3Q is essential. Hence, we aimed to culturally adapt the R3DQ to develop EAR3Q and linguistically validate it to show that the EAR3Q is able to allocate diagnosis according to Rome III criteria. After EAR3Q was developed by Asian experts by consensus, it was translated into Chinese, Hindi-Telugu, Indonesian, Korean and Thai, following Rome Foundation guidelines; these were then validated on native subjects (healthy [n = 60], and patients with irritable bowel syndrome [n = 59], functional dyspepsia [n = 53] and functional constipation [n = 61]) diagnosed by clinicians using Rome III criteria, negative alarm features and investigations. Experts noted words for constipation, bloating, fullness and heartburn, posed difficulty. The English back-translated questionnaires demonstrated concordance with the original EAR3Q. Sensitivity and specificity of the questionnaires were high enough to diagnose respective functional gastrointestinal disorders (gold standard: clinical diagnoses) in most except Korean and Indonesian languages. Questionnaires often uncovered overlapping functional gastrointestinal disorders. Test-retest agreement (kappa) values of the translated questionnaires were high (0.700-1.000) except in Korean (0.300-0.500) and Indonesian (0.100-0.400) languages at the initial and 2-week follow-up visit. Though Chinese, Hindi and Telugu translations were performed well, Korean and Indonesian versions were not. Questionnaires often uncovered overlapping FGIDs, which were quite common.

Communication routes between intracranial spaces and inner ear: function, pathophysiologic importance and relations with inner ear diseases.

PubMed

Ciuman, Raphael R

2009-01-01

There exist 3 communication routes between the intracranial space and the inner ear, the vestibular aqueduct, the cochlear aqueduct, and the internal auditory canal. They possess a key role in inner ear pressure regulation and fluid homeostasis and are related to inner ear diseases. Relevant literature was reviewed, and the current knowledge of the anatomy, physiologic importance, and relations to inner ear diseases were described. Pathologic communication routes such as semicircular canal dehiscence syndrome were highlighted as well. Abnormalities in all 3 communication routes may predispose or be the cause of distinct inner ear pathologic condition and involved in other cochlear and vestibular syndromes, in which their role is not completely clear. The increasing knowledge of the underlying mechanisms encourages promising approaches for possible intervention in the future.

Thyroid Hormone Receptors Control Developmental Maturation of the Middle Ear and the Size of the Ossicular Bones

PubMed Central

Cordas, Emily A.; Ng, Lily; Hernandez, Arturo; Kaneshige, Masahiro; Cheng, Sheue-Yann

2012-01-01

Thyroid hormone is critical for auditory development and has well-known actions in the inner ear. However, less is known of thyroid hormone functions in the middle ear, which contains the ossicles (malleus, incus, stapes) that relay mechanical sound vibrations from the outer ear to the inner ear. During the later stages of middle ear development, prior to the onset of hearing, middle ear cavitation occurs, involving clearance of mesenchyme from the middle ear cavity while the immature cartilaginous ossicles attain appropriate size and ossify. Using in situ hybridization, we detected expression of Thra and Thrb genes encoding thyroid hormone receptors α1 and β (TRα1 and TRβ, respectively) in the immature ossicles, surrounding mesenchyme and tympanic membrane in the mouse. Thra+/PV mice that express a dominant-negative TRα1 protein exhibited deafness with elevated auditory thresholds and a range of middle ear abnormalities including chronic persistence of mesenchyme in the middle ear into adulthood, markedly enlarged ossicles, and delayed ossification of the ossicles. Congenitally hypothyroid Tshr−/− mice and TR-deficient Thra1−/−;Thrb−/− mice displayed similar abnormalities. These findings demonstrate that middle ear maturation is TR dependent and suggest that the middle ear is a sensitive target for thyroid hormone in development. PMID:22253431

Conditional Deletion of N-Myc Disrupts Neurosensory and Non-sensory Development of the Ear

PubMed Central

Kopecky, Benjamin; Santi, Peter; Johnson, Shane; Schmitz, Heather; Fritzsch, Bernd

2011-01-01

Ear development requires interactions of transcription factors for proliferation and differentiation. The proto-oncogene N-Myc is a member of the Myc family that regulate proliferation. To investigate the function of N-Myc, we conditionally knocked out N-Myc in the ear using Tg(Pax2-Cre) and Foxg 1KiCre. N-Myc CKOs had reduced growth of the ear, abnormal morphology including fused sensory epithelia, disrupted histology, and disorganized neuronal innervation. Using Thin-Sheet Laser Imaging Microscopy (TSLIM), 3D reconstruction and quantification of the cochlea revealed a greater than fifty percent size reduction. Immunochemistry and in situ hybridization showed a gravistatic organ-cochlear fusion and a “circularized” apex with no clear inner and outer hair cells. Furthermore, the abnormally developed cochlea had cross innervation from the vestibular ganglion near the basal tip. These findings are put in the context of the possible functional relationship of N-Myc with a number of other cell proliferative and fate determining genes during ear development. PMID:21448975

Acoustical transmission-line model of the middle-ear cavities and mastoid air cells.

PubMed

Keefe, Douglas H

2015-04-01

An acoustical transmission line model of the middle-ear cavities and mastoid air cell system (MACS) was constructed for the adult human middle ear with normal function. The air-filled cavities comprised the tympanic cavity, aditus, antrum, and MACS. A binary symmetrical airway branching model of the MACS was constructed using an optimization procedure to match the average total volume and surface area of human temporal bones. The acoustical input impedance of the MACS was calculated using a recursive procedure, and used to predict the input impedance of the middle-ear cavities at the location of the tympanic membrane. The model also calculated the ratio of the acoustical pressure in the antrum to the pressure in the middle-ear cavities at the location of the tympanic membrane. The predicted responses were sensitive to the magnitude of the viscothermal losses within the MACS. These predicted input impedance and pressure ratio functions explained the presence of multiple resonances reported in published data, which were not explained by existing MACS models.

Evidence for a Right-Ear Advantage in Newborn Hearing Screening Results.

PubMed

Ari-Even Roth, Daphne; Hildesheimer, Minka; Roziner, Ilan; Henkin, Yael

2016-12-06

The aim of the present study was to investigate the effect of ear asymmetry, order of testing, and gender on transient-evoked otoacoustic emission (TEOAE) pass rates and response levels in newborn hearing screening. The screening results of 879 newborns, of whom 387 (study group) passed screening successfully in only one ear in the first TEOAE screening, but passed screening successfully in both ears thereafter, and 492 (control group) who passed screening successfully in both ears in the first TEOAE, were retrospectively examined for pass rates and TEOAE characteristics. Results indicated a right-ear advantage, as manifested by significantly higher pass rates in the right ear (61% and 39% for right and left ears, respectively) in the study group, and in 1.75 dB greater TEOAE response amplitudes in the control group. The right-ear advantage was enhanced when the first tested ear was the right ear (76%). When the left ear was tested first, pass rates were comparable in both ears. The right-ear advantage in pass rates was similar in females versus males, but manifested in 1.5 dB higher response amplitudes in females compared with males, regardless of the tested ear and order of testing in both study and control groups. The study provides further evidence for the functional lateralization of the auditory system at the cochlear level already apparent soon after birth in both males and females. While order of testing plays a significant role in the asymmetry in pass rates, the innate right-ear advantage seems to be a more dominant contributor. © The Author(s) 2016.

Evidence for a Right-Ear Advantage in Newborn Hearing Screening Results

PubMed Central

Hildesheimer, Minka; Roziner, Ilan; Henkin, Yael

2016-01-01

The aim of the present study was to investigate the effect of ear asymmetry, order of testing, and gender on transient-evoked otoacoustic emission (TEOAE) pass rates and response levels in newborn hearing screening. The screening results of 879 newborns, of whom 387 (study group) passed screening successfully in only one ear in the first TEOAE screening, but passed screening successfully in both ears thereafter, and 492 (control group) who passed screening successfully in both ears in the first TEOAE, were retrospectively examined for pass rates and TEOAE characteristics. Results indicated a right-ear advantage, as manifested by significantly higher pass rates in the right ear (61% and 39% for right and left ears, respectively) in the study group, and in 1.75 dB greater TEOAE response amplitudes in the control group. The right-ear advantage was enhanced when the first tested ear was the right ear (76%). When the left ear was tested first, pass rates were comparable in both ears. The right-ear advantage in pass rates was similar in females versus males, but manifested in 1.5 dB higher response amplitudes in females compared with males, regardless of the tested ear and order of testing in both study and control groups. The study provides further evidence for the functional lateralization of the auditory system at the cochlear level already apparent soon after birth in both males and females. While order of testing plays a significant role in the asymmetry in pass rates, the innate right-ear advantage seems to be a more dominant contributor. PMID:27927982

Ototoxicity of boric acid powder in a rat animal model.

PubMed

Salihoglu, Murat; Dogru, Salim; Cesmeci, Enver; Caliskan, Halil; Kurt, Onuralp; Kuçukodaci, Zafer; Gungor, Atila

2017-04-22

Boric acid, which has antiseptic and acidic properties, is used to treat external and middle ear infections. However, we have not found any literature about the effect of boric acid powder on middle ear mucosa and inner ear. The purpose of this study is to investigate possible ototoxic effects of boric acid powder (BAP) on cochlear outer hair cell function and histological changes in middle ear mucosa in a rat animal model. Twenty healthy, mature Wistar albino rats were used in this study. The rats were divided into two groups, Group A and Group B, each of which consisted of 10 rats. Initially, the animals in each group underwent distortion product otoacoustic emissions (DPOAE) testing of their right and left ears. After the first DPOAE test, a surgical microscope was used to make a small perforation in both ears of the rats in each group, and a second DPOAE test was used to measure both ears in all of the rats. BAP was applied to the right middle ear of the rats using tympanic membrane perforation, and the DPOAEs were measured immediately after the BAP application. The histological changes and DPOAEs were evaluated three days later in Group A and 40 days later in Group B. No significant differences were found at all of the DPOAE frequencies. In Group A, mild inflammation of the middle ear mucosa was found on the third day after BAP application. In Group B, BAP caused mild inflammatory changes on the 40th day, which declined over time. Those changes did not lead to significant fibrosis within the mucosa. In rats, BAP causes mild inflammation in middle ear mucosa and it has no ototoxic effects on cochlear outer hair cell function in the inner ear of rats. Copyright © 2017 Associação Brasileira de Otorrinolaringologia e Cirurgia Cérvico-Facial. Published by Elsevier Editora Ltda. All rights reserved.

Modeling Analysis of Biomechanical Changes of Middle Ear and Cochlea in Otitis Media

NASA Astrophysics Data System (ADS)

Gan, Rong Z.; Zhang, Xiangming; Guan, Xiying

2011-11-01

A comprehensive finite element (FE) model of the human ear including the ear canal, middle ear, and spiral cochlea was developed using histological sections of human temporal bone. The cochlea was modeled with three chambers separated by the basilar membrane and Reissner's membrane and filled with perilymphatic fluid. The viscoelastic material behavior was applied to middle ear soft tissues based on dynamic measurements of tissues in our lab. The model was validated using the experimental data obtained in human temporal bones and then used to simulate various stages of otitis media (OM) including the changes of morphology, mechanical properties, pressure, and fluid level in the middle ear. Function alterations of the middle ear and cochlea in OM were derived from the model and compared with the measurements from temporal bones. This study indicates that OM can be simulated in the FE model to predict the hearing loss induced by biomechanical changes of the middle ear and cochlea.

Ear-Canal Reflectance, Umbo Velocity and Tympanometry in Normal Hearing Adults

PubMed Central

Rosowski, John J; Nakajima, Hideko H.; Hamade, Mohamad A.; Mafoud, Lorice; Merchant, Gabrielle R.; Halpin, Christopher F.; Merchant, Saumil N.

2011-01-01

Objective This study compares measurements of ear-canal reflectance (ECR) to other objective measurements of middle-ear function including, audiometry, umbo velocity (VU), and tympanometry in a population of strictly defined normal hearing ears. Design Data were prospectively gathered from 58 ears of 29 normal hearing subjects, 16 female and 13 male, aged 22–64 years. Subjects met all of the following criteria to be considered as having normal hearing. (1) No history of significant middle-ear disease. (2) No history of otologic surgery. (3) Normal tympanic membrane (TM) on otoscopy. (4) Pure-tone audiometric thresholds of 20 dB HL or better for 0.25 – 8 kHz. (5) Air-bone gaps no greater than 15 dB at 0.25 kHz and 10 dB for 0.5 – 4 kHz. (6) Normal, type-A peaked tympanograms. (7) All subjects had two “normal” ears (as defined by these criteria). Measurements included pure-tone audiometry for 0.25 – 8 kHz, standard 226 Hz tympanometry, Ear canal reflectance(ECR) for 0.2 – 6 kHz at 60 dB SPL using the Mimosa Acoustics HearID system, and Umbo Velocity (VU ) for 0.3 – 6 kHz at 70–90 dB SPL using the HLV-1000 laser Doppler vibrometer (Polytec Inc). Results Mean power reflectance (|ECR|2) was near 1.0 at 0.2– 0.3 kHz, decreased to a broad minimum of 0.3 to 0.4 between 1 and 4 kHz, and then sharply increased to almost 0.8 by 6 kHz. The mean pressure reflectance phase angle (∠ECR) plotted on a linear frequency scale showed a group delay of approximately 0.1 ms for 0.2 – 6 kHz. Small significant differences were observed in |ECR|2 at the lowest frequencies between right and left ears, and between males and females at 4 kHz. |ECR|2 decreased with age, but reached significance only at 1 kHz. Our ECR measurements were generally similar to previous published reports. Highly significant negative correlations were found between |ECR|2 and VU for frequencies below 1 kHz. Significant correlations were also found between the tympanometrically determined peak total compliance and |ECR|2 and The results suggest that middle-ear compliance VU at frequencies below 1 kHz. contributes significantly to the measured power reflectance and umbo velocity at frequencies below 1 kHz, but not at higher frequencies. Conclusions This study has established a database of objective measurements of middle ear function (ear-canal reflectance, umbo velocity, tympanometry) in a population of strictly defined normal hearing ears. The data will promote our understanding of normal middle ear function, and will serve as a control for comparison to similar measurements made in pathological ears. PMID:21857517

New HRCT-based measurement of the human outer ear canal as a basis for acoustical methods.

PubMed

Grewe, Johanna; Thiele, Cornelia; Mojallal, Hamidreza; Raab, Peter; Sankowsky-Rothe, Tobias; Lenarz, Thomas; Blau, Matthias; Teschner, Magnus

2013-06-01

As the form and size of the external auditory canal determine its transmitting function and hence the sound pressure in front of the eardrum, it is important to understand its anatomy in order to develop, optimize, and compare acoustical methods. High-resolution computed tomography (HRCT) data were measured retrospectively for 100 patients who had received a cochlear implant. In order to visualize the anatomy of the auditory canal, its length, radius, and the angle at which it runs were determined for the patients’ right and left ears. The canal’s volume was calculated, and a radius function was created. The determined length of the auditory canal averaged 23.6 mm for the right ear and 23.5 mm for the left ear. The calculated auditory canal volume (Vtotal) was 0.7 ml for the right ear and 0.69 ml for the left ear. The auditory canal was found to be significantly longer in men than in women, and the volume greater. The values obtained can be employed to develop a method that represents the shape of the auditory canal as accurately as possible to allow the best possible outcomes for hearing aid fitting.

Listening to Nature's orchestra with peculiar ears

NASA Astrophysics Data System (ADS)

Yager, David D.

2003-04-01

Insects use hearing for the crucial tasks of communicating with conspecifics and avoiding predators. Although all are based on the same acoustic principles, the diversity of insect ears is staggering and instructive. For instance, a South African grasshopper demonstrates that hearing conspecific calls is possible over distances 1 km with ears that do not have tympana. Actually, these creatures have six pairs of ears that play different roles in behavior. In numerical contrast, praying mantises have just a single ear in the ventral midline. The ear is very effective at detecting ultrasonic bat cries. However, the bioacoustics of sound transduction by two tympana facing each other in a deep, narrow slit is a puzzle. Tachinid flies demonstrate that directional hearing at 5 kHz is possible with a pair of ears fused together to give a total size of 1 mm. The ears are under the fly's chin. Hawk moths have their ears built into their mouthparts and the tympanum is more like a hollow ball than the usual membrane. As an apt last example, cicada ears are actually part of the orchestra: their tympana function both in sound reception and sound production.

Structure and function of the mammalian middle ear. I: Large middle ears in small desert mammals.

PubMed

Mason, Matthew J

2016-02-01

Many species of small desert mammals are known to have expanded auditory bullae. The ears of gerbils and heteromyids have been well described, but much less is known about the middle ear anatomy of other desert mammals. In this study, the middle ears of three gerbils (Meriones, Desmodillus and Gerbillurus), two jerboas (Jaculus) and two sengis (elephant-shrews: Macroscelides and Elephantulus) were examined and compared, using micro-computed tomography and light microscopy. Middle ear cavity expansion has occurred in members of all three groups, apparently in association with an essentially 'freely mobile' ossicular morphology and the development of bony tubes for the middle ear arteries. Cavity expansion can occur in different ways, resulting in different subcavity patterns even between different species of gerbils. Having enlarged middle ear cavities aids low-frequency audition, and several adaptive advantages of low-frequency hearing to small desert mammals have been proposed. However, while Macroscelides was found here to have middle ear cavities so large that together they exceed brain volume, the bullae of Elephantulus are considerably smaller. Why middle ear cavities are enlarged in some desert species but not others remains unclear, but it may relate to microhabitat. © 2015 Anatomical Society.

The measurement of Eustachian tube function in a hyperbaric chamber using an ear canal microphone.

PubMed

Fischer, Hans-Georg; Koch, Andreas; Kähler, Wataru; Pohl, Michael; Pau, Hans-Wilhelm; Zehlicke, Thorsten

2016-03-01

The purpose of this study was to further the understanding of the opening of the Eustachian tube in relation to changes in barometric pressure. An ear canal microphone was used to measure the specific sounds related to tube opening and possible eardrum movements. Five subjects with normal tube function were examined in a hyperbaric chamber (up to 304 kPa). All active and passive equalization events were recorded and correlated with the subjectively perceived pressure regulation in the measured ear. The signals recorded were clear and reproducible. The acoustic analysis distinguished between the different kinds of equalization. Subjective impressions were confirmed by the recorded frequency of acoustic phenomena (clicks). During compression, the sequence of active equalization manoeuvres was in a more regular and steady pattern than during decompression, when the click sounds varied. The study established a simple technical method for analyzing the function of the Eustachian tube and provided new information about barometric pressure regulation of the middle ear.

Inner-ear sound pressures near the base of the cochlea in chinchilla: Further investigation

PubMed Central

Ravicz, Michael E.; Rosowski, John J.

2013-01-01

The middle-ear pressure gain GMEP, the ratio of sound pressure in the cochlear vestibule PV to sound pressure at the tympanic membrane PTM, is a descriptor of middle-ear sound transfer and the cochlear input for a given stimulus in the ear canal. GMEP and the cochlear partition differential pressure near the cochlear base ΔPCP, which determines the stimulus for cochlear partition motion and has been linked to hearing ability, were computed from simultaneous measurements of PV, PTM, and the sound pressure in scala tympani near the round window PST in chinchilla. GMEP magnitude was approximately 30 dB between 0.1 and 10 kHz and decreased sharply above 20 kHz, which is not consistent with an ideal transformer or a lossless transmission line. The GMEP phase was consistent with a roughly 50-μs delay between PV and PTM. GMEP was little affected by the inner-ear modifications necessary to measure PST. GMEP is a good predictor of ΔPCP at low and moderate frequencies where PV ⪢ PST but overestimates ΔPCP above a few kilohertz where PV ≈ PST. The ratio of PST to PV provides insight into the distribution of sound pressure within the cochlear scalae. PMID:23556590

The Effects of Age at Cleft Palate Repair on Middle Ear Function and Hearing Level.

PubMed

Lou, Qun; Zhu, Hongping; Luo, Yi; Zhou, Zhibo; Ma, Lian; Ma, Xiaoran; Fu, Yuan

2018-05-01

To investigate the age effects of cleft palate repair on middle ear function and hearing level in patients who underwent cleft palate repair at different ages by audiologic examination. Medical histories were gathered in detail, and audiologic tests (ie, tympanometry and pure tone hearing threshold) were conducted in 126 patients after palatoplasty. The patients were divided into the following 4 groups according to their ages when they underwent cleft palate repair: group I (0-3 years, 73 patients), group II (4-7 years, 29 patients), group III (8-11 years, 16 patients), and group IV (12 years and older, 8 patients). The data regarding tympanograms, hearing levels, and the average hearing thresholds of each group were analyzed using chi-square tests. The prevalence of middle ear dysfunction and hearing loss in the patients who underwent palatoplasty before 3 years old (27.4% and 2.0% respectively) was significantly lower than that in patients who underwent palatopalsty at 12 years or older (75.0% and 43.7%, respectively). Linear-by-linear association revealed that the prevalences of middle ear dysfunction and hearing loss among the 4 groups were significantly different ( P < .05). The prevalence of middle ear dysfunction and hearing loss tended to increase with advancing age at the time of cleft palate repair. From an audiologist's perspective, palatoplasty at an early age is very beneficial in helping children with cleft palates acquire better middle ear function and hearing level.

Surgical management of 2 different presentations of ear canal atresia in dogs

PubMed Central

Béraud, Romain

2012-01-01

A 6-year-old French spaniel and a 14-month-old German shepherd dog were diagnosed with ear canal atresia. Based on presentation, computed tomography, and auditory function evaluation, the first dog underwent excision of the horizontal ear canal and bulla curettage, and the second underwent re-anastomosis of the vertical canal to the external meatus. Both dogs had successful outcomes. PMID:23024390

15 CFR 772.1 - Definitions of terms as used in the Export Administration Regulations (EAR).

Code of Federal Regulations, 2010 CFR

2010-01-01

..., but not a physical change in wiring or interconnections. Digital transfer rate. (Cat 5)—The total bit...) means an electronic control system for gas turbine or combined cycle engines utilizing a digital...

[Effects of acute infrasound exposure on vestibular and auditory functions and the ultrastructural changes of inner ear in the guinea pig].

PubMed

Feng, B; Jiang, S; Yang, W; Han, D; Zhang, S

2001-02-01

To define the effects of acute infrasound exposure on vestibular and auditory functions and the ultrastructural changes of inner ear in guinea pigs. The animals involved in the study were exposed to 8 Hz infrasound at 135dB SPL for 90 minutes in a reverberant chamber. The sinusoidal pendular test (SPT), auditory brainstem response (ABR) and distortion product otoacoustic emissions (DPOAE) were respectively detected pre-exposure and at 0(within 2 hrs), 2 and 5 day after exposure. The ultrastructures of the inner ear were observed by scanning electron microscopy. The slow-phase velocity and the frequency of the vestibular nystagmus elicited by sinusoidal pendular test (SPT) declined slightly following infrasound exposure, but the changes were not significant (P > 0.05). No differences in the ABR thresholds, the latencies and the interval peak latencies of I, III, V waves were found between the normal and the experimental groups, and among experimental groups. The amplitudes of DPOAE at any frequency declined remarkably in all experimental groups. The ultrastructures of the inner ear were damaged to different extent. Infrasound could transiently depress the excitability of the vestibular end-organs, decrease the function of OHC in the organ of Corti and cause damage to the inner ear of guinea pigs.

Fluid dynamics vascular theory of brain and inner-ear function in traumatic brain injury: a translational hypothesis for diagnosis and treatment.

PubMed

Shulman, Abraham; Strashun, Arnold M

2009-01-01

It is hypothesized that in all traumatic brain injury (TBI) patients with a clinical history of closed or penetrating head injury, the initial head trauma is associated with a vibratory sensation and noise exposure, with resultant alteration in vascular supply to the structures and contents of the fluid compartments of brain and ear (i.e., the fluid dynamics vascular theory of brain-inner-ear function [FDVTBE]). The primary etiology-head trauma-results in an initial fluctuation, interference, or interaction in the normal fluid dynamics between brain and labyrinth of the inner ear, with a resultant clinical diversity of complaints varying in time of onset and severity. Normal function of the brain and ear is a reflection of a normal state of homeostasis between the fluid compartments in the brain of cerebrospinal fluid and perilymph-endolymph in the labyrinth of the ear. The normal homeostasis in the structures and contents between the two fluid compartment systems--intracerebral and intralabyrinthine--is controlled by mechanisms involved in the maintenance of normal pressures, water and electrolyte content, and neurotransmitter activities. The initial pathophysiology (a reflection of an alteration in the vascular supply to the brain-ear) is hypothesized to be an initial acute inflammatory response, persistence of which results in ischemia and an irreversible alteration in the involved neural substrates of brain-ear. Clinically, a chronic multisymptom complex becomes manifest. The multisymptom complex, individual for each TBI patient regardless of the diagnostic TBI category (i.e., mild, moderate, or severe), initially reflects processes of inflammation and ischemia which, in brain, result in brain volume loss identified as neurodegeneration and hydrocephalus ex vacuo or an alteration in cerebrospinal fluid production (i.e., pseudotumor cerebri) and, in ear, secondary endolymphatic hydrops with associated cochleovestibular complaints of hearing loss, tinnitus, vertigo, ear blockage, and hyperacusis. The FDVTBE integrates and translates a neurovascular hypothesis for Alzheimer's disease to TBI. This study presents an FDVTBE hypothesis of TBI to explain the clinical association of head trauma (TBI) and central nervous system neurodegeneration with multisensory complaints, highlighted by and focusing on cochleovestibular complaints. A clinical case report, previously published for demonstration of the cerebrovascular medical significance of a particular type of tinnitus, and evidence-based basic science and clinical medicine are cited to provide objective evidence in support and demonstration of the FDVTBE.

In vitro activity of an ear rinse containing tromethamine, EDTA, benzyl alcohol and 0.1% ketoconazole on Malassezia organisms from dogs with otitis externa.

PubMed

Cole, Lynette K; Luu, Dao H; Rajala-Schultz, Paivi J; Meadows, Cheyney; Torres, Audrey H

2007-04-01

The purpose of this study was to evaluate the in vitro activity of an ear rinse containing tromethamine, EDTA, benzyl alcohol and 0.1% ketoconazole in purified water on Malassezia organisms from dogs with otitis externa. Malassezia organisms were collected from ear swab samples from the external ear canal of 19 dogs with otitis externa plus one control strain of Malassezia pachydermatis. Three test solutions were evaluated: ER (EDTA, tromethamine, benzyl alcohol), ER + keto (EDTA, tromethamine, benzyl alcohol, ketoconazole), and H2O (purified water). Ten-millilitre aliquots of each test solution was transferred into 20 tubes and inoculated with one of the isolates (1 tube per isolate: 19 clinical and 1 control strain). Samples were retrieved from each tube at five time points (0, 15, 30, 45 and 60 min), transferred to Petri dishes, mixed with Sabouraud dextrose agar supplemented with 0.5% Tween 80 and incubated. Following incubation, the plates were examined for growth and colonies counted as colony-forming units per millilitre. The data were analysed using a repeated measures analysis, with pair-wise comparisons of solution-time combinations. There was a significant reduction in Malassezia growth in ER + keto at all time points (P < 0.0001) compared to time zero. Neither ER nor H2O had any effect on the growth of Malassezia. ER + keto was significantly more effective in reducing Malassezia growth (P < 0.0001) at all time points compared to both ER and H2O. ER + keto may be useful in the treatment of Malassezia otitis externa. Future studies should be performed to evaluate the in vivo efficacy of ER + keto as treatment for otic infections caused by Malassezia.

Evolution of the rodent eosinophil-associated RNase gene family by rapid gene sorting and positive selection

PubMed Central

Zhang, Jianzhi; Dyer, Kimberly D.; Rosenberg, Helene F.

2000-01-01

The mammalian RNase A superfamily comprises a diverse array of ribonucleolytic proteins that have a variety of biochemical activities and physiological functions. Two rapidly evolving RNases of higher primates are of particular interest as they are major secretory proteins of eosinophilic leukocytes and have been found to possess anti-pathogen activities in vitro. To understand how these RNases acquired this function during evolution and to develop animal models for the study of their functions in vivo, it is necessary to investigate these genes in many species. Here, we report the sequences of 38 functional genes and 23 pseudogenes of the eosinophil-associated RNase (EAR) family from 5 rodent species. Our phylogenetic analysis of these genes showed a clear pattern of evolution by a rapid birth-and-death process and gene sorting, a process characterized by rapid gene duplication and deactivation occurring differentially among lineages. This process ultimately generates distinct or only partially overlapping inventories of the genes, even in closely related species. Positive Darwinian selection also contributed to the diversification of these EAR genes. The striking similarity between the evolutionary patterns of the EAR genes and those of the major histocompatibility complex, immunoglobulin, and T cell receptor genes stands in strong support of the hypothesis that host-defense and generation of diversity are among the primary physiological function of the rodent EARs. The discovery of a large number of divergent EARs suggests the intriguing possibility that these proteins have been specifically tailored to fight against distinct rodent pathogens. PMID:10758160

Chirp-Evoked Otoacoustic Emissions and Middle Ear Absorbance for Monitoring Ototoxicity in Cystic Fibrosis Patients.

PubMed

Garinis, Angela C; Keefe, Douglas H; Hunter, Lisa L; Fitzpatrick, Denis F; Putterman, Daniel B; McMillan, Garnett P; Gold, Jeffrey A; Feeney, M Patrick

The goal of this study was to investigate the use of transient-evoked otoacoustic emissions (TEOAEs) and middle ear absorbance measurements to monitor auditory function in patients with cystic fibrosis (CF) receiving ototoxic medications. TEOAEs were elicited with a chirp stimulus using an extended bandwidth (0.71 to 8 kHz) to measure cochlear function at higher frequencies than traditional TEOAEs. Absorbance over a wide bandwidth (0.25 to 8 kHz) provides information on middle ear function. The combination of these time-efficient measurements has the potential to identify early signs of ototoxic hearing loss. A longitudinal study design was used to monitor the hearing of 91 patients with CF (median age = 25 years; age range = 15 to 63 years) who received known ototoxic medications (e.g., tobramycin) to prevent or treat bacterial lung infections. Results were compared to 37 normally hearing young adults (median age = 32.5 years; age range = 18 to 65 years) without a history of CF or similar treatments. Clinical testing included 226-Hz tympanometry, pure-tone air-conduction threshold testing from 0.25 to 16 kHz and bone conduction from 0.25 to 4 kHz. Experimental testing included wideband absorbance at ambient and tympanometric peak pressure and TEOAEs in three stimulus conditions: at ambient pressure and at tympanometric peak pressure using a chirp stimulus with constant incident pressure level across frequency and at ambient pressure using a chirp stimulus with constant absorbed sound power across frequency. At the initial visit, behavioral audiometric results indicated that 76 of the 157 ears (48%) from patients with CF had normal hearing, whereas 81 of these ears (52%) had sensorineural hearing loss for at least one frequency. Seven ears from four patients had a confirmed behavioral change in hearing threshold for ≥3 visits during study participation. Receiver operating characteristic curve analyses demonstrated that all three TEOAE conditions were useful for distinguishing CF ears with normal hearing from ears with sensorineural hearing loss, with an area under the receiver operating characteristic curve values ranging from 0.78 to 0.92 across methods for frequency bands from 2.8 to 8 kHz. Case studies are presented to illustrate the relationship between changes in audiometric thresholds, TEOAEs, and absorbance across study visits. Absorbance measures permitted identification of potential middle ear dysfunction at 5.7 kHz in an ear that exhibited a temporary hearing loss. The joint use of TEOAEs and absorbance has the potential to explain fluctuations in audiometric thresholds due to changes in cochlear function, middle ear function, or both. These findings are encouraging for the joint use of TEOAE and wideband absorbance objective tests for monitoring ototoxicity, particularly, in patients who may be too ill for behavioral hearing tests. Additional longitudinal studies are needed in a larger number of CF patients receiving ototoxic drugs to further evaluate the clinical utility of these measures in an ototoxic monitoring program.

Selective forces on origin, adaptation and reduction of tympanal ears in insects.

PubMed

Strauß, Johannes; Stumpner, Andreas

2015-01-01

Insect ears evolved many times independently. As a consequence, a striking diversity exists in the location, construction and behavioural implementation of ears. In this review, we first summarise what is known about the evolutionary origin of ears and the presumed precursor organs in the various insect groups. Thereafter, we focus on selective forces for making and keeping an ear: we discuss detecting and localising predators and conspecifics, including establishing new "private" channels for intraspecific communication. More advanced aspects involve judging the distance of conspecifics, or assessing individual quality from songs which makes auditory processing a means for exerting sexual selection on mating partners. We try to identify negative selective forces, mainly in the context of energy expenditure for developing and keeping an ear, but also in conjunction with acoustic communication, which incorporates risks like eavesdropping by predators and parasitoids. We then discuss balancing pressures, which might oppose optimising an ear for a specific task (when it serves different functions, for example). Subsequently, we describe various scenarios that might have led to a reduction or complete loss of ears in evolution. Finally, we describe cases of sex differences in ears and potential reasons for their appearance.

The relationships between cognitive function and hearing loss among the elderly.

PubMed

Huh, MyungJin

2018-01-01

[Purpose] Research related to dementia has gained momentum in South Korea and studies have found that the auditory sense affects dementia. This study aims to examine the relationship between the decline in hearing function and the overall cognitive function among the elderly. [Subjects and Methods] Eighty-two older adults aged 65-90 years (mean age: 79.3, SD: 5.2) participated. The Korean Mini-Mental State Examination was used to assess cognitive function. Further, to assess the hearing function, pure-tone audiometry was performed prior to the cognitive function test. We used a paired t-test and Pearson's correlation test for the analysis. [Results] Generally, the higher the frequency band, the more hearing loss was identified among the elderly. In addition, the difference in hearing between both ears was significant; particularly, hearing loss in the right ear was significantly higher than that in the left. Cognitive function was not related to age, however, the correlation between cognitive function and hearing loss in the right ear was statistically significant. [Conclusion] Hearing loss influences cognitive function among the elderly.

Development, Translation and Validation of Enhanced Asian Rome III Questionnaires for Diagnosis of Functional Bowel Diseases in Major Asian Languages: A Rome Foundation-Asian Neurogastroenterology and Motility Association Working Team Report

PubMed Central

Ghoshal, Uday C; Gwee, Kok-Ann; Chen, Minhu; Gong, Xiao R; Pratap, Nitesh; Hou, Xiaohua; Syam, Ari F; Abdullah, Murdani; Bak, Young-Tae; Choi, Myung-Gyu; Gonlachanvit, Sutep; Chua, Andrew S B; Chong, Kuck-Meng; Siah, Kewin T H; Lu, Ching-Liang; Xiong, Lishou; Whitehead, William E

2015-01-01

Background/Aims The development-processes by regional socio-cultural adaptation of an Enhanced Asian Rome III questionnaire (EAR3Q), a cultural adaptation of the Rome III diagnostic questionnaire (R3DQ), and its translation-validation in Asian languages are presented. As English is not the first language for most Asians, translation-validation of EAR3Q is essential. Hence, we aimed to culturally adapt the R3DQ to develop EAR3Q and linguistically validate it to show that the EAR3Q is able to allocate diagnosis according to Rome III criteria. Methods After EAR3Q was developed by Asian experts by consensus, it was translated into Chinese, Hindi-Telugu, Indonesian, Korean, and Thai, following Rome Foundation guidelines; these were then validated on native subjects (healthy [n = 60], and patients with irritable bowel syndrome [n = 59], functional dyspepsia [n = 53] and functional constipation [n = 61]) diagnosed by clinicians using Rome III criteria, negative alarm features and investigations. Results Experts noted words for constipation, bloating, fullness and heartburn, posed difficulty. The English back-translated questionnaires demonstrated concordance with the original EAR3Q. Sensitivity and specificity of the questionnaires were high enough to diagnose respective functional gastrointestinal disorders (gold standard: clinical diagnoses) in most except Korean and Indonesian languages. Questionnaires often uncovered overlapping functional gastrointestinal disorders. Test-retest agreement (kappa) values of the translated questionnaires were high (0.700–1.000) except in Korean (0.300–0.500) and Indonesian (0.100–0.400) languages at the initial and 2-week follow-up visit. Conclusions Though Chinese, Hindi and Telugu translations were performed well, Korean and Indonesian versions were not. Questionnaires often uncovered overlapping FGIDs, which were quite common. PMID:25537673

A New Intraoperative Real-time Monitoring System for Reconstructive Middle Ear Surgery: An Experimental and Clinical Feasibility Study.

PubMed

Zahnert, Thomas; Metasch, Marie-Luise; Seidler, Hannes; Bornitz, Matthias; Lasurashvili, Nicoloz; Neudert, Marcus

2016-12-01

Electromagnetical excitation of ossicular vibration is suitable for middle ear transmission measurements in the experimental and clinical setting. Thereby, it can be used as a real-time monitoring system for quality control in ossiculoplasty. Positioning and coupling of middle ear prosthesis are a precondition for good postoperative hearing results, but at the same time completely dependent upon the surgeon's subjective judgment during surgery. We evaluated an electromagnetically driven measurement system that enables for in vitro and in vivo transmission measurements and thus can be used as a real-time monitoring tool in ossicular reconstruction. For electromagnetical excitation a magnet was placed on the umbo of the malleus handle and driven by a magnetic field. The induced stapes displacement was picked up by laser Doppler vibrometry on the footplate. Measurements were performed on the intact ossicular chain in five cadaveric temporal bones and during five cochlear implant surgeries. Additionally, two ossiculoplasties were performed under real-time transmission feedback with the monitoring system. Experimentally, the equivalent sound pressure level of the electromagnetic excitation was about 70 to 80 dB which is 10 to 20 dB less than the acoustic stimulation. In the intraoperative setup the generated stapes displacements were about 5 to 20 dB smaller compared with the temporal bone experiments. Applied as real-time feedback system, an improvement in the middle ear transfer function of 4.5 dB in total and 20 dB in partial ossicular reconstruction were achieved. The electromagnetical excitation and measurement system is comparable to the gold standard with acoustical stimulation in both, the experimental setup in temporal bones as well as in vivo. The technical feasibility of the electromagnetical excitation method has been proven and it is shown that it can be used as a real-time monitoring system for ossiculoplasty in the operation room.

Dietary exposure of BDE-47 and BDE-99 and effects on behavior, bioenergetics, and thyroid function in juvenile red-eared sliders (Trachemys scripta elegans) and common snapping turtles (Chelydra serpentina).

PubMed

Eisenreich, Karen M; Rowe, Christopher L

2014-12-01

Juvenile red-eared sliders (Trachemys scripta elegans) and snapping turtles (Chelydra serpentina) were fed food dosed with brominated diphenyl ether-47 (BDE-47) or BDE-99 for 6 mo beginning approximately 9 mo posthatch. During the exposure period, measurements of growth, bioenergetics, and behavior were made; thyroid function and accumulation were quantified postexposure. Whole-body concentrations of both congeners were lower in red-eared sliders compared with snapping turtles after 6 mo of exposure. Snapping turtles receiving BDE-47 had significantly elevated standard metabolic rates after 3 mo and 4 mo of exposure (p = 0.014 and p = 0.019, respectively). When exposed to BDE-99, red-eared sliders were slower to right themselves after having been inverted (p < 0.0001). Total glandular thyroxine concentrations were significantly reduced in red-eared sliders exposed to BDE-47 (mean control, 8080 ng/g; mean BDE-47, 5126 ng/g; p = 0.034). These results demonstrate that dietary exposure to BDE-47 and BDE-99 can elicit a suite of responses in 2 species of turtles, but that the red-eared slider appears to be a more sensitive species to the measured end points. © 2014 SETAC.

Probe-tube microphone measures in hearing-impaired children and adults.

PubMed

Barlow, N L; Auslander, M C; Rines, D; Stelmachowicz, P G

1988-10-01

This study was designed to investigate the reliability of real-ear measurements of sound pressure level (SPL) and to compare these values with two coupler measures of SPL. A commercially available probe tube microphone system was used to measure real ear SPL in both children and adults. Test-retest reliability decreased as a function of frequency for both groups and, in general, was slightly poorer for the children. For both groups, coupler to real ear differences were larger for the 2 cm3 coupler than for the reduced volume coupler; however, no significant differences were observed between groups. In addition, a measure of ear canal volume was not found to be a good predictor of coupler to real ear discrepancies.

Concise Review: Inner Ear Stem Cells—An Oxymoron, But Why?

PubMed Central

Ronaghi, Mohammad; Nasr, Marjan; Heller, Stefan

2012-01-01

Hearing loss, caused by irreversible loss of cochlear sensory hair cells, affects millions of patients worldwide. In this concise review, we examine the conundrum of inner ear stem cells, which obviously are present in the inner ear sensory epithelia of nonmammalian vertebrates, giving these ears the ability to functionally recover even from repetitive ototoxic insults. Despite the inability of the mammalian inner ear to regenerate lost hair cells, there is evidence for cells with regenerative capacity because stem cells can be isolated from vestibular sensory epithelia and from the neonatal cochlea. Challenges and recent progress toward identification of the intrinsic and extrinsic signaling pathways that could be used to re-establish stemness in the mammalian organ of Corti are discussed. PMID:22102534

Effect of Evolutionary Anisotropy on Earing Prediction in Cylindrical Cup Drawing

NASA Astrophysics Data System (ADS)

Choi, H. J.; Lee, K. J.; Choi, Y.; Bae, G.; Ahn, D.-C.; Lee, M.-G.

2017-05-01

The formability of sheet metals is associated with their planar anisotropy, and finite element simulations have been applied to the sheet metal-forming process by describing the anisotropic behaviors using yield functions and hardening models. In this study, the evaluation of anisotropic constitutive models was performed based on the non-uniform height profile or earing in circular cylindrical cup drawing. Two yield functions, a quadratic Hill1948 and a non-quadratic Yld2000-2d model, were used under non-associated and associated flow rules, respectively, to simultaneously capture directional differences in yield stress and r value. The effect of the evolution of anisotropy on the earing prediction was also investigated by employing simplified equivalent plastic strain rate-dependent anisotropic coefficients. The computational results were in good agreement with experiments when the proper choice of the yield function and flow rule, which predicts the planar anisotropy, was made. Moreover, the accuracy of the earing profile could be significantly enhanced if the evolution of anisotropy between uniaxial and biaxial stress states was additionally considered.

Sensitivity and Specificity of Eustachian Tube Function Tests in Adults

PubMed Central

Doyle, William J.; Swarts, J. Douglas; Banks, Julianne; Casselbrant, Margaretha L; Mandel, Ellen M; Alper, Cuneyt M.

2013-01-01

Objective Determine if Eustachian Tube (ET) function (ETF) tests can identify ears with physician-diagnosed ET dysfunction (ETD) in a mixed population at high sensitivity and specificity and define the inter-relatedness of ETF test parameters. Methods ETF was evaluated using the Forced-Response, Inflation-Deflation, Valsalva and Sniffing tests in 15 control ears of adult subjects after unilateral myringotomy (Group I) and in 23 ears of 19 adult subjects with ventilation tubes inserted for ETD (Group II). Data were analyzed using logistic regression including each parameter independently and then a step-down Discriminant Analysis including all ETF test parameters to predict group assignment. Factor Analysis operating over all parameters was used to explore relatedness. Results The Discriminant Analysis identified 4 ETF test parameters (Valsalva, ET opening pressure, dilatory efficiency and % positive pressure equilibrated) that together correctly assigned ears to Group II at a sensitivity of 95% and a specificity of 83%. Individual parameters representing the efficiency of ET opening during swallowing showed moderately accurate assignments of ears to their respective groups. Three factors captured approximately 98% of the variance among parameters, the first had negative loadings of the ETF structural parameters, the second had positive loadings of the muscle-assisted ET opening parameters and the third had negative loadings of the muscle-assisted ET opening parameters and positive loadings of the structural parameters. Discussion These results show that ETF tests can correctly assign individual ears to physician-diagnosed ETD with high sensitivity and specificity and that ETF test parameters can be grouped into structural-functional categories. PMID:23868429

Induction of atopic eczema/dermatitis syndrome-like skin lesions by repeated topical application of a crude extract of Dermatophagoides pteronyssinus in NC/Nga mice.

PubMed

Kang, Jong Soon; Lee, Kiho; Han, Sang-Bae; Ahn, Ji-Mi; Lee, Hyunju; Han, Mi Hwa; Yoon, Yeo Dae; Yoon, Won Kee; Park, Song-Kyu; Kim, Hwan Mook

2006-10-01

Mite antigen has been considered to play important roles in the development of atopic eczema/dermatitis syndrome (AEDS). In the present study, we attempted to induce an AEDS-like skin lesion in mice using Dermatophagoides pteronyssinus crude extract (DPE) as an antigen and performed pathophysiological evaluations. Ears of mice were tape-stripped and DPE was painted 3 times a week. Eczematous skin lesion and ear swelling were apparent in NC/Nga mice treated with DPE after 2 weeks, whereas neither skin lesion nor ear swelling were observed in BALB/c mice even after 30 days. Histological evaluation demonstrated that edema, epidermal hyperplasia and the accumulation of inflammatory cells were apparent in the ears of DPE-treated NC/Nga mice. In contrast to skin lesion and ear swelling, total serum IgE levels were increased in both NC/Nga and BALB/c mice. Treatment with DPE also increased auricular lymph node weight in both NC/Nga mice and BALB/c mice. To further characterize, we analyzed cytokine mRNA expression in ears and lymph nodes of DPE-treated NC/Nga mice. Increased expression of IL-4 and TNF-alpha mRNA was observed in both ears and lymph nodes of NC/Nga mice treated with DPE. Additionally, there was no change in the responsiveness of BALB/c mice to DPE treatment by adaptive transfer of serum from DPE-treated NC/Nga mice to BALB/c mice. Taken together, our results indicate that eczematous skin lesion and ear swelling caused by repeated application of DPE in NC/Nga mice has a Th2-dominant background and that inflammation is involved in this process. The animal model of AEDS established in this report may be used to investigate the pathogenesis of AEDS and evaluate the potential therapeutic agents for AEDS.

Ick Ciliary Kinase Is Essential for Planar Cell Polarity Formation in Inner Ear Hair Cells and Hearing Function.

PubMed

Okamoto, Shio; Chaya, Taro; Omori, Yoshihiro; Kuwahara, Ryusuke; Kubo, Shun; Sakaguchi, Hirofumi; Furukawa, Takahisa

2017-02-22

Cellular asymmetries play crucial roles in development and organ function. The planar cell polarity (PCP) signaling pathway is involved in the establishment of cellular asymmetry within the plane of a cell sheet. Inner ear sensory hair cells (HCs), which have several rows of staircase-like stereocilia and one kinocilium located at the vertex of the stereocilia protruding from the apical surface of each HC, exhibit a typical form of PCP. Although connections between cilia and PCP signaling in vertebrate development have been reported, their precise nature is not well understood. During inner ear development, several ciliary proteins are known to play a role in PCP formation. In the current study, we investigated a functional role for intestinal cell kinase (Ick), which regulates intraflagellar transport (IFT) at the tip of cilia, in the mouse inner ear. A lack of Ick in the developing inner ear resulted in PCP defects in the cochlea, including misorientation or misshaping of stereocilia and aberrant localization of the kinocilium and basal body in the apical and middle turns, leading to auditory dysfunction. We also observed abnormal ciliary localization of Ift88 in both HCs and supporting cells. Together, our results show that Ick ciliary kinase is essential for PCP formation in inner ear HCs, suggesting that ciliary transport regulation is important for PCP signaling. SIGNIFICANCE STATEMENT The cochlea in the inner ear is the hearing organ. Planar cell polarity (PCP) in hair cells (HCs) in the cochlea is essential for mechanotransduction and refers to the asymmetric structure consisting of stereociliary bundles and the kinocilium on the apical surface of the cell body. We reported previously that a ciliary kinase, Ick, regulates intraflagellar transport (IFT). Here, we found that loss of Ick leads to abnormal localization of the IFT component in kinocilia, PCP defects in HCs, and hearing dysfunction. Our study defines the association of ciliary transport regulation with PCP formation in HCs and hearing function. Copyright © 2017 the authors 0270-6474/17/372073-13$15.00/0.

Middle-Ear Pressure Gain and Cochlear Partition Differential Pressure in Chinchilla

PubMed Central

Ravicz, Michael E.; Slama, Michaël C.C.; Rosowski, John J.

2009-01-01

An important step to describe the effects of inner-ear impedance and pathologies on middle- and inner-ear mechanics is to quantify middle- and inner-ear function in the normal ear. We present middle-ear pressure gain GMEP and trans-cochlear-partition differential sound pressure ΔPCP in chinchilla from 100 Hz to 30 kHz derived from measurements of intracochlear sound pressures in scala vestibuli PSV and scala tympani PST and ear-canal sound pressure near the tympanic membrane PTM. These measurements span the chinchilla's auditory range. GMEP had constant magnitude of about 20 dB between 300 Hz and 20 kHz and phase that implies a 40-μs delay, values with some similarities to previous measurements in chinchilla and other species. ΔPCP was similar to GMEP below about 10 kHz and lower in magnitude at higher frequencies, decreasing to 0 dB at 20 kHz. The high-frequency rolloff correlates with the audiogram and supports the idea that middle-ear transmission limits high-frequency hearing, providing a stronger link between inner-ear macromechanics and hearing. We estimate the cochlear partition impedance ZCP from these and previous data. The chinchilla may be a useful animal model for exploring the effects of nonacoustic inner-ear stimulation such as “bone conduction” on cochlear mechanics. PMID:19945521

In situ tissue engineering with synthetic self-assembling peptide nanofiber scaffolds, PuraMatrix, for mucosal regeneration in the rat middle-ear

PubMed Central

Akiyama, Naotaro; Yamamoto-Fukuda, Tomomi; Takahashi, Haruo; Koji, Takehiko

2013-01-01

Middle-ear mucosa maintains middle-ear pressure. However, the majority of surgical cases exhibit inadequate middle-ear mucosal regeneration, and mucosal transplantation is necessary in such cases. The aim of the present study was to assess the feasibility of transplantation of isolated mucosal cells encapsulated within synthetic self-assembling peptide nanofiber scaffolds using PuraMatrix, which has been successfully used as scaffolding in tissue engineering, for the repair of damaged middle-ear. Middle-ear bullae with mucosa were removed from Sprague Dawley (SD) transgenic rats, transfected with enhanced green fluorescent protein (EGFP) transgene and excised into small pieces, then cultured up to the third passage. After surgical elimination of middle-ear mucosa in SD recipient rats, donor cells were encapsulated within PuraMatrix and transplanted into these immunosuppressed rats. Primary cultured cells were positive for pancytokeratin but not for vimentin, and retained the character of middle-ear epithelial cells. A high proportion of EGFP-expressing cells were found in the recipient middle-ear after transplantation with PuraMatrix, but not without PuraMatrix. These cells retained normal morphology and function, as confirmed by histological examination, immunohistochemistry, and electron microscopy, and multiplied to form new epithelial and subepithelial layers together with basement membrane. The present study demonstrated the feasibility of transplantation of cultured middle-ear mucosal epithelial cells encapsulated within PuraMatrix for regeneration of surgically eliminated mucosa of the middle-ear in SD rats. PMID:23926427

In situ tissue engineering with synthetic self-assembling peptide nanofiber scaffolds, PuraMatrix, for mucosal regeneration in the rat middle-ear.

PubMed

Akiyama, Naotaro; Yamamoto-Fukuda, Tomomi; Takahashi, Haruo; Koji, Takehiko

2013-01-01

Middle-ear mucosa maintains middle-ear pressure. However, the majority of surgical cases exhibit inadequate middle-ear mucosal regeneration, and mucosal transplantation is necessary in such cases. The aim of the present study was to assess the feasibility of transplantation of isolated mucosal cells encapsulated within synthetic self-assembling peptide nanofiber scaffolds using PuraMatrix, which has been successfully used as scaffolding in tissue engineering, for the repair of damaged middle-ear. Middle-ear bullae with mucosa were removed from Sprague Dawley (SD) transgenic rats, transfected with enhanced green fluorescent protein (EGFP) transgene and excised into small pieces, then cultured up to the third passage. After surgical elimination of middle-ear mucosa in SD recipient rats, donor cells were encapsulated within PuraMatrix and transplanted into these immunosuppressed rats. Primary cultured cells were positive for pancytokeratin but not for vimentin, and retained the character of middle-ear epithelial cells. A high proportion of EGFP-expressing cells were found in the recipient middle-ear after transplantation with PuraMatrix, but not without PuraMatrix. These cells retained normal morphology and function, as confirmed by histological examination, immunohistochemistry, and electron microscopy, and multiplied to form new epithelial and subepithelial layers together with basement membrane. The present study demonstrated the feasibility of transplantation of cultured middle-ear mucosal epithelial cells encapsulated within PuraMatrix for regeneration of surgically eliminated mucosa of the middle-ear in SD rats.

Human middle-ear model with compound eardrum and airway branching in mastoid air cells

PubMed Central

Keefe, Douglas H.

2015-01-01

An acoustical/mechanical model of normal adult human middle-ear function is described for forward and reverse transmission. The eardrum model included one component bound along the manubrium and another bound by the tympanic cleft. Eardrum components were coupled by a time-delayed impedance. The acoustics of the middle-ear cleft was represented by an acoustical transmission-line model for the tympanic cavity, aditus, antrum, and mastoid air cell system with variable amounts of excess viscothermal loss. Model parameters were fitted to published measurements of energy reflectance (0.25–13 kHz), equivalent input impedance at the eardrum (0.25–11 kHz), temporal-bone pressure in scala vestibuli and scala tympani (0.1–11 kHz), and reverse middle-ear impedance (0.25–8 kHz). Inner-ear fluid motion included cochlear and physiological third-window pathways. The two-component eardrum with time delay helped fit intracochlear pressure responses. A multi-modal representation of the eardrum and high-frequency modeling of the middle-ear cleft helped fit ear-canal responses. Input reactance at the eardrum was small at high frequencies due to multiple modal resonances. The model predicted the middle-ear efficiency between ear canal and cochlea, and the cochlear pressures at threshold. PMID:25994701

Human middle-ear model with compound eardrum and airway branching in mastoid air cells.

PubMed

Keefe, Douglas H

2015-05-01

An acoustical/mechanical model of normal adult human middle-ear function is described for forward and reverse transmission. The eardrum model included one component bound along the manubrium and another bound by the tympanic cleft. Eardrum components were coupled by a time-delayed impedance. The acoustics of the middle-ear cleft was represented by an acoustical transmission-line model for the tympanic cavity, aditus, antrum, and mastoid air cell system with variable amounts of excess viscothermal loss. Model parameters were fitted to published measurements of energy reflectance (0.25-13 kHz), equivalent input impedance at the eardrum (0.25-11 kHz), temporal-bone pressure in scala vestibuli and scala tympani (0.1-11 kHz), and reverse middle-ear impedance (0.25-8 kHz). Inner-ear fluid motion included cochlear and physiological third-window pathways. The two-component eardrum with time delay helped fit intracochlear pressure responses. A multi-modal representation of the eardrum and high-frequency modeling of the middle-ear cleft helped fit ear-canal responses. Input reactance at the eardrum was small at high frequencies due to multiple modal resonances. The model predicted the middle-ear efficiency between ear canal and cochlea, and the cochlear pressures at threshold.

Morphometry of the ear in Down's syndrome subjects. A three-dimensional computerized assessment.

PubMed

Sforza, C; Dellavia, C; Tartaglia, G M; Ferrario, V F

2005-07-01

The three-dimensional coordinates of 13 soft-tissue landmarks on the ears were obtained by a computerized digitizer in 28 subjects with Down's syndrome aged 12-45 years, and in 449 sex, age and ethnic group matched controls. From the landmarks, left and right linear distances (ear width and length), ratios (ear width-to-ear length), areas (ear area), angles (angle of the auricle versus the facial midplane) and the three-dimensional symmetry index were calculated. For both males and females, all linear dimensions and areas were significantly (Analysis of Variance, P < 0.001) larger in the reference subjects than in the subjects with Down's syndrome. All values significantly increased as a function of age (P < 0.05); the increment was larger in the reference subjects than in the subjects with Down's syndrome. On both sides of the face, the subjects with Down's syndrome had larger ear width-to-ear length ratios, and larger angles of the auricle versus the facial midplane than the reference subjects. The three-dimensional symmetry index was significantly larger in the reference subjects and in the older persons. In conclusion, ear dimensions, position and shape significantly differed in subjects with Down's syndrome when compared to sex, age and ethnic group matched controls. Some of the differences were sex and age related.

Hearing and hearing loss: Causes, effects, and treatments

NASA Astrophysics Data System (ADS)

Schmiedt, Richard A.

2003-04-01

Hearing loss can have multiple causes. The outer and middle ears are conductive pathways for acoustic energy to the inner ear (cochlea) and help shape our spectral sensitivity. Conductive hearing loss is mechanical in nature such that the energy transfer to the cochlea is impeded, often from eardrum perforations or middle ear fluid buildup. Beyond the middle ear, the cochlea comprises three interdependent systems necessary for normal hearing. The first is that of basilar-membrane micromechanics including the outer hair cells. This system forms the basis of the cochlear amplifier and is the most vulnerable to noise and drug exposure. The second system comprises the ion pumps in the lateral wall tissues of the cochlea. These highly metabolic cells provide energy to the cochlear amplifier in the form of electrochemical potentials. This second system is particularly vulnerable to the effects of aging. The third system comprises the inner hair cells and their associated sensory nerve fibers. This system is the transduction stage, changing mechanical vibrations to nerve impulses. New treatments for hearing loss are on the horizon; however, at present the best strategy is avoidance of cochlear trauma and the proper use of hearing aids. [Work supported by NIA and MUSC.

Concise review: Inner ear stem cells--an oxymoron, but why?

PubMed

Ronaghi, Mohammad; Nasr, Marjan; Heller, Stefan

2012-01-01

Hearing loss, caused by irreversible loss of cochlear sensory hair cells, affects millions of patients worldwide. In this concise review, we examine the conundrum of inner ear stem cells, which obviously are present in the inner ear sensory epithelia of nonmammalian vertebrates, giving these ears the ability to functionally recover even from repetitive ototoxic insults. Despite the inability of the mammalian inner ear to regenerate lost hair cells, there is evidence for cells with regenerative capacity because stem cells can be isolated from vestibular sensory epithelia and from the neonatal cochlea. Challenges and recent progress toward identification of the intrinsic and extrinsic signaling pathways that could be used to re-establish stemness in the mammalian organ of Corti are discussed. Copyright © 2011 AlphaMed Press.

Morphological correlation between caloric tests and vestibular hydrops in Ménière's disease using intravenous Gd enhanced inner ear MRI.

PubMed

Choi, Ji Eun; Kim, Yi-Kyung; Cho, Young Sang; Lee, Kieun; Park, Hyun Woo; Yoon, Sung Hoon; Kim, Hyung-Jin; Chung, Won-Ho

2017-01-01

The purpose of this study was to prove the hypothesis that caloric response in Ménière's disease (MD) is reduced by hydropic expansion of the vestibular labyrinth, not by vestibular hypofunction, by evaluating the correlation morphologically using an intravenous Gadolinium (IV-Gd) inner ear MRI. In study I, the prevalence of abnormal video Head Impulse Test (vHIT) results among the patients with definite unilateral MD (n = 24) and vestibular neuritis (VN) (n = 22) were investigated. All patients showed abnormal canal paresis (CP) (> 26%) on caloric tests. The prevalence of abnormal vHIT in patients with abnormal CP was significantly lower in MD patients (12.5%) than that in VN patients (81.8%) (p < 0.001). In study II, morphological correlation between caloric tests and vestibular hydrops level was evaluated in unilateral MD patients (n = 16) who had normal vHIT results. Eleven patients (61%) had abnormal CP. After taking the images of IV-Gd inner ear MRI, the vestibular hydrops ratio (endolymph volume/total lymph volume = %VH) was measured. In addition, the relative vestibular hydrops ratio (%RVH = (%VHaffected ear-%VHunaffected ear) / (%VHaffected ear + %VHunaffected ear)) was calculated. Each ratio (%VH and %RVH) was compared with average peak slow phase velocity (PSPV) and CP, respectively. In the MD patients, %VH of the affected ear correlated significantly with mean PSPV on the same side (rs = -0.569, p = 0.024), while %RVH correlated significantly with CP (rs = 0.602, p = 0.014). In most MD patients (87.5%) compared to VN patients, vHIT results were normal even though the caloric function was reduced. In addition, the reduced caloric function with normal vHIT was related to the severity of the vestibular hydrops measured by the IV-Gd inner ear MRI. These findings concluded that the abnormal caloric tests with normal vHIT in MD indicated severe endolymphatic hydrops rather than vestibular hypofunction.

The Envoy® Totally Implantable Hearing System, St. Croix Medical

PubMed Central

Kroll, Kai; Grant, Iain L.; Javel, Eric

2002-01-01

The Totally Implantable Envoy® System is currently undergoing clinical trials in both the United States and Europe. The fully implantable hearing device is intended for use in patients with sensorineural hearing loss. The device employs piezoelectric transducers to sense ossicle motion and drive the stapes. Programmable signal processing parameters include amplification, compression, and variable frequency response. The fully implantable attribute allows users to take advantage of normal external ear resonances and head-related transfer functions, while avoiding undesirable earmold effects. The high sensitivity, low power consumption, and high fidelity attributes of piezoelectric transducers minimize acoustic feedback and maximize battery life (Gyo, 1996; Yanagihara, (1987) and 2001). The surgical procedure to install the device has been accurately defined and implantation is reversible. PMID:25425915

Multiple enhancers located in a 1-Mb region upstream of POU3F4 promote expression during inner ear development and may be required for hearing

PubMed Central

Naranjo, Silvia; Voesenek, Krysta; de la Calle-Mustienes, Elisa; Robert-Moreno, Alex; Kokotas, Haris; Grigoriadou, Maria; Economides, John; Van Camp, Guy; Hilgert, Nele; Moreno, Felipe; Alsina, Berta; Petersen, Michael B.; Kremer, Hannie

2010-01-01

POU3F4 encodes a POU-domain transcription factor required for inner ear development. Defects in POU3F4 function are associated with X-linked deafness type 3 (DFN3). Multiple deletions affecting up to ~900-kb upstream of POU3F4 are found in DFN3 patients, suggesting the presence of essential POU3F4 enhancers in this region. Recently, an inner ear enhancer was reported that is absent in most DFN3 patients with upstream deletions. However, two indications suggest that additional enhancers in the POU3F4 upstream region are required for POU3F4 function during inner ear development. First, there is at least one DFN3 deletion that does not eliminate the reported enhancer. Second, the expression pattern driven by this enhancer does not fully recapitulate Pou3f4 expression in the inner ear. Here, we screened a 1-Mb region upstream of the POU3F4 gene for additional cis-regulatory elements and searched for novel DFN3 mutations in the identified POU3F4 enhancers. We found several novel enhancers for otic vesicle expression. Some of these also drive expression in kidney, pancreas and brain, tissues that are known to express Pou3f4. In addition, we report a new and smallest deletion identified so far in a DFN3 family which eliminates 3.9 kb, comprising almost exclusively the previous reported inner ear enhancer. We suggest that multiple enhancers control the expression of Pou3f4 in the inner ear and these may contribute to the phenotype observed in DFN3 patients. In addition, the novel deletion demonstrates that the previous reported enhancer, although not sufficient, is essential for POU3F4 function during inner ear development. Electronic supplementary material The online version of this article (doi:10.1007/s00439-010-0864-x) contains supplementary material, which is available to authorized users. PMID:20668882

Proteomic Analysis Revealed Nitrogen-mediated Metabolic, Developmental, and Hormonal Regulation of Maize (Zea mays L.) Ear Growth

PubMed Central

Li, Chunjian; Li, Xuexian

2012-01-01

Optimal nitrogen (N) supply is critical for achieving high grain yield of maize. It is well established that N deficiency significantly reduces grain yield and N oversupply reduces N use efficiency without significant yield increase. However, the underlying proteomic mechanism remains poorly understood. The present field study showed that N deficiency significantly reduced ear size and dry matter accumulation in the cob and grain, directly resulting in a significant decrease in grain yield. The N content, biomass accumulation, and proteomic variations were further analysed in young ears at the silking stage under different N regimes. N deficiency significantly reduced N content and biomass accumulation in young ears of maize plants. Proteomic analysis identified 47 proteins with significant differential accumulation in young ears under different N treatments. Eighteen proteins also responded to other abiotic and biotic stresses, suggesting that N nutritional imbalance triggered a general stress response. Importantly, 24 proteins are involved in regulation of hormonal metabolism and functions, ear development, and C/N metabolism in young ears, indicating profound impacts of N nutrition on ear growth and grain yield at the proteomic level. PMID:22936831

Replication of type 5 adenovirus promotes middle ear infection by Streptococcus pneumoniae in the chinchilla model of otitis media

PubMed Central

Murrah, Kyle A.; Turner, Roberta L.; Pang, Bing; Perez, Antonia C.; Reimche, Jennifer L.; King, Lauren B.; Wren, John; Gandhi, Uma; Swords, W. Edward; Ornelles, David A.

2015-01-01

Adenoviral infection is a major risk factor for otitis media. We hypothesized that adenovirus promotes bacterial ascension into the middle ear through the disruption of normal function in the Eustachian tubes due to inflammation-induced changes. An intranasal infection model of the chinchilla was used to test the ability of type 5 adenovirus to promote middle ear infection by Streptococcus pneumoniae. The hyperinflammatory adenovirus mutant dl327 and the nonreplicating adenovirus mutant H5wt300ΔpTP were used to test the role of inflammation and viral replication, respectively, in promotion of pneumococcal middle ear infection. Precedent infection with adenovirus resulted in a significantly greater incidence of middle ear disease by S. pneumoniae as compared to nonadenovirus infected animals. Infection with the adenovirus mutant dl327 induced a comparable degree of bacterial ascension into the middle ear as did infection with the wild-type virus. By contrast, infection with the nonreplicating adenovirus mutant H5wt300ΔpTP resulted in less extensive middle ear infection compared to the wild-type adenovirus. We conclude that viral replication is necessary for adenoviral-induced pneumococcal middle ear disease. PMID:25251686

Functional evaluation of a cell replacement therapy in the inner ear

PubMed Central

Hu, Zhengqing; Ulfendahl, Mats; Prieskorn, Diane M.; Olivius, N. Petri; Miller, Josef M.

2015-01-01

Hypothesis Cell replacement therapy in the inner ear will contribute to the functional recovery of hearing loss. Background Cell replacement therapy is a potentially powerful approach to replace degenerated or severely damaged spiral ganglion neurons. This study aimed at stimulating the neurite outgrowth of the implanted neurons and enhancing the potential therapeutic of inner ear cell implants. Methods Chronic electrical stimulation (CES) and exogenous neurotrophic growth factor (NGF) were applied to 46 guinea pigs transplanted with embryonic dorsal root ganglion (DRG) neurons four days post deafening. The animals were evaluated with the electrically-evoked auditory brain stem responses (EABRs) at experimental day 7, 11, 17, 24, 31. The animals were euthanized at day 31 and the inner ears were dissected out for immunohistochemistry investigation. Results Implanted DRG cells, identified by EGFP fluorescence and a neuronal marker, were found close to Rosenthal's canal in the adult inner ear for up to four weeks following transplantation. Extensive neurite projections clearly, greater than in non-treated animals, were observed to penetrate the bony modiolus and reach the spiral ganglion region in animals supplied with CES and/or NGF. There was, however, no significant difference in the thresholds of EABRs between DRG-transplanted-animals supplied with CES and/or NGF and DRG-transplanted animals without CES or NGF supplement. Conclusions The results suggest that CES and/or NGF can stimulate neurite outgrowth from implanted neurons, although based on EABR measurement these interventions did not induce functional connections to the central auditory pathway. Additional time or novel approaches may enhance functional responsiveness of implanted cells in the adult cochlea. PMID:19395986

Should children who use cochlear implants wear hearing aids in the opposite ear?

PubMed

Ching, T Y; Psarros, C; Hill, M; Dillon, H; Incerti, P

2001-10-01

The aim of this study was to investigate 1) whether a hearing aid needs to be adjusted differently depending on whether a child wears a cochlear implant or another hearing aid in the contralateral ear; 2) whether the use of a hearing aid and a cochlear implant in opposite ears leads to binaural interference; and 3) whether the use of a hearing aid and a cochlear implant in opposite ears leads to binaural benefits in speech perception, localization, and communicative functioning in real life. Sixteen children participated in this study. All children used a Nucleus 22 or Nucleus 24 cochlear implant system programmed with the SPEAK strategy in one ear. The hearing aid amplification requirements in the nonimplanted ear of these children were determined using two procedures. A paired comparison technique was used to identify the frequency response that was best for speech intelligibility in quiet, and a loudness balancing technique was used to match the loudness of speech in the ear with a hearing aid to that with a cochlear implant. Eleven of the 16 children participated in the investigation of binaural effects. Performance in speech perception, localization, and communicative functioning was assessed under four aided conditions: cochlear implant with hearing aid as worn, cochlear implant alone, hearing aid alone, and cochlear implant with hearing aid adjusted according to individual requirements. Fifteen of the 16 children whose amplification requirements were determined preferred a hearing aid frequency response that was within +/-6 dB/octave of the NAL-RP prescription. On average, the children required 6 dB more gain than prescribed to balance the loudness of the implanted ear for a speech signal presented at 65 dB SPL. For all 11 children whose performance was evaluated for investigating binaural effects, there was no indication of significantly poorer performance under bilaterally aided conditions compared with unilaterally aided conditions. On average, there were significant benefits in speech perception, localization, and aural/oral function when the children used cochlear implants with adjusted hearing aids than when they used cochlear implants alone. All individuals showed benefits in at least one of the measures. Hearing aids for children who also use cochlear implants can be selected using the NAL-RP prescription. Adjustment of hearing aid gain to match loudness in the implanted ear can facilitate integration of signals from both ears, leading to better speech perception. Given that there are binaural advantages from using cochlear implants with hearing aids in opposite ears, clinicians should advise parents and other professionals about these potential advantages, and facilitate bilateral amplification by adjusting hearing aids after stable cochlear implant MAPs are established.

Age and Gender Effects on Wideband Absorbance in Adults with Normal Outer and Middle Ear Function

ERIC Educational Resources Information Center

Mazlan, Rafidah; Kei, Joseph; Ya, Cheng Li; Yusof, Wan Nur Hanim Mohd; Saim, Lokman; Zhao, Fei

2015-01-01

Purpose: This study examined the effects of age and gender on wideband energy absorbance in adults with normal middle ear function. Method: Forty young adults (14 men, 26 women, aged 20-38 years), 31 middle-aged adults (16 men, 15 women, aged 42-64 years), and 30 older adults (20 men, 10 women, aged 65-82 years) were assessed. Energy absorbance…

Intra- and interspecific responses to Rafinesque’s big-eared bat (Corynorhinus rafinesquii) social calls

Treesearch

S. Loeb; E. Britzke

2010-01-01

Bats respond to the calls of conspecifics as well as to calls of other species; however, few studies have attempted to quantify these responses or understand the functions of these calls. We tested the response of Rafinesque’s big-eared bats (Corynorhinus rafinesquii) to social calls as a possible method to increase capture success and to understand the function of...

Distortion product otoacoustic emission suppression tuning and acoustic admittance in human infants: Birth through 6 months

PubMed Central

Abdala, Carolina; Keefe, Douglas H.; Oba, Sandra I.

2009-01-01

Previous work has reported non-adultlike distortion product otoacoustic emission (DPOAE) suppression in human newborns at f2 =6000 Hz, indicating an immaturity in peripheral auditory function. In this study, DPOAE suppression tuning curves (STCs) were recorded as a measure of cochlear function and acoustic admittance/reflectance (YR) in the ear canal recorded as a measure of middle-ear function, in the same 20 infants at birth and through 6 months of age. DPOAE STCs changed little from birth through 6 months, showing excessively narrow and sharp tuning throughout the test period. In contrast, several middle-ear indices at corresponding frequencies shifted systematically with increasing age, although they also remained non-adultlike at 6 months. Linear correlations were conducted between YR and DPOAE suppression features. Only two correlations out of 76 were significant, and all but three YR variables accounted for <10% of the variance in DPOAE suppression tuning. The strongest correlation was noted between admittance phase at 5700 Hz and STC tip-to-tail (R=0.49). The association between middle-ear variables and DPOAE suppression may be stronger during other developmental time periods. Study of older infants and children is needed to fully define postnatal immaturity of human peripheral auditory function. PMID:17552713

Immunolocalization of aquaporin CHIP in the guinea pig inner ear.

PubMed

Stanković, K M; Adams, J C; Brown, D

1995-12-01

Aquaporin CHIP (AQP-CHIP) is a water channel protein previously identified in red blood cells and water transporting epithelia. The inner ear is an organ of hearing and balance whose normal function depends critically on maintenance of fluid homeostasis. In this study, AQP-CHIP, or a close homologue, was found in specific cells of the inner ear, as assessed by immunocytochemistry with the use of affinity-purified polyclonal antibodies against AQP-CHIP.AQP-CHIP was predominantly found in fibrocytes in close association with bone, including most of the cells lining the bony labyrinth and in fibrocytes lining the endolymphatic duct and sac. AQP-CHIP-positive cells not directly apposing bone include cells under the basilar membrane, some type III fibrocytes of the spiral ligament, fibrocytes of the spiral limbus, and the trabecular perilymphatic tissue extending from the membranous to the bony labyrinth. AQP-CHIP was also found in the periosteum of the middle ear and cranial bones, as well as in chondrocytes of the oval window and stapes. The distribution of AQP-CHIP in the inner ear suggests that AQP-CHIP may have special significance for maintenance of bone and the basilar membrane, and for function of the spiral ligament.

Asymmetric Hearing During Development: The Aural Preference Syndrome and Treatment Options.

PubMed

Gordon, Karen; Henkin, Yael; Kral, Andrej

2015-07-01

Deafness affects ∼2 in 1000 children and is one of the most common congenital impairments. Permanent hearing loss can be treated by fitting hearing aids. More severe to profound deafness is an indication for cochlear implantation. Although newborn hearing screening programs have increased the identification of asymmetric hearing loss, parents and caregivers of children with single-sided deafness are often hesitant to pursue therapy for the deaf ear. Delayed intervention has consequences for recovery of hearing. It has long been reported that asymmetric hearing loss/single-sided deafness compromises speech and language development and educational outcomes in children. Recent studies in animal models of deafness and in children consistently show evidence of an "aural preference syndrome" in which single-sided deafness in early childhood reorganizes the developing auditory pathways toward the hearing ear, with weaker central representation of the deaf ear. Delayed therapy consequently compromises benefit for the deaf ear, with slow rates of improvement measured over time. Therefore, asymmetric hearing needs early identification and intervention. Providing early effective stimulation in both ears through appropriate fitting of auditory prostheses, including hearing aids and cochlear implants, within a sensitive period in development has a cardinal role for securing the function of the impaired ear and for restoring binaural/spatial hearing. The impacts of asymmetric hearing loss on the developing auditory system and on spoken language development have often been underestimated. Thus, the traditional minimalist approach to clinical management aimed at 1 functional ear should be modified on the basis of current evidence. Copyright © 2015 by the American Academy of Pediatrics.

Healthy-side dominance of middle- and long-latency neuromagnetic fields in idiopathic sudden sensorineural hearing loss.

PubMed

Li, L P H; Shiao, A S; Chen, L F; Niddam, D M; Chang, S Y; Lien, C F; Lee, S K; Hsieh, J C

2006-08-01

Any lesion along the neural axis may induce a subsequent functional reorganization at the level above. The present study used magnetoencephalography to investigate auditory-evoked magnetic fields [a component of the middle-latency auditory evoked fields peaking at approximately 50 ms (P50m) and a component of the long-latency auditory evoked fields peaking at approximately 100 ms (N100m)] on stimulation of both healthy and affected ears in patients with acute unilateral idiopathic sudden sensorineural hearing loss (ISSNHL) of moderate degree in order to elucidate the functional plasticity of the auditory system. Sixteen right-handed, previously untreated adult patients with acute unilateral left (n = 8) or right (n = 8) ISSNHL of moderate degree were studied. Sixteen right-handed healthy volunteers with normal hearing served as control. Auditory neuromagnetic responses, measured by a whole-head 306-channel neuromagnetometer, were detected by monaural tone stimulation applied to affected and healthy ears, respectively, in different sessions. Intragroup and intergroup interhemispheric differences of peak dipole strengths and latencies of P50m and N100m, respectively, to monaural tones were evaluated. Healthy-side amplitude dominance of both P50m and N100m was found in ISSNHL, i.e. contralateral dominance was preserved on affected-ear stimulation but ipsilateral dominance was seen on healthy-ear stimulation. The phenomena could be attributed to the combined contralateral attenuation and ipsilateral enhancement of P50m and N100m activity in response to healthy-ear stimulation. Our findings confirmed that functional modulation can occur within the first few tens of milliseconds of evoked response at the auditory cortex in ISSNHL. The mechanisms of healthy-side dominance might be ascribed to a functional retune of auditory pathways, i.e. conjoined contralateral inhibition and ipsilateral excitation of the auditory pathway in response to healthy-ear stimulation. The effect could be registered in cortical responses.

Flexibility in the mouse middle ear: A finite element study of the frequency response

NASA Astrophysics Data System (ADS)

Gottlieb, Peter; Puria, Sunil

2018-05-01

The mammalian middle ear is comprised of three distinct ossicles, connected by joints, and suspended in an air-filled cavity. In most mammals, the ossicular joints are mobile synovial joints, which introduce flexibility into the ossicular chain. In some smaller rodents, however, these joints are less mobile, and in the mouse in particular, the malleus is additionally characterized by a large, thin plate known as the transversal lamina, which connects the manubrium to the incus-malleus joint (IMJ). We hypothesize that this feature acts as a functional joint, maintaining the benefits of a flexible ossicular chain despite a less-mobile IMJ, and tested this hypothesis with a finite element model of the mouse middle ear. The results showed that while fusing the ossicular joints had a negligible effect on sound transmission, stiffening the ossicular bone significantly reduced sound transmission, implying that bone flexibility plays a critical role in the normal function of the mouse middle ear.

Emergence of unreported stimuli into imagery as a function of laterality of presentation: a replication and extension of research by Henley & Dixon (1974).

PubMed

Mykel, N; Daves, W F

1979-05-01

In Expt. 1, the research by Henley & Dixon (1974) was replicated. Two experimental groups (n=8 each) received subliminal words to the right ear and 8 min of music to the left ear or vice versa. Each group had its own control (n=8 each) with only music to one ear. Categorization and ranking of imagery reported, as well as performance on a checklist containing critical, associated, and non-related words, showed that emergence was greater with words to the right ear than with no words. There was no difference between experimental and control groups with words to the left ear. In Expt. 2, the music was eliminated, and subjects received subliminal words to the right ear (n=8) or no words. A significant difference between groups was found when the reported imagery was ranked as to emergence, and on the checklist, but not when the reports were categorized by judges.

15 CFR 746.3 - Iraq.

Code of Federal Regulations, 2014 CFR

2014-01-01

...) or ECCNs that end in the number “018” or items classified under “600 series” ECCNs, that would make a material contribution to the production, research, design, development, support, maintenance or manufacture... any item subject to the EAR if, at the time of the export, reexport or transfer, you know, have reason...

15 CFR 762.2 - Records to be retained.

Code of Federal Regulations, 2013 CFR

2013-01-01

... minimis calculation (method). (c) Special recordkeeping requirement—(1) Libya. Persons in receipt of a... the export to Libya of any item subject to the EAR must maintain a record of those items transferred to Libya pursuant to such specific license and record when the items are consumed or destroyed in the...

15 CFR 762.2 - Records to be retained.

Code of Federal Regulations, 2012 CFR

2012-01-01

... minimis calculation (method). (c) Special recordkeeping requirement—(1) Libya. Persons in receipt of a... the export to Libya of any item subject to the EAR must maintain a record of those items transferred to Libya pursuant to such specific license and record when the items are consumed or destroyed in the...

Confirming QTL for aflatoxin resistance from Mp313E in different genetic backgrounds

USDA-ARS?s Scientific Manuscript database

The fungus Aspergillus flavus (Link:Fr) causes ear rot of maize (Zea mays L.) and produces the toxic metabolic product aflatoxin. One particularly effective method to control the fungus is via host plant resistance, but while several resistant breeding lines have been identified, transferring the r...

A method for determining weights for excess relative risk and excess absolute risk when applied in the calculation of lifetime risk of cancer from radiation exposure.

PubMed

Walsh, Linda; Schneider, Uwe

2013-03-01

Radiation-related risks of cancer can be transported from one population to another population at risk, for the purpose of calculating lifetime risks from radiation exposure. Transfer via excess relative risks (ERR) or excess absolute risks (EAR) or a mixture of both (i.e., from the life span study (LSS) of Japanese atomic bomb survivors) has been done in the past based on qualitative weighting. Consequently, the values of the weights applied and the method of application of the weights (i.e., as additive or geometric weighted means) have varied both between reports produced at different times by the same regulatory body and also between reports produced at similar times by different regulatory bodies. Since the gender and age patterns are often markedly different between EAR and ERR models, it is useful to have an evidence-based method for determining the relative goodness of fit of such models to the data. This paper identifies a method, using Akaike model weights, which could aid expert judgment and be applied to help to achieve consistency of approach and quantitative evidence-based results in future health risk assessments. The results of applying this method to recent LSS cancer incidence models are that the relative EAR weighting by cancer solid cancer site, on a scale of 0-1, is zero for breast and colon, 0.02 for all solid, 0.03 for lung, 0.08 for liver, 0.15 for thyroid, 0.18 for bladder and 0.93 for stomach. The EAR weighting for female breast cancer increases from 0 to 0.3, if a generally observed change in the trend between female age-specific breast cancer incidence rates and attained age, associated with menopause, is accounted for in the EAR model. Application of this method to preferred models from a study of multi-model inference from many models fitted to the LSS leukemia mortality data, results in an EAR weighting of 0. From these results it can be seen that lifetime risk transfer is most highly weighted by EAR only for stomach cancer. However, the generalization and interpretation of radiation effect estimates based on the LSS cancer data, when projected to other populations, are particularly uncertain if considerable differences exist between site-specific baseline rates in the LSS and the other populations of interest. Definitive conclusions, regarding the appropriate method for transporting cancer risks, are limited by a lack of knowledge in several areas including unknown factors and uncertainties in biological mechanisms and genetic and environmental risk factors for carcinogenesis; uncertainties in radiation dosimetry; and insufficient statistical power and/or incomplete follow-up in data from radio-epidemiological studies.

Patients' satisfaction after ear reconstruction with autologous rib cartilage.

PubMed

Kristiansen, Martina; Öberg, Martin; Wikström, Sven Olof

2013-04-01

Patients' satisfaction is an important outcome measure in reconstructive surgery and quality assurance is today central in the clinical practice. The aim of this study was to evaluate the patients' satisfaction with the process and final result after reconstruction for congenital microtia. A questionnaire was designed and sent to 78 patients who had undergone unilateral ear reconstruction with autologous rib cartilage during the period 2000-2010. For a multidimensional view the patients answered 42 questions about aesthetic, functional, psychosocial, and clinic-related outcomes. The response rate was 76% (59/78 patients). The patients were generally satisfied with the aesthetic result of the ear and had function gain in being able to wear glasses; however, some patients did report new different functional problems after the operation. Still, almost all patients felt that the ear was a part of them and would have chosen the same operative procedure if they could do it again. The patients were overall highly satisfied with the care process. This surgery-specific questionnaire is an important tool for quality assurance in this clinical practice. These findings can help to improve the preoperative information to meet the patients' notions, expectations, and fears.

[The experimental research of inner ear metabolism and electrical physiology of autoimmune sensorineural hearing loss].

PubMed

Tan, C; Cao, Y; Hu, P

1998-09-01

Inquire into the mechanism of inner ear pathological physiology in autoimmune sensorineural hearing loss (ASHL). With the auditory electric-physiological techniques and enzyme-histochemical method, the change of inner ear hearing function and enzyme activity were observed. These animals, which threshold of auditory nerve compound active potential (CAP) and cochlear microphonic potential(CM) heightening evidently, showed that the amplitude of endolymphatic potential(EP) (include-EP) bring down in various degrees, which was related to the change of the active of Na(+)-K(+)-ATPase and SDH in vascularis stria and endolymphatic sac. The abnormality of enzymes metabolism in inner ear tissues, which following autoimmune inflammation damage, is the pathological foundation of hearing dysfunction.

The genetics of hair-cell function in zebrafish.

PubMed

Nicolson, Teresa

2017-09-01

Our ears are remarkable sensory organs, providing the important senses of balance and hearing. The complex structure of the inner ear, or 'labyrinth', along with the assorted neuroepithelia, have evolved to detect head movements and sounds with impressive sensitivity. The rub is that the inner ear is highly vulnerable to genetic lesions and environmental insults. According to National Institute of Health estimates, hearing loss is one of the most commonly inherited or acquired sensorineural diseases. To understand the causes of deafness and balance disorders, it is imperative to understand the underlying biology of the inner ear, especially the inner workings of the sensory receptors. These receptors, which are termed hair cells, are particularly susceptible to genetic mutations - more than two dozen genes are associated with defects in this cell type in humans. Over the past decade, a substantial amount of progress has been made in working out the molecular basis of hair-cell function using vertebrate animal models. Given the transparency of the inner ear and the genetic tools that are available, zebrafish have become an increasingly popular animal model for the study of deafness and vestibular dysfunction. Mutagenesis screens for larval defects in hearing and balance have been fruitful in finding key components, many of which have been implicated in human deafness. This review will focus on the genes that are required for hair-cell function in zebrafish, with a particular emphasis on mechanotransduction. In addition, the generation of new tools available for the characterization of zebrafish hair-cell mutants will be discussed.

Magnetic Beads Enhance Adhesion of NIH 3T3 Fibroblasts: A Proof-of-Principle In Vitro Study for Implant-Mediated Long-Term Drug Delivery to the Inner Ear

PubMed Central

Aliuos, Pooyan; Schulze, Jennifer; Schomaker, Markus; Reuter, Günter; Stolle, Stefan R. O.; Werner, Darja; Ripken, Tammo; Lenarz, Thomas; Warnecke, Athanasia

2016-01-01

Introduction Long-term drug delivery to the inner ear may be achieved by functionalizing cochlear implant (CI) electrodes with cells providing neuroprotective factors. However, effective strategies in order to coat implant surfaces with cells need to be developed. Our vision is to make benefit of electromagnetic field attracting forces generated by CI electrodes to bind BDNF-secreting cells that are labelled with magnetic beads (MB) onto the electrode surfaces. Thus, the effect of MB-labelling on cell viability and BDNF production were investigated. Materials and Methods Murine NIH 3T3 fibroblasts—genetically modified to produce BDNF—were labelled with MB. Results Atomic force and bright field microscopy illustrated the internalization of MB by fibroblasts after 24 h of cultivation. Labelling cells with MB did not expose cytotoxic effects on fibroblasts and allowed adhesion on magnetic surfaces with sufficient BDNF release. Discussion Our data demonstrate a novel approach for mediating enhanced long-term adhesion of BDNF-secreting fibroblasts on model electrode surfaces for cell-based drug delivery applications in vitro and in vivo. This therapeutic strategy, once transferred to cells suitable for clinical application, may allow the biological modifications of CI surfaces with cells releasing neurotrophic or other factors of interest. PMID:26918945

Characteristics of laser-induced shock wave injury to the inner ear of rats

NASA Astrophysics Data System (ADS)

Kurioka, Takaomi; Matsunobu, Takeshi; Niwa, Katsuki; Tamura, Atsushi; Kawauchi, Satoko; Satoh, Yasushi; Sato, Shunichi; Shiotani, Akihiro

2014-12-01

Recently, the number of blast injuries of the inner ear has increased in the general population. In blast-induced inner ear injury, a shock wave (SW) component in the blast wave is considered to play an important role in sensorineural hearing loss. However, the mechanisms by which an SW affects inner ear tissue remain largely unknown. We aimed to establish a new animal model for SW-induced inner ear injury by using laser-induced SWs (LISWs) on rats. The LISWs were generated by irradiating an elastic laser target with 694-nm nanosecond pulses of a ruby laser. After LISW application to the cochlea through bone conduction, auditory measurements revealed the presence of inner ear dysfunction, the extent of which depended on LISW overpressure. A significantly lower survival rate of hair cells and spiral ganglion neurons, as well as severe oxidative damage, were observed in the inner ear exposed to an LISW. Although considerable differences in the pressure characteristics exist between LISWs and SWs in real blast waves, the functional and morphological changes shown by the present LISW-based model were similar to those observed in real blast-induced injury. Thus, our animal model is expected to be useful for laboratory-based research of blast-induced inner ear injury.

Numerical evaluation of implantable hearing devices using a finite element model of human ear considering viscoelastic properties.

PubMed

Zhang, Jing; Tian, Jiabin; Ta, Na; Huang, Xinsheng; Rao, Zhushi

2016-08-01

Finite element method was employed in this study to analyze the change in performance of implantable hearing devices due to the consideration of soft tissues' viscoelasticity. An integrated finite element model of human ear including the external ear, middle ear and inner ear was first developed via reverse engineering and analyzed by acoustic-structure-fluid coupling. Viscoelastic properties of soft tissues in the middle ear were taken into consideration in this model. The model-derived dynamic responses including middle ear and cochlea functions showed a better agreement with experimental data at high frequencies above 3000 Hz than the Rayleigh-type damping. On this basis, a coupled finite element model consisting of the human ear and a piezoelectric actuator attached to the long process of incus was further constructed. Based on the electromechanical coupling analysis, equivalent sound pressure and power consumption of the actuator corresponding to viscoelasticity and Rayleigh damping were calculated using this model. The analytical results showed that the implant performance of the actuator evaluated using a finite element model considering viscoelastic properties gives a lower output above about 3 kHz than does Rayleigh damping model. Finite element model considering viscoelastic properties was more accurate to numerically evaluate implantable hearing devices. © IMechE 2016.

Comparison between the angle of Eustachian tube in patients with chronic suppurative otitis media and normal ears based on computed tomography scan of temporal bones in Haji Adam Malik general hospital Medan

NASA Astrophysics Data System (ADS)

Masita, S.; Zahara, D.; Aboet, A.

2018-03-01

The function of the Eustachian tube plays a significant role in increased risk chronic suppurative otitis media (CSOM). The angle of the Eustachian tube is a predisposing factor for Eustachian tube dysfunction and clearance disorder of the middle ear. The aim of this study was to compare the mean angle of a Eustachian tube of CSOM ears and normal ears. This research was a cross-sectional study consisting of 19 patients of CSOM without cholesteatoma, 19 patients of CSOM with cholesteatoma and 19 patients with normal ears. All patients were examined using CT Temporal, and the angle of the eustachian tube was measured using multiplanar reconstruction technique. The mean angle of Eustachian tube in CSOM patients without cholesteatoma was 32.82° (SD=3.82), in CSOM with cholesteatoma was 27.74° (SD=4.44) and in normal ears was 33.61° (SD=3.83). Based on Kruskal-Wallis test, there was a significant difference in the angle of a Eustachian tube of these three groups (p<0.001). There was a significant difference between the mean angle of the Eustachian tube in CSOM ears and normal ears.

Characteristics of laser-induced shock wave injury to the inner ear of rats.

PubMed

Kurioka, Takaomi; Matsunobu, Takeshi; Niwa, Katsuki; Tamura, Atsushi; Kawauchi, Satoko; Satoh, Yasushi; Sato, Shunichi; Shiotani, Akihiro

2014-12-01

Recently, the number of blast injuries of the inner ear has increased in the general population. In blast-induced inner ear injury, a shock wave (SW) component in the blast wave is considered to play an important role in sensorineural hearing loss. However, the mechanisms by which an SW affects inner ear tissue remain largely unknown. We aimed to establish a new animal model for SW-induced inner ear injury by using laser-induced SWs (LISWs) on rats. The LISWs were generated by irradiating an elastic laser target with 694-nm nanosecond pulses of a ruby laser. After LISW application to the cochlea through bone conduction, auditory measurements revealed the presence of inner ear dysfunction, the extent of which depended on LISW overpressure. A significantly lower survival rate of hair cells and spiral ganglion neurons, as well as severe oxidative damage, were observed in the inner ear exposed to an LISW. Although considerable differences in the pressure characteristics exist between LISWs and SWs in real blast waves, the functional and morphological changes shown by the present LISW-based model were similar to those observed in real blast-induced injury. Thus, our animal model is expected to be useful for laboratory-based research of blast-induced inner ear injury.

Decompression sickness in breath-hold diving, and its probable connection to the growth and dissolution of small arterial gas emboli.

PubMed

Goldman, Saul; Solano-Altamirano, J M

2015-04-01

We solved the Laplace equation for the radius of an arterial gas embolism (AGE), during and after breath-hold diving. We used a simple three-region diffusion model for the AGE, and applied our results to two types of breath-hold dives: single, very deep competitive-level dives and repetitive shallower breath-hold dives similar to those carried out by indigenous commercial pearl divers in the South Pacific. Because of the effect of surface tension, AGEs tend to dissolve in arterial blood when arteries remote from supersaturated tissue. However if, before fully dissolving, they reach the capillary beds that perfuse the brain and the inner ear, they may become inflated with inert gas that is transferred into them from these contiguous temporarily supersaturated tissues. By using simple kinetic models of cerebral and inner ear tissue, the nitrogen tissue partial pressures during and after the dive(s) were determined. These were used to theoretically calculate AGE growth and dissolution curves for AGEs lodged in capillaries of the brain and inner ear. From these curves it was found that both cerebral and inner ear decompression sickness are expected to occur occasionally in single competitive-level dives. It was also determined from these curves that for the commercial repetitive dives considered, the duration of the surface interval (the time interval separating individual repetitive dives from one another) was a key determinant, as to whether inner ear and/or cerebral decompression sickness arose. Our predictions both for single competitive-level and repetitive commercial breath-hold diving were consistent with what is known about the incidence of cerebral and inner ear decompression sickness in these forms of diving. Copyright © 2015 Elsevier Inc. All rights reserved.

Effect of hearing aids on auditory function in infants with perinatal brain injury and severe hearing loss.

PubMed

Moreno-Aguirre, Alma Janeth; Santiago-Rodríguez, Efraín; Harmony, Thalía; Fernández-Bouzas, Antonio

2012-01-01

Approximately 2-4% of newborns with perinatal risk factors present with hearing loss. Our aim was to analyze the effect of hearing aid use on auditory function evaluated based on otoacoustic emissions (OAEs), auditory brain responses (ABRs) and auditory steady state responses (ASSRs) in infants with perinatal brain injury and profound hearing loss. A prospective, longitudinal study of auditory function in infants with profound hearing loss. Right side hearing before and after hearing aid use was compared with left side hearing (not stimulated and used as control). All infants were subjected to OAE, ABR and ASSR evaluations before and after hearing aid use. The average ABR threshold decreased from 90.0 to 80.0 dB (p = 0.003) after six months of hearing aid use. In the left ear, which was used as a control, the ABR threshold decreased from 94.6 to 87.6 dB, which was not significant (p>0.05). In addition, the ASSR threshold in the 4000-Hz frequency decreased from 89 dB to 72 dB (p = 0.013) after six months of right ear hearing aid use; the other frequencies in the right ear and all frequencies in the left ear did not show significant differences in any of the measured parameters (p>0.05). OAEs were absent in the baseline test and showed no changes after hearing aid use in the right ear (p>0.05). This study provides evidence that early hearing aid use decreases the hearing threshold in ABR and ASSR assessments with no functional modifications in the auditory receptor, as evaluated by OAEs.

Effect of Hearing Aids on Auditory Function in Infants with Perinatal Brain Injury and Severe Hearing Loss

PubMed Central

Moreno-Aguirre, Alma Janeth; Santiago-Rodríguez, Efraín; Harmony, Thalía; Fernández-Bouzas, Antonio

2012-01-01

Background Approximately 2–4% of newborns with perinatal risk factors present with hearing loss. Our aim was to analyze the effect of hearing aid use on auditory function evaluated based on otoacoustic emissions (OAEs), auditory brain responses (ABRs) and auditory steady state responses (ASSRs) in infants with perinatal brain injury and profound hearing loss. Methodology/Principal Findings A prospective, longitudinal study of auditory function in infants with profound hearing loss. Right side hearing before and after hearing aid use was compared with left side hearing (not stimulated and used as control). All infants were subjected to OAE, ABR and ASSR evaluations before and after hearing aid use. The average ABR threshold decreased from 90.0 to 80.0 dB (p = 0.003) after six months of hearing aid use. In the left ear, which was used as a control, the ABR threshold decreased from 94.6 to 87.6 dB, which was not significant (p>0.05). In addition, the ASSR threshold in the 4000-Hz frequency decreased from 89 dB to 72 dB (p = 0.013) after six months of right ear hearing aid use; the other frequencies in the right ear and all frequencies in the left ear did not show significant differences in any of the measured parameters (p>0.05). OAEs were absent in the baseline test and showed no changes after hearing aid use in the right ear (p>0.05). Conclusions/Significance This study provides evidence that early hearing aid use decreases the hearing threshold in ABR and ASSR assessments with no functional modifications in the auditory receptor, as evaluated by OAEs. PMID:22808289

The evolutionary origin of auditory receptors in Tettigonioidea: the complex tibial organ of Schizodactylidae

NASA Astrophysics Data System (ADS)

Strauß, Johannes; Lakes-Harlan, Reinhard

2009-01-01

Audition in insects is of polyphyletic origin. Tympanal ears derived from proprioceptive or vibratory receptor organs, but many questions of the evolution of insect auditory systems are still open. Despite the rather typical bauplan of the insect body, e.g., with a fixed number of segments, tympanal ears evolved at very different places, but only ensiferans have ears at the foreleg tibia, located in the tibial organ. The homology and monophyly of ensiferan ears is controversial, and no precursor organ was unambiguously identified for auditory receptors. The latter can only be identified by comparative study of recent atympanate taxa. These atympanate taxa are poorly investigated. In this paper, we report the neuroanatomy of the tibial organ of Comicus calcaris (Irish 1986), an atympanate Schizodactylid (splay-footed cricket). This representative of a Gondwana relict group has a tripartite sensory organ, homologous to tettigoniid ears. A comparison with morphology-based cladistic phylogeny indicates that the tripartite neuronal organization present in the majority of Tettigonioidea presumably preceded evolution of a hearing sense in the Tettigonioidea. Furthermore, the absence of a tripartite organ in Grylloidea argues against a monophyletic origin and homology of the cricket and katydid ears. The tracheal attachment of sensory neurons typical for ears of Tettigonioidea is present in C. calcaris and may have facilitated cooption for auditory function. The functional auditory organ was presumably formed in evolution by successive non-neural modifications of trachea and tympana. This first investigation of the neuroanatomy of Schizodactylidae suggests a non-auditory chordotonal organ as the precursor for auditory receptors of related tympanate taxa and adds evidence for the phylogenetic position of the group.

The Impact of Otitis Media with Effusion on Infant Phonetic Perception

ERIC Educational Resources Information Center

Polka, Linda; Rvachew, Susan

2005-01-01

The effect of prior otitis media with effusion (OME) or current middle ear effusion (MEE) on phonetic perception was examined by testing infants' discrimination of "boo" and "goo" syllables in 2 test sessions. Middle ear function was assessed following each perception test using tympanometry. Perceptual performance was compared…

Long-term evaluation of the effect of middle ear effusion on the vestibular system in children.

PubMed

Pazdro-Zastawny, Katarzyna; Pośpiech, Lucyna; Zatoński, Tomasz

2018-06-01

Otitis media with effusion (OME) is one of the most common clinical conditions in childhood. Fluid accumulation in the middle ear may impact inner ear. The purpose of this random sample cohort study was to investigate whether the past history of middle ear effusion has a long-term negative impact on the vestibular system in children. The study was carried out on 22 children aged 7-15 years who had undergone drainage of the middle ear 5 years before evaluation. The control group consisted of 29 healthy children aged 4-17 years. Vestibular function was examined using sway posturography and electronystagmography (ENG). The stabilogram parameters of the study group and the control group were compared. The field of developed area (FDA) and the average body sway velocity (ASV) were analyzed. Elevated stabilogram parameters of FDA and ASV, both with eyes open and eyes closed, were found in the study group. Statistically significant values (p < 0.05) were present for ASV with eyes open and with eyes closed. The ENG recordings were analyzed in both groups. In the study group, spontaneous nystagmus was observed in 40.9% of the children and positional nystagmus occurred in 63.6% of the children. According to tests, eye tracking test was impaired in 27.3% of cases. Rotatory chair testing revealed asymmetry in 18.2% of the children. The presence of effusion in the middle ear in the past has a negative impact on the vestibular part of the inner ear. Clinicians should be aware of the possible negative impact of middle ear effusion on the vestibular function in children with a history of otitis media with effusion. With seeimingly asymptomatic children clinicians should inquire parents about symptoms of dysequlibrium and imbalance. Copyright © 2018 Elsevier B.V. All rights reserved.

Continuous 24-hour measurement of middle ear pressure.

PubMed

Tideholm, B; Jönsson, S; Carlborg, B; Welinder, R; Grenner, J

1996-07-01

A new method was developed for continuous measurement of the middle ear pressure during a 24-h period. The equipment consisted of a piezo-electric pressure device and a digital memory. To allow continuous pressure recordings during normal every-day activities the equipment was made light and portable. The measurement accuracy of the equipment as well as the base-line and temperature stability were tested and found to meet to our requirements satisfactorily. In 4 volunteers with different middle ear conditions, a small perforation was made through the tympanic membrane. A rubber stopper containing a small polyethylene tube was fitted into the external ear canal. Tubal function tests were made to establish the equipment's ability to monitor fast pressure changes. The tests were well in accordance with other methods of direct pressure measurements. The equipment was carried by the volunteers for 24 h to monitor any slow or rapid dynamic pressure changes in the middle ear. Four continuous 24-h measurements are presented. The method was found to be suitable for valid measurements of dynamic pressure changes in the middle ear during normal every-day activities. It may become a useful instrument in the search for a better understanding of the development of chronic middle ear disease.

Influence of different boundary conditions at the tympanic annulus on finite element models of the human middle ear

NASA Astrophysics Data System (ADS)

Lobato, Lucas; Paul, Stephan; Cordioli, Júlio

2018-05-01

The tympanic annulus is a fibrocartilage ligament that supports the tympanic membrane in a sulcus at the end of the outer ear canal. Among many FE models of the middle ear found in literature, the effect of different boundary conditions at tympanic annulus on middle ear mechanics was not found. In order to investigate the influence of different representations of this detail in FE models, three different ways to connect the tympanic annulus to the outer ear canal were modelled in a reduced middle ear system. This reduced system includes tympanic membrane, tympanic annulus, manubrium, malleus and anterior ligament of malleus. The numerical frequency response function Humbo (umbo velocity vs sound pressure at tympanic membrane) was analyzed through the different boundary conditions and compared to numerical and experimental data from the literature. Also a numerical modal analysis was performed to improve the analysis. It was found that the boundary conditions used to represent the connection between Tympanic Annulus and Outer Ear Canal can change the global stiffness of the system and its natural frequencies as well as change the modal shape of high order modes.

Inner ear test battery in guinea pig models - a review.

PubMed

Young, Yi-Ho

2018-06-01

This study reviewed the development of the inner ear test battery comprising auditory brainstem response (ABR), and caloric, ocular vestibular-evoked myogenic potential (oVEMP), and cervical vestibular-evoked myogenic potential (cVEMP) tests in guinea pig models at our laboratory over the last 20 years. Detailed description of the methodology for testing the small animals is also included. Inner ear disorders, i.e. ototoxicity, noise exposure, or perilymph fistula were established in guinea pig models first. One to four weeks after operation, each animal underwent ABR, oVEMP, cVEMP, and caloric tests. Then, animals were sacrificed for morphological study in the temporal bones. Inner ear endorgans can be comprehensively evaluated in guinea pig models via an inner ear test battery, which provides thorough information on the cochlea, saccule, utricle, and semicircular canal function of guinea pigs. Coupled with morphological study in the temporal bones of the animals may help elucidate the mechanism of inner ear disorders in humans. The inner ear test battery in guinea pig models may encourage young researchers to perform basic study in animals and stimulate the progress of experimental otology which is in evolution.

[Reconstruction of the ear in the burns patient].

PubMed

Carrillo-Córdova, Jorge Raúl; Jiménez Murat, Yusef; Apellaniz-Campo, Armando; Bracho-Olvera, Hazel; Carrillo Esper, Raúl

Face burns are a singular pathology with great functional and psychological impact in the patients suffering them. The ears play a fundamental role in personal interactions and damage to this organ results in physical and emotional distress. The reconstructive treatment of the burned ear is a challenge. Multiple procedures have been described to achieve success in the reconstruction of the burned ear; immediate reconstruction with autologous rib cartilage, secondary reconstruction, alloplastic material reconstruction, tissue expansion, skin grafts and also microvascular flaps are some of the most common procedures used in this patients. All these techniques focus on giving a natural appearance to the patient. Burns to the ears affect 30% of the patients with facial burns, they require an excellent treatment given by a multidisciplinary team. Copyright © 2017 Academia Mexicana de Cirugía A.C. Publicado por Masson Doyma México S.A. All rights reserved.

Fgf8 and Fgf3 are required for zebrafish ear placode induction, maintenance and inner ear patterning.

PubMed

Léger, Sophie; Brand, Michael

2002-11-01

The vertebrate inner ear develops from initially 'simple' ectodermal placode and vesicle stages into the complex three-dimensional structure which is necessary for the senses of hearing and equilibrium. Although the main morphological events in vertebrate inner ear development are known, the genetic mechanisms controlling them are scarcely understood. Previous studies have suggested that the otic placode is induced by signals from the chordamesoderm and the hindbrain, notably by fibroblast growth factors (Fgfs) and Wnt proteins. Here we study the role of Fgf8 as a bona-fide hindbrain-derived signal that acts in conjunction with Fgf3 during placode induction, maintenance and otic vesicle patterning. Acerebellar (ace) is a mutant in the fgf8 gene that results in a non-functional Fgf8 product. Homozygous mutants for acerebellar (ace) have smaller ears that typically have only one otolith, abnormal semi-circular canals, and behavioral defects. Using gene expression markers for the otic placode, we find that ace/fgf8 and Fgf-signaling are required for normal otic placode formation and maintenance. Conversely, misexpression of fgf8 or Fgf8-coated beads implanted into the vicinity of the otic placode can increase ear size and marker gene expression, although competence to respond to the induction appears restricted. Cell transplantation experiments and expression analysis suggest that Fgf8 is required in the hindbrain in the rhombomere 4-6 area to restore normal placode development in ace mutants, in close neighbourhood to the forming placode, but not in mesodermal tissues. Fgf3 and Fgf8 are expressed in hindbrain rhombomere 4 during the stages that are critical for placode induction. Joint inactivation of Fgf3 and Fgf8 by mutation or antisense-morpholino injection causes failure of placode formation and results in ear-less embryos, mimicking the phenotype we observe after pharmacological inhibition of Fgf-signaling. Fgf8 and Fgf3 together therefore act during induction and differentiation of the ear placode. In addition to the early requirement for Fgf signaling, the abnormal differentiation of inner ear structures and mechanosensory hair cells in ace mutants, pharmacological inhibition of Fgf signaling, and the expression of fgf8 and fgf3 in the otic vesicle demonstrate independent Fgf function(s) during later development of the otic vesicle and lateral line organ. We furthermore addressed a potential role of endomesomerm by studying mzoep mutant embryos that are depleted of head endomesodermal tissue, including chordamesoderm, due to a lack of Nodal-pathway signaling. In these embryos, early placode induction proceeds largely normally, but the ear placode extends abnormally to midline levels at later stages, suggesting a role for the midline in restricting placode development to dorsolateral levels. We suggest a model of zebrafish inner ear development with several discrete steps that utilize sequential Fgf signals during otic placode induction and vesicle patterning. Copyright 2002 Elsevier Science Ireland Ltd.

QTL Mapping of Kernel Number-Related Traits and Validation of One Major QTL for Ear Length in Maize.

PubMed

Huo, Dongao; Ning, Qiang; Shen, Xiaomeng; Liu, Lei; Zhang, Zuxin

2016-01-01

The kernel number is a grain yield component and an important maize breeding goal. Ear length, kernel number per row and ear row number are highly correlated with the kernel number per ear, which eventually determines the ear weight and grain yield. In this study, two sets of F2:3 families developed from two bi-parental crosses sharing one inbred line were used to identify quantitative trait loci (QTL) for four kernel number-related traits: ear length, kernel number per row, ear row number and ear weight. A total of 39 QTLs for the four traits were identified in the two populations. The phenotypic variance explained by a single QTL ranged from 0.4% to 29.5%. Additionally, 14 overlapping QTLs formed 5 QTL clusters on chromosomes 1, 4, 5, 7, and 10. Intriguingly, six QTLs for ear length and kernel number per row overlapped in a region on chromosome 1. This region was designated qEL1.10 and was validated as being simultaneously responsible for ear length, kernel number per row and ear weight in a near isogenic line-derived population, suggesting that qEL1.10 was a pleiotropic QTL with large effects. Furthermore, the performance of hybrids generated by crossing 6 elite inbred lines with two near isogenic lines at qEL1.10 showed the breeding value of qEL1.10 for the improvement of the kernel number and grain yield of maize hybrids. This study provides a basis for further fine mapping, molecular marker-aided breeding and functional studies of kernel number-related traits in maize.

Generation and characterization of Atoh1-Cre knock-in mouse line

PubMed Central

Yang, Hua; Xie, Xiaoling; Deng, Min; Chen, Xiaowei; Gan, Lin

2010-01-01

Summary Atoh1 encodes a basic helix-loop-helix (bHLH) transcription factor required for the development of the inner ear sensory epithelia, the dorsal spinal cord, brainstem, cerebellum, and intestinal secretory cells. In this study to create a genetic tool for the research on gene function in the ear sensory organs, we generated an Atoh1-Cre knock-in mouse line by replacing the entire Atoh1 coding sequences with the Cre coding sequences. Atoh1Cre/+mice were viable, fertile, and displayed no visible defects whereas the Atoh1Cre/Cremice died perinatally. The spatiotemporal activities of Cre recombinase were examined by crossing Atoh1-Cre mice with the R26R-lacZ conditional reporter mice. Atoh1-Cre activities were detected in the developing inner ear, the hindbrain, the spinal cord, and the intestine. In the inner ear, Atoh1-Cre activities were confined to the sensory organs in which lacZ expression is detected in nearly all of the hair cells and in many supporting cells. Thus, Atoh1-Cre mouse line serves as a useful tool for the functional study of genes in the inner ear. In addition, our results demonstrate that Atoh1 is expressed in the common progenitors destined for both hair and supporting cells. PMID:20533400

Limits on normal cochlear 'third' windows provided by previous investigations of additional sound paths into and out of the cat inner ear.

PubMed

Rosowski, John J; Bowers, Peter; Nakajima, Hideko H

2018-03-01

While most models of cochlear function assume the presence of only two windows into the mammalian cochlea (the oval and round windows), a position that is generally supported by several lines of data, there is evidence for additional sound paths into and out of the inner ear in normal mammals. In this report we review the existing evidence for and against the 'two-window' hypothesis. We then determine how existing data and inner-ear anatomy restrict transmission of sound through these additional sound pathways in cat by utilizing a well-tested model of the cat inner ear, together with anatomical descriptions of the cat cochlear and vestibular aqueducts (potential additional windows to the cochlea). We conclude: (1) The existing data place limits on the size of the cochlear and vestibular aqueducts in cat and are consistent with small volume-velocities through these ducts during ossicular stimulation of the cochlea, (2) the predicted volume velocities produced by aqueducts with diameters half the size of the bony diameters match the functional data within ±10 dB, and (3) these additional volume velocity paths contribute to the inner ear's response to non-acoustic stimulation and conductive pathology. Copyright © 2017 Elsevier B.V. All rights reserved.

VEGF-C gene therapy augments postnatal lymphangiogenesis and ameliorates secondary lymphedema

PubMed Central

Yoon, Young-sup; Murayama, Toshinori; Gravereaux, Edwin; Tkebuchava, Tengiz; Silver, Marcy; Curry, Cynthia; Wecker, Andrea; Kirchmair, Rudolf; Hu, Chun Song; Kearney, Marianne; Ashare, Alan; Jackson, David G.; Kubo, Hajime; Isner, Jeffrey M.; Losordo, Douglas W.

2003-01-01

Although lymphedema is a common clinical condition, treatment for this disabling condition remains limited and largely ineffective. Recently, it has been reported that overexpression of VEGF-C correlates with increased lymphatic vessel growth (lymphangiogenesis). However, the effect of VEGF-C–induced lymphangiogenesis on lymphedema has yet to be demonstrated. Here we investigated the impact of local transfer of naked plasmid DNA encoding human VEGF-C (phVEGF-C) on two animal models of lymphedema: one in the rabbit ear and the other in the mouse tail. In a rabbit model, following local phVEGF-C gene transfer, VEGFR-3 expression was significantly increased. This gene transfer led to a decrease in thickness and volume of lymphedema, improvement of lymphatic function demonstrated by serial lymphoscintigraphy, and finally, attenuation of the fibrofatty changes of the skin, the final consequences of lymphedema. The favorable effect of phVEGF-C on lymphedema was reconfirmed in a mouse tail model. Immunohistochemical analysis using lymphatic-specific markers: VEGFR-3, lymphatic endothelial hyaluronan receptor-1, together with the proliferation marker Ki-67 Ab revealed that phVEGF-C transfection potently induced new lymphatic vessel growth. This study, we believe for the first time, documents that gene transfer of phVEGF-C resolves lymphedema through direct augmentation of lymphangiogenesis. This novel therapeutic strategy may merit clinical investigation in patients with lymphedema. PMID:12618526

[Severe Bleeding from the Middle Ear Cavity after Myringotomy: Review Based on a Case Report].

PubMed

Hofmann, Veit M; Niehues, Stefan M; Albers, Andreas E; Pudszuhn, Annett

2017-03-01

Report of a rare case of severe bleeding from the middle ear cavity after myringotomy. On the basis of the case report, the procedure for such bleeding is discussed in the context of the literature. A 6-year-old boy received a revision myringotomy in an ambulant setting. During the procedure a severe bleeding occurred. The external auditory canal was adequately packed. The patient was extubated and transferred to the clinic as an emergency. Computer tomography of the temporal bone showed the anatomical variant of a dehiscent high jugular bulb, which had been injured. Because no rebleeding occurred, the packing of the ear canal was removed and an explorative tympanoscopy was performed on the third postoperative day. When the tympanomeatal flap was lifted, the defect in the jugular bulb was found. The lesion was covered with Tutopatch ® pads and fibrin glue and the auditory canal was packed again. After removal of the packing three weeks postoperatively a properly healed situs was found. No further measures were taken. The injury of a dehiscent jugular bulb in the course of ear surgeries leads to a massive hemorrhage. The case describes the diagnostic and therapeutic procedure for this relatively rare but severe complication. © Georg Thieme Verlag KG Stuttgart · New York.

Cell-free extract from porcine induced pluripotent stem cells can affect porcine somatic cell nuclear reprogramming.

PubMed

No, Jin-Gu; Choi, Mi-Kyung; Kwon, Dae-Jin; Yoo, Jae Gyu; Yang, Byoung-Chul; Park, Jin-Ki; Kim, Dong-Hoon

2015-01-01

Pretreatment of somatic cells with undifferentiated cell extracts, such as embryonic stem cells and mammalian oocytes, is an attractive alternative method for reprogramming control. The properties of induced pluripotent stem cells (iPSCs) are similar to those of embryonic stem cells; however, no studies have reported somatic cell nuclear reprogramming using iPSC extracts. Therefore, this study aimed to evaluate the effects of porcine iPSC extracts treatment on porcine ear fibroblasts and early development of porcine cloned embryos produced from porcine ear skin fibroblasts pretreated with the porcine iPSC extracts. The Chariot(TM) reagent system was used to deliver the iPSC extracts into cultured porcine ear skin fibroblasts. The iPSC extracts-treated cells (iPSC-treated cells) were cultured for 3 days and used for analyzing histone modification and somatic cell nuclear transfer. Compared to the results for nontreated cells, the trimethylation status of histone H3 lysine residue 9 (H3K9) in the iPSC-treated cells significantly decreased. The expression of Jmjd2b, the H3K9 trimethylation-specific demethylase gene, significantly increased in the iPSC-treated cells; conversely, the expression of the proapoptotic genes, Bax and p53, significantly decreased. When the iPSC-treated cells were transferred into enucleated porcine oocytes, no differences were observed in blastocyst development and total cell number in blastocysts compared with the results for control cells. However, H3K9 trimethylation of pronuclear-stage-cloned embryos significantly decreased in the iPSC-treated cells. Additionally, Bax and p53 gene expression in the blastocysts was significantly lower in iPSC-treated cells than in control cells. To our knowledge, this study is the first to show that an extracts of porcine iPSCs can affect histone modification and gene expression in porcine ear skin fibroblasts and cloned embryos.

The comparative anatomy of the pig middle ear cavity: a model for middle ear inflammation in the human?

PubMed Central

PRACY, J. P.; WHITE, A.; MUSTAFA, Y.; SMITH, D.; PERRY, M. E.

1998-01-01

This study was undertaken to develop a functional model of otitis media with effusion (OME) in the pig (Sus scrofa), with the purpose of investigating the origin of lymphocytes populating the middle ear during the course of an inflammatory process. The relevance of the model to the human condition of OME is to a large extent dependent on the anatomical and physiological similarities between the middle ear cavity and the pharyngeal lymphoid tissue of the pig and man. Anatomical specimens were collected from 7 young Large White pigs to determine the gross anatomy of the middle ear cavity and the histological characteristics of the middle ear mucosa. It was found that the anatomy of the 3 parts of the middle ear cavity in man and in the pig is broadly similar, although some minor differences were observed. The porcine eustachian tube was seen to be cartilaginous throughout its length in contrast to the part osseous, part cartilaginous structure found in man; the porcine ossicles were slightly different in shape to those of man and the air cell system was situated inferior to the tympanic cavity in the pig as opposed to posteriorly in man. This paper describes the structure and morphology of the pig middle ear cavity and compares and contrasts it with that of man. The minor differences observed are of anatomical importance but do not diminish the usefulness of the pig middle ear cleft as a potential model for human middle ear disorders. PMID:9688502

Vestibular-evoked myogenic potentials, clinical evaluation, and imaging findings in multiple sclerosis.

PubMed

Güven, Hayat; Bayır, Omer; Aytaç, Emrah; Ozdek, Ali; Comoğlu, Selim Selçuk; Korkmaz, Hakan

2014-02-01

Vestibular-evoked myogenic potentials (VEMP), short-latency electromyographic responses elicited by acoustic stimuli, evaluate the function of vestibulocollic reflex and may give information about brainstem function. The aim of the present study is to evaluate the potential contribution of VEMP to the diagnosis of multiple sclerosis (MS). Fifty patients with MS and 30 healthy control subjects were included in this study. The frequency of VEMP p1-n1 and n2-p2 waves; mean p1, n1, n2, and p2 latency; and mean p1-n1 and n2-p2 amplitude were determined. The relation between clinical and imaging findings and VEMP parameters was evaluated. The p1-n1 and n2-p2 waves were more frequently absent in MS than in control subjects [p1-n1 wave absent: MS, 25 (25 %) ears; control, 6 (10 %) ears; P ≤ 0.02] [n2-p2 wave absent: MS, 44 (44 %) ears; control, 7 (12 %) ears; P ≤ 0.001]. The mean p1-n1 amplitude was lower in MS than in control subjects (MS, 19.1 ± 7.2 μV; control, 23.3 ± 7.4 μV; P ≤ 0.002). A total of 24/50 (48 %) MS patients had VEMP abnormalities (absent responses and/or prolonged latencies). VEMP abnormalities were more frequent in patients with than without vestibular symptoms (P ≤ 0.02) and with brainstem functional system score (FSS) ≥ 1 than FSS = 0 (P ≤ 0.02). In patients with MS, absence of p1-n1 wave was more frequent in patients with than without vestibular symptoms [absence of p1-n1 wave: vestibular symptoms, 9 (45 %) ears; no vestibular symptoms, 16 (20 %) ears; P ≤ 0.03] and patients with Expanded Disability Status Scale (EDSS) score ≥ 5.5 [absence of p1-n1 wave: EDSS ≥ 5.5, 7 (70 %) ears; EDSS <5.5, 18 (20 %) ears; P ≤ 0.001]. Abnormal VEMP may be noted in MS patients, especially those with vestibular symptoms and greater disability. The VEMP test may complement other studies for diagnosis and follow-up of patients with MS.

Numerical calculation of listener-specific head-related transfer functions and sound localization: Microphone model and mesh discretization

PubMed Central

Ziegelwanger, Harald; Majdak, Piotr; Kreuzer, Wolfgang

2015-01-01

Head-related transfer functions (HRTFs) can be numerically calculated by applying the boundary element method on the geometry of a listener’s head and pinnae. The calculation results are defined by geometrical, numerical, and acoustical parameters like the microphone used in acoustic measurements. The scope of this study was to estimate requirements on the size and position of the microphone model and on the discretization of the boundary geometry as triangular polygon mesh for accurate sound localization. The evaluation involved the analysis of localization errors predicted by a sagittal-plane localization model, the comparison of equivalent head radii estimated by a time-of-arrival model, and the analysis of actual localization errors obtained in a sound-localization experiment. While the average edge length (AEL) of the mesh had a negligible effect on localization performance in the lateral dimension, the localization performance in sagittal planes, however, degraded for larger AELs with the geometrical error as dominant factor. A microphone position at an arbitrary position at the entrance of the ear canal, a microphone size of 1 mm radius, and a mesh with 1 mm AEL yielded a localization performance similar to or better than observed with acoustically measured HRTFs. PMID:26233020

Modeling the direction-continuous time-of-arrival in head-related transfer functions

PubMed Central

Ziegelwanger, Harald; Majdak, Piotr

2015-01-01

Head-related transfer functions (HRTFs) describe the filtering of the incoming sound by the torso, head, and pinna. As a consequence of the propagation path from the source to the ear, each HRTF contains a direction-dependent, broadband time-of-arrival (TOA). TOAs are usually estimated independently for each direction from HRTFs, a method prone to artifacts and limited by the spatial sampling. In this study, a continuous-direction TOA model combined with an outlier-removal algorithm is proposed. The model is based on a simplified geometric representation of the listener, and his/her arbitrary position within the HRTF measurement. The outlier-removal procedure uses the extreme studentized deviation test to remove implausible TOAs. The model was evaluated for numerically calculated HRTFs of sphere, torso, and pinna under various conditions. The accuracy of estimated parameters was within the resolution given by the sampling rate. Applied to acoustically measured HRTFs of 172 listeners, the estimated parameters were consistent with realistic listener geometry. The outlier removal further improved the goodness-of-fit, particularly for some problematic fits. The comparison with a simpler model that fixed the listener position to the center of the measurement geometry showed a clear advantage of listener position as an additional free model parameter. PMID:24606268

Effects of eye-glasses, hair, headgear, and clothing on measured head-related transfer functions Part Ib

NASA Astrophysics Data System (ADS)

Riederer, Klaus A. J.

2003-10-01

Extensive head-related transfer function (HRTF) measurements show high HRTF repeatability, consequences of different measurement methods, and conditions covering the whole three-dimensional space [Riederer, J. Audio Eng. Soc. (Abstracts) 46, 1036 (1998), preprint 4846]. This study concentrates on specific effects on HRTFs carefully re-measured on the same Cortex dummy head applying Sennheiser KE4-211-2 microphones at its silicone putty blocked ear-canal entrances, employing 252 sound incidents including seven elevations. The effects of five different wigs (synthetic, natural, thick, thin, long and short hair) with varied hairstyles, four hats (cap, bicycle helmet, mens and womens trilby), clothes (alpaca pullover, bicycling drymax-jacket) and spectacles were investigated under 28 combinations. The influences are highly dependent on direction, frequency, and case. Clothes and eye-glasses affect minimally HRTF; hair has a stronger effect, depending on the actual hairdo (typically above 7 kHz). Hats alter intensively HRTFs (typically above 5 kHz), depending on the model. The measurements give deeper insight to the development of idiosyncratic features in binaural localization cues. The second part of the study addresses their perceptual effects [Riederer, J. Acoust. Soc. Am., this issue]. [Work supported by Graduate School of Electronics, Telecommunication and Automation; thanks to Finnish Broadcasting Company, Mr. Hellstrom; Mrs. Chen.

15 CFR 762.2 - Records to be retained.

Code of Federal Regulations, 2014 CFR

2014-01-01

... prior approval on a BIS or DDTC license (STA). (c) Special recordkeeping requirement—(1) Libya. Persons... Control (OFAC) for the export to Libya of any item subject to the EAR must maintain a record of those items transferred to Libya pursuant to such specific license and record when the items are consumed or...

Sensory Cells of the Fish Ear: A Hairy Enigma

NASA Technical Reports Server (NTRS)

Popper, A. N.; Saidel, W. M.

1995-01-01

Analysis of the structure of the ears in teleost fishes has led to the tentative suggestion that otolithic endorgans may function differently, in different species. Recently, evidence has demonstrated different 'types' of sensory hair cells can be found in the ears of teleost fishes, and individual hair cell types are found in discrete regions of individual sensory, epithelia. The presence of multiple hair cell types in fishes provides strong support to the hypothesis of regional differences in the responses of individual otolithic sensory epithelia. The finding of hair cell types in fishes that closely resemble those found in amniote vestibular endorgans also suggests that hair cell heterogeneity arose earlier in the evolution of the vertebrate ear than previously thought.

The Severity of Vestibular Dysfunction in Deafness as a Determinant of Comorbid Hyperactivity or Anxiety

PubMed Central

McKeehan, Nicholas

2017-01-01

Attention-deficit/hyperactivity disorder (ADHD) and anxiety-related disorders occur at rates 2–3 times higher in deaf compared with hearing children. Potential explanations for these elevated rates and the heterogeneity of behavioral disorders associated with deafness have usually focused on socio-environmental rather than biological effects. Children with the 22q11.2 deletion or duplication syndromes often display hearing loss and behavioral disorders, including ADHD and anxiety-related disorders. Here, we show that mouse mutants with either a gain or loss of function of the T-Box transcription factor gene, Tbx1, which lies within the 22q11.2 region and is responsible for most of the syndromic defects, exhibit inner ear defects and hyperactivity. Furthermore, we show that (1) inner ear dysfunction due to the tissue-specific loss of Tbx1 or Slc12a2, which encodes a sodium-potassium-chloride cotransporter and is also necessary for inner ear function, causes hyperactivity; (2) vestibular rather than auditory failure causes hyperactivity; and (3) the severity rather than the age of onset of vestibular dysfunction differentiates whether hyperactivity or anxiety co-occurs with inner ear dysfunction. Together, these findings highlight a biological link between inner ear dysfunction and behavioral disorders and how sensory abnormalities can contribute to the etiology of disorders traditionally considered of cerebral origin. SIGNIFICANCE STATEMENT This study examines the biological rather than socio-environmental reasons why hyperactivity and anxiety disorders occur at higher rates in deaf individuals. Using conditional genetic approaches in mice, the authors show that (1) inner ear dysfunction due to either Tbx1 or Slc12a2 mutations cause hyperactivity; (2) it is vestibular dysfunction, which frequently co-occurs with deafness but often remains undiagnosed, rather than auditory dysfunction that causes hyperactivity and anxiety-related symptoms; and (3) the severity of vestibular dysfunction can predict whether hyperactivity or anxiety coexist with inner ear dysfunction. These findings suggest a need to evaluate vestibular function in hearing impaired individuals, especially those who exhibit hyperactive and anxiety-related symptoms. PMID:28438970

The Severity of Vestibular Dysfunction in Deafness as a Determinant of Comorbid Hyperactivity or Anxiety.

PubMed

Antoine, Michelle W; Vijayakumar, Sarath; McKeehan, Nicholas; Jones, Sherri M; Hébert, Jean M

2017-05-17

Attention-deficit/hyperactivity disorder (ADHD) and anxiety-related disorders occur at rates 2-3 times higher in deaf compared with hearing children. Potential explanations for these elevated rates and the heterogeneity of behavioral disorders associated with deafness have usually focused on socio-environmental rather than biological effects. Children with the 22q11.2 deletion or duplication syndromes often display hearing loss and behavioral disorders, including ADHD and anxiety-related disorders. Here, we show that mouse mutants with either a gain or loss of function of the T-Box transcription factor gene, Tbx1 , which lies within the 22q11.2 region and is responsible for most of the syndromic defects, exhibit inner ear defects and hyperactivity. Furthermore, we show that (1) inner ear dysfunction due to the tissue-specific loss of Tbx1 or Slc12a2 , which encodes a sodium-potassium-chloride cotransporter and is also necessary for inner ear function, causes hyperactivity; (2) vestibular rather than auditory failure causes hyperactivity; and (3) the severity rather than the age of onset of vestibular dysfunction differentiates whether hyperactivity or anxiety co-occurs with inner ear dysfunction. Together, these findings highlight a biological link between inner ear dysfunction and behavioral disorders and how sensory abnormalities can contribute to the etiology of disorders traditionally considered of cerebral origin. SIGNIFICANCE STATEMENT This study examines the biological rather than socio-environmental reasons why hyperactivity and anxiety disorders occur at higher rates in deaf individuals. Using conditional genetic approaches in mice, the authors show that (1) inner ear dysfunction due to either Tbx1 or Slc12a2 mutations cause hyperactivity; (2) it is vestibular dysfunction, which frequently co-occurs with deafness but often remains undiagnosed, rather than auditory dysfunction that causes hyperactivity and anxiety-related symptoms; and (3) the severity of vestibular dysfunction can predict whether hyperactivity or anxiety coexist with inner ear dysfunction. These findings suggest a need to evaluate vestibular function in hearing impaired individuals, especially those who exhibit hyperactive and anxiety-related symptoms. Copyright © 2017 the authors 0270-6474/17/375144-11$15.00/0.

Continuous long-term measurements of the middle ear pressure in subjects without a history of ear disease.

PubMed

Tideholm, B; Carlborg, B; Jönsson, S; Bylander-Groth, A

1998-06-01

A new method was used for continuous measurement of the middle ear (ME) pressure during a 24-h period. In 10 subjects without a history of ear disease a small perforation was made through the tympanic membrane. A tight rubber stopper containing a small polyethylene tube was fitted into the external ear canal. Conventional tubal function tests were performed. The equipment was then carried by the subjects for 24 h of normal activity to monitor any slow or rapid dynamic pressure change in the ME. Body position was found to be the most important factor affecting ME pressure variation, during the 24-h continuous pressure measurements. A significant pressure rise occurred in the recumbent position in all but one subject. Few rapid pressure equilibrations were seen during the recordings, indicating few tubal openings. This implies that the pressure changes in the ME seen in this study were mainly the result of gas exchange over the mucosa. The investigation might be a base for reference when investigating different kinds of pathologic conditions in the ear.

Metabolomic profiling in inner ear fluid by gas chromatography/mass spectrometry in guinea pig cochlea.

PubMed

Fujita, Takeshi; Yamashita, Daisuke; Irino, Yasuhiro; Kitamoto, Junko; Fukuda, Yuriko; Inokuchi, Go; Hasegawa, Shingo; Otsuki, Naoki; Yoshida, Masaru; Nibu, Ken-ichi

2015-10-08

The composition and homeostasis of inner ear fluids are important in hearing function. The purpose of this study was to perform metabolomic analysis of the inner ear fluid in guinea pig cochlea, which has not been previously reported in literature, using gas chromatography/mass spectrometry (GC/MS). Seventy-seven kinds of metabolites were detected in the inner ear fluid. Six metabolites, ascorbic acid, fructose, galactosamine, inositol, pyruvate+oxaloacetic acid, and meso-erythritol, were significantly more abundant, and nine metabolites, phosphate, valine, glycine, glycerol, ornithine, glucose, citric acid+isocitric acid, mannose, and trans-4-hydroxy-L-proline, were less abundant in the inner ear fluid than in plasma. The levels of ten metabolites, 3-hydroxy-butyrate, glycerol, fumaric acid, galactosamine, pyruvate+oxaloacetic acid, phosphate, meso-erythritol, citric acid+isocitric acid, mannose, and inositol, in the inner ear fluid significantly changed after loud noise exposure. These observations may help to elucidate various clinical conditions of sensorineural hearing loss, including noise-induced hearing loss. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

Effects of Smoking on Eustachian Tube and Hearing.

PubMed

Pezzoli, Matteo; Lofaro, Denise; Oliva, Alessandro; Orione, Monica; Cupi, Daniela; Albera, Andrea; Bongioannini, Guido; Albera, Roberto

2017-12-01

The purpose of this study was to evaluate the effect of tobacco use on the Eustachian tube and inner ear function. Case-control study. Thirty-one nonsmoking volunteers and 34 smoking subjects recruited in an University Hospital, submitted to an audiological evaluation including pure tone audiometry, basal tympanogram, stapedial reflexes analysis, and nine-step eustachian tube (ET) function test. Pure Tone Average (PTA) threshold at all frequencies tested was 12.5 dB in smokers and 3.7 in nonsmoking subjects. Nine smokers (27%) presented some degree of hearing loss versus none in the nonsmoker group. Linear regression analysis showed a higher degree of sensorineural hearing loss with age in smokers. Among the smokers, 20 subjects (59%) presented an impaired tubal function for the nine-step inflation/deflation tympanometric test, while only 6 (19%) subjects in the group of nonsmokers showed a tubal dysfunction. Tobacco use may reduce the ability to hear, mainly causing a sensorineural hearing loss for higher frequencies. We also found the presence of a high number of smokers suffering from tubal dysfunction. This has an important clinical relevance, not only because smoking increases the incidence of middle ear diseases, but also because tubal dysfunction may cause nonspecific symptoms characterised by ear fullness and difficulties in middle ear equalisation.

Mass distribution and rotational inertia of "microtype" and "freely mobile" middle ear ossicles in rodents.

PubMed

Lavender, Danielle; Taraskin, Sergei N; Mason, Matthew J

2011-12-01

The middle ears of seven species of rodents, including four hamster species, were examined under light microscopy and through micro-CT imaging. Hamsters were found to possess a spectrum of ossicular morphologies ranging from something approaching "freely mobile" (Mesocricetus) to something nearer the "microtype" (Cricetulus), although no hamster has an orbicular apophysis of the malleus. Rats, mice and Calomyscus were found to have typically microtype ossicles. To explore the functional effects of these morphological differences, CT scan data were used to calculate the magnitudes of the moments of inertia and positions of the centres of mass and principal rotational axes for the malleus-incus complexes. Microtype species were found to have much greater ossicular inertias, relative to size, about the "anatomical axis" extending between anterior process of the malleus and short process of the incus; ossicular centres of mass were displaced further from this axis. Calculated inertial values were then put into an existing model of middle ear function (Hemilä et al., 1995), in order to see whether the more accurate data would improve predictions of upper hearing limits. For the rat and mouse they did, but this was not so for the hamster Mesocricetus. This might indicate that the inner rather than the middle ear limits hearing in this species, or might simply reflect other shortcomings of the model. Functional differences appear to exist even among rodent ears of the same general type, but the adaptive significance of these differences remains enigmatic. Copyright © 2011 Elsevier B.V. All rights reserved.

Long-Term Effects of Otitis Media a Ten-Year Cohort Study of Alaskan Eskimo Children

ERIC Educational Resources Information Center

Kaplan, Gary J.; And Others

1973-01-01

Histories of ear disease, otoscopic examinations, and audiologic, intelligence, and achievement tests were obtained from a cohort of 489 Alaskan Eskimo children, followed through the first 10 years of life, to determine whether otitis media (middle ear inflammation) deleteriously affected intellectual functioning and achievement in school.…

Local gene therapy durably restores vestibular function in a mouse model of Usher syndrome type 1G.

PubMed

Emptoz, Alice; Michel, Vincent; Lelli, Andrea; Akil, Omar; Boutet de Monvel, Jacques; Lahlou, Ghizlene; Meyer, Anaïs; Dupont, Typhaine; Nouaille, Sylvie; Ey, Elody; Franca de Barros, Filipa; Beraneck, Mathieu; Dulon, Didier; Hardelin, Jean-Pierre; Lustig, Lawrence; Avan, Paul; Petit, Christine; Safieddine, Saaid

2017-09-05

Our understanding of the mechanisms underlying inherited forms of inner ear deficits has considerably improved during the past 20 y, but we are still far from curative treatments. We investigated gene replacement as a strategy for restoring inner ear functions in a mouse model of Usher syndrome type 1G, characterized by congenital profound deafness and balance disorders. These mice lack the scaffold protein sans, which is involved both in the morphogenesis of the stereociliary bundle, the sensory antenna of inner ear hair cells, and in the mechanoelectrical transduction process. We show that a single delivery of the sans cDNA by the adenoassociated virus 8 to the inner ear of newborn mutant mice reestablishes the expression and targeting of the protein to the tips of stereocilia. The therapeutic gene restores the architecture and mechanosensitivity of stereociliary bundles, improves hearing thresholds, and durably rescues these mice from the balance defects. Our results open up new perspectives for efficient gene therapy of cochlear and vestibular disorders by showing that even severe dysmorphogenesis of stereociliary bundles can be corrected.

Surgical anatomy and pathology of the middle ear.

PubMed

Luers, Jan Christoffer; Hüttenbrink, Karl-Bernd

2016-02-01

Middle ear surgery is strongly influenced by anatomical and functional characteristics of the middle ear. The complex anatomy means a challenge for the otosurgeon who moves between preservation or improvement of highly important functions (hearing, balance, facial motion) and eradication of diseases. Of these, perforations of the tympanic membrane, chronic otitis media, tympanosclerosis and cholesteatoma are encountered most often in clinical practice. Modern techniques for reconstruction of the ossicular chain aim for best possible hearing improvement using delicate alloplastic titanium prostheses, but a number of prosthesis-unrelated factors work against this intent. Surgery is always individualized to the case and there is no one-fits-all strategy. Above all, both middle ear diseases and surgery can be associated with a number of complications; the most important ones being hearing deterioration or deafness, dizziness, facial palsy and life-threatening intracranial complications. To minimize risks, a solid knowledge of and respect for neurootologic structures is essential for an otosurgeon who must train him- or herself intensively on temporal bones before performing surgery on a patient. © 2015 Anatomical Society.

Missing links in some curious auditory phenomena: a tale from the middle ear.

PubMed

Carpenter, Michelle S; Cacace, Anthony T; Mahoney, Marty J

2012-02-01

Broadband middle ear power reflectance (BMEPR) is an emerging noninvasive electroacoustic measure that evaluates transmission/reflection properties of the middle ear in high resolution. It is applicable over the entire age continuum and is rapid to perform. However, it remains to be determined if BMEPR is just an incremental step in the evolution of middle ear assessment or a major advance in the way middle ear function can be evaluated. To evaluate effects of age, gender, ear, and frequency on BMEPR measurements in adults without a history of middle ear disease and to assess whether these factors require consideration in test development; to review how these data may influence active physiologic process within the inner ear; to consider how they reconcile with previously published results; and to suggest applications for future research. Prospective, cross-sectional, multivariate analysis to evaluate the effects of age, gender, ear, and frequency on BMEPR in humans without a history of middle ear disease and no air-bone gaps exceeding 10 dB for any frequency. Fifty-six adults in two age groups (Group 1: 18-25 yr, n = 28; Group 2: ≥50 and <66 yr, n = 28). Each age group was stratified by ear and gender in a balanced design. Pure tone air conduction and bone-conduction audiometry was conducted in a commercial sound booth, using a clinical audiometer with standard earphones enclosed in supra-aural ear cushions, and a standard bone-conduction oscillator and headband to evaluate for air-bone gaps. Broadband middle ear power reflectance was measured using a calibrated, commercially available computer-controlled system that incorporated a high quality probe assembly to transduce stimuli and record acoustic responses from the ear canal. Data were analyzed with a four-way (2 × 2 × 2 × 16) repeated measures analysis-of-variance (ANOVA) to evaluate the effects of age group (young vs. old), gender (male vs. female), ear (left vs. right), and frequency (258 to 5040 Hz) on BMEPR. The ANOVA revealed a significant main effect of frequency. There were also gender × ear, gender × frequency, and age × gender × ear interactions. The three-way, age × gender × ear interaction captured the essence of results and revealed lowest power reflectance values in younger females and for right ears. This trend partially reversed in the older age group where higher power reflectance values were observed only in right ears of older females. The significant effects of age, gender, ear, and frequency on BMEPR parallel ear- and gender-related differences in hearing sensitivity, ear, and gender differences in the prevalence of spontaneous otoacoustic emissions (OAEs), gender differences in the magnitude of transient evoked OAEs, and ear differences in transient evoked contralateral OAE suppression effects reported in the literature. While original discussions of these aforementioned effects focused primarily on endocochlear and olivocochlear mechanisms, the BMEPR measurements reported herein suggest that middle ear transmission characteristics may also play a role. American Academy of Audiology.

[Temporal rotation skin flap combined with cartilage plasty for correcting cryptotia].

PubMed

Li, Gaofeng; Luo, Tao; Ding, Wei; Ouyang, Huawei; Liu, Wanli; Tan, Jun

2014-01-01

To explore the therapeutic effect of the temporal rotation flap combined with cartilage plasty for cryptotia correction. From January 2009 to June 2012, 8 cases with cryptotia (10 ears) were treated. After complete dissection of the cartilage adhesion, the cartilage was reshaped by suture to restore its appearance. Then the temporal triangular rotation flap was transferred to cover the wound. No hematoma, infection or flap necrosis happened. The follow-up period ranged from 3 months to 1 year, with an average of (6.88 +/- 2.85) months. The ear appearance kept stable with no recurrence and inconspicuous scar. Satisfactory result was achieved. Temporal rotation flap combined with cartilage plasty is a good option for correction of mild or moderate cryptotia.

Free gracilis transfer for smile in children: the Massachusetts Eye and Ear Infirmary Experience in excursion and quality-of-life changes.

PubMed

Hadlock, Tessa A; Malo, Juan S; Cheney, Mack L; Henstrom, Douglas K

2011-01-01

Free muscle transfer for facial reanimation has become the standard of care in recent decades and is now the cornerstone intervention for dynamic smile reanimation. We sought to quantify smile excursion and quality-of-life (QOL) changes in our pediatric free gracilis recipients following reanimation. We quantified gracilis muscle excursion in 17 pediatric patients undergoing 19 consecutive pediatric free gracilis transplantation operations, using our validated SMILE program, as an objective measure of functional outcome. These were compared against excursion measured the same way in a cohort of 17 adults with 19 free gracilis operations. In addition, we prospectively evaluated QOL outcomes in these children using the Facial Clinimetric Evaluation (FaCE) instrument. The mean gracilis excursion in our pediatric free gracilis recipients was 8.8 mm ± 5.0 mm, which matched adult results, but with fewer complete failures of less than 2-mm excursion, with 2 (11%) and 4 (21%), respectively. Quality-of-life measures indicated statistically significant improvements following dynamic smile reanimation (P = .01). Dynamic facial reanimation using free gracilis transfer in children has an acceptable success rate, yields improved commissure excursion, and improves QOL in the pediatric population. It should be considered first-line therapy for children with lack of a meaningful smile secondary to facial paralysis.

Oral pseudoephedrine decreases the rate of transmucosal nitrous oxide exchange for the middle ear.

PubMed

Teixeira, Miriam S; Alper, Cuneyt M; Martin, Brian S; Doyle, Brendan M Cullen; Doyle, William J

2015-09-01

Determine if oral treatment with a vasoconstrictor decreases the blood to middle ear exchange rate of the perfusion-limited gas, nitrous oxide (N2O). Randomized, double-blind, crossover study. Ten adult subjects with and 10 without past middle ear disease completed paired experimental sessions, identical except for oral treatment with either pseudoephedrine hydrochloride or lactose placebo. At each session, subjects were fitted with a nonrebreathing mask and breathed room air for 20 minutes (acclimation period), 50% N2O:50% O2 for 20 minutes (experimental period), and 100% O2 for 10 minutes (recovery period). Throughout, heart rate, blood pressure, and O2 saturation were monitored, and bilateral middle ear pressures were recorded by tympanometry every minute. The primary outcome was the slope of the middle ear pressure-time function for the experimental period, which estimates the volume N2O exchange rate. Using repeated measures analysis of variance, the effects of group (disease history), treatment (active vs. placebo), and period (1 vs. 2) on the recorded vital signs, and of group, treatment, and ear (left/right) on the middle ear pressure-time slope were evaluated for statistical significance. Statistically significant effects of period on O2 saturation (period 2 > period 1) and of treatment on heart rate (active > placebo) were documented. Only treatment was statistically significant for the middle ear pressure-time slope, with a shallower slope characterizing the active treatment session. The volume exchange rate across the middle ear mucosa of perfusion-limited gases can be modulated pharmacologically. Theoretically, similar drugs can be used to reduce the requisite eustachian tube opening efficiency for adequate middle ear pressure regulation. 1b. © 2015 The American Laryngological, Rhinological and Otological Society, Inc.

Oral Pseudoephedrine Decreases the Rate of Trans-mucosal Nitrous Oxide Exchange for the Middle Ear

PubMed Central

Teixeira, Miriam S.; Alper, Cuneyt M.; Martin, Brian S; Cullen Doyle, Brendan M.; Doyle, William J.

2015-01-01

Objective Determine if oral pretreatment with a vasoconstrictor decreases the blood to middle-ear exchange-rate of the perfusion-limited gas, Nitrous Oxide (N2O). Study Design Randomized, double-blind, crossover study. Methods Ten adult subjects with and 10 without past middle-ear disease completed paired experimental sessions, identical but for oral pretreatment with either pseudoephedrine HCL or lactose placebo. At each session, subjects were fitted with a non-rebreathing mask and breathed room air for 20 minutes (acclimation period), 50% N2O:50% O2 for 20 minutes (experimental period) and 100% O2 for 10 minutes (recovery period). Throughout, heart-rate, blood-pressure and O2 saturation were monitored and bilateral middle-ear pressures were recorded by tympanometry every minute. The primary outcome was the slope of the middle-ear pressure-time function for the experimental period which estimates the volume N2O exchange-rate. Using repeated measures ANOVA, the effects of Group (disease history), Treatment (active vs. placebo) and Period (1 vs. 2) on the recorded vital signs, and of Group, Treatment and Ear (left/right) on the middle-ear pressure-time slope were evaluated for statistical significance. Results Statistically significant effects of Period on O2 saturation (Period 2>Period 1) and of Treatment on heart-rate (Active>Placebo) were documented. Only Treatment was statistically significant for the middle-ear pressure-time slope with a shallower slope characterizing the active treatment session. Conclusion The volume exchange-rate across the middle-ear mucosa of perfusion-limited gases can be modulated pharmacologically. Theoretically, similar drugs can be used to reduce the requisite Eustachian tube opening efficiency for adequate middle-ear pressure regulation. PMID:26152838

Restriction fragment length polymorphism markers associated with silk maysin, antibiosis to corn earworm (Lepidoptera: Noctuidae) larvae, in a dent and sweet corn cross.

PubMed

Guo, B Z; Zhang, Z J; Li, R G; Widstrom, N W; Snook, M E; Lynch, R E; Plaisted, D

2001-04-01

Maysin, a C-glycosylflavone in maize silk, has insecticidal activity against corn earworm, Helicoverpa zea (Boddie), larvae. Sweet corn, Zea mays L., is a vulnerable crop to ear-feeding insects and requires pesticide protection from ear damage. This study was conducted to identify maize chromosome regions associated with silk maysin concentration and eventually to transfer and develop high silk maysin sweet corn lines with marker-assisted selection (MAS). Using an F2 population derived from SC102 (high maysin dent corn) and B31857 (low maysin sh2 sweet corn), we detected two major quantitative trait loci (QTL). It was estimated that 25.6% of the silk maysin variance was associated with segregation in the genomic region of npi286 (flanking to p1) on chromosome 1S. We also demonstrated that a1 on chromosome 3L had major contribution to silk maysin (accounted for 15.7% of the variance). Locus a1 has a recessive gene action for high maysin with the presence of functional p1 allele. Markers umc66a (near c2) and umc105a on chromosome 9S also were detected in this analysis with minor contribution. A multiple-locus model, which included npi286, a1, csu3 (Bin 1.05), umc245 (Bin 7.05), agrr21 (Bin 8.09), umc105a, and the epistatic interactions npi286 x a1, a1 x agrr21, csu3 x umc245, and umc105a x umc245, accounted for 76.3% of the total silk maysin variance. Tester crosses showed that at the a1 locus, SC102 has functional A1 alleles and B31857 has homozygous recessive a1 alleles. Individuals of (SC102 x B31857) x B31857 were examined with MAS and plants with p1 allele from SC102 and homozygous a1 alleles from B31857 had consistent high silk maysin. Marker-assisted selection seems to be a suitable method to transfer silk maysin to sweet corn lines to reduce pesticide application.

Non-invasive biophysical measurement of travelling waves in the insect inner ear

PubMed Central

2017-01-01

Frequency analysis in the mammalian cochlea depends on the propagation of frequency information in the form of a travelling wave (TW) across tonotopically arranged auditory sensilla. TWs have been directly observed in the basilar papilla of birds and the ears of bush-crickets (Insecta: Orthoptera) and have also been indirectly inferred in the hearing organs of some reptiles and frogs. Existing experimental approaches to measure TW function in tetrapods and bush-crickets are inherently invasive, compromising the fine-scale mechanics of each system. Located in the forelegs, the bush-cricket ear exhibits outer, middle and inner components; the inner ear containing tonotopically arranged auditory sensilla within a fluid-filled cavity, and externally protected by the leg cuticle. Here, we report bush-crickets with transparent ear cuticles as potential model species for direct, non-invasive measuring of TWs and tonotopy. Using laser Doppler vibrometry and spectroscopy, we show that increased transmittance of light through the ear cuticle allows for effective non-invasive measurements of TWs and frequency mapping. More transparent cuticles allow several properties of TWs to be precisely recovered and measured in vivo from intact specimens. Our approach provides an innovative, non-invasive alternative to measure the natural motion of the sensilla-bearing surface embedded in the intact inner ear fluid. PMID:28573026

Genome-wide scan reveals LEMD3 and WIF1 on SSC5 as the candidates for porcine ear size.

PubMed

Zhang, Longchao; Liang, Jing; Luo, Weizhen; Liu, Xin; Yan, Hua; Zhao, Kebin; Shi, Huibi; Zhang, Yuebo; Wang, Ligang; Wang, Lixian

2014-01-01

The quantitative trait loci (QTL) for porcine ear size was previously reported to mainly focus on SSC5 and SSC7. Recently, a missense mutation, G32E, in PPARD in the QTL interval on SSC7 was identified as the causative mutation for ear size. However, on account of the large interval of QTL, the responsible gene on SSC5 has not been identified. In this study, an intercross population was constructed from the large-eared Minzhu, an indigenous Chinese pig breed, and the Western commercial Large White pig to examine the genetic basis of ear size diversity. A GWAS was performed to detect SNPs significantly associated with ear size. Thirty-five significant SNPs defined a 10.78-Mb (30.14-40.92 Mb) region on SSC5. Further, combining linkage disequilibrium and haplotype sharing analysis, a reduced region of 3.07-Mb was obtained. Finally, by using a selective sweep analysis, a critical region of about 450-kb interval containing two annotated genes LEMD3 and WIF1 was refined in this work. Functional analysis indicated that both represent biological candidates for porcine ear size, with potential application in breeding programs. The two genes could also be used as novel references for further study of the mechanism underlying human microtia.

Gross and fine dissection of inner ear sensory epithelia in adult zebrafish (Danio rerio).

PubMed

Liang, Jin; Burgess, Shawn M

2009-05-08

Neurosensory epithelia in the inner ear are the crucial structures for hearing and balance functions. Therefore, it is important to understand the cellular and molecular features of the epithelia, which are mainly composed of two types of cells: hair cells (HCs) and supporting cells (SCs). Here we choose to study the inner ear sensory epithelia in adult zebrafish not only because the epithelial structures are highly conserved in all vertebrates studied, but also because the adult zebrafish is able to regenerate HCs, an ability that mammals lose shortly after birth. We use the inner ear of adult zebrafish as a model system to study the mechanisms of inner ear HC regeneration in adult vertebrates that could be helpful for clinical therapy of hearing/balance deficits in human as a result of HC loss. Here we demonstrate how to do gross and fine dissections of inner ear sensory epithelia in adult zebrafish. The gross dissection removes the tissues surrounding the inner ear and is helpful for preparing tissue sections, which allows us to examine the detailed structure of the sensory epithelia. The fine dissection cleans up the non-sensory-epithelial tissues of each individual epithelium and enables us to examine the heterogeneity of the whole epithelium easily in whole-mount epithelial samples.

Cilia distribution and polarity in the epithelial lining of the mouse middle ear cavity

PubMed Central

Luo, Wenwei; Yi, Hong; Taylor, Jeannette; Li, Jian-dong; Chi, Fanglu; Todd, N. Wendell; Lin, Xi; Ren, Dongdong; Chen, Ping

2017-01-01

The middle ear conducts sound to the cochlea for hearing. Otitis media (OM) is the most common illness in childhood. Moreover, chronic OM with effusion (COME) is the leading cause of conductive hearing loss. Clinically, COME is highly associated with Primary Ciliary Dyskinesia, implicating significant contributions of cilia dysfunction to COME. The understanding of middle ear cilia properties that are critical to OM susceptibility, however, is limited. Here, we confirmed the presence of a ciliated region near the Eustachian tube orifice at the ventral region of the middle ear cavity, consisting mostly of a lumen layer of multi-ciliated and a layer of Keratin-5-positive basal cells. We also found that the motile cilia are polarized coordinately and display a planar cell polarity. Surprisingly, we also found a region of multi-ciliated cells that line the posterior dorsal pole of the middle ear cavity which was previously thought to contain only non-ciliated cells. Our study provided a more complete understanding of cilia distribution and revealed for the first time coordinated polarity of cilia in the epithelium of the mammalian middle ear, thus illustrating novel structural features that are likely critical for middle ear functions and related to OM susceptibility. PMID:28358397

Evolution of vertebrate mechanosensory hair cells and inner ears: toward identifying stimuli that select mutation driven altered morphologies

PubMed Central

Fritzsch, Bernd; Straka, Hans

2014-01-01

Among the major distance senses of vertebrates, the ear is unique in its complex morphological changes during evolution. Conceivably, these changes enable the ear to adapt toward sensing various physically well-characterized stimuli. This review develops a scenario that integrates sensory cell with organ evolution. We propose that molecular and cellular evolution of the vertebrate hair cells occurred prior to the formation of the vertebrate ear. We previously proposed that the genes driving hair cell differentiation, were aggregated in the otic region through developmental re-patterning that generated a unique vertebrate embryonic structure, the otic placode. In agreement with the presence of graviceptive receptors in many vertebrate outgroups, it is likely that the vertebrate ear originally functioned as a simple gravity-sensing organ. Based on the rare occurrence of angular acceleration receptors in vertebrate outgroups, we further propose that the canal system evolved with a more sophisticated ear morphogenesis. This evolving morphogenesis obviously turned the initial otocyst into a complex set of canals and recesses, harboring multiple sensory epithelia each adapted to the acquisition of a specific aspect of a given physical stimulus. As support for this evolutionary progression, we provide several details of the molecular basis of ear development. PMID:24281353

Gene therapy restores auditory and vestibular function in a mouse model of Usher syndrome type 1c.

PubMed

Pan, Bifeng; Askew, Charles; Galvin, Alice; Heman-Ackah, Selena; Asai, Yukako; Indzhykulian, Artur A; Jodelka, Francine M; Hastings, Michelle L; Lentz, Jennifer J; Vandenberghe, Luk H; Holt, Jeffrey R; Géléoc, Gwenaëlle S

2017-03-01

Because there are currently no biological treatments for hearing loss, we sought to advance gene therapy approaches to treat genetic deafness. We focused on Usher syndrome, a devastating genetic disorder that causes blindness, balance disorders and profound deafness, and studied a knock-in mouse model, Ush1c c.216G>A, for Usher syndrome type IC (USH1C). As restoration of complex auditory and balance function is likely to require gene delivery systems that target auditory and vestibular sensory cells with high efficiency, we delivered wild-type Ush1c into the inner ear of Ush1c c.216G>A mice using a synthetic adeno-associated viral vector, Anc80L65, shown to transduce 80-90% of sensory hair cells. We demonstrate recovery of gene and protein expression, restoration of sensory cell function, rescue of complex auditory function and recovery of hearing and balance behavior to near wild-type levels. The data represent unprecedented recovery of inner ear function and suggest that biological therapies to treat deafness may be suitable for translation to humans with genetic inner ear disorders.

Optical measurement of the weak non-linearity in the eardrum vibration response to auditory stimuli

NASA Astrophysics Data System (ADS)

Aerts, Johan

The mammalian hearing organ consists of the external ear (auricle and ear canal) followed by the middle ear (eardrum and ossicles) and the inner ear (cochlea). Its function is to convert the incoming sound waves and convert them into nerve pulses which are processed in the final stage by the brain. The main task of the external and middle ear is to concentrate the incoming sound waves on a smaller surface to reduce the loss that would normally occur in transmission from air to inner ear fluid. In the past it has been shown that this is a linear process, thus without serious distortions, for sound waves going up to pressures of 130 dB SPL (˜90 Pa). However, at large pressure changes up to several kPa, the middle ear movement clearly shows non-linear behaviour. Thus, it is possible that some small non-linear distortions are also present in the middle ear vibration at lower sound pressures. In this thesis a sensitive measurement set-up is presented to detect this weak non-linear behaviour. Essentially, this set-up consists of a loud-speaker which excites the middle ear, and the resulting vibration is measured with an heterodyne vibrometer. The use of specially designed acoustic excitation signals (odd random phase multisines) enables the separation of the linear and non-linear response. The application of this technique on the middle ear demonstrates that there are already non-linear distortions present in the vibration of the middle ear at a sound pressure of 93 dB SPL. This non-linear component also grows strongly with increasing sound pressure. Knowledge of this non-linear component can contribute to the improvement of modern hearing aids, which operate at higher sound pressures where the non-linearities could distort the signal considerably. It is also important to know the contribution of middle ear non-linearity to otoacoustic emissions. This are non-linearities caused by the active feedback amplifier in the inner ear, and can be detected in the external and middle ear. These signals are used for diagnostic purposes, and therefore it is important to have an estimate the non-linear middle ear contribution to these emissions.

In Vivo Analysis of Lrig Genes Reveals Redundant and Independent Functions in the Inner Ear

PubMed Central

del Rio, Tony; Nishitani, Allison M.; Yu, Wei-Ming; Goodrich, Lisa V.

2013-01-01

Lrig proteins are conserved transmembrane proteins that modulate a variety of signaling pathways from worm to humans. In mammals, there are three family members – Lrig1, Lrig2, and Lrig3 – that are defined by closely related extracellular domains with a similar arrangement of leucine rich repeats and immunoglobulin domains. However, the intracellular domains show little homology. Lrig1 inhibits EGF signaling through internalization and degradation of ErbB receptors. Although Lrig3 can also bind ErbB receptors in vitro, it is unclear whether Lrig2 and Lrig3 exhibit similar functions to Lrig1. To gain insights into Lrig gene functions in vivo, we compared the expression and function of the Lrigs in the inner ear, which offers a sensitive system for detecting effects on morphogenesis and function. We find that all three family members are expressed in the inner ear throughout development, with Lrig1 and Lrig3 restricted to subsets of cells and Lrig2 expressed more broadly. Lrig1 and Lrig3 overlap prominently in the developing vestibular apparatus and simultaneous removal of both genes disrupts inner ear morphogenesis. This suggests that these two family members act redundantly in the otic epithelium. In contrast, although Lrig1 and Lrig2 are frequently co-expressed, Lrig1−/−;Lrig2−/− double mutant ears show no enhanced structural abnormalities. At later stages, Lrig1 expression is sustained in non-sensory tissues, whereas Lrig2 levels are enhanced in neurons and sensory epithelia. Consistent with these distinct expression patterns, Lrig1 and Lrig2 mutant mice exhibit different forms of impaired auditory responsiveness. Notably, Lrig1−/−;Lrig2−/− double mutant mice display vestibular deficits and suffer from a more severe auditory defect that is accompanied by a cochlear innervation phenotype not present in single mutants. Thus, Lrig genes appear to act both redundantly and independently, with Lrig2 emerging as the most functionally distinct family member. PMID:24086156

Localization of soluble guanylate cyclase activity in the guinea pig inner ear.

PubMed

Takumida, M; Anniko, M; Popa, R; Zhang, D M

2000-01-01

The aim of this study was to characterize the nitric oxide (NO) receptor soluble guanylate cyclase (sGC), to determine the cells targeted by NO and to elucidate the function of the NO/cGMP pathway in the inner ear. sGC activity in the inner ear was localized by immunohistochemical detection of NO-stimulated cGMP. Soluble guanylate cyclase activity in the cochlea was detected in the nerve endings underneath the outer and inner hair cells, supporting cells, stria vascularis and vessels. In the vestibular organs, sGC activity was detected in the cytoplasm of sensory cells, nerve fibres, dark cells and transitional cells and vessels. These findings suggest that the NO/cGMP pathway may be involved in regulatory processes in neurotransmission, blood flow and inner ear fluid homeostasis.

Words matter: Implementing the electronically activated recorder in schizotypy.

PubMed

Minor, Kyle S; Davis, Beshaun J; Marggraf, Matthew P; Luther, Lauren; Robbins, Megan L

2018-03-01

In schizophrenia-spectrum populations, analyzing the words people use has offered promise for unlocking information about affective states and social behaviors. The electronically activated recorder (EAR) is an application-based program that is combined with widely used smartphone technology to capture a person's real-world interactions via audio recordings. It improves on the ecological validity of current methodologies by providing objective and naturalistic samples of behavior. This study is the first to implement the EAR in people endorsing elevated traits of schizophrenia-spectrum personality disorders (i.e., schizotypy), and we expected the EAR to (a) differentiate high and low schizotypy groups on affective disturbances and social engagement and (b) show that high schizotypy status moderates links between affect and social behavior using a multimethod approach. Lexical analysis of EAR recordings revealed greater negative affect and decreased social engagement in those high in schizotypy. When assessing specific traits, EAR and ecological momentary assessment (EMA) converged to show that positive schizotypy predicted negative affect. Finally, high schizotypy status moderated links between negative affect and social engagement when the EAR was combined with EMA. Adherence did not influence results, as both groups wore the EAR more than 90% of their waking hours. Findings supported using the EAR to assess real-world expressions of personality and functioning in schizotypy. Evidence also showed that the EAR can be used alongside EMA to provide a mixed-method, real-world assessment that is high in ecological validity and offers a window into the daily lives of those with elevated traits of schizophrenia-spectrum personality disorders. (PsycINFO Database Record (c) 2018 APA, all rights reserved).

Asymmetry of temporal auditory T-complex: right ear-left hemisphere advantage in Tb timing in children.

PubMed

Bruneau, Nicole; Bidet-Caulet, Aurélie; Roux, Sylvie; Bonnet-Brilhault, Frédérique; Gomot, Marie

2015-02-01

To investigate brain asymmetry of the temporal auditory evoked potentials (T-complex) in response to monaural stimulation in children compared to adults. Ten children (7 to 9 years) and ten young adults participated in the study. All were right-handed. The auditory stimuli used were tones (1100 Hz, 70 dB SPL, 50 ms duration) delivered monaurally (right, left ear) at four different levels of stimulus onset asynchrony (700-1100-1500-3000 ms). Latency and amplitude of responses were measured at left and right temporal sites according to the ear stimulated. Peaks of the three successive deflections (Na-Ta-Tb) of the T-complex were greater in amplitude and better defined in children than in adults. Amplitude measurements in children indicated that Na culminates on the left hemisphere whatever the ear stimulated whereas Ta and Tb culminate on the right hemisphere but for left ear stimuli only. Peak latency displayed different patterns of asymmetry. Na and Ta displayed shorter latencies for contralateral stimulation. The original finding was that Tb peak latency was the shortest at the left temporal site for right ear stimulation in children. Amplitude increased and/or peak latency decreased with increasing SOA, however no interaction effect was found with recording site or with ear stimulated. Our main original result indicates a right ear-left hemisphere timing advantage for Tb peak in children. The Tb peak would therefore be a good candidate as an electrophysiological marker of ear advantage effects during dichotic stimulation and of functional inter-hemisphere interactions and connectivity in children. Copyright © 2014. Published by Elsevier B.V.

Preventing hearing damage using topical dexamethasone during reversible cochlear ischemia: an animal model.

PubMed

Morawski, Krzysztof; Telischi, Fred F; Bohorquez, Jorge; Niemczyk, Kazimierz

2009-09-01

Local application of dexamethasone to the round window (RW) niche prevents cochlear damage caused by local reversible ischemia. Cochlear ischemia induced by internal auditory artery (IAA) compression/stretching is thought to cause postoperative sensory hearing loss after attempted hearing preservation removal of acoustic neuroma tumors. Dexamethasone administered to the RW niche traveling through the membrane to the cochlear fluids may prevent ischemic damage. Ten young albino rabbits were used for this study. Ischemic episodes were induced by compressing the IAA. Laser Doppler cochlear blood flow was measured using a probe positioned at the RW niche. Transtympanic electrocochleography was measured at 4, 8, and 12 kHz. In 5 test ears, dexamethasone was administered topically at the RW for approximately 50 minutes before the IAA compressions, whereas in 5 control ears, saline was applied in the same way. Each ear underwent one 10-minute IAA compression with a 60-minute postischemic period of transtympanic electrocochleography monitoring. In both control- and dexamethasone-treated ears, ischemic episodes measured by Laser Doppler cochlear blood flow were comparable. Fifty minutes after IAA decompression, in dexamethasone-pretreated ears, cochlear microphonic and compound action potential amplitudes at all test frequencies were 10 to 15% less reduced than those in control ears. Compound action potential latencies in dexamethasone-pretreated ears resulted in shorter latency delay than in control ears. The RW seems to be an efficacious route for the administration of dexamethasone into the inner ear. Dexamethasone showed a protective effect on cochlear function after local ischemia. Transtympanic electrocochleography was found to be a sufficient and effective tool in monitoring hearing.

Paddy-field contamination with 134Cs and 137Cs due to Fukushima Dai-ichi Nuclear Power Plant accident and soil-to-rice transfer coefficients.

PubMed

Endo, Satoru; Kajimoto, Tsuyoshi; Shizuma, Kiyoshi

2013-02-01

The transfer coefficient (TF) from soil to rice plants of (134)Cs and (137)Cs in the form of radioactive deposition from the Fukushima Dai-ichi Nuclear Power Plant (FDNPP) accident in March 2011 was investigated in three rice paddy fields in Minami-Soma City. Rice crops were planted in the following May and harvested at the end of September. Soil cores of 30-cm depth were sampled from rice-planted paddy fields to measure (134)Cs and (137)Cs radioactivity at 5-cm intervals. (134)Cs and (137)Cs radioactivity was also measured in rice ears (rice with chaff), straws and roots. The rice ears were subdivided into chaff, brown rice, polished rice and rice bran, and the (134)Cs and (137)Cs radioactivity concentration of each plant part was measured to calculate the respective TF from the soil. The TF of roots was highest at 0.48 ± 0.10 in the field where the (40)K concentration in the soil core was relatively low, in comparison with TF values of 0.31 and 0.38 in other fields. Similar trends could be found for the TF of whole rice plants, excluding roots. The TF of rice ears was relatively low at 0.019-0.026. The TF of chaff, rice bran, brown rice and polished rice was estimated to be 0.049, 0.10-0.16, 0.013-0.017 and 0.005-0.013, respectively. Copyright © 2012 Elsevier Ltd. All rights reserved.

Use of the 'real-ear to dial difference' to derive real-ear SPL from hearing level obtained with insert earphones.

PubMed

Munro, K J; Lazenby, A

2001-10-01

The electroacoustic characteristics of a hearing instrument are normally selected for individuals using data obtained during audiological assessment. The precise inter-relationship between the electroacoustic and audiometric variables is most readily appreciated when they have been measured at the same reference point, such as the tympanic membrane. However, it is not always possible to obtain the real-ear sound pressure level (SPL) directly if this is below the noise floor of the probe-tube microphone system or if the subject is unco-operative. The real-ear SPL may be derived by adding the subject's real-ear to dial difference (REDD) acoustic transform to the audiometer dial setting. The aim of the present study was to confirm the validity of the Audioscan RM500 to measure the REDD with the ER-3A insert earphone. A probe-tube microphone was used to measure the real-ear SPL and REDD from the right ears of 16 adult subjects ranging in age from 22 to 41 years (mean age 27 years). Measurements were made from 0.25 kHz to 6 kHz at a dial setting of 70 dB with an ER-3A insert earphone and two earmould configurations: the EAR-LINK foam ear-tip and the subjects' customized skeleton earmoulds. Mean REDD varied as a function of frequency but was typically approximately 12 dB with a standard deviation (SD) of +/- 1.7 dB and +/- 2.7 dB for the foam ear-tip and customized earmould, respectively. The mean test-retest difference of the REDD varied with frequency but was typically 0.5 dB (SD 1 dB). Over the frequency range 0.5-4 kHz, the derived values were found to be within 5 dB of the measured values in 95% of subjects when using the EAR-LINK foam ear-tip and within 4 dB when using the skeleton earmould. The individually measured REDD transform can be used in clinical practice to derive a valid estimate of real-ear SPL when it has not been possible to measure this directly.

Role of neutralizing antibodies and T-cells in pathogenesis of herpes simplex virus infection in congenitally athymic mice.

PubMed

Kapoor, A K; Buckmaster, A; Nash, A A; Field, H J; Wildy, P

1982-11-01

Congenitally athymic nude mice were infected with 10(4) p.f.u. herpes simplex type 1 (strain SC16). Following the passive transfer of neutralizing monoclonal antibodies (AP7, AP8 and AP12) it was observed that AP7 alone reduced the virus infectivity in the nervous system; AP8 and AP12 failed to protect mice probably due to poor in vivo binding to the neutralization site on the virus. Latent ganglionic infection could be established in nude mice following adoptive transfer of optimum number (2 x 10(7) cells/mouse) of immune lymph node cells from day 7 herpes virus-infected hairy immunocompetent donor mice. Moreover, in some of the immune lymph node cell protected nudes, latency could be maintained even in complete absence of neutralizing antibodies. Results of ear-ablation experiments revealed that removal of primary source of infection after day 5 of infection reduced the amount of virus in the ganglia and spinal cord. Acute neurological infection was not detected following transfer of protective anti-gp-D neutralizing antibody (LP2) in combination with removal of infected pinna. These data suggest that continuous seeding of virus occurs in related ganglia via the axonal route from infected ear pinna. It appears that local T-cell-mediated immune mechanisms are involved in maintenance of latency.

76 FR 37634 - Revision to the Validated End-User Authorization for CSMC Technologies Corporation in the People...

Federal Register 2010, 2011, 2012, 2013, 2014

2011-06-28

...: Karen Nies-Vogel, Chair, End-User Review Committee, Office of the Assistant Secretary, Export... amended the EAR in a final rule on June 19, 2007 (72 FR 33646), creating a new authorization for..., reexported, or transferred (in-country) under a general authorization instead of a license, in conformance...

Rhesus Cochlear and Vestibular Functions Are Preserved After Inner Ear Injection of Saline Volume Sufficient for Gene Therapy Delivery.

PubMed

Dai, Chenkai; Lehar, Mohamed; Sun, Daniel Q; Rvt, Lani Swarthout; Carey, John P; MacLachlan, Tim; Brough, Doug; Staecker, Hinrich; Della Santina, Alexandra M; Hullar, Timothy E; Della Santina, Charles C

2017-08-01

Sensorineural losses of hearing and vestibular sensation due to hair cell dysfunction are among the most common disabilities. Recent preclinical research demonstrates that treatment of the inner ear with a variety of compounds, including gene therapy agents, may elicit regeneration and/or repair of hair cells in animals exposed to ototoxic medications or other insults to the inner ear. Delivery of gene therapy may also offer a means for treatment of hereditary hearing loss. However, injection of a fluid volume sufficient to deliver an adequate dose of a pharmacologic agent could, in theory, cause inner ear trauma that compromises functional outcome. The primary goal of the present study was to assess that risk in rhesus monkeys, which closely approximates humans with regard to middle and inner ear anatomy. Secondary goals were to identify the best delivery route into the primate ear from among two common surgical approaches (i.e., via an oval window stapedotomy and via the round window) and to determine the relative volumes of rhesus, rodent, and human labyrinths for extrapolation of results to other species. We measured hearing and vestibular functions before and 2, 4, and 8 weeks after unilateral injection of phosphate-buffered saline vehicle (PBSV) into the perilymphatic space of normal rhesus monkeys at volumes sufficient to deliver an atoh1 gene therapy vector. To isolate effects of injection, PBSV without vector was used. Assays included behavioral observation, auditory brainstem responses, distortion product otoacoustic emissions, and scleral coil measurement of vestibulo-ocular reflexes during whole-body rotation in darkness. Three groups (N = 3 each) were studied. Group A received a 10 μL transmastoid/trans-stapes injection via a laser stapedotomy. Group B received a 10 μL transmastoid/trans-round window injection. Group C received a 30 μL transmastoid/trans-round window injection. We also measured inner ear fluid space volume via 3D reconstruction of computed tomography (CT) images of adult C57BL6 mouse, rat, rhesus macaque, and human temporal bones (N = 3 each). Injection was well tolerated by all animals, with eight of nine exhibiting no signs of disequilibrium and one animal exhibiting transient disequilibrium that resolved spontaneously by 24 h after surgery. Physiologic results at the final, 8-week post-injection measurement showed that injection was well tolerated. Compared to its pretreatment values, no treated ear's ABR threshold had worsened by more than 5 dB at any stimulus frequency; distortion product otoacoustic emissions remained detectable above the noise floor for every treated ear (mean, SD and maximum deviation from baseline: -1.3, 9.0, and -18 dB, respectively); and no animal exhibited a reduction of more than 3 % in vestibulo-ocular reflex gain during high-acceleration, whole-body, passive yaw rotations in darkness toward the treated side. All control ears and all operated ears with definite histologic evidence of injection through the intended site showed similar findings, with intact hair cells in all five inner ear sensory epithelia and intact auditory/vestibular neurons. The relative volumes of mouse, rat, rhesus, and human inner ears as measured by CT were (mean ± SD) 2.5 ± 0.1, 5.5 ± 0.4, 59.4 ± 4.7 and 191.1 ± 4.7 μL. These results indicate that injection of PBSV at volumes sufficient for gene therapy delivery can be accomplished without destruction of inner ear structures required for hearing and vestibular sensation.

Functional Ear (A)Symmetry in Brainstem Neural Activity Relevant to Encoding of Voice Pitch: A Precursor for Hemispheric Specialization?

ERIC Educational Resources Information Center

Krishnan, Ananthanarayan; Gandour, Jackson T.; Ananthakrishnan, Saradha; Bidelman, Gavin M.; Smalt, Christopher J.

2011-01-01

Pitch processing is lateralized to the right hemisphere; linguistic pitch is further mediated by left cortical areas. This experiment investigates whether ear asymmetries vary in brainstem representation of pitch depending on linguistic status. Brainstem frequency-following responses (FFRs) were elicited by monaural stimulation of the left and…

Functionality of a maize chitinase potentially involved in ear rot pathogen resistance

USDA-ARS?s Scientific Manuscript database

Chitinases are thought to play a role in plant resistance to fungal pathogens by degrading the fungal cell wall, but few have been investigated to any great extent. The gene for a maize (Zea mays) chitinase “chitinase 2” previously reported to be induced by two ear rot pathogens in infected tissues ...

Northern long-eared bat day-roosting and prescribed fire in the central Appalachians, USA

Treesearch

W. Mark Ford; Alexander Silvis; Joshua B. Johnson; John W. Edwards; Milu Karp

2016-01-01

The northern long-eared bat (Myotis septentrionalis Trovessart) is a cavity-roosting species that forages in cluttered upland and riparian forests throughout the oak-dominated Appalachian and Central Hardwoods regions. Common prior to white-nose syndrome, the population of this bat species has declined to functional extirpation in some regions in...

Bug-in-Ear Coaching: Impacts on Early Childhood Educators' Practices and Associations with Toddlers' Expressive Communication

ERIC Educational Resources Information Center

Ottley, Jennifer Riggie; Hanline, Mary Frances

2014-01-01

Many early childhood educators struggle to meet the communication needs of children with delays and disabilities. The purpose of this study was to examine the functional relation between bug-in-ear coaching and the frequency of educators' correct use of targeted communication strategies, as well as associations with children's expressive…

Shape and 3D acoustically induced vibrations of the human eardrum characterized by digital holography

NASA Astrophysics Data System (ADS)

Khaleghi, Morteza; Furlong, Cosme; Cheng, Jeffrey Tao; Rosowski, John J.

2014-07-01

The eardrum or Tympanic Membrane (TM) transfers acoustic energy from the ear canal (at the external ear) into mechanical motions of the ossicles (at the middle ear). The acousto-mechanical-transformer behavior of the TM is determined by its shape and mechanical properties. For a better understanding of hearing mysteries, full-field-of-view techniques are required to quantify shape, nanometer-scale sound-induced displacement, and mechanical properties of the TM in 3D. In this paper, full-field-of-view, three-dimensional shape and sound-induced displacement of the surface of the TM are obtained by the methods of multiple wavelengths and multiple sensitivity vectors with lensless digital holography. Using our developed digital holographic systems, unique 3D information such as, shape (with micrometer resolution), 3D acoustically-induced displacement (with nanometer resolution), full strain tensor (with nano-strain resolution), 3D phase of motion, and 3D directional cosines of the displacement vectors can be obtained in full-field-ofview with a spatial resolution of about 3 million points on the surface of the TM and a temporal resolution of 15 Hz.

An overview of changes in pressure values of the middle ear using impedance audiometry among diver candidates in a hyperbaric chamber before and after a pressure test

NASA Astrophysics Data System (ADS)

Anoraga, J. S.; Bramantyo, B.; Bardosono, S.; Simanungkalit, S. H.; Basiruddin, J.

2017-08-01

Impedance audiometry is not yet routinely used in pressure tests, especially in Indonesia. Direct exposure to pressure in a hyperbaric chamber is sometimes without any assessment of the middle ear or the Eustachian tube function (ETF) of ventilation. Impedance audiometry examinations are important to assess ETF ventilation. This study determined the middle ear pressure value changes associated with the ETF (ventilation) of prospective divers. This study included 29 prospective divers aged 20-40 years without conductive hearing loss. All subjects underwent a modified diving impedance audiometry examination both before and after the pressure test in a double-lock hyperbaric chamber. Using the Toynbee maneuver, the values obtained for changes of pressure in the middle ear were significant before and after the pressure test in the right and left ears: p < 0.001 and p = 0.018, respectively. The impedance audiometry examination is necessary for the selection of candidate divers undergoing pressure tests within a hyperbaric chamber.

Zebrafish models of human eye and inner ear diseases.

PubMed

Blanco-Sánchez, B; Clément, A; Phillips, J B; Westerfield, M

2017-01-01

Eye and inner ear diseases are the most common sensory impairments that greatly impact quality of life. Zebrafish have been intensively employed to understand the fundamental mechanisms underlying eye and inner ear development. The zebrafish visual and vestibulo-acoustic systems are very similar to these in humans, and although not yet mature, they are functional by 5days post-fertilization (dpf). In this chapter, we show how the zebrafish has significantly contributed to the field of biomedical research and how researchers, by establishing disease models and meticulously characterizing their phenotypes, have taken the first steps toward therapies. We review here models for (1) eye diseases, (2) ear diseases, and (3) syndromes affecting eye and/or ear. The use of new genome editing technologies and high-throughput screening systems should increase considerably the speed at which knowledge from zebrafish disease models is acquired, opening avenues for better diagnostics, treatments, and therapies. Copyright © 2017 Elsevier Inc. All rights reserved.

Interspecies nuclear transfer using fibroblasts from leopard, tiger, and lion ear piece collected postmortem as donor cells and rabbit oocytes as recipients.

PubMed

Yelisetti, Uma Mahesh; Komjeti, Suman; Katari, Venu Charan; Sisinthy, Shivaji; Brahmasani, Sambasiva Rao

2016-06-01

Skin fibroblast cells were obtained from a small piece of an ear of leopard, lion, and tiger collected postmortem and attempts were made to synchronize the skin fibroblasts at G0/G1 of cell cycle using three different approaches. Efficiency of the approaches was tested following interspecies nuclear transfer with rabbit oocytes as recipient cytoplasm. Fluorescence-activated cell sorting revealed that the proportion of G0/G1 cells increased significantly (P < 0.05) when cells subjected to serum starvation, contact inhibition, and 3 mM sodium butyrate (NaBu) treatment when compared with cycling cells. However, 3 mM NaBu treatment caused alterations in cell morphology and increase in dead cells. Thus, interspecies nuclear transfer was carried out using fibroblast cells subjected to contact inhibition for 72 h, serum starvation for 48 h, and cells treated with 1.0 mM NaBu for 48 h. The fusion rates, the proportion of fused couplets that cleaved to two-cell and developed to blastocyst, were highest in all three species when the donor cells were treated with 1.0 mM NaBu for 48 h. But, the blastocyst percentage of interspecies nuclear embryos (5-6%) was significantly lower when compared with rabbit-rabbit nuclear transfer embryos (22.9%). In conclusion, fibroblast cells of leopard, lion, and tiger were successfully synchronized and used for the development of blastocysts using rabbit oocytes as recipient cytoplasm.

The effect of continuous positive airway pressure on middle ear pressure.

PubMed

Lin, Fred Y; Gurgel, Richard K; Popelka, Gerald R; Capasso, Robson

2012-03-01

While continuous positive airway pressure (CPAP) is commonly used for obstructive sleep apnea treatment, its effect on middle ear pressure is unknown. The purpose of this study was to measure the effect of CPAP on middle ear pressure and describe the correlation between CPAP levels and middle ear pressures. Retrospective review of normal tympanometry values and a prospective cohort evaluation of subjects' tympanometric values while using CPAP at distinct pressure levels. A total of 3,066 tympanograms were evaluated to determine the normal range of middle ear pressures. Ten subjects with no known history of eustachian tube dysfunction or obstructive sleep apnea had standard tympanometry measurements while wearing a CPAP device. Measurements were taken at baseline and with CPAP air pressures of 0, 5, 10, and 15 cm H(2)O. The percentage of normal control patients with middle ear pressures above 40 daPa was 0.03%. In the study population, prior to a swallowing maneuver to open the eustachian tube, average middle ear pressures were 21.67 daPa, 22.63 daPa, 20.42, daPa, and 21.58 daPa with CPAP pressures of 0, 5, 10, and 15 cm H(2) 0, respectively. After swallowing, average middle ear air pressures were 18.83 daPa, 46.75 daPa, 82.17 daPa, and 129.17 daPa with CPAP pressures of 0, 5, 10, and 15 cm H(2)0, respectively. The postswallow Pearson correlation coefficient correlating CPAP and middle ear pressures was 0.783 (P < 0.001). Middle ear air pressure is directly proportional to CPAP air pressure in subjects with normal eustachian tube function. Middle ear pressure reaches supraphysiologic levels at even minimal CPAP levels. Although further investigation is necessary, there may be otologic implications for patients who are chronically CPAP dependent. These findings may also influence the perioperative practice of otologic and skull base surgeons. Copyright © 2011 The American Laryngological, Rhinological, and Otological Society, Inc.

Temporal and spatial expression patterns of Hedgehog receptors in the developing inner and middle ear.

PubMed

Shin, Jeong-Oh; Ankamreddy, Harinarayana; Jakka, Naga Mahesh; Lee, Seokwon; Kim, Un-Kyung; Bok, Jinwoong

2017-01-01

The mammalian inner ear is a complex organ responsible for balance and hearing. Sonic hedgehog (Shh), a member of the Hedgehog (Hh) family of secreted proteins, has been shown to play important roles in several aspects of inner ear development, including dorsoventral axial specification, cochlear elongation, tonotopic patterning, and hair cell differentiation. Hh proteins initiate a downstream signaling cascade by binding to the Patched 1 (Ptch1) receptor. Recent studies have revealed that other types of co-receptors can also mediate Hh signaling, including growth arrest-specific 1 (Gas1), cell-adhesion molecules-related/down-regulated by oncogenes (Cdon), and biregional Cdon binding protein (Boc). However, little is known about the role of these Hh co-receptors in inner ear development. In this study, we examined the expression patterns of Gas1, Cdon, and Boc, as well as that of Ptch1, in the developing mouse inner ear from otocyst (embryonic day (E) 9.5) until birth and in the developing middle ear at E15.5. Ptch1, a readout of Hh signaling, was expressed in a graded pattern in response to Shh signaling throughout development. Expression patterns of Gas1, Cdon, and Boc differed from that of Ptch1, and each Hh co-receptor was expressed in specific cells and domains in the developing inner and middle ear. These unique and differential expression patterns of Hh co-receptors suggest their roles in mediating various time- and space-specific functions of Shh during ear development.

Analysis of subtle auditory dysfunctions in young normal-hearing subjects affected by Williams syndrome.

PubMed

Paglialonga, Alessia; Barozzi, Stefania; Brambilla, Daniele; Soi, Daniela; Cesarani, Antonio; Spreafico, Emanuela; Tognola, Gabriella

2014-11-01

To assess if young subjects affected by Williams syndrome (WS) with normal middle ear functionality and normal hearing thresholds might have subtle auditory dysfunctions that could be detected by using clinically available measurements. Otoscopy, acoustic reflexes, tympanometry, pure-tone audiometry, and distortion product otoacoustic emissions (DPOAEs) were measured in a group of 13 WS subjects and in 13 age-matched, typically developing control subjects. Participants were required to have normal otoscopy, A-type tympanogram, normal acoustic reflex thresholds, and pure-tone thresholds≤15 dB HL at 0.5, 1, and 2 kHz bilaterally. To limit the possible influence of middle ear status on DPOAE recordings, we analyzed only data from ears with pure-tone thresholds≤15 dB HL across all octave frequencies in the range 0.25-8 kHz, middle ear pressure (MEP)>-50 daPa, static compliance (SC) in the range 0.3-1.2 cm3, and ear canal volume (ECV) in the range 0.2-2 ml, and we performed analysis of covariance to remove the possible effects of middle ear variables on DPOAEs. No differences in mean hearing thresholds, SC, ECV, and gradient were observed between the two groups, whereas significantly lower MEP values were found in WS subjects as well as significantly decreased DPOAEs up to 3.2 kHz after adjusting for differences in middle ear status. Results revealed that WS subjects with normal hearing thresholds (≤15 dB HL) and normal middle ear functionality (MEP>-50 daPa, SC in the range 0.3-1.2 cm3, ECV in the range 0.2-2 ml) might have subtle auditory dysfunctions that can be detected by using clinically available methods. Overall, this study points out the importance of using otoacoustic emissions as a complement to routine audiological examinations in individuals with WS to detect, before the onset of hearing loss, possible subtle auditory dysfunctions so that patients can be early identified, better monitored, and promptly treated. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.

Malleus-to-footplate prosthetic interposition: experience with 265 patients.

PubMed

Colletti, V; Fiorino, F G

1999-03-01

Absence of the long process of the incus with or without absence of the stapes head accounts for more than 80% of ossicular discontinuities. Total or partial replacement prostheses, made of various materials, are interposed to restore the transfer function of the middle ear. To simplify ossicular reconstruction, reduce operative times and costs, improve functional outcomes, and avoid the risk of infections, we have adopted, during the past 10 years, a technique that makes use of a personally designed alloplastic prosthetic device. The prosthesis connects the malleus to the footplate, even in the presence of the stapes superstructure. This malleus-to-footplate prosthesis consists in a plastipore-coated steel piston and hydroxyapatite head, complete with a groove. The groove is placed beneath the malleus neck after dissection of the tensor tympani tendon and the shaft of the piston on the footplate. Two hundred ninety primary ossiculoplasties with the malleus-to-footplate prostheses were performed in 265 patients from 1986 to 1995 in the ENT Department of the University of Verona. The average postoperative air-bone gap at 0.5 to 3 kHz was 11 dB at 1 year and 14 dB at 5 years. These outcomes are significantly better than those personally obtained previously with ossicular or alloplastic prostheses. No extrusions occurred. The structural characteristics of the malleus-to-foot-plate prosthesis endow the prosthesis with a high degree of biocompatibility and stability and optimal sound-transfer function. The rationale for this particular ossiculoplasty procedure is discussed.

Comparative acoustic performance and mechanical properties of silk membranes for the repair of chronic tympanic membrane perforations.

PubMed

Allardyce, Benjamin J; Rajkhowa, Rangam; Dilley, Rodney J; Xie, Zhigang; Campbell, Luke; Keating, Adrian; Atlas, Marcus D; von Unge, Magnus; Wang, Xungai

2016-12-01

The acoustic and mechanical properties of silk membranes of different thicknesses were tested to determine their suitability as a repair material for tympanic membrane perforations. Membranes of different thickness (10-100μm) were tested to determine their frequency response and their resistance to pressure loads in a simulated ear canal model. Their mechanical rigidity to pressure loads was confirmed by tensile testing. These membranes were tested alongside animal cartilage, currently the strongest available myringoplasty graft as well as paper, which is commonly used for simpler procedures. Silk membranes showed resonant frequencies within the human hearing range and a higher vibrational amplitude than cartilage, suggesting that silk may offer good acoustic energy transfer characteristics. Silk membranes were also highly resistant to simulated pressure changes in the middle ear, suggesting they can resist retraction, a common cause of graft failure resulting from chronic negative pressures in the middle ear. Part of this strength can be explained by the substantially higher modulus of silk films compared with cartilage. This allows for the production of films that are much thinner than cartilage, with superior acoustic properties, but that still provide the same level of mechanical support as thicker cartilage. Together, these in vitro results suggest that silk membranes may provide good hearing outcomes while offering similar levels of mechanical support to the reconstructed middle ear. Copyright © 2016 Elsevier Ltd. All rights reserved.

Isolating the auditory system from acoustic noise during functional magnetic resonance imaging: Examination of noise conduction through the ear canal, head, and bodya)

PubMed Central

Ravicz, Michael E.; Melcher, Jennifer R.

2007-01-01

Approaches were examined for reducing acoustic noise levels heard by subjects during functional magnetic resonance imaging (fMRI), a technique for localizing brain activation in humans. Specifically, it was examined whether a device for isolating the head and ear canal from sound (a “helmet”) could add to the isolation provided by conventional hearing protection devices (i.e., earmuffs and earplugs). Both subjective attenuation (the difference in hearing threshold with versus without isolation devices in place) and objective attenuation (difference in ear-canal sound pressure) were measured. In the frequency range of the most intense fMRI noise (1–1.4 kHz), a helmet, earmuffs, and earplugs used together attenuated perceived sound by 55–63 dB, whereas the attenuation provided by the conventional devices alone was substantially less: 30–37 dB for earmuffs, 25–28 dB for earplugs, and 39–41 dB for earmuffs and earplugs used together. The data enabled the clarification of the relative importance of ear canal, head, and body conduction routes to the cochlea under different conditions: At low frequencies (≤500 Hz), the ear canal was the dominant route of sound conduction to the cochlea for all of the device combinations considered. At higher frequencies (>500 Hz), the ear canal was the dominant route when either earmuffs or earplugs were worn. However, the dominant route of sound conduction was through the head when both earmuffs and earplugs were worn, through both ear canal and body when a helmet and earmuffs were worn, and through the body when a helmet, earmuffs, and earplugs were worn. It is estimated that a helmet, earmuffs, and earplugs together will reduce the most intense fMRI noise levels experienced by a subject to 60–65 dB SPL. Even greater reductions in noise should be achievable by isolating the body from the surrounding noise field. PMID:11206150

Goldfish and oscars have comparable responsiveness to dipole stimuli

NASA Astrophysics Data System (ADS)

Nauroth, Ines Eva; Mogdans, Joachim

2009-12-01

The relative roles of the fish lateral line and inner ear for the perception of hydrodynamic stimuli are poorly investigated. Here, we studied responsiveness to a 100 Hz vibrating sphere (dipole stimulus) of goldfish and oscars, two species that differ in peripheral lateral line morphology, inner ear morphology, mechanical linkage between inner ear and swim bladder, and inner ear sensitivity. We measured unconditioned dipole-evoked changes in breathing activity in still water and in the presence of a 5-cm s-1 background flow. In still water, individuals from both species responded to sound pressure levels (SPLs) between 92 and 109 dB SPL re 1 μPaRMS. Responsiveness was not affected by background flow or by temporary inactivation of the lateral line. The data suggest that fish with different lateral line and inner ear morphologies have similar sensitivities to vibrating sphere stimuli and can detect and respond to dipole sources equally well in still water and in moderate background flows. Moreover, behavioral responses were not dependent on a functional lateral line, suggesting that in this type of experiment, the inner ear is the dominant sense organ for the perception of hydrodynamic stimuli.

Eustachian Tube Opening Measured by Sonotubometry is Poorer in Adults with a History of Past Middle Ear Disease

PubMed Central

Teixeira, Miriam S.; Banks, Juliane; Swarts, J. Douglas; Alper, Cuneyt M.; Doyle, William J.

2014-01-01

Objective Test the hypothesis that active Eustachian tube opening efficiency as measured by sonotubometry is higher in adults with no extant middle-ear disease and no history of previous otitis media (Group-1) when compared to adults with no middle-ear disease but a positive history for otitis media (Group-2). Methods Eustachian tube function for 1 ear of 33 otherwise healthy adult subjects, 16 assigned to Group-1 and 17 to Group-2, was tested by sonotubometry using a standard protocol. For each test, the sound envelopes for 3 swallows were abstracted independently by 2 observers from the data stream and 7 descriptive parameters related to sound envelope “shape” were calculated. Interrelatedness among the values for the parameters was explored using correlation analysis. The contributions of swallow, observer and group to the variance in each parameter were evaluated for significance using a General Linear Model. Results The shape parameters reflecting envelope height, area and rise and fall rates were highly inter-correlated, but those reflecting envelope widths were not. There was no effect of “swallow” on any of the parameters; but there was a significant “observer” effect on all measures of envelope width, greater for observer-2, and a significant “group” effect for 5 of the 7 shape parameters, all greater in Group-1. Conclusions Quantifiable measures of the sound signal “shape” recorded by sonotubometry during swallowing were significantly different between the 2 groups of subjects. This is interpretable as evidencing a more efficient Eustachian tube opening-function in adults with healthy middle ears who do not have a previous history of otitis media when compared to similar adults with a history of prior otitis media. Inefficient Eustachian tube function as children may not be completely resolved by adulthood increasing adult otitis media risk when Eustachian tube function is down-graded by extant upper respiratory diseases that provoke nasopharyngeal inflammation. PMID:24491807

The Effect of Microphone Placement on Interaural Level Differences and Sound Localization Across the Horizontal Plane in Bilateral Cochlear Implant Users.

PubMed

Jones, Heath G; Kan, Alan; Litovsky, Ruth Y

2016-01-01

This study examined the effect of microphone placement on the interaural level differences (ILDs) available to bilateral cochlear implant (BiCI) users, and the subsequent effects on horizontal-plane sound localization. Virtual acoustic stimuli for sound localization testing were created individually for eight BiCI users by making acoustic transfer function measurements for microphones placed in the ear (ITE), behind the ear (BTE), and on the shoulders (SHD). The ILDs across source locations were calculated for each placement to analyze their effect on sound localization performance. Sound localization was tested using a repeated-measures, within-participant design for the three microphone placements. The ITE microphone placement provided significantly larger ILDs compared to BTE and SHD placements, which correlated with overall localization errors. However, differences in localization errors across the microphone conditions were small. The BTE microphones worn by many BiCI users in everyday life do not capture the full range of acoustic ILDs available, and also reduce the change in cue magnitudes for sound sources across the horizontal plane. Acute testing with an ITE placement reduced sound localization errors along the horizontal plane compared to the other placements in some patients. Larger improvements may be observed if patients had more experience with the new ILD cues provided by an ITE placement.

Headphone localization of speech stimuli

NASA Technical Reports Server (NTRS)

Begault, Durand R.; Wenzel, Elizabeth M.

1991-01-01

Recently, three dimensional acoustic display systems have been developed that synthesize virtual sound sources over headphones based on filtering by Head-Related Transfer Functions (HRTFs), the direction-dependent spectral changes caused primarily by the outer ears. Here, 11 inexperienced subjects judged the apparent spatial location of headphone-presented speech stimuli filtered with non-individualized HRTFs. About half of the subjects 'pulled' their judgements toward either the median or the lateral-vertical planes, and estimates were almost always elevated. Individual differences were pronounced for the distance judgements; 15 to 46 percent of stimuli were heard inside the head with the shortest estimates near the median plane. The results infer that most listeners can obtain useful azimuth information from speech stimuli filtered by nonindividualized RTFs. Measurements of localization error and reversal rates are comparable with a previous study that used broadband noise stimuli.

Postoperative granuloma after stapedectomy: is it destiny or avoidable?

PubMed

Batman, C; Oztürk, O; Ramadan, S S

2007-01-01

The aims of this study were (1) to investigate the pathophysiological characteristics of the middle ear mucoperiosteum against the caustic nature of the gastric content (GC), which consists largely of acid and pepsin components, and (2) to investigate the possible role of gastroesophageal reflux and postoperative vomiting (POV) in the etiology of poststapedectomy granuloma. 40 Spraque-Dawley rats of either sex and with a body weight of 200-300 g were used, and divided into different study groups: group 1: GC administration to the middle ear (n = 8); group 2: phosphate-buffered saline administration to the middle ear (n = 8); group 3: GC (pH: 2) administration in the presence of a Teflon piston (TP) (n = 6); group 4: phosphate-buffered saline administration in the presence of a TP (n = 6); group 5: GC administration in the presence of a wired piston (WP) (n = 6); group 6: phosphate- buffered saline administration in the presence of a WP (n = 6). GC was administrated to the middle ear cavities by way of the eustachian tube (ET). In order to overcome the pressure of the ET, a pump mechanism was used. The increased nasopharyngeal pressure caused a passive opening of the ET, and transferred a bolus to the middle ear. The animals were decapitated after 1 week, and the bullae were isolated. The tympanic bullae were serially cut and examined with light microscopy. In the saline controls, there was only a mild amount of polymorphonuclear cell (PMN) infiltration in the mildly thickened subepithelial space, indicating a less pronounced inflammation as compared to the gastric acid group. In the GC group, in addition to focal hemorrhage and severe subepithelial infiltration of PMNs, the middle ear mucosa was dramatically thickened with subepithelial edema and dilated capillaries. In the subepithelial tissue, retention cysts and granulation tissue were present. In the piston groups (TP and WP), there was extensive subepithelial inflammation and edema after GC and saline administrations. Granulation tissue filling the entire bulla around the piston segments was detected. The relationship between the administration of GC and middle ear inflammation, and the possible role of POV in the etiology of poststapedectomy granuloma are emphasized with our experimental study. The length of the TP may be considerably important to prevent POV which may lead to gastric reflux to the middle ear.

Understanding the translocation mechanism of PLGA nanoparticles across round window membrane into the inner ear: a guideline for inner ear drug delivery based on nanomedicine

PubMed Central

Zhang, Liping; Xu, Yuan; Cao, Wenjuan; Xie, Shibao; Wen, Lu; Chen, Gang

2018-01-01

Background The round window membrane (RWM) functions as the primary biological barrier for therapeutic agents in the inner ear via local application. Previous studies on inner ear nano-drug delivery systems mostly focused on their pharmacokinetics and distribution in the inner ear, but seldom on the interaction with the RWM. Clarifying the transport mechanism of nanoparticulate carriers across RWM will shed more light on the optimum design of nano-drug delivery systems intended for meeting demands for their clinical application. Methods The poly (lactic-co-glycolic acid) nanoparticles (PLGA NPs) encapsulating coumarin-6 were prepared by emulsifying solvent evaporation method. We utilized confocal laser scanning microscope (CLSM) in combination with transmission electron microscope to investigate the transport pathway of PLGA NPs in the RWM. Simultaneously, the concentration and time dependence of NPs across the RWM were also determined. The endocytic mechanism of NPs through this membrane interface was classically analyzed by means of various endocytic inhibitors. The intracellular location of NPs into lysosomes was evaluated using CLSM scanning microscope colocalization analysis. The Golgi-related inhibitors were employed to probe into the function of Golgi and endoplasmic reticulum (ER) in the discharge of NPs out of cells. Results PLGA NPs were herein transported through the RWM of a sandwich-like structure into the perilymph via the transcellular pathway. NPs were internalized predominantly via macropinocytosis and caveolin-mediated endocytic pathways. After being internalized, the endocytosed cargos were entrapped within the lysosomal compartments and/or the endoplasmic reticulum/Golgi apparatus which mediated the exocytotic release of NPs. Conclusion For the first time, we showed the translocation itinerary of NPs in RWM, providing a guideline for the rational fabrication of inner ear nanoparticulate carriers with better therapeutic effects. PMID:29403277

Requirements for FGF3 and FGF10 during inner ear formation.

PubMed

Alvarez, Yolanda; Alonso, Maria Teresa; Vendrell, Victor; Zelarayan, Laura Cecilia; Chamero, Pablo; Theil, Thomas; Bösl, Michael R; Kato, Shigeaki; Maconochie, Mark; Riethmacher, Dieter; Schimmang, Thomas

2003-12-01

Members of the fibroblast growth factor (FGF) gene family control formation of the body plan and organogenesis in vertebrates. FGF3 is expressed in the developing hindbrain and has been shown to be involved in inner ear development of different vertebrate species, including zebrafish, Xenopus, chick and mouse. In the mouse, insertion of a neomycin resistance gene into the Fgf3 gene via homologous recombination results in severe developmental defects during differentiation of the otic vesicle. We have addressed the precise roles of FGF3 and other FGF family members during formation of the murine inner ear using both loss- and gain-of-function experiments. We generated a new mutant allele lacking the entire FGF3-coding region but surprisingly found no evidence for severe defects either during inner ear development or in the mature sensory organ, suggesting the functional involvement of other FGF family members during its formation. Ectopic expression of FGF10 in the developing hindbrain of transgenic mice leads to the formation of ectopic vesicles, expressing some otic marker genes and thus indicating a role for FGF10 during otic vesicle formation. Expression analysis of FGF10 during mouse embryogenesis reveals a highly dynamic pattern of expression in the developing hindbrain, partially overlapping with FGF3 expression and coinciding with formation of the inner ear. However, FGF10 mutant mice have been reported to display only mild defects during inner ear differentiation. We thus created double mutant mice for FGF3 and FGF10, which form severely reduced otic vesicles, suggesting redundant roles of these FGFs, acting in combination as neural signals for otic vesicle formation.

Intra- and interspecific responses to Rafinesque’s big-eared bat (Corynorhinus rafinesquii) social calls.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Loeb, Susan, C.; Britzke, Eric, R.

Bats respond to the calls of conspecifics as well as to calls of other species; however, few studies have attempted to quantify these responses or understand the functions of these calls. We tested the response of Rafinesque’s big-eared bats (Corynorhinus rafinesquii) to social calls as a possible method to increase capture success and to understand the function of social calls. We also tested if calls of bats within the range of the previously designated subspecies differed, if the responses of Rafinesque’s big-eared bats varied with geographic origin of the calls, and if other species responded to the calls of C.more » rafinesquii. We recorded calls of Rafinesque’s big-eared bats at two colony roost sites in South Carolina, USA. Calls were recorded while bats were in the roosts and as they exited. Playback sequences for each site were created by copying typical pulses into the playback file. Two mist nets were placed approximately 50–500 m from known roost sites; the net with the playback equipment served as the Experimental net and the one without the equipment served as the Control net. Call structures differed significantly between the Mountain and Coastal Plains populations with calls from the Mountains being of higher frequency and longer duration. Ten of 11 Rafinesque’s big-eared bats were caught in the Control nets and, 13 of 19 bats of other species were captured at Experimental nets even though overall bat activity did not differ significantly between Control and Experimental nets. Our results suggest that Rafinesque’s big-eared bats are not attracted to conspecifics’ calls and that these calls may act as an intraspecific spacing mechanism during foraging.« less

[Analysis of the main components of inner ear antigens inducing autoimmune Meniere's disease in guinea pigs].

PubMed

Lu, Ling; Tan, Chang-Qiang; Cui, Yu-Gui; Ding, Gui-Peng; Ju, Xiao-Bin; Li, Yu-Jin; Cai, Wen-Jun

2008-08-01

To investigate the main components of inner ear antigens inducing autoimmune Meniere's disease (AIMD) in guinea pigs. The guinea pigs were immunized with isologous crude inner ear antigens (ICIEAg). Then, the hearing function was measured with auditory brainstem response (ABR), the vestibular function was measured with electronystagmography (including spontaneous nystagmus and caloric test), and inner ear histopathological changes were observed by inner ear celloidin section with haematoxylin-eosin staining and observed under light microscope. According to these results, the AIMD-model animals from non-AIMD-model ones were distinguished. The special antibodies against ICIEAg in sera were measured with ELISA. The antigen-antibody reactions against different components of ICIEAg were detected by Western blotting with sera of AIMD and non-AIMD guinea pigs respectively. Then, we analysed the contrast between them and found the main components of the ICIEAg that were positive reaction in AIMD guinea pigs and negative reaction in non-AIMD guinea pigs. The result of ELISA demonstrated that the sera of both the AIMD and non-AIMD guniea pigs contained the special antibodies against ICIEAg after immunized with ICIEAg. The difference of the amount of antibody against ICIEAg between AIMD guinea pig group and non-AIMD guinea pig group was not significant. Western blotting assay showed only the sera of AIMD guinea pig contained the antibodies against the specific antigens with the molecular of 68 000, 58 000, 42 000 and 28 000. ICIEAg contain many different components, the AIMD might only happen in the guinea pigs in which the special immunization against the main components that could induce this kind of disorder appeared. The inner ear antigens with molecular of 68 000, 58 000, 42 000 and 28 000 might be the main components inducing AIMD in guinea pigs.

Optimization of gene delivery methods in Xenopus laevis kidney (A6) and Chinese hamster ovary (CHO) cell lines for heterologous expression of Xenopus inner ear genes

PubMed Central

Ramirez-Gordillo, Daniel; Trujillo-Provencio, Casilda; Knight, V. Bleu; Serrano, Elba E.

2014-01-01

The Xenopus inner ear provides a useful model for studies of hearing and balance because it shares features with the mammalian inner ear, and because amphibians are capable of regenerating damaged mechanosensory hair cells. The structure and function of many proteins necessary for inner ear function have yet to be elucidated and require methods for analysis. To this end, we seek to characterize Xenopus inner ear genes outside of the animal model through heterologous expression in cell lines. As part of this effort, we aimed to optimize physical (electroporation), chemical (lipid-mediated; Lipofectamine™ 2000, Metafectene® Pro), and biological (viral-mediated; BacMam virus Cellular Lights™ Tubulin-RFP) gene delivery methods in amphibian (Xenopus; A6) cells and mammalian (Chinese hamster ovary (CHO)) cells. We successfully introduced the commercially available pEGFP-N3, pmCherry-N1, pEYFP-Tubulin, and Cellular Lights™ Tubulin-RFP fluorescent constructs to cells and evaluated their transfection or transduction efficiencies using the three gene delivery methods. In addition, we analyzed the transfection efficiency of a novel construct synthesized in our laboratory by cloning the Xenopus inner ear calcium-activated potassium channel β1 subunit, then subcloning the subunit into the pmCherry-N1 vector. Every gene delivery method was significantly more effective in CHO cells. Although results for the A6 cell line were not statistically significant, both cell lines illustrate a trend towards more efficient gene delivery using viral-mediated methods; however the cost of viral transduction is also much higher. Our findings demonstrate the need to improve gene delivery methods for amphibian cells and underscore the necessity for a greater understanding of amphibian cell biology. PMID:21959846

Evaluation of vestibular evoked myogenic potentials (VEMP) and electrocochleography for the diagnosis of Ménière's disease.

PubMed

Lamounier, Pauliana; de Souza, Thiago Silva Almeida; Gobbo, Debora Aparecida; Bahmad, Fayez

Ménière's disease (MD) is an inner ear disorder characterized by episodic vertigo, tinnitus, ear fullness, and fluctuating hearing. Its diagnosis can be especially difficult in cases where vestibular symptoms are present in isolation (vestibular MD). The definitive diagnosis is made histologically and can only be performed post-mortem, after analysis of the temporal bone. Endolymphatic hydrops is a histopathological finding of the disease and occurs more often in the cochlea and saccule, followed by the utricle and semicircular canals. Vestibular evoked myogenic potentials (VEMP) emerged as the method of assessment of vestibular function in 1994. Until then, there was no unique way of assessing saccular function and the inferior vestibular nerve. Given that the saccule is responsible for most cases of severe hydrops, VEMP appears as a new tool to assist in the diagnosis of MD. To evaluate the sensitivity and specificity of VEMP and electrocochleography (EcochG) in the diagnosis of definite MD compared with clinical diagnosis. The study includes 12 patients (24 ears) diagnosed with definite MD defined according to the clinical criteria proposed by the American Academy of Otolaryngology - Head and Neck Surgery (AAO-HNS) in 1995, as well as 12 healthy volunteers allocated to the control group (24 ears). A clinical diagnosis by the AAO-HNS criteria was considered as the gold standard. All patients underwent an otoneurological examination, including pure tone and speech audiometry, VEMP, and extratympanic EcochG. The sensitivity and specificity to detect the presence or absence of disease were calculated, as well as their 95% confidence intervals. The reliability of VEMP and EcochG in both ears was assessed using the kappa index. In both tests and in both ears, the ability to diagnose healthy cases was high, with specificity ranging from 84.6% to 100%. Moreover, the ability of the tests to diagnose the disease varied from low to moderate sensitivity, with values ranging from 37.5% to 63.6%. The agreement of both tests in the right ear, measured by the kappa coefficient, was equal to 0.54 (95% CI: 0.20-0.89), indicating a moderate agreement. In the left ear, that agreement was equal to 0.07 (95% CI: -0.33 to 0.46), indicating a weak correlation between the tests. The sensitivity of the VEMP for the right ear was 63.6% and for the left ear, 62.5%. The sensitivity of EcochG for the right ear was 63.6% and 37.5% for the left ear. The specificity of both tests was high, and the sensitivity of VEMP was higher than that of EcochG. Copyright © 2017 Associação Brasileira de Otorrinolaringologia e Cirurgia Cérvico-Facial. Published by Elsevier Editora Ltda. All rights reserved.

EARS2 mutations cause fatal neonatal lactic acidosis, recurrent hypoglycemia and agenesis of corpus callosum.

PubMed

Danhauser, Katharina; Haack, Tobias B; Alhaddad, Bader; Melcher, Marlen; Seibt, Annette; Strom, Tim M; Meitinger, Thomas; Klee, Dirk; Mayatepek, Ertan; Prokisch, Holger; Distelmaier, Felix

2016-06-01

Mitochondrial aminoacyl tRNA synthetases are essential for organelle protein synthesis. Genetic defects affecting the function of these enzymes may cause pediatric mitochondrial disease. Here, we report on a child with fatal neonatal lactic acidosis and recurrent hypoglycemia caused by mutations in EARS2, encoding mitochondrial glutamyl-tRNA synthetase 2. Brain ultrasound revealed agenesis of corpus callosum. Studies on patient-derived skin fibroblasts showed severely decreased EARS2 protein levels, elevated reactive oxygen species (ROS) production, and altered mitochondrial morphology. Our report further illustrates the clinical spectrum of the severe neonatal-onset form of EARS2 mutations. Moreover, in this case the live-cell parameters appeared to be more sensitive to mitochondrial dysfunction compared to standard diagnostics, which indicates the potential relevance of fibroblast studies in children with mitochondrial diseases.

Emergence of Unreported Stimuli into Imagery as a Function of Laterality of Presentation: A Replication and Extension of Research by Henley & Dixon.

ERIC Educational Resources Information Center

Mykel, Nan; Daves, Walter F.

1979-01-01

Right-handed subjects listened to music with one ear and received subliminal words in the other. The words emerged in subjects' reported imagery of the music more when the words were presented to the right ear (left brain hemisphere). A second experiment eliminated the music. (SJL)

Teaching and Using Audiation in Classroom Instruction and Applied Lessons with Advanced Students

ERIC Educational Resources Information Center

Hiatt, James S.; Cross, Sam

2006-01-01

A musical ear is widely accepted as an essential ingredient in the education of successful music students. Most music educators believe that without a well-developed ear, it's impossible for a musician to function on a professional level as a teacher, conductor, performer, or composer. The purpose of this article is to introduce the concept of…

The potential dysfunction of otolith organs in patients after mumps infection

PubMed Central

Tian, Liang; Han, Zhao; Wang, Jing; Chi, Fang-Lu

2017-01-01

Objective To investigate the relationship between mumps and the extent of hearing impairment and otolith organ damage. Methods A total of 27 patients with unilateral hearing impairment following mumps were enrolled. The degrees of hearing loss and otolith organ damage were confirmed by audiometric and vestibular evoked myogenic potential [VEMP] tests. All the results were compared and analyzed using Stata 13.0 software for Windows. Results The VEMP thresholds of the affected ears were significantly higher than those of the unaffected ears in both tests (cervical VEMP [cVEMP] test and ocular VEMP [oVEMP] test; p = 0.000 and 0.001, respectively). The mean cVEMP and oVEMP threshold values of the affected ears with hearing impairment for ≤10 years were significantly lower than those of affected ears with hearing impairment for >10 years [p = 0.009 and 0.004, respectively]. Conclusions Deafness resulting from mumps is usually profound and permanent, which indicates severe damage to the cochlea due to the disease. The functions of otolith organs in the vestibular system are also impaired. Over time, the function of the otolith organs or their neural pathway may suffer secondary damage. PMID:28746415

Evidence-based guidelines for recommending cochlear implantation for postlingually deafened adults.

PubMed

Leigh, Jaime R; Moran, Michelle; Hollow, Rodney; Dowell, Richard C

2016-01-01

Adult selection criteria for cochlear implantation have been developed based on analysis of the post-operative performance of a large group of postlingually deafened adults. Original criteria published in 2004 were reviewed and amended to reflect outcomes currently being achieved by implant recipients. Retrospective review of 12-month post-operative speech perception performance of adults implanted at the Eye and Ear Hospital, Melbourne, Australia. A total of 382 postlingually deafened adults, using a Freedom, Nucleus 5, or CI422 Slim Straight cochlear implant were used to create a comparative set of data. Revised guidelines suggest that adults with postlingual hearing loss can now be considered cochlear implant candidates if they obtain scores of up to 55% for open-set phonemes in quiet in the ear to be implanted. Functional benefit may vary depending on the recipients' contralateral hearing. This study supports the provision of cochlear implants to candidates with significant residual hearing when at least one ear meets the criterion outlined above. Patient-specific counseling is required to ensure the potential to benefit predicted by the current model is acceptable to the individual patient and their family. Counseling regarding functional benefit must take into consideration hearing in the contralateral ear.

Inner Ear Morphology in the Atlantic Molly Poecilia mexicana—First Detailed Microanatomical Study of the Inner Ear of a Cyprinodontiform Species

PubMed Central

Schulz-Mirbach, Tanja; Heß, Martin; Plath, Martin

2011-01-01

Background Fishes show an amazing diversity in hearing abilities, inner ear structures, and otolith morphology. Inner ear morphology, however, has not yet been investigated in detail in any member of the diverse order Cyprinodontiformes. We, therefore, studied the inner ear of the cyprinodontiform freshwater fish Poecilia mexicana by analyzing the position of otoliths in situ, investigating the 3D structure of sensory epithelia, and examining the orientation patterns of ciliary bundles of the sensory hair cells, while combining μ-CT analyses, scanning electron microscopy, and immunocytochemical methods. P. mexicana occurs in different ecotypes, enabling us to study the intra-specific variability (on a qualitative basis) of fish from regular surface streams, and the Cueva del Azufre, a sulfidic cave in southern Mexico. Results The inner ear of Poecilia mexicana displays a combination of several remarkable features. The utricle is connected rostrally instead of dorso-rostrally to the saccule, and the macula sacculi, therefore, is very close to the utricle. Moreover, the macula sacculi possesses dorsal and ventral bulges. The two studied ecotypes of P. mexicana showed variation mainly in the shape and curvature of the macula lagenae, in the curvature of the macula sacculi, and in the thickness of the otolithic membrane. Conclusions Our study for the first time provides detailed insights into the auditory periphery of a cyprinodontiform inner ear and thus serves a basis—especially with regard to the application of 3D techniques—for further research on structure-function relationships of inner ears within the species-rich order Cyprinodontiformes. We suggest that other poeciliid taxa, or even other non-poeciliid cyprinodontiforms, may display similar inner ear morphologies as described here. PMID:22110746

Inner ear morphology in the Atlantic molly Poecilia mexicana--first detailed microanatomical study of the inner ear of a cyprinodontiform species.

PubMed

Schulz-Mirbach, Tanja; Hess, Martin; Plath, Martin

2011-01-01

Fishes show an amazing diversity in hearing abilities, inner ear structures, and otolith morphology. Inner ear morphology, however, has not yet been investigated in detail in any member of the diverse order Cyprinodontiformes. We, therefore, studied the inner ear of the cyprinodontiform freshwater fish Poecilia mexicana by analyzing the position of otoliths in situ, investigating the 3D structure of sensory epithelia, and examining the orientation patterns of ciliary bundles of the sensory hair cells, while combining μ-CT analyses, scanning electron microscopy, and immunocytochemical methods. P. mexicana occurs in different ecotypes, enabling us to study the intra-specific variability (on a qualitative basis) of fish from regular surface streams, and the Cueva del Azufre, a sulfidic cave in southern Mexico. The inner ear of Poecilia mexicana displays a combination of several remarkable features. The utricle is connected rostrally instead of dorso-rostrally to the saccule, and the macula sacculi, therefore, is very close to the utricle. Moreover, the macula sacculi possesses dorsal and ventral bulges. The two studied ecotypes of P. mexicana showed variation mainly in the shape and curvature of the macula lagenae, in the curvature of the macula sacculi, and in the thickness of the otolithic membrane. Our study for the first time provides detailed insights into the auditory periphery of a cyprinodontiform inner ear and thus serves a basis--especially with regard to the application of 3D techniques--for further research on structure-function relationships of inner ears within the species-rich order Cyprinodontiformes. We suggest that other poeciliid taxa, or even other non-poeciliid cyprinodontiforms, may display similar inner ear morphologies as described here.

The ototoxic effect of intratympanic terbinafine applied in the middle ear of rats

PubMed Central

2013-01-01

Background Otomycosis is defined as an infection of the external ear canal with fungal agents. The treatment of the disease is cleansing and drying of the external ear canal, identification and treatment of any predisposing factors and application of topical antifungal agents. Terbinafine is used as an antifungal agent to treat otomycosis. We proposed to investigate the probable ototoxic effect of terbinafine solution on auditory brain stem response (ABR) and distortion product otoacoustic emission (DPOAE) when applied intratympanically in the middle ear of rats. Methods The experiment was performed on 30 female Wistar albino rats. Thirty animals were divided into three groups of 10 animals each. 1% terbinafine solution was administered to the first group (group T). The second group (group G) was administered 40 mg/ml gentamicin solution (ototoxic control). The third group (group S) was administered saline solution (negative control). Baseline DPOAE measurements and ABR testing from the left ears were obtained from the animals in all groups under general anesthesia. Ear solutions were applied in the middle ear intratympanically with a dental needle. Treatment was initiated after baseline measurements and repeated once every two days for fifteen days. Results Pre and post-treatment DPOAE responses for all tested frequencies of group T and Group S showed no statistically significant difference. However, the group G demonstrated a significant change in ABR thresholds and DPOAE responses. Conclusions Terbinafine solution is a broad spectrum antifungal agent effective in the treatment of otomycosis. The present study demonstrated that its direct administration in the middle ear of rats does not affect inner ear function as measured by ABR and DPOAE responses. PMID:23663536

Developmental evolutionary biology of the vertebrate ear: conserving mechanoelectric transduction and developmental pathways in diverging morphologies

NASA Technical Reports Server (NTRS)

Fritzsch, B.; Beisel, K. W.; Bermingham, N. A.

2000-01-01

This brief overview shows that a start has been made to molecularly dissect vertebrate ear development and its evolutionary conservation to the development of the insect hearing organ. However, neither the patterning process of the ear nor the patterning process of insect sensory organs is sufficiently known at the moment to provide more than a first glimpse. Moreover, hardly anything is known about otocyst development of the cephalopod molluscs, another triploblast lineage that evolved complex 'ears'. We hope that the apparent conserved functional and cellular components present in the ciliated sensory neurons/hair cells will also be found in the genes required for vertebrate ear and insect sensory organ morphogenesis (Fig. 3). Likewise, we expect that homologous pre-patterning genes will soon be identified for the non-sensory cell development, which is more than a blocking of neuronal development through the Delta/Notch signaling system. Generation of the apparently unique ear could thus represent a multiplication of non-sensory cells by asymmetric and symmetric divisions as well as modification of existing patterning process by implementing novel developmental modules. In the final analysis, the vertebrate ear may come about by increasing the level of gene interactions in an already existing and highly conserved interactive cascade of bHLH genes. Since this was apparently achieved in all three lineages of triploblasts independently (Fig. 3), we now need to understand how much of the morphogenetic cascades are equally conserved across phyla to generate complex ears. The existing mutations in humans and mice may be able to point the direction of future research to understand the development of specific cell types and morphologies in the formation of complex arthropod, cephalopod, and vertebrate 'ears'.

Effect of HIV Infection and Highly Active Antiretroviral Therapy on Hearing Function: A Prospective Case-Control Study From Cameroon.

PubMed

Fokouo, Jean Valentin F; Vokwely, Jean Espoir E; Noubiap, Jean Jacques N; Nouthe, Brice Enid; Zafack, Joseline; Minka Ngom, Esthelle Stéphanie; Dalil, Asmaou Bouba; Ngo Nyeki, Adèle-Rose; Bengono, Géneviève; Njock, Richard

2015-05-01

Human immunodeficiency virus (HIV) infection remains a major cause of morbidity and mortality worldwide. Many studies have found a higher prevalence of hearing impairment among HIV-positive individuals. To investigate the effect of HIV and highly active antiretroviral treatment (HAART) on the hearing function in a Cameroonian population. We conducted a prospective case-control study from March 1, 2012, through January 31, 2013. The study took place at the National Social Insurance Fund Hospital in Yaoundé, Cameroon, a public health facility. We included 90 HIV-positive case patients and 90 HIV-negative control patients aged 15 to 49 years without any history of hearing loss or treatment with a known ototoxic drug. The case group was further divided into 3 subgroups: 30 HAART-naive patients, 30 patients receiving first-line HAART, and 30 patients receiving second-line HAART. Hearing function was assessed by pure-tone audiometry and classified according to the criteria of the Bureau International d'Audio-Phonologie. Hearing loss due to HIV and HAART. The HIV-positive patients had more otologic symptoms (hearing loss, dizziness, tinnitus, and otalgia) than HIV-negative patients (41 vs 13, P = .04). There were 49 cases (27.2%) of hearing loss in the HIV-positive group vs 10 (5.6%) in the HIV-negative group (P = .04). Compared with HIV-negative individuals, the odds of hearing loss were higher among HIV-infected HAART-naive patients (right ear: odds ratio [OR], 6.7; 95% CI, 4.3-9.7; P = .004; left ear: OR, 6.2; 95% CI, 3.5-8.3; P = .006), patients receiving first-line HAART (right ear: OR, 5.6; 95% CI, 1.9-10.5; P = .01; left ear: OR, 12.5; 95% CI, 8.5-15.4; P < .001), and patients receiving second-line HAART (right ear: OR, 6.7; 95% CI, 3.3-9.6; P = .004; left ear: OR, 3.7; 95% CI, 3.0-5.0; P = .08). Hearing loss is more frequent in HIV-infected patients compared with uninfected patients. Therefore, HIV-infected patients need special audiologic care. Further studies are needed because controversy remains regarding the factors that lead to ear damage.

Low energy e-Ar momentum transfer cross-section

DOE Office of Scientific and Technical Information (OSTI.GOV)

Brennan, M.J.

1992-12-01

Recent work has shown that solutions of the Boltzmann equation which use the so called {open_quotes}two-term{close_quotes} approximation provide an inadequate description of the transverse diffusion of electrons in argon gas at low values of E/N, contrary to earlier evidence. Previous determinations of the momentum transfer cross section for argon from the analysis of transport data have used two-term codes in good faith. Progress towards the determination of a new cross section in the energy range O - 4 eV, including an analysis of the energy dependence of the uncertainty in the derived cross section is reported.

The Effects of Bug-in-Ear Coaching on Pre-Service Behavior Analysts' Use of Functional Communication Training.

PubMed

Artman-Meeker, Kathleen; Rosenberg, Nancy; Badgett, Natalie; Yang, Xueyan; Penney, Ashley

2017-09-01

Behavior analysts play an important role in supporting the behavior and learning of young children with disabilities in natural settings. However, there is very little research related specifically to developing the skills and competencies needed by pre-service behavior analysts. This study examined the effects of "bug-in-ear" (BIE) coaching on pre-service behavior analysts' implementation of functional communication training with pre-school children with autism in their classrooms. BIE coaching was associated with increases in the rate of functional communication training trials each intern initiated per session and in the fidelity with which interns implemented functional communication training. Adults created more intentional opportunities for children to communicate, and adults provided more systematic instruction around those opportunities.

Electrogenic transport and K+ ion channel expression by the human endolymphatic sac epithelium

PubMed Central

Kim, Sung Huhn; Kim, Bo Gyung; Kim, Jin Young; Roh, Kyung Jin; Suh, Michelle J.; Jung, JinSei; Moon, In Seok; Moon, Sung K.; Choi, Jae Young

2015-01-01

The endolymphatic sac (ES) is a cystic organ that is a part of the inner ear and is connected to the cochlea and vestibule. The ES is thought to be involved in inner ear ion homeostasis and fluid volume regulation for the maintenance of hearing and balance function. Many ion channels, transporters, and exchangers have been identified in the ES luminal epithelium, mainly in animal studies, but there has been no functional study investigating ion transport using human ES tissue. We designed the first functional experiments on electrogenic transport in human ES and investigated the contribution of K+ channels in the electrogenic transport, which has been rarely identified, even in animal studies, using electrophysiological/pharmacological and molecular biological methods. As a result, we identified functional and molecular evidence for the essential participation of K+ channels in the electrogenic transport of human ES epithelium. The identified K+ channels involved in the electrogenic transport were KCNN2, KCNJ14, KCNK2, and KCNK6, and the K+ transports via those channels are thought to play an important role in the maintenance of the unique ionic milieu of the inner ear fluid. PMID:26655723

Functional recovery in the avian ear after hair cell regeneration.

PubMed

Smolders, J W

1999-01-01

Trauma to the inner ear in birds, due to acoustic overstimulation or ototoxic aminoglycosides, can lead to hair cell loss which is followed by regeneration of new hair cells. These processes are paralleled by hearing loss followed by significant functional recovery. After acoustic trauma, functional recovery is rapid and nearly complete. The early and major part of functional recovery after sound trauma occurs before regenerated hair cells become functional. Even very intense sound trauma causes loss of only a proportion of the hair cell population, mainly so-called short hair cells residing on the abneural mobile part of the avian basilar membrane. Uncoupling of the tectorial membrane from the hair cells during sound overexposure may serve as a protection mechanism. The rapid functional recovery after sound trauma appears not to be associated with regeneration of the lost hair cells, but with repair processes involving the surviving hair cells. Small residual functional deficits after recovery are most likely associated with the missing upper fibrous layer of the tectorial membrane which fails to regenerate after sound trauma. After aminoglycoside trauma, functional recovery is slower and parallels the structural regeneration more closely. Aminoglycosides cause damage to both types of hair cells, starting at the basal (high frequency) part of the basilar papilla. However, functional hearing loss and recovery also occur at lower frequencies, associated with areas of the papilla where hair cells survive. Functional recovery in these low frequency areas is complete, whereas functional recovery in high frequency areas with complete hair cell loss is incomplete, despite regeneration of the hair cells. Permanent residual functional deficits remain. This indicates that in low frequency regions functional recovery after aminoglycosides involves repair of nonlethal injury to hair cells and/or hair cell-neural synapses. In the high frequency regions functional recovery involves regenerated hair cells. The permanent functional deficits after the regeneration process in these areas are most likely associated with functional deficits in the regenerated hair cells or shortcomings in the synaptic reconnections of nerve fibers with the regenerated hair cells. In conclusion, the avian inner ear appears to be much more resistant to trauma than the mammalian ear and possesses a considerable capacity for functional recovery based on repair processes along with its capacity to regenerate hair cells. The functional recovery in areas with regenerated hair cells is considerable but incomplete.

Model-oriented review and multi-body simulation of the ossicular chain of the human middle ear.

PubMed

Volandri, G; Di Puccio, F; Forte, P; Manetti, S

2012-11-01

The ossicular chain of the human middle ear has a key role in sound conduction since it transfers vibrations from the tympanic membrane to the cochlea, connecting the outer and the inner part of the hearing organ. This study reports firstly a description of the main anatomical features of the middle ear to introduce a detailed survey of its biomechanics, focused on model development, with a collection of geometric, inertial and mechanical/material parameters. The joint issues are particularly discussed from the perspective of developing a model of the middle ear both explanatory and predictive. Such a survey underlines the remarkable dispersion of data, due also to the lack of a standardization of the experimental techniques and conditions. Subsequently, a 3D multi-body model of the ossicular chain and other structures of the middle ear is described. Such an approach is justified as the ossicles were proven to behave as rigid bodies in the human hearing range and was preferred to the more widely used finite element one as it simplifies the model development and improves joint modeling. The displacement of the umbo (a reference point of the tympanic membrane) in the 0.3-6kHz frequency range was defined as input of the model, while the stapes footplate displacement as output. A parameter identification procedure was used to find parameter values for reproducing experimental and numerical reference curves taken from the literature. This simple model might represent a valid alternative to more complex models and might provide a useful tool to simulate pathological/post-surgical/post-traumatic conditions and evaluate ossicular replacement prostheses. Copyright © 2012 IPEM. Published by Elsevier Ltd. All rights reserved.

Transfer of free fillet lateral arm flap for facial reconstruction.

PubMed

Bayram, Fazli Cengiz; Dadaci, Mehmet; Ince, Bilsev; Altuntas, Zeynep

2014-07-01

We describe a 16-year-old male patient who had a major right facial degloving injury resulting in a soft-tissue defect with exposed zygoma as well as temporal and frontal bones. Multiple operations were undertaken in a staged manner for reconstruction. Lateral arm free fillet flap transfer was initially performed with fixation of bones with miniplates, which is followed by flap debulking, lateral canthopexy, scalp tissue expansion for hairline reconstruction, as well as ear reconstruction with costal cartilage and local flap techniques. After a follow-up period of 2 years, a good and impressive reconstructive result was achieved through the use of multiple contemporary reconstructive procedures after a successful free fillet flap transfer from an amputated part.

Mechanisms of Cochlear Stimulation Through the Round Window

NASA Astrophysics Data System (ADS)

Lukashkin, Andrei N.; Weddell, Thomas; Russell, Ian J.

2011-11-01

The round window membrane (RW) functions as a pressure relief valve in conventional hearing allowing structures of the middle ear to move. Investigations in recent years have shown that middle ear implants can be used to stimulate the cochlea via the RW. Isolated clinical uses of this technique have been applied but more thorough theoretical and empirical studies are required. Using guinea pigs as test subjects we have investigated physiological effects of RW stimulation using a simulation of active middle ear prosthesis, a cylindrical neodymium iron boron disk magnet placed upon the RW which can be stimulated by an electromagnetic coil positioned in close proximity to the magnet.

Panel 2: Anatomy (Eustachian Tube, Middle Ear, and Mastoid-Anatomy, Physiology, Pathophysiology, and Pathogenesis).

PubMed

Alper, Cuneyt M; Luntz, Michal; Takahashi, Haruo; Ghadiali, Samir N; Swarts, J Douglas; Teixeira, Miriam S; Csákányi, Zsuzsanna; Yehudai, Noam; Kania, Romain; Poe, Dennis S

2017-04-01

Objective In this report, we review the recent literature (ie, past 4 years) to identify advances in our understanding of the middle ear-mastoid-eustachian tube system. We use this review to determine whether the short-term goals elaborated in the last report were achieved, and we propose updated goals to guide future otitis media research. Data Sources PubMed, Web of Science, Medline. Review Methods The panel topic was subdivided, and each contributor performed a literature search within the given time frame. The keywords searched included middle ear, eustachian tube, and mastoid for their intersection with anatomy, physiology, pathophysiology, and pathology. Preliminary reports from each panel member were consolidated and discussed when the panel met on June 11, 2015. At that meeting, the progress was evaluated and new short-term goals proposed. Conclusions Progress was made on 13 of the 20 short-term goals proposed in 2011. Significant advances were made in the characterization of middle ear gas exchange pathways, modeling eustachian tube function, and preliminary testing of treatments for eustachian tube dysfunction. Implications for Practice In the future, imaging technologies should be developed to noninvasively assess middle ear/eustachian tube structure and physiology with respect to their role in otitis media pathogenesis. The new data derived from these structure/function experiments should be integrated into computational models that can then be used to develop specific hypotheses concerning otitis media pathogenesis and persistence. Finally, rigorous studies on medical or surgical treatments for eustachian tube dysfunction should be undertaken.

Identifying Otosclerosis with Aural Acoustical Tests of Absorbance, Group Delay, Acoustic Reflex Threshold, and Otoacoustic Emissions.

PubMed

Keefe, Douglas H; Archer, Kelly L; Schmid, Kendra K; Fitzpatrick, Denis F; Feeney, M Patrick; Hunter, Lisa L

2017-10-01

Otosclerosis is a progressive middle-ear disease that affects conductive transmission through the middle ear. Ear-canal acoustic tests may be useful in the diagnosis of conductive disorders. This study addressed the degree to which results from a battery of ear-canal tests, which include wideband reflectance, acoustic stapedius muscle reflex threshold (ASRT), and transient evoked otoacoustic emissions (TEOAEs), were effective in quantifying a risk of otosclerosis and in evaluating middle-ear function in ears after surgical intervention for otosclerosis. To evaluate the ability of the test battery to classify ears as normal or otosclerotic, measure the accuracy of reflectance in classifying ears as normal or otosclerotic, and evaluate the similarity of responses in normal ears compared with ears after surgical intervention for otosclerosis. A quasi-experimental cross-sectional study incorporating case control was used. Three groups were studied: one diagnosed with otosclerosis before corrective surgery, a group that received corrective surgery for otosclerosis, and a control group. The test groups included 23 ears (13 right and 10 left) with normal hearing from 16 participants (4 male and 12 female), 12 ears (7 right and 5 left) diagnosed with otosclerosis from 9 participants (3 male and 6 female), and 13 ears (4 right and 9 left) after surgical intervention from 10 participants (2 male and 8 female). Participants received audiometric evaluations and clinical immittance testing. Experimental tests performed included ASRT tests with wideband reference signal (0.25-8 kHz), reflectance tests (0.25-8 kHz), which were parameterized by absorbance and group delay at ambient pressure and at swept tympanometric pressures, and TEOAE tests using chirp stimuli (1-8 kHz). ASRTs were measured in ipsilateral and contralateral conditions using tonal and broadband noise activators. Experimental ASRT tests were based on the difference in wideband-absorbed sound power before and after presenting the activator. Diagnostic accuracy to classify ears as otosclerotic or normal was quantified by the area under the receiver operating characteristic curve (AUC) for univariate and multivariate reflectance tests. The multivariate predictor used a small number of input reflectance variables, each having a large AUC, in a principal components analysis to create independent variables and followed by a logistic regression procedure to classify the test ears. Relative to the results in normal ears, diagnosed otosclerosis ears more frequently showed absent TEOAEs and ASRTs, reduced ambient absorbance at 4 kHz, and a different pattern of tympanometric absorbance and group delay (absorbance increased at 2.8 kHz at the positive-pressure tail and decreased at 0.7-1 kHz at the peak pressure, whereas group delay decreased at positive and negative-pressure tails from 0.35-0.7 kHz, and at 2.8-4 kHz at positive-pressure tail). Using a multivariate predictor with three reflectance variables, tympanometric reflectance (AUC = 0.95) was more accurate than ambient reflectance (AUC = 0.88) in classifying ears as normal or otosclerotic. Reflectance provides a middle-ear test that is sensitive to classifying ears as otosclerotic or normal, which may be useful in clinical applications. American Academy of Audiology

Ear nose throat manifestations in hypoidrotic ectodermal dysplasia.

PubMed

Callea, Michele; Teggi, Roberto; Yavuz, Izzet; Tadini, Gianluca; Priolo, Manuela; Crovella, Sergio; Clarich, Gabriella; Grasso, Domenico Leonardo

2013-11-01

The ectodermal dysplasias (EDs) are a large and complex group of inherited disorders. In various combinations, they all share anomalies in ectodermal derived structures: hair, teeth, nails and sweat gland function. Clinical overlap is present among EDs. Few causative genes have been identified, to date. Altered gene expression is not limited to the ectoderm but a concomitant effect on developing mesenchymal structures, with modification of ectodermal-mesenchymal signaling, takes place. The two major categories of ED include the hidrotic and hypohidrotic form, the latter more frequent; they differentiate each other for the presence or absence of sweat glands. We report Ear Nose Throat manifestations of ED, linked to the reduction of mucous glands in the nasal fossae with reduced ciliar function, and decrease salivary glands function. Often patients report an increased rate of infections of the upper respiratory tract and of the ear. Nasal obstruction due to the presence of nasal crusting, hearing loss and throat hoarseness are the most represented symptoms. Environmental measures, including a correct air temperature and humidification, is mandatory above all in subjects affected by hypohidrotic form. Copyright © 2013 Elsevier Ireland Ltd. All rights reserved.

On the frequency dependence of the otoacoustic emission latency in hypoacoustic and normal ears

NASA Astrophysics Data System (ADS)

Sisto, R.; Moleti, A.

2002-01-01

Experimental measurements of the otoacoustic emission (OAE) latency of adult subjects have been obtained, as a function of frequency, by means of wavelet time-frequency analysis based on the iterative application of filter banks. The results are in agreement with previous OAE latency measurements by Tognola et al. [Hear. Res. 106, 112-122 (1997)], as regards both the latency values and the frequency dependence, and seem to be incompatible with the steep 1/f law that is predicted by scale-invariant full cochlear models. The latency-frequency relationship has been best fitted to a linear function of the cochlear physical distance, using the Greenwood map, and to an exponential function of the cochlear distance, for comparison with derived band ABR latency measurements. Two sets of ears [94 audiometrically normal and 42 impaired with high-frequency (f>3 kHz) hearing loss] have been separately analyzed. Significantly larger average latencies were found in the impaired ears in the mid-frequency range. Theoretical implications of these findings on the transmission of the traveling wave are discussed.

Pre- and postoperative memory of dichotically presented words in patients with complex partial seizures.

PubMed

Christianson, S A; Nilsson, L G; Silfvenius, H

1989-01-01

Dichotic listening tests were used to determine cerebral hemisphere memory functions in patients with complex partial seizures before, 10 days after, and 1-3 yr after right (RTE) or left (LTE) temporal-lobe excisions. Control subjects were also tested on two occasions. The tests consisted of presenting a series of 12-word lists and 7-word lists alternately to the two ears while backward speech was presented to the other ear. Measures of immediate free recall, final free recall, final cued recall, and serial recall were employed. The results revealed: (a) that both groups of patients were inferior the control group in tests tapping long-term memory functions rather than short-term memory functions, (b) a right-ear advantage for RTE patients at postoperative testing, (c) that the LTE group was more affected by surgery than the RTE group, and (d) a general improvement in recall performance from early to late postoperative testing. Taken together, these results indicate that the present dichotic test can be used as a non-invasive hemisphere memory test to complement invasive techniques for diagnosis of patients considered for epilepsy surgery.

Usher proteins in inner ear structure and function.

PubMed

Ahmed, Zubair M; Frolenkov, Gregory I; Riazuddin, Saima

2013-11-01

Usher syndrome (USH) is a neurosensory disorder affecting both hearing and vision in humans. Linkage studies of families of USH patients, studies in animals, and characterization of purified proteins have provided insight into the molecular mechanisms of hearing. To date, 11 USH proteins have been identified, and evidence suggests that all of them are crucial for the function of the mechanosensory cells of the inner ear, the hair cells. Most USH proteins are localized to the stereocilia of the hair cells, where mechano-electrical transduction (MET) of sound-induced vibrations occurs. Therefore, elucidation of the functions of USH proteins in the stereocilia is a prerequisite to understanding the exact mechanisms of MET.

Investigating Science Student Teachers' Ideas about Function and Anatomical Form of Two Human Sensory Organs, the Eye and the Ear

ERIC Educational Resources Information Center

Kunt, Halil

2016-01-01

The purpose of this research was to determine science student teachers' level of knowledge about the anatomical structure of two sensory organs, the eye and the ear, in addition to vision and hearing processes. Conducted with 86 science student teachers, research utilized drawing methods and open-ended questions as data collection instruments. The…

A physiological frequency-position map of the chinchilla cochlea.

PubMed

Müller, Marcus; Hoidis, Silvi; Smolders, Jean W T

2010-09-01

Accumulating evidence indicates that mammalian cochlear frequency-position maps (location of maximum vibration of the basilar membrane as a function of frequency) depend on the physiological condition of the inner ear. Cochlear damage desensitizes the ear, after the damage the original location of maximum vibration is tuned to a lower sound frequency. This suggests that frequency-position maps, derived from such desensitized ears, are shifted to lower frequencies, corresponding to a shift of the basilar membrane vibration pattern towards the base for a given stimulus frequency. To test this hypothesis, we re-mapped the cochlear frequency-position map in the chinchilla. We collected frequency-position data from chinchillas in normal physiological condition ("physiological map") and compared these to data previously established from sound overexposed ears ("anatomical map"). The characteristic frequency (CF) of neurons in the cochlear nucleus was determined. Horse-radish peroxidase (HRP) or biocytin (BCT) were injected iontophoretically to trace auditory nerve fibers towards their innervation site in the organ of Corti. The relationship between distance from the base (d, percent) and frequency (f, kHz) was described best by a simple exponential function: d = 61.2 - 42.2 x log(f). The slope of the function was 2.55 mm/octave. Compared to the "anatomical map", the "physiological map" was shifted by about 0.3 octaves to higher frequencies corresponding to a shift of the basilar membrane vibration pattern of 0.8 mm towards the apex for a given stimulus frequency. Our findings affirm that frequency-position maps in the mammalian cochlea depend on the condition of the inner ear. Damage-induced desensitization in mammalian inner ears results in similar shifts of CF (about 0.5 octaves) but different shifts of the maximum of the vibration pattern towards the base at given frequencies, dependent on the mapping constant of the species, longer basilar membranes showing a larger basal shift. Furthermore, the results substantiate the notion that "crowding" at lower frequencies appears to be a specialization rather than a general feature. Copyright (c) 2010 Elsevier B.V. All rights reserved.

Deletion of a conserved regulatory element required for Hmx1 expression in craniofacial mesenchyme in the dumbo rat: a newly identified cause of congenital ear malformation

PubMed Central

Quina, Lely A.; Kuramoto, Takashi; Luquetti, Daniela V.; Cox, Timothy C.; Serikawa, Tadao; Turner, Eric E.

2012-01-01

SUMMARY Hmx1 is a homeodomain transcription factor expressed in the developing eye, peripheral ganglia, and branchial arches of avian and mammalian embryos. Recent studies have identified a loss-of-function allele at the HMX1 locus as the causative mutation in the oculo-auricular syndrome (OAS) in humans, characterized by ear and eye malformations. The mouse dumbo (dmbo) mutation, with similar effects on ear and eye development, also results from a loss-of-function mutation in the Hmx1 gene. A recessive dmbo mutation causing ear malformation in rats has been mapped to the chromosomal region containing the Hmx1 gene, but the nature of the causative allele is unknown. Here we show that dumbo rats and mice exhibit similar neonatal ear and eye phenotypes. In midgestation embryos, dumbo rats show a specific loss of Hmx1 expression in neural-crest-derived craniofacial mesenchyme (CM), whereas Hmx1 is expressed normally in retinal progenitors, sensory ganglia and in CM, which is derived from mesoderm. High-throughput resequencing of 1 Mb of rat chromosome 14 from dmbo/dmbo rats, encompassing the Hmx1 locus, reveals numerous divergences from the rat genomic reference sequence, but no coding changes in Hmx1. Fine genetic mapping narrows the dmbo critical region to an interval of ∼410 kb immediately downstream of the Hmx1 transcription unit. Further sequence analysis of this region reveals a 5777-bp deletion located ∼80 kb downstream in dmbo/dmbo rats that is not apparent in 137 other rat strains. The dmbo deletion region contains a highly conserved domain of ∼500 bp, which is a candidate distal enhancer and which exhibits a similar relationship to Hmx genes in all vertebrate species for which data are available. We conclude that the rat dumbo phenotype is likely to result from loss of function of an ultraconserved enhancer specifically regulating Hmx1 expression in neural-crest-derived CM. Dysregulation of Hmx1 expression is thus a candidate mechanism for congenital ear malformation, most cases of which remain unexplained. PMID:22736458

Chondrocutaneous helix rim advancement flap: two classical and two new modifications for very large defects of the ear.

PubMed

Valesky, E M; Kaufmann, R; Meissner, M

2015-11-01

The plastic reconstruction of the ear after microscopically controlled tumor surgery is a particular challenge. The chondrocutaneous helix rim advancement flap (CHRAF) is perfectly suited for the repair of different defects of the helix and even defects beyond. Here, we describe two known and two new modifications of the CHRAF that enlarge the scope of application in tumor surgery of the ear. We demonstrate the different techniques and practical application of the repair and evaluate the benefits and limitations. The CHRAF and its modifications is an excellent method for repair of various defects of the helical region of the ear. The CHRAF and its modifications proves to be an good alternative to other methods of closure by preserving the anatomical contour and mechanical and acoustic functions in a single-staged procedure with excellent aesthetic results. The two new modifications we introduced here, enlarge the known armentarium for very large defects of the upper pole and the mid-helix of the ear. © 2014 European Academy of Dermatology and Venereology.

SENSORY HAIR CELL REGENERATION IN THE ZEBRAFISH LATERAL LINE

PubMed Central

Lush, Mark E.; Piotrowski, Tatjana

2014-01-01

Damage or destruction of sensory hair cells in the inner ear leads to hearing or balance deficits that can be debilitating, especially in older adults. Unfortunately, the damage is permanent, as regeneration of the inner ear sensory epithelia does not occur in mammals. Zebrafish and other non-mammalian vertebrates have the remarkable ability to regenerate sensory hair cells and understanding the molecular and cellular basis for this regenerative ability will hopefully aid us in designing therapies to induce regeneration in mammals. Zebrafish not only possess hair cells in the ear but also in the sensory lateral line system. Hair cells in both organs are functionally analogous to hair cells in the inner ear of mammals. The lateral line is a mechanosensory system found in most aquatic vertebrates that detects water motion and aids in predator avoidance, prey capture, schooling and mating. Although hair cell regeneration occurs in both the ear and lateral line, most research to date has focused on the lateral line due to its relatively simple structure and accessibility. Here we review the recent discoveries made during the characterization of hair cell regeneration in zebrafish. PMID:25045019

Distinct Genetic Architectures for Male and Female Inflorescence Traits of Maize

PubMed Central

Brown, Patrick J.; Upadyayula, Narasimham; Mahone, Gregory S.; Tian, Feng; Bradbury, Peter J.; Myles, Sean; Holland, James B.; Flint-Garcia, Sherry; McMullen, Michael D.; Buckler, Edward S.; Rocheford, Torbert R.

2011-01-01

We compared the genetic architecture of thirteen maize morphological traits in a large population of recombinant inbred lines. Four traits from the male inflorescence (tassel) and three traits from the female inflorescence (ear) were measured and studied using linkage and genome-wide association analyses and compared to three flowering and three leaf traits previously studied in the same population. Inflorescence loci have larger effects than flowering and leaf loci, and ear effects are larger than tassel effects. Ear trait models also have lower predictive ability than tassel, flowering, or leaf trait models. Pleiotropic loci were identified that control elongation of ear and tassel, consistent with their common developmental origin. For these pleiotropic loci, the ear effects are larger than tassel effects even though the same causal polymorphisms are likely involved. This implies that the observed differences in genetic architecture are not due to distinct features of the underlying polymorphisms. Our results support the hypothesis that genetic architecture is a function of trait stability over evolutionary time, since the traits that changed most during the relatively recent domestication of maize have the largest effects. PMID:22125498

Ear malformations, hearing loss and hearing rehabilitation in children with Treacher Collins syndrome.

PubMed

Rosa, Francisco; Coutinho, Miguel Bebiano; Ferreira, João Pinto; Sousa, Cecilia Almeida

2016-01-01

The aim of this study was to assess the main ear malformations, hearing loss and auditory rehabilitation in children with Treacher Collins syndrome. We performed a retrospective study of 9 children with Treacher Collins syndrome treated in a central hospital between January 2003 and January 2013. This study showed a high incidence of malformations of the outer and middle ear, such as microtia, atresia or stenosis of the external auditory canal, hypoplastic middle ear cavity, dysmorphic or missing ossicular chain. Most patients had bilateral hearing loss of moderate or high degree. In the individuals studied, there was functional improvement in patients with bone-anchored hearing aids in relation to conventional hearing aids by bone conduction. Treacher Collins syndrome is characterized by bilateral malformations of the outer and middle ear. Hearing rehabilitation in these children is of utmost importance, and bone-anchored hearing aids is the method of choice. Copyright © 2014 Elsevier España, S.L.U. y Sociedad Española de Otorrinolaringología y Cirugía de Cabeza y Cuello. All rights reserved.

Stress-Responsive Mitogen-Activated Protein Kinases Interact with the EAR Motif of a Poplar Zinc Finger Protein and Mediate Its Degradation through the 26S Proteasome1[W][OA

PubMed Central

Hamel, Louis-Philippe; Benchabane, Meriem; Nicole, Marie-Claude; Major, Ian T.; Morency, Marie-Josée; Pelletier, Gervais; Beaudoin, Nathalie; Sheen, Jen; Séguin, Armand

2011-01-01

Mitogen-activated protein kinases (MAPKs) contribute to the establishment of plant disease resistance by regulating downstream signaling components, including transcription factors. In this study, we identified MAPK-interacting proteins, and among the newly discovered candidates was a Cys-2/His-2-type zinc finger protein named PtiZFP1. This putative transcription factor belongs to a family of transcriptional repressors that rely on an ERF-associated amphiphilic repression (EAR) motif for their repression activity. Amino acids located within this repression motif were also found to be essential for MAPK binding. Close examination of the primary protein sequence revealed a functional bipartite MAPK docking site that partially overlaps with the EAR motif. Transient expression assays in Arabidopsis (Arabidopsis thaliana) protoplasts suggest that MAPKs promote PtiZFP1 degradation through the 26S proteasome. Since features of the MAPK docking site are conserved among other EAR repressors, our study suggests a novel mode of defense mechanism regulation involving stress-responsive MAPKs and EAR repressors. PMID:21873571

Local treatment of the inner ear: a study of three different polymers aimed for middle ear administration.

PubMed

Engmér Berglin, Cecilia; Videhult Pierre, Pernilla; Ekborn, Andreas; Bramer, Tobias; Edsman, Katarina; Hultcrantz, Malou; Laurell, Göran

2015-01-01

A formulation based on sodium hyaluronate (NaHYA) was the most promising candidate vehicle for intra-tympanic drug administration regarding conductive hearing loss, inflammatory reactions, and elimination. Recent advances in inner ear research support the idea of using the middle ear cavity for drug administration to target the inner ear. This paper presents rheological and safety assessments of three candidate polymer formulations for intra-tympanic drug administration. The formulations were based on sodium carboxymethyl cellulose (NaCMC), sodium hyaluronate (NaHYA), and poloxamer 407 (POL). Rheological studies were performed with a controlled rate instrument of the couette type. Safety studies were performed in guinea pigs subjected to an intra-tympanic injection of the formulations. Hearing function was explored with ABR before and 1, 2, and 3 weeks after the injection. Elimination of the formulations marked with coal was explored with an endoscopic digital camera 1, 2, and 3 weeks after injection. Middle and inner ear morphology was examined with light microscopy 6 days after injection. The results speak in favor of NaHYA, since it did not cause prolonged hearing threshold elevations. The results of the elimination and morphological investigations support the conclusion of NaHYA being the most promising candidate for intra-tympanic administration.

Inflation-deflation test as a predictor of aditus patency in patients with chronic suppurative otitis media.

PubMed

Kurien, Regi; Chrisolyte, Shipra; Rupa, V

2009-09-01

To assess eustachian tubal function (ETF) preoperatively in patients with chronic suppurative otitis media (CSOM) with central perforation by performing the inflation-deflation test. To correlate the results of the inflation-deflation test with the finding of aditus patency or block in patients with CSOM STUDY DESIGN: Prospective, cohort Tertiary care hospital Eighty adult patients with chronic suppurative otitis media and central perforation were recruited into the study. There were 45 males and 35 females. All patients underwent preoperative inflation-deflation test followed by cortical mastoidectomy and tympanoplasty. The patency of the aditus was assessed intraoperatively. Equalization of pressure on inflation-deflation test and intraoperative assessment of aditus patency Of a total of 80 patients, 49 patients were found to have discharging ears and 31 had dry ears at the time of surgery. In dry ears the inflation-deflation test had a sensitivity of 93% in predicting aditus patency although the specificity was lower at 67%. In discharging ears the sensitivity in predicting aditus patency was 72% and the specificity was 67%. The eustachian tube inflation-deflation test is a sensitive test for predicting aditus patency in patients with dry ears but less so in patients with discharging ears. Hence, it could be used in the former to avoid unnecessary exploration of the mastoid.

Production of nuclear transfer embryos by using somatic cells isolated from milk in buffalo (Bubalus bubalis).

PubMed

Golla, K; Selokar, N L; Saini, M; Chauhan, M S; Manik, R S; Palta, P; Singla, S K

2012-10-01

Somatic cells in milk are a potential source of nuclei for nuclear transfer to produce genetically identical animals; this is especially important in animals that are susceptible to risks of bacterial infection on biopsy collection. In this study, a minimum of 10 milk samples were collected from each of the three buffaloes representing Murrah breed. All the samples were processed immediately and cell colonies were obtained. Cell colonies from one buffalo (MU-442) survived beyond 10 passages and were evaluated by fluorescence microscopy and used in nuclear transfer experiments. In culture, these cells expressed vimentin, indicating they were of fibroblast origin similar to ear cells. We compared the effectiveness of cloning using those milk-derived fibroblast (MDF) cells and fibroblast cells derived from the ear derived fibroblast (EDF). Fusion and cleavage rates of MDF-NT and EDF-NT embryos were found to be similar (92.43 ± 1.28% vs 94.98 ± 1.24%, and 80.27 ± 1.75% vs 84.56 ± 3.73%, respectively; p > 0.01); however, development to blastocyst stage and total cell number was higher for EDF-NT embryos (50.24 ± 2.54%, 227.14 ± 13.04, respectively, p < 0.01), than for MDF-NT embryos (16.44 ± 0.75%, 170.57 ± 4.50 respectively). We conclude that somatic cells from milk can be cultured effectively and used as nucleus donor to produce cloned blastocyst-stage embryos. © 2012 Blackwell Verlag GmbH.

Hemispheric dominance and cell phone use.

PubMed

Seidman, Michael D; Siegel, Bianca; Shah, Priyanka; Bowyer, Susan M

2013-05-01

A thorough understanding of why we hold a cell phone to a particular ear may be of importance when studying the impact of cell phone safety. To determine if there is an obvious association between sidedness of cell phone use and auditory hemispheric dominance (AHD) or language hemispheric dominance (LHD). It is known that 70% to 95% of the population are right-handed, and of these, 96% have left-brain LHD. We have observed that most people use their cell phones in their right ear. An Internet survey was e-mailed to individuals through surveymonkey.com. The survey used a modified Edinburgh Handedness Inventory protocol. Sample questions surveyed which hand was used to write with, whether the right or left ear was used for phone conversations, as well as whether a brain tumor was present. General community. An Internet survey was randomly e-mailed to 5000 individuals selected from an otology online group, patients undergoing Wada testing and functional magnetic resonance imaging, as well as persons on the university listserv, of which 717 surveys were completed. Determination of hemispheric dominance based on preferred ear for cell phone use. A total of 717 surveys were returned. Ninety percent of the respondents were right handed, and 9% were left handed. Sixty-eight percent of the right-handed people used the cell phone in their right ear, 25% in the left ear, and 7% had no preference. Seventy-two of the left-handed respondents used their left ear, 23% used their right ear, and 5% had no preference. Cell phone use averaged 540 minutes per month over the past 9 years. An association exists between hand dominance laterality of cell phone use (73%) and our ability to predict hemispheric dominance. Most right-handed people have left-brain LHD and use their cell phone in their right ear. Similarly, most left-handed people use their cell phone in their left ear. Our study suggests that AHD may differ from LHD owing to the difference in handedness and cell phone ear use. Literature suggests a possible relationship between cell phone use and cancer. The fact that few tumors were identified in this population does not rule out an association.

Influence of EARLI1-like genes on flowering time and lignin synthesis of Arabidopsis thaliana.

PubMed

Shi, Y; Zhang, X; Xu, Z-Y; Li, L; Zhang, C; Schläppi, M; Xu, Z-Q

2011-09-01

EARLI1 encodes a 14.7 kDa protein in the cell wall, is a member of the PRP (proline-rich protein) family and has multiple functions, including resistance to low temperature and fungal infection. RNA gel blot analyses in the present work indicated that expression of EARLI1-like genes, EARLI1, At4G12470 and At4G12490, was down-regulated in Col-FRI-Sf2 RNAi plants derived from transformation with Agrobacterium strain ABI, which contains a construct encoding a double-strand RNA targeting 8CM of EARLI1. Phenotype analyses revealed that Col-FRI-Sf2 RNAi plants of EARLI1 flowered earlier than Col-FRI-Sf2 wild-type plants. The average bolting time of Col-FRI-Sf2 and Col-FRI-Sf2 RNAi plants was 39.7 and 19.4 days, respectively, under a long-day photoperiod. In addition, there were significant differences in main stem length, internode number and rosette leaf number between Col-FRI-Sf2 and Col-FRI-Sf2 RNAi plants. RT-PCR showed that EARLI1-like genes might delay flowering time through the autonomous and long-day photoperiod pathways by maintaining the abundance of FLC transcripts. In Col-FRI-Sf2 RNAi plants, transcription of FLC was repressed, while expression of SOC1 and FT was activated. Microscopy observations showed that EARLI1-like genes were also associated with morphogenesis of leaf cells in Arabidopsis. Using histochemical staining, EARLI1-like genes were found to be involved in regulation of lignin synthesis in inflorescence stems, and Col-FRI-Sf2 and Col-FRI-Sf2 RNAi plants had 9.67% and 8.76% dry weight lignin, respectively. Expression analysis revealed that cinnamoyl-CoA reductase, a key enzyme in lignin synthesis, was influenced by EARLI1-like genes. These data all suggest that EARLI1-like genes could control the flowering process and lignin synthesis in Arabidopsis. © 2011 German Botanical Society and The Royal Botanical Society of the Netherlands.

Analysis of Saccular Function With Vestibular Evoked Myogenic Potential Test in Meniere's Disease.

PubMed

Dabiri, Sasan; Yazdani, Nasrin; Esfahani, Mahdis; Tari, Niloufar; Adil, Susan; Mahvi, Zahra; Rezazadeh, Nima

2017-02-01

Meniere's disease is the disorder of inner ear characterized by vertigo, tinnitus and sensorineural hearing loss. The vestibular evoked myogenic potential (VEMP) test could be useful in the analysis of saccular function, and diagnosis of Meniere's disease. In this study, we've analyzed the saccular function, using VEMP test in different groups of Meniere's disease. Patients were categorized as possible, probable or definite Meniere's disease groups according to the guideline of American Academy of Otolaryngology-Head and Neck Surgery. The exclusion criteria were neuromuscular system diseases, diseases of central nervous system, inner ear disorders, conductive hearing loss, a history of ototoxic drug consumption, being a drug abuser and a positive history of inner ear surgery or manipulations. The VEMP test is the recording of positive and negative waves from sternocleidomastoid muscle that is made by an auditory click to the ear. From the total of 100 patients, the waves of VEMP test was seen in 59 patients which 19 patients had abnormal amplitude, and latency and 40 patients were with normally recorded waves. There was a significant relationship between the severity of hearing loss and a VEMP test without any recorded waves. Most of the cases with 'no wave recorded' VEMP test, were patients with severe hearing loss. However, there wasn't any relation between the pattern of hearing loss and 'no wave recorded' VEMP test. VEMP test could be a valuable diagnostic clue especially in patients with definite Meniere's disease.

Functional relevance of acoustic tracheal design in directional hearing in crickets.

PubMed

Schmidt, Arne K D; Römer, Heiner

2016-10-15

Internally coupled ears (ICEs) allow small animals to reliably determine the direction of a sound source. ICEs are found in a variety of taxa, but crickets have evolved the most complex arrangement of coupled ears: an acoustic tracheal system composed of a large cross-body trachea that connects two entry points for sound in the thorax with the leg trachea of both ears. The key structure that allows for the tuned directionality of the ear is a tracheal inflation (acoustic vesicle) in the midline of the cross-body trachea holding a thin membrane (septum). Crickets are known to display a wide variety of acoustic tracheal morphologies, most importantly with respect to the presence of a single or double acoustic vesicle. However, the functional relevance of this variation is still not known. In this study, we investigated the peripheral directionality of three co-occurring, closely related cricket species of the subfamily Gryllinae. No support could be found for the hypothesis that a double vesicle should be regarded as an evolutionary innovation to (1) increase interaural directional cues, (2) increase the selectivity of the directional filter or (3) provide a better match between directional and sensitivity tuning. Nonetheless, by manipulating the double acoustic vesicle in the rainforest cricket Paroecanthus podagrosus, selectively eliminating the sound-transmitting pathways, we revealed that these pathways contribute almost equally to the total amount of interaural intensity differences, emphasizing their functional relevance in the system. © 2016. Published by The Company of Biologists Ltd.

CCL11 elicits secretion of RNases from mouse eosinophils and their cell-free granules

PubMed Central

Shamri, Revital; Melo, Rossana C. N.; Young, Kristen M.; Bivas-Benita, Maytal; Xenakis, Jason J.; Spencer, Lisa A.; Weller, Peter F.

2012-01-01

Rapid secretion of eosinophil-associated RNases (EARs), such as the human eosinophilic cationic protein (ECP), from intracellular granules is central to the role of eosinophils in allergic diseases and host immunity. Our knowledge regarding allergic inflammation has advanced based on mouse experimental models. However, unlike human eosinophils, capacities of mouse eosinophils to secrete granule proteins have been controversial. To study mechanisms of mouse eosinophil secretion and EAR release, we combined an RNase assay of mouse EARs with ultrastructural studies. In vitro, mouse eosinophils stimulated with the chemokine eotaxin-1 (CCL11) secreted enzymatically active EARs (EC50 5 nM) by piecemeal degranulation. In vivo, in a mouse model of allergic airway inflammation, increased airway eosinophil infiltration (24-fold) correlated with secretion of active RNases (3-fold). Moreover, we found that eosinophilic inflammation in mice can involve eosinophil cytolysis and release of cell-free granules. Cell-free mouse eosinophil granules expressed functional CCR3 receptors and secreted their granule proteins, including EAR and eosinophil peroxidase in response to CCL11. Collectively, these data demonstrate chemokine-dependent secretion of EARs from both intact mouse eosinophils and their cell-free granules, findings pertinent to understanding the pathogenesis of eosinophil-associated diseases, in which EARs are key factors.—Shamri, R., Melo, R. C. N., Young, K. M., B.-B, M., Xenakis, J. J., Spencer, L. A., Weller, P. F. CCL11 elicits secretion of RNases from mouse eosinophils and their cell-free granules. PMID:22294786

Analysis of Eustachian Tube Dysfunction by Dynamic Slow Motion Video Endoscopy and Eustachian Tube Dysfunction Questionnaire in Chronic Otitis Media

PubMed Central

Han, Won Gue; Yoo, Jun; Rah, Yoon Chan; Chang, Jiwon; Im, Gi Jung; Song, Jae-Jun; Chae, Sung Won; Jung, Hak Hyun; Choi, June

2017-01-01

Objectives Eustachian tube dysfunction has been associated with most cases of middle-ear disease. We aimed to assess the effectiveness of dynamic slow motion video endoscopy (DSVE) as a test of eustachian tube dysfunction. Furthermore, we assessed the correlation of the test with the Valsalva maneuver, the seven-item Eustachian Tube Dysfunction Questionnaire (ETDQ-7), and intraoperative findings of the eustachian tube. Methods We retrospectively reviewed medical records from April to September 2014 to identify patients who were diagnosed with chronic otitis media (COM) at Korea University Ansan Hospital. They all underwent surgery because of COM without cholesteatoma and were assessed via the DSVE and ETDQ-7 to determine eustachian tube function. Results We reviewed 46 COM patients and examined 46 ears with COM and 46 ears on the contralateral side to COM that were thought to be normal. The mean DSVE grade in COM ears was 1.57±0.96, while the mean DSVE grade in contralateral ears was 1.15±0.94. The difference in DSVE between COM ears and normal ears was statistically significant (P=0.006). In the ETDQ-7, a higher score was related to intraoperative obstruction of the eustachian tube (P=0.012). Conclusion DSVE and ETDQ-7 can provide information regarding preoperative status of eustachian tube dysfunction by measuring dynamic structural changes of the eustachian tube in combination with other diagnostic tests. PMID:28602066

Adeno-associated virus-mediated gene delivery into the scala media of the normal and deafened adult mouse ear.

PubMed

Kilpatrick, L A; Li, Q; Yang, J; Goddard, J C; Fekete, D M; Lang, H

2011-06-01

Murine models are ideal for studying cochlear gene transfer, as many hearing loss-related mutations have been discovered and mapped within the mouse genome. However, because of the small size and delicate nature, the membranous labyrinth of the mouse is a challenging target for the delivery of viral vectors. To minimize injection trauma, we developed a procedure for the controlled release of adeno-associated viruses (AAVs) into the scala media of adult mice. This procedure poses minimal risk of injury to structures of the cochlea and middle ear, and allows for near-complete preservation of low and middle frequency hearing. In this study, transduction efficiency and cellular specificity of AAV vectors (serotypes 1, 2, 5, 6 and 8) were investigated in normal and drug-deafened ears. Using the cytomegalovirus promoter to drive gene expression, a variety of cell types were transduced successfully, including sensory hair cells and supporting cells, as well as cells in the auditory nerve and spiral ligament. Among all five serotypes, inner hair cells were the most effectively transduced cochlear cell type. All five serotypes of AAV vectors transduced cells of the auditory nerve, though serotype 8 was the most efficient vector for transduction. Our findings indicate that efficient AAV inoculation (via the scala media) can be performed in adult mouse ears, with hearing preservation a realistic goal. The procedure we describe may also have applications for intra-endolymphatic drug delivery in many mouse models of human deafness.

A new 3D finite element model of the IEC 60318-1 artificial ear: II. Experimental and numerical validation

NASA Astrophysics Data System (ADS)

Bravo, Agustín; Barham, Richard; Ruiz, Mariano; López, Juan Manuel; De Arcas, Guillermo; Alonso, Jesus

2012-12-01

In part I, the feasibility of using three-dimensional (3D) finite elements (FEs) to model the acoustic behaviour of the IEC 60318-1 artificial ear was studied and the numerical approach compared with classical lumped elements modelling. It was shown that by using a more complex acoustic model that took account of thermo-viscous effects, geometric shapes and dimensions, it was possible to develop a realistic model. This model then had clear advantages in comparison with the models based on equivalent circuits using lumped parameters. In fact results from FE modelling produce a better understanding about the physical phenomena produced inside ear simulator couplers, facilitating spatial and temporal visualization of the sound fields produced. The objective of this study (part II) is to extend the investigation by validating the numerical calculations against measurements on an ear simulator conforming to IEC 60318-1. For this purpose, an appropriate commercially available device is taken and a complete 3D FE model developed for it. The numerical model is based on key dimensional data obtained with a non-destructive x-ray inspection technique. Measurements of the acoustic transfer impedance have been carried out on the same device at a national measurement institute using the method embodied in IEC 60318-1. Having accounted for the actual device dimensions, the thermo-viscous effects inside narrow slots and holes and environmental conditions, the results of the numerical modelling were found to be in good agreement with the measured values.

Adeno-associated virus-mediated gene delivery into the scala media of the normal and deafened adult mouse ear

PubMed Central

Kilpatrick, Lauren A.; Li, Qian; Yang, John; Goddard, John C; Fekete, Donna M.; Lang, Hainan

2010-01-01

Murine models are ideal for studying cochlear gene transfer as many hearing loss-related mutations have been discovered and mapped within the mouse genome. However, due to its small size and delicate nature, the membranous labyrinth of the mouse is a challenging target for delivery of viral vectors. To minimize injection trauma, we developed a procedure for the controlled release of adeno-associated viruses (AAV) into the scala media of adult mice. This procedure poses minimal risk of injury to structures of the cochlea and middle ear and allows for near-complete preservation of low and middle frequency hearing. In the present study, transduction efficiency and cellular specificity of AAV vectors (serotypes 1, 2, 5, 6, and 8) were investigated in normal and drug-deafened ears. Using the cytomegalovirus (CMV) promoter to drive gene expression, a variety of cell types were transduced successfully, including sensory hair cells and supporting cells, as well as cells in the auditory nerve and spiral ligament. Among all five serotypes, inner hair cells (IHCs) were the most effectively transduced cochlear cell type. All five serotypes of AAV vectors transduced cells of the auditory nerve, though serotype 8 was the most efficient vector for transduction. Our findings indicate that efficient AAV inoculation (via the scala media) can be performed in adult mouse ears, with hearing preservation a realistic goal. The procedure we describe may also have applications for intra-endolymphatic drug delivery in many mouse models of human deafness. PMID:21209625

Theoretical investigation of the force and dynamically coupled torsional-axial-lateral dynamic response of eared rotors

NASA Technical Reports Server (NTRS)

David, J. W.; Mitchell, L. D.

1982-01-01

Difficulties in solution methodology to be used to deal with the potentially higher nonlinear rotor equations when dynamic coupling is included. A solution methodology is selected to solve the nonlinear differential equations. The selected method was verified to give good results even at large nonlinearity levels. The transfer matrix methodology is extended to the solution of nonlinear problems.

"Tjaa, I Do Have Ears, but I Do Not Hear": New Literacy Studies and the Awakening of a Hearing Teacher

ERIC Educational Resources Information Center

Gísladóttir, Karen Rut

2014-01-01

To address the low literacy achievement of minority students, the sociocultural movement of the New Literacy Studies (NLS) encourages us to expand on current understandings of literacy. Instead of thinking of literacy as a neutral set of skills transferable from one setting to another, NLS researchers encourage us to contextualize literacy within…

[Establishment of fibroblast cell line and its biological characteristics in Matou goat].

PubMed

Li, Tianda; Liu, Chousheng; Wang, Zhigang; Zhang, Liping; Sun, Xiuzhu; Zhao, Junjin; Meng, Fei; Luo, Guihe; Zhu, Jinqing

2008-12-01

Taking Matou goat ear margin as the study material, we succeeded in established a fibroblast cell line by the method of explant culture directly. Observations on morphology, dynamic growth, determination of viability, analysis of karyotype, test of microorganism and other characteristics were detected. Results showed: Population Doubling Time (PDT) of cells was approximately 36 h; Cell viability was 96.7% after thawing; The status of cell After passage was constant; Analysis of chromosomal karyotyps indicated that diploid (2n=60) account for 98% in the cell line. Every index in the cell line met all the standard quality controls of ATCC in USA. The established of Matou goat ear fibroblast cell line has not only important genetic resources preserved at the cell level, but also valuable material for genome, postgenome and somatic cell nuclear transfer research.

Perspectives for the treatment of sensorineural hearing loss by cellular regeneration of the inner ear.

PubMed

Almeida-Branco, Mario S; Cabrera, Sonia; Lopez-Escamez, Jose A

2015-01-01

Sensorineural hearing loss is a caused by the loss of the cochlear hair cells with the consequent deafferentation of spiral ganglion neurons. Humans do not show endogenous cellular regeneration in the inner ear and there is no exogenous therapy that allows the replacement of the damaged hair cells. Currently, treatment is based on the use of hearing aids and cochlear implants that present different outcomes, some difficulties in auditory discrimination and a limited useful life. More advanced technology is hindered by the functional capacity of the remaining spiral ganglion neurons. The latest advances with stem cell therapy and cellular reprogramming have developed several possibilities to induce endogenous regeneration or stem cell transplantation to replace damaged inner ear hair cells and restore hearing function. With further knowledge of the cellular and molecular biology of the inner ear and its embryonic development, it will be possible to use induced stem cells as in vitro models of disease and as replacement cellular therapy. Investigation in this area is focused on generating cellular therapy with clinical use for the treatment of profound sensorineural hearing loss. Copyright © 2014 Elsevier España, S.L.U. and Sociedad Española de Otorrinolaringología y Patología Cérvico-Facial. All rights reserved.

Training to use voice onset time as a cue to talker identification induces a left-ear/right-hemisphere processing advantage.

PubMed

Francis, Alexander L; Driscoll, Courtney

2006-09-01

We examined the effect of perceptual training on a well-established hemispheric asymmetry in speech processing. Eighteen listeners were trained to use a within-category difference in voice onset time (VOT) to cue talker identity. Successful learners (n=8) showed faster response times for stimuli presented only to the left ear than for those presented only to the right. The development of a left-ear/right-hemisphere advantage for processing a prototypically phonetic cue supports a model of speech perception in which lateralization is driven by functional demands (talker identification vs. phonetic categorization) rather than by acoustic stimulus properties alone.

The value of frozen cartilage tissues without cryoprotection for genetic conservation.

PubMed

Cetinkaya, Gaye; Hatipoglu, Ibrahim; Arat, Sezen

2014-02-01

Animal tissues frozen without cryoprotection are thought to be inappropriate for use as a donor for somatic cell nuclear transfer (SCNT) studies. Cells in tissues that have been frozen without a cryoprotectant are commonly thought to be dead or to have lost genomic integrity. However, in this study we show that the frozen auricular cartilage tissues of anatolian buffalo contain a considerable number of viable healthy cells. The cells in auricular cartilage tissues are resistant to cryo-injury at -80°C. Primary cell cultures were established from defrosted ear tissues which were frozen without cryoprotectant. The growth and functional characteristics of primary cell cultures are characterized according to cell growth curve, cell cycle analysis, karyotype and GAG synthesis. The results indicate that frozen cartilage tissues could be valuable materials for the conservation of species and SCNT technology. Copyright © 2013 Elsevier Inc. All rights reserved.

A comparison of aphasic and non-brain-injured adults on a dichotic CV-syllable listening task.

PubMed

Shanks, J; Ryan, W

1976-06-01

A dichotic CV-syllable listening task was administered to a group of eleven non-brain-injured adults and to a group of eleven adult aphasics. The results of this study may be summarized as follows: 1)The group of non-brain-injured adults showed a slight right ear advantage for dichotically presented CV-syllables. 2)In comparison with the control group the asphasic group showed a bilateral deficit in response to the dichotic CV-syllables, superimposed on a non-significant right ear advantage. 3) The asphasic group demonstrated a great deal of intersubject variability on the dichotic task with six aphasics showing a right ear preference for the stimuli. The non-brain-injured subjects performed more homogeneously on the task. 4) The two subgroups of aphasics, a right ear advantage group and a left ear advantage group, performed significantly different on the dichotic listening task. 5) Single correct data analysis proved valuable by deleting accuracy of report for an examination of trials in which there was true competition for the single left hemispheric speech processor. These results were analyzed in terms of a functional model of auditory processing. In view of this model, the bilateral deficit in dichotic performance of the asphasic group was accounted for by the presence of a lesion within the dominant left hemisphere, where the speech signals from both ears converge for final processing. The right ear advantage shown by one asphasic subgroup was explained by a lesion interfering with the corpus callosal pathways from the left hemisphere; the left ear advantage observed within the other subgroup was explained by a lesion in the area of the auditory processor of the left hemisphere.

Estimation of sex from the anthropometric ear measurements of a Sudanese population.

PubMed

Ahmed, Altayeb Abdalla; Omer, Nosyba

2015-09-01

The external ear and its prints have multifaceted roles in medico-legal practice, e.g., identification and facial reconstruction. Furthermore, its norms are essential in the diagnosis of congenital anomalies and the design of hearing aids. Body part dimensions vary in different ethnic groups, so the most accurate statistical estimations of biological attributes are developed using population-specific standards. Sudan lacks comprehensive data about ear norms; moreover, there is a universal rarity in assessing the possibility of sex estimation from ear dimensions using robust statistical techniques. Therefore, this study attempts to establish data for normal adult Sudanese Arabs, assessing the existence of asymmetry and developing a population-specific equation for sex estimation. The study sample comprised 200 healthy Sudanese Arab volunteers (100 males and 100 females) in the age range of 18-30years. The physiognomic ear length and width, lobule length and width, and conchal length and width measurements were obtained by direct anthropometry, using a digital sliding caliper. Moreover, indices and asymmetry were assessed. Data were analyzed using basic descriptive statistics and discriminant function analyses employing jackknife validations of classification results. All linear dimensions used were sexually dimorphic except lobular lengths. Some of the variables and indices show asymmetry. Ear dimensions showed cross-validated sex classification accuracy ranging between 60.5% and 72%. Hence, the ear measurements cannot be used as an effective tool in the estimation of sex. However, in the absence of other more reliable means, it still can be considered a supportive trait in sex estimation. Further, asymmetry should be considered in identification from the ear measurements. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

Right Ear Advantage of Speech Audiometry in Single-sided Deafness.

PubMed

Wettstein, Vincent G; Probst, Rudolf

2018-04-01

Postlingual single-sided deafness (SSD) is defined as normal hearing in one ear and severely impaired hearing in the other ear. A right ear advantage and dominance of the left hemisphere are well established findings in individuals with normal hearing and speech processing. Therefore, it seems plausible that a right ear advantage would exist in patients with SSD. The audiometric database was searched to identify patients with SSD. Results from the German monosyllabic Freiburg word test and four-syllabic number test in quiet were evaluated. Results of right-sided SSD were compared with left-sided SSD. Statistical calculations were done with the Mann-Whitney U test. Four hundred and six patients with SSD were identified, 182 with right-sided and 224 with left-sided SSD. The two groups had similar pure-tone thresholds without significant differences. All test parameters of speech audiometry had better values for right ears (SSD left) when compared with left ears (SSD right). Statistically significant results (p < 0.05) were found for a weighted score (social index, 98.2 ± 4% right and 97.5 ± 4.7% left, p < 0.026), for word understanding at 60 dB SPL (95.2 ± 8.7% right and 93.9 ± 9.1% left, p < 0.035), and for the level at which 100% understanding was reached (61.5 ± 10.1 dB SPL right and 63.8 ± 11.1 dB SPL left, p < 0.022) on a performance-level function. A right ear advantage of speech audiometry was found in patients with SSD in this retrospective study of audiometric test results.

Determinants of Change in Air-Bone Gap and Bone Conduction in Patients Operated on for Chronic Otitis Media.

PubMed

Wiatr, Maciej; Wiatr, Agnieszka; Składzień, Jacek; Stręk, Paweł

2015-08-11

Middle ear surgery aims to eliminate pathology from the middle ear, improve drainage and ventilation of the postoperative cavity, and reconstruct the tympanic membrane and ossicles. The aim of this work is to define the factors that affect ABG (air-bone gap) and bone conduction in the patients operated on due to chronic otitis media. A prospective analysis of patients operated on due to diseases of the middle ear during 2009-2012 was carried out. The cases of patients operated on for the first time due to chronic otitis media were analyzed. The analysis encompassed patients who had undergone middle ear surgery. The patients were divided into several groups taking into account the abnormalities of the middle ear mucous and damage of the ossicular chain observed during otosurgery. A significant hearing improvement was observed in patients with type 2 tympanoplasty in the course of chronic cholesteatoma otitis media and in patients with simple chronic inflammatory process in whom a PORP was used in the reconstruction. Granulation tissue was an unfavorable factor of hearing improvement following tympanoplasty. A significant improvement of bone conduction was observed in the patients with dry perforation without other lesions in the middle ear. The elimination of granulation lesions was a positive factor for the future improvement of the function of the inner ear. The presence of granuloma-related lesions in the middle ear spaces is likely to impede hearing improvement. Damage to the ossicular chain rules out the possibility of bone conduction improvement after surgery. The prognosis on tube-related simple chronic otitis media after myringoplasty, with the preserved continuity of the ossicular chain, consists of closing the ABG and leads to significant improvement of bone conduction.

Tuboimpedance: A New Test of Eustachian Tube Function.

PubMed

Smith, Matthew E; Zou, Charlie C; Blythe, Andrew J C; Tysome, James R

2017-04-01

Objective Eustachian tube (ET) dysfunction is most frequently caused by a failure of the ET to adequately open; however, there is currently no reliable method of assessing this. Tubomanometry has recently shown good interindividual repeatability as a measure of ET function by measuring middle ear pressure after the application of regulated nasopharyngeal pressures during swallowing. We present the first reports of a novel test: middle ear impedance measurements during standard nasopharyngeal pressure application (tuboimpedance). We assess repeatability in healthy ears and any advantages over tubomanometry. Study Design Exploratory cohort diagnosis study. Setting Tertiary referral center. Subjects Twenty screened, healthy ears (10 volunteers). Methods Tubomanometry and tuboimpedance tests were performed while individuals swallowed with applied nasopharyngeal pressures of 20, 30, 40, and 50 mbar. Eustachian tube opening detection rate and test repeatability (measured by intraclass correlation coefficient [ICC]) for immediate and delayed repeats at each pressure were compared. Results ET opening was detected more frequently using tuboimpedance, with a 100% detection rate using a nasopharyngeal pressure of 30 mbar or more, compared to 88% to 96% with tubomanometry. Detection of ET opening at 20 mbar was possible with tuboimpedance. Repeatability of both tests was mostly strong (ICC >0.7) for both immediate and delayed repeats. Repeatability for the tubomanometry R value was only fair to moderate. Conclusion Tuboimpedance may provide a repeatable measure of ET opening that is easier to perform due to lower nasopharyngeal pressures required and fewer issues with poor ear-probe sealing. Further assessment in patients with different forms of ET dysfunction is required.

Preservation of vestibular function after scala vestibuli cochlear implantation.

PubMed

Suzuki, Mitsuya; Goto, Takio; Kashio, Akinori; Yasui, Takuya; Sakamoto, Takashi; Ito, Ken; Yamasoba, Tatsuya

2011-10-01

A 58-year-old man, in whom the cochlear implant (CI) had been inserted into the left ear, had right middle-ear cancer. The CI was removed immediately before receiving subtotal removal of right temporal bone. Four months later, the CI was again inserted in his left cochlea. Because of obliterated scala tympani, the 22 active electrodes of the CI were placed into the scala vestibuli. After the surgery, the patient complained that he experienced rotary vertigo and "jumbling of vertical direction" of objects on walking. Using rotation test, we evaluated vestibular function of remaining left ear. Numerous horizontal nystagmus beats were induced during earth-vertical axis rotation, whereas vertical downbeat nystagmus was scarcely induced during off-vertical axis rotation. The horizontal vestibulo-ocular reflex (VOR) was almost normally induced by sinusoidal stimulation at 0.8Hz. These data suggest that the scala vestibuli insertion of CI would be not so invasive against the lateral semicircular canal. Copyright © 2011 Elsevier Ireland Ltd. All rights reserved.

Estimation of the EEG power spectrum using MRI T(2) relaxation time in traumatic brain injury.

PubMed

Thatcher, R W; Biver, C; Gomez, J F; North, D; Curtin, R; Walker, R A; Salazar, A

2001-09-01

To study the relationship between magnetic resonance imaging (MRI) T(2) relaxation time and the power spectrum of the electroencephalogram (EEG) in long-term follow up of traumatic brain injury. Nineteen channel quantitative electroencephalograms or qEEG, tests of cognitive function and quantitative MRI T(2) relaxation times (qMRI) were measured in 18 mild to severe closed head injured outpatients 2 months to 4.6 years after injury and 11 normal controls. MRI T(2) and the Laplacian of T(2) were then correlated with the power spectrum of the scalp electrical potentials and current source densities of the qEEG. qEEG and qMRI T(2) were related by a frequency tuning with maxima in the alpha (8-12Hz) and the lower EEG frequencies (0.5-5Hz), which varied as a function of spatial location. The Laplacian of T(2) acted like a spatial-temporal "lens" by increasing the spatial-temporal resolution of correlation between 3-dimensional T(2) and the ear referenced alert but resting spontaneous qEEG. The severity of traumatic brain injury can be modeled by a linear transfer function that relates the molecular qMRI to qEEG resonant frequencies.

A long-term high-fat diet increases oxidative stress, mitochondrial damage and apoptosis in the inner ear of D-galactose-induced aging rats.

PubMed

Du, Zhengde; Yang, Yang; Hu, Yujuan; Sun, Yu; Zhang, Sulin; Peng, Wei; Zhong, Yi; Huang, Xiang; Kong, Weijia

2012-05-01

In humans, chronic dyslipidemia associated with elevated triglycerides may reduce auditory function. However, there is little evidence available in the literature concerning the effects of a long-term high-fat diet (HFD) on the inner ears of animals. The purpose of this study was to investigate the effect of 12 month-HFD on the inner ear of Sprague-Dawley rats and on the D-galactose (D-gal)-induced aging process in the inner ear. We found that 12 month-HFD markedly elevated the auditory brainstem response (ABR) threshold in the high-frequency region. The HFD significantly increased the generation of reactive oxygen species (ROS) and the expressions of NADPH oxidase (NOX) and the uncoupling proteins (UCP). Furthermore, an elevated accumulation of the mitochondrial DNA (mtDNA) common deletion (CD) and mitochondrial ultrastructural changes in the inner ear suggested that there was mitochondrial damage in response to the excessive fat intake. The expression level of cleaved caspase-3 and the number of terminal deoxynucleotidyl transferase (TdT)-mediated deoxyuridine triphosphate (dUTP) nick-end-labelling (TUNEL)-positive cells in the inner ear were increased by the HFD. The effects of D-gal on the inner ears were similar with 12 month-HFD. We found that rats receiving both the HFD and D-gal exhibited a greater shift in the ABR threshold, larger increases in the expression levels of NOX, UCP and cleaved caspase-3 and an increased number of TUNEL-positive cells in the inner ear. The present study demonstrated that HFD may induce oxidative stress, mitochondrial damage and apoptosis in the inner ear, and it provided evidence regarding the link between HFD and an increased risk of age-related hearing loss. Copyright © 2012 Elsevier B.V. All rights reserved.

Comparison of the benefits of cochlear implantation versus contra-lateral routing of signal hearing aids in adult patients with single-sided deafness: study protocol for a prospective within-subject longitudinal trial.

PubMed

Kitterick, Pádraig T; O'Donoghue, Gerard M; Edmondson-Jones, Mark; Marshall, Andrew; Jeffs, Ellen; Craddock, Louise; Riley, Alison; Green, Kevin; O'Driscoll, Martin; Jiang, Dan; Nunn, Terry; Saeed, Shakeel; Aleksy, Wanda; Seeber, Bernhard U

2014-01-01

Individuals with a unilateral severe-to-profound hearing loss, or single-sided deafness, report difficulty with listening in many everyday situations despite having access to well-preserved acoustic hearing in one ear. The standard of care for single-sided deafness available on the UK National Health Service is a contra-lateral routing of signals hearing aid which transfers sounds from the impaired ear to the non-impaired ear. This hearing aid has been found to improve speech understanding in noise when the signal-to-noise ratio is more favourable at the impaired ear than the non-impaired ear. However, the indiscriminate routing of signals to a single ear can have detrimental effects when interfering sounds are located on the side of the impaired ear. Recent published evidence has suggested that cochlear implantation in individuals with a single-sided deafness can restore access to the binaural cues which underpin the ability to localise sounds and segregate speech from other interfering sounds. The current trial was designed to assess the efficacy of cochlear implantation compared to a contra-lateral routing of signals hearing aid in restoring binaural hearing in adults with acquired single-sided deafness. Patients are assessed at baseline and after receiving a contra-lateral routing of signals hearing aid. A cochlear implant is then provided to those patients who do not receive sufficient benefit from the hearing aid. This within-subject longitudinal design reflects the expected care pathway should cochlear implantation be provided for single-sided deafness on the UK National Health Service. The primary endpoints are measures of binaural hearing at baseline, after provision of a contra-lateral routing of signals hearing aid, and after cochlear implantation. Binaural hearing is assessed in terms of the accuracy with which sounds are localised and speech is perceived in background noise. The trial is also designed to measure the impact of the interventions on hearing- and health-related quality of life. This multi-centre trial was designed to provide evidence for the efficacy of cochlear implantation compared to the contra-lateral routing of signals. A purpose-built sound presentation system and established measurement techniques will provide reliable and precise measures of binaural hearing. Current Controlled Trials http://www.controlled-trials.com/ISRCTN33301739 (05/JUL/2013).

Big Stimulus, Little Ears: Safety in Administering Vestibular Evoked Myogenic Potentials (VEMP) in Children

PubMed Central

Thomas, Megan L.A.; Fitzpatrick, Denis; McCreery, Ryan; Janky, Kristen L.

2017-01-01

Background Cervical and ocular Vestibular Evoked Myogenic Potentials (VEMPs) have become common clinical vestibular assessments. However, VEMP testing requires high intensity stimuli, raising concerns regarding safety with children, where sound pressure levels may be higher due to their smaller ear canal volumes. Purpose The purpose of this study was to estimate the range of peak-to-peak equivalent sound pressure levels (peSPLs) in child and adult ears in response to high intensity stimuli (i.e., 100 dB normal hearing level (nHL)) commonly used for VEMP testing and make a determination of whether acoustic stimuli levels with VEMP testing are safe for use in children. Research Design Prospective Experimental. Study Sample Ten children (4–6 years) and ten young adults (24 – 35 years) with normal hearing sensitivity and middle ear function participated in the study. Data Collection and Analysis Probe microphone peSPL measurements of clicks and 500 Hz tonebursts (TBs) were recorded in tubes of small, medium, and large diameter, and in a Brüel & Kjær Ear Simulator Type 4157 to assess for linearity of the stimulus at high levels. The different diameter tubes were used to approximate the range of cross-sectional areas in infant, child, and adult ears, respectively. Equivalent ear canal volume and peSPL measurements were then recorded in child and adult ears. Lower intensity levels were used in the participant’s ears to limit exposure to high intensity sound. The peSPL measurements in participant ears were extrapolated using predictions from linear mixed models to determine if equivalent ear canal volume significantly contributed to overall peSPL and to estimate the mean and 95% confidence intervals of peSPLs in child and adult ears when high intensity stimulus levels (100 dB nHL) are used for VEMP testing without exposing subjects to high-intensity stimuli. Results Measurements from the coupler and tubes suggested: 1) each stimuli was linear, 2) there were no distortions or non-linearities at high levels, and 3) peSPL increased with decreased tube diameter. Measurements in participant ears suggested: 1) peSPL was approximately 3 dB larger in child compared to adult ears, and 2) peSPL was larger in response to clicks compared to 500 Hz TBs. The model predicted the following 95% confidence interval for a 100 dB nHL click: 127–136.5 dB peSPL in adult ears and 128.7–138.2 dB peSPL in child ears. The model predicted the following 95% confidence interval for a 100 dB nHL 500 Hz TB stimulus: 122.2 – 128.2 dB peSPL in adult ears and 124.8–130.8 dB peSPL in child ears. Conclusions Our findings suggest that 1) when completing VEMP testing, the stimulus is approximately 3 dB higher in a child’s ear, 2) a 500 Hz TB is recommended over a click as it has lower peSPL compared to the click, and 3) both duration and intensity should be considered when choosing VEMP stimuli. Calculating the total sound energy exposure for your chosen stimuli is recommended as it accounts for both duration and intensity. When using this calculation for children, consider adding 3 dB to the stimulus level. PMID:28534730

Big Stimulus, Little Ears: Safety in Administering Vestibular-Evoked Myogenic Potentials in Children.

PubMed

Thomas, Megan L A; Fitzpatrick, Denis; McCreery, Ryan; Janky, Kristen L

2017-05-01

Cervical and ocular vestibular-evoked myogenic potentials (VEMPs) have become common clinical vestibular assessments. However, VEMP testing requires high intensity stimuli, raising concerns regarding safety with children, where sound pressure levels may be higher due to their smaller ear canal volumes. The purpose of this study was to estimate the range of peak-to-peak equivalent sound pressure levels (peSPLs) in child and adult ears in response to high intensity stimuli (i.e., 100 dB normal hearing level [nHL]) commonly used for VEMP testing and make a determination of whether acoustic stimuli levels with VEMP testing are safe for use in children. Prospective experimental. Ten children (4-6 years) and ten young adults (24-35 years) with normal hearing sensitivity and middle ear function participated in the study. Probe microphone peSPL measurements of clicks and 500 Hz tonebursts (TBs) were recorded in tubes of small, medium, and large diameter, and in a Brüel & Kjær Ear Simulator Type 4157 to assess for linearity of the stimulus at high levels. The different diameter tubes were used to approximate the range of cross-sectional areas in infant, child, and adult ears, respectively. Equivalent ear canal volume and peSPL measurements were then recorded in child and adult ears. Lower intensity levels were used in the participant's ears to limit exposure to high intensity sound. The peSPL measurements in participant ears were extrapolated using predictions from linear mixed models to determine if equivalent ear canal volume significantly contributed to overall peSPL and to estimate the mean and 95% confidence intervals of peSPLs in child and adult ears when high intensity stimulus levels (100 dB nHL) are used for VEMP testing without exposing subjects to high-intensity stimuli. Measurements from the coupler and tubes suggested: 1) each stimuli was linear, 2) there were no distortions or nonlinearities at high levels, and 3) peSPL increased with decreased tube diameter. Measurements in participant ears suggested: 1) peSPL was approximately 3 dB larger in child compared to adult ears, and 2) peSPL was larger in response to clicks compared to 500 Hz TBs. The model predicted the following 95% confidence interval for a 100 dB nHL click: 127-136.5 dB peSPL in adult ears and 128.7-138.2 dB peSPL in child ears. The model predicted the following 95% confidence interval for a 100 dB nHL 500 Hz TB stimulus: 122.2-128.2 dB peSPL in adult ears and 124.8-130.8 dB peSPL in child ears. Our findings suggest that 1) when completing VEMP testing, the stimulus is approximately 3 dB higher in a child's ear, 2) a 500 Hz TB is recommended over a click as it has lower peSPL compared to the click, and 3) both duration and intensity should be considered when choosing VEMP stimuli. Calculating the total sound energy exposure for your chosen stimuli is recommended as it accounts for both duration and intensity. When using this calculation for children, consider adding 3 dB to the stimulus level. American Academy of Audiology

Overlapping and distinct pRb pathways in the mammalian auditory and vestibular organs

PubMed Central

Huang, Mingqian; Sage, Cyrille; Tang, Yong; Lee, Sang Goo; Petrillo, Marco; Hinds, Philip W

2011-01-01

Retinoblastoma gene (Rb1) is required for proper cell cycle exit in the developing mouse inner ear and its deletion in the embryo leads to proliferation of sensory progenitor cells that differentiate into hair cells and supporting cells. In a conditional hair cell Rb1 knockout mouse, Pou4f3-Cre-pRb™/™, pRb™/™ utricular hair cells differentiate and survive into adulthood whereas differentiation and survival of pRb™/™ cochlear hair cells are impaired. To comprehensively survey the pRb pathway in the mammalian inner ear, we performed microarray analysis of pRb™/™ cochlea and utricle. The comparative analysis shows that the core pathway shared between pRb™/™ cochlea and utricle is centered on e2F, the key pathway that mediates pRb function. A majority of differentially expressed genes and enriched pathways are not shared but uniquely associated with pRb™/™ cochlea or utricle. In pRb™/™ cochlea, pathways involved in early inner ear development such as Wnt/β-catenin and Notch were enriched, whereas pathways involved in proliferation and survival are enriched in pRb™/™ utricle. Clustering analysis showed that the pRb™/™ inner ear has characteristics of a younger control inner ear, an indication of delayed differentiation. We created a transgenic mouse model (ER-Cre-pRbflox/flox) in which Rb1 can be acutely deleted postnatally. Acute Rb1 deletion in the adult mouse fails to induce proliferation or cell death in inner ear, strongly indicating that Rb1 loss in these postmitotic tissues can be effectively compensated for, or that pRb-mediated changes in the postmitotic compartment result in events that are functionally irreversible once enacted. This study thus supports the concept that pRb-regulated pathways relevant to hair cell development, encompassing proliferation, differentiation and survival, act predominantly during early development. PMID:21239885

Demonstration of extrapulmonary activity of angiotensin converting enzyme in intact tissue preparations.

PubMed

Lembeck, F; Griesbacher, T; Eckhardt, M

1990-05-01

1. The activity of angiotensin converting enzyme (ACE) has been studied on functional parameters of intact isolated preparations of extrapulmonary tissues. The conversion of angiotensin I (A I) to angiotensin II (A II) and the cleavage of bradykinin (BK) were used as indicators of ACE activity. Captopril was employed as a specific inhibitor of ACE. 2. Captopril augmented the BK-induced contractions of the rat isolated uterus, the BK- and substance P-induced contractions of the guinea-pig ileum, and the BK-induced venoconstriction in the isolated perfused ear of the rabbit. Degradation of BK by ACE was calculated to be 52% in the rat uterus and 75% in the rabbit perfused ear. 3. Captopril inhibited the A I-induced contractions of the rat isolated colon, the A I-induced vasoconstriction in the isolated perfused ear of the rabbit and the rise in blood pressure induced by i.a. injections of A I in pithed rats. Conversion of A I to A II was calculated to be 13% in the rat colon and 26% in the rabbit perfused ear. 4. From estimations of the A II activity (bioassay on the rat colon) in the effluent of the perfused ear of the rabbit after injections of A I into the arterial inflow cannula it was calculated that approximately one tenth of A I was converted to A II during a single passage through the ear (less than 15 s). 5. The present experiments suggest that the high activity of ACE in endothelium of blood vessels of extrapulmonary tissues may provide an additional (endothelium-dependent) local vasoconstrictor mechanism by the rapid formation of A II and inactivation of BK. The ACE activity in non-vascular smooth muscles, other than those of blood vessels, may also affect the physiological functions of these tissues.

Scala vestibuli pressure and three-dimensional stapes velocity measured in direct succession in gerbil.

PubMed

Decraemer, W F; de La Rochefoucauld, O; Dong, W; Khanna, S M; Dirckx, J J J; Olson, E S

2007-05-01

It was shown that the mode of vibration of the stapes has a predominant piston component but rotations producing tilt of the footplate are also present. Tilt and piston components vary with frequency. Separately it was shown that the pressure gain between ear canal and scala vestibuli was a remarkably flat and smooth function of frequency. Is tilt functional contributing to the pressure in the scala vestibuli and helping in smoothing the pressure gain? In experiments on gerbil the pressure in the scala vestibuli directly behind the footplate was measured while recording simultaneously the pressure produced by the sound source in the ear canal. Successively the three-dimensional motion of the stapes was measured in the same animal. Combining the vibration measurements with an anatomical shape measurement from a micro-CT (CT: computed tomography) scan the piston-like motion and the tilt of the footplate was calculated and correlated to the corresponding scala vestibuli pressure curves. No evidence was found for the hypothesis that dips in the piston velocity are filled by peaks in tilt in a systematic way to produce a smooth middle ear pressure gain function. The present data allowed calculations of the individual cochlear input impedances.

The MOC reflex during active listening to speech.

PubMed

Garinis, Angela C; Glattke, Theodore; Cone, Barbara K

2011-10-01

The purpose of this study was to test the hypothesis that active listening to speech would increase medial olivocochlear (MOC) efferent activity for the right vs. the left ear. Click-evoked otoacoustic emissions (CEOAEs) were evoked by 60-dB p.e. SPL clicks in 13 normally hearing adults in 4 test conditions for each ear: (a) in quiet; (b) with 60-dB SPL contralateral broadband noise; (c) with words embedded (at -3-dB signal-to-noise ratio [SNR]) in 60-dB SPL contralateral noise during which listeners directed attention to the words; and (d) for the same SNR as in the 3rd condition, with words played backwards. There was greater suppression during active listening compared with passive listening that was apparent in the latency range of 6- to 18-ms poststimulus onset. Ear differences in CEOAE amplitude were observed in all conditions, with right-ear amplitudes larger than those for the left. The absolute difference between CEOAE amplitude in quiet and with contralateral noise, a metric of suppression, was equivalent for right and left ears. When the amplitude differences were normalized, suppression was greater for noise presented to the right and the effect measured for a probe in the left ear. The findings support the theory that cortical mechanisms involved in listening to speech affect cochlear function through the MOC efferent system.

Mastoiditis and facial paralysis as initial manifestations of temporal bone systemic diseases - the significance of the histopathological examination.

PubMed

Maniu, Alma Aurelia; Harabagiu, Oana; Damian, Laura Otilia; Ştefănescu, Eugen HoraŢiu; FănuŢă, Bogdan Marius; Cătană, Andreea; Mogoantă, Carmen Aurelia

2016-01-01

Several systemic diseases, including granulomatous and infectious processes, tumors, bone disorders, collagen-vascular and other autoimmune diseases may involve the middle ear and temporal bone. These diseases are difficult to diagnose when symptoms mimic acute otomastoiditis. The present report describes our experience with three such cases initially misdiagnosed. Their predominating symptoms were otological with mastoiditis, hearing loss, and subsequently facial nerve palsy. The cases were considered an emergency and the patients underwent tympanomastoidectomy, under the suspicion of otitis media with cholesteatoma, in order to remove a possible abscess and to decompress the facial nerve. The common features were the presence of severe granulation tissue filling the mastoid cavity and middle ear during surgery, without cholesteatoma. The definitive diagnoses was made by means of biopsy of the granulation tissue from the middle ear, revealing granulomatosis with polyangiitis (formerly known as Wegener's granulomatosis) in one case, middle ear tuberculosis and diffuse large B-cell lymphoma respectively. After specific associated therapy facial nerve functions improved, and atypical inflammatory states of the ear resolved. As a group, systemic diseases of the middle ear and temporal bone are uncommon, but aggressive lesions. After analyzing these cases and reviewing the literature, we would like to stress upon the importance of microscopic examination of the affected tissue, required for an accurate diagnosis and effective treatment.

Dichotic listening during forced-attention in a patient with left hemispherectomy.

PubMed

Wester, K; Hugdahl, K; Asbjørnsen, A

1991-02-01

A young left-handed girl with an extensive posttraumatic lesion in the left hemisphere was tested with dichotic listening (DL) under three different attentional instructions. The major aim of the study was to evaluate a structural vs attentional explanation for dichotic listening. As both her expressive and receptive language functions were intact after the lesion, it was assumed that the right hemisphere was the language-dominant one. In the free-report condition, she was free to divert attention to and to report from both ear inputs. In the forced-right condition, she was instructed to attend to and report only from the right ear input. In the forced-left condition, she was instructed to attend to and to report only from the left-ear input. Her performance was compared with data from a previously collected sample of normal left-handed females. Analysis showed that the patient, in contrast to the normal sample, revealed a complete right-ear extinction phenomenon, irrespective of attentional instruction. Furthermore, she showed superior correct reports from the left ear, compared with those of the normal sample, also irrespective of attentional instruction. It is concluded that these results support a structural, rather than attentional explanation for the right-ear advantage (REA) typically observed in dichotic listening. The utility of validating the dichotic listening technique on patients with brain lesions is discussed.

Not All Inner Ears are the Same: Otolith Matrix Proteins in the Inner Ear of Sub-Adult Cichlid Fish, Oreochromis Mossambicus, Reveal Insights Into the Biomineralization Process.

PubMed

Weigele, Jochen; Franz-Odendaal, Tamara A; Hilbig, Reinhard

2016-02-01

The fish ear stones (otoliths) consist mainly of calcium carbonate and have lower amounts of a proteinous matrix. This matrix consists of macromolecules, which directly control the biomineralization process. We analyzed the composition of this proteinous matrix by mass spectrometry in a shotgun approach. For this purpose, an enhanced protein purification technique was developed that excludes any potential contamination of proteins from body fluids. Using this method we identified eight proteins in the inner ear of Oreochromis mossambicus. These include the common otolith matrix proteins (OMP-1, otolin-1, neuroserpin, SPARC and otoconin), and three proteins (alpha tectorin, otogelin and transferrin) not previously localized to the otoliths. Moreover, we were able to exclude the occurrence of two matrix proteins (starmaker and pre-cerebellin-like protein) known from other fish species. In further analyses, we show that the absence of the OMP starmaker corresponds to calcitic otoliths and that pre-cerebellin-like protein is not present at any stage during the development of the otoliths of the inner ear. This study shows O. mossambicus does not have all of the known otolith proteins indicating that the matrix proteins in the inner ear of fish are not the same across species. Further functional studies of the novel proteins we identified during otolith development are required. © 2015 Wiley Periodicals, Inc.

Dichotic listening performance predicts language comprehension.

PubMed

Asbjørnsen, Arve E; Helland, Turid

2006-05-01

Dichotic listening performance is considered a reliable and valid procedure for the assessment of language lateralisation in the brain. However, the documentation of a relationship between language functions and dichotic listening performance is sparse, although it is accepted that dichotic listening measures language perception. In particular, language comprehension should show close correspondence to perception of language stimuli. In the present study, we tested samples of reading-impaired and normally achieving children between 10 and 13 years of age with tests of reading skills, language comprehension, and dichotic listening to consonant-vowel (CV) syllables. A high correlation between the language scores and the dichotic listening performance was expected. However, since the left ear score is believed to be an error when assessing language laterality, covariation was expected for the right ear scores only. In addition, directing attention to one ear input was believed to reduce the influence of random factors, and thus show a more concise estimate of left hemisphere language capacity. Thus, a stronger correlation between language comprehension skills and the dichotic listening performance when attending to the right ear was expected. The analyses yielded a positive correlation between the right ear score in DL and language comprehension, an effect that was stronger when attending to the right ear. The present results confirm the assumption that dichotic listening with CV syllables measures an aspect of language perception and language skills that is related to general language comprehension.

Single-Stage Ear Reconstruction and Hearing Restoration Using Polyethylene Implant and Implantable Hearing Devices.

PubMed

Hempel, John Martin

2015-12-01

The use of porous polyethylene in reconstructive surgery of the auricle is becoming increasingly accepted. This is a single-stage procedure providing pleasing cosmetic rehabilitation. Further advantages are the possibility of early implantation and the lack of complications caused by harvesting costal cartilage. Additional hearing restoration using middle ear implants allows functional rehabilitation at an early stage. Thieme Medical Publishers 333 Seventh Avenue, New York, NY 10001, USA.

A New Acoustic Portal into the Odontocete Ear and Vibrational Analysis of the Tympanoperiotic Complex

DTIC Science & Technology

2010-08-01

are credited. Funding: Fleet Industrial Supply Center (FISC). Grant# N00244-08-1-0025. The funding flows from the Chief of Naval Operations...34, 35, 36 and 37). Middle Ear Function McCormick [22] studied hearing in the bottlenose dolphin (Tursiops truncatus) by measuring cochlear potentials...tympanic ligament attenuated the cochlear potentials by 18 dB with respect to the level obtained during preliminary tests, whereas removing the

Gadolinium-enhanced inner ear magnetic resonance imaging for evaluation of delayed endolymphatic hydrops, including a bilateral case.

PubMed

Fukushima, Munehisa; Oya, Ryohei; Akazawa, Hitoshi; Tsuruta, Yukinori; Inohara, Hidenori

2016-01-01

The data suggests that gadolinium-enhanced inner ear MR imaging is useful for diagnosis of delayed endolymphatic hydrops (DEH) because it is independent of inner ear function, and the size of the affected endolymphatic space is clearly enlarged. This study was performed to semi-quantitatively evaluate the endolymphatic space in patients with all types of DEH using gadolinium-enhanced inner ear magnetic resonance (MR) imaging. Seven patients (age range = 21-77 years; five female, two male) with ipsilateral DEH (n = 5), contralateral DEH (n = 1), and bilateral DEH (n = 1). All patients underwent 3T MR imaging 4 h after intravenous injection of gadolinium. Software was used to determine the size of the endolymphatic space. Pure tone audiometry and caloric testing using an electronystagmogram were carried out. One side of the endolymphatic space was dominantly extended in patients with ipsilateral DEH, and both sides of the space were extended in patients with contralateral and bilateral DEH. In patients with ipsilateral DEH, the volume ratio of endolymph to vestibule was 2.5-4.3-times that in the unaffected ear. The volume ratio of endolymph to vestibule was nearly equal in patients with contralateral and bilateral DEH.

Overexpression of EAR1 and SSH4 that encode PPxY proteins in the multivesicular body provides stability to tryptophan permease Tat2, allowing yeast cells to grow under high hydrostatic pressure

NASA Astrophysics Data System (ADS)

Hiraki, Toshiki; Usui, Keiko; Abe, Fumiyoshi

2010-12-01

Tryptophan uptake in yeast Saccharomyces cerevisiae is susceptible to high hydrostatic pressure and it limits the growth of tryptophan auxotrophic (Trp-) strains under pressures of 15-25 MPa. The susceptibility of tryptophan uptake is accounted for by the pressure-induced degradation of tryptophan permease Tat2 occurring in a Rsp5 ubiquitin ligase-dependent manner. Ear1 and Ssh4 are multivesicular body proteins that physically interact with Rsp5. We found that overexpression of either of the EAR1 or SSH4 genes enabled the Trp- cells to grow at 15-25 MPa. EAR1 and SSH4 appeared to provide stability to the Tat2 protein when overexpressed. The result suggests that Ear1 and Ssh4 negatively regulate Rsp5 on ubiquitination of Tat2. Currently, high hydrostatic pressure is widely used in bioscience and biotechnology for structurally perturbing macromolecules such as proteins and lipids or in food processing and sterilizing microbes. We suggest that hydrostatic pressure is an operative experimental parameter to screen yeast genes specifically for regulation of Tat2 through the function of Rsp5 ubiquitin ligase.

Sensory hair cell regeneration in the zebrafish lateral line.

PubMed

Lush, Mark E; Piotrowski, Tatjana

2014-10-01

Damage or destruction of sensory hair cells in the inner ear leads to hearing or balance deficits that can be debilitating, especially in older adults. Unfortunately, the damage is permanent, as regeneration of the inner ear sensory epithelia does not occur in mammals. Zebrafish and other non-mammalian vertebrates have the remarkable ability to regenerate sensory hair cells and understanding the molecular and cellular basis for this regenerative ability will hopefully aid us in designing therapies to induce regeneration in mammals. Zebrafish not only possess hair cells in the ear but also in the sensory lateral line system. Hair cells in both organs are functionally analogous to hair cells in the inner ear of mammals. The lateral line is a mechanosensory system found in most aquatic vertebrates that detects water motion and aids in predator avoidance, prey capture, schooling, and mating. Although hair cell regeneration occurs in both the ear and lateral line, most research to date has focused on the lateral line due to its relatively simple structure and accessibility. Here we review the recent discoveries made during the characterization of hair cell regeneration in zebrafish. Copyright © 2014 Wiley Periodicals, Inc.

MEKK4 Signaling Regulates Sensory Cell Development and Function in the Mouse Inner Ear

PubMed Central

Haque, Khujista; Pandey, Atul K.; Zheng, Hong-Wei; Riazuddin, Saima; Sha, Su-Hua

2016-01-01

Mechanosensory hair cells (HCs) residing in the inner ear are critical for hearing and balance. Precise coordination of proliferation, sensory specification, and differentiation during development is essential to ensure the correct patterning of HCs in the cochlear and vestibular epithelium. Recent studies have revealed that FGF20 signaling is vital for proper HC differentiation. However, the mechanisms by which FGF20 signaling promotes HC differentiation remain unknown. Here, we show that mitogen-activated protein 3 kinase 4 (MEKK4) expression is highly regulated during inner ear development and is critical to normal cytoarchitecture and function. Mice homozygous for a kinase-inactive MEKK4 mutation exhibit significant hearing loss. Lack of MEKK4 activity in vivo also leads to a significant reduction in the number of cochlear and vestibular HCs, suggesting that MEKK4 activity is essential for overall development of HCs within the inner ear. Furthermore, we show that loss of FGF20 signaling in vivo inhibits MEKK4 activity, whereas gain of Fgf20 function stimulates MEKK4 expression, suggesting that Fgf20 modulates MEKK4 activity to regulate cellular differentiation. Finally, we demonstrate, for the first time, that MEKK4 acts as a critical node to integrate FGF20-FGFR1 signaling responses to specifically influence HC development and that FGFR1 signaling through activation of MEKK4 is necessary for outer hair cell differentiation. Collectively, this study provides compelling evidence of an essential role for MEKK4 in inner ear morphogenesis and identifies the requirement of MEKK4 expression in regulating the specific response of FGFR1 during HC development and FGF20/FGFR1 signaling activated MEKK4 for normal sensory cell differentiation. SIGNIFICANCE STATEMENT Sensory hair cells (HCs) are the mechanoreceptors within the inner ear responsible for our sense of hearing. HCs are formed before birth, and mammals lack the ability to restore the sensory deficits associated with their loss. In this study, we show, for the first time, that MEKK4 signaling is essential for the development of normal cytoarchitecture and hearing function as MEKK4 signaling-deficient mice exhibit a significant reduction of HCs and a hearing loss. We also identify MEKK4 as a critical hub kinase for FGF20-FGFR1 signaling to induce HC differentiation in the mammalian cochlea. These results reveal a new paradigm in the regulation of HC differentiation and provide significant new insights into the mechanism of Fgf signaling governing HC formation. PMID:26818521

Unilateral hearing during development: hemispheric specificity in plastic reorganizations

PubMed Central

Kral, Andrej; Heid, Silvia; Hubka, Peter; Tillein, Jochen

2013-01-01

The present study investigates the hemispheric contributions of neuronal reorganization following early single-sided hearing (unilateral deafness). The experiments were performed on ten cats from our colony of deaf white cats. Two were identified in early hearing screening as unilaterally congenitally deaf. The remaining eight were bilaterally congenitally deaf, unilaterally implanted at different ages with a cochlear implant. Implanted animals were chronically stimulated using a single-channel portable signal processor for two to five months. Microelectrode recordings were performed at the primary auditory cortex under stimulation at the hearing and deaf ear with bilateral cochlear implants. Local field potentials (LFPs) were compared at the cortex ipsilateral and contralateral to the hearing ear. The focus of the study was on the morphology and the onset latency of the LFPs. With respect to morphology of LFPs, pronounced hemisphere-specific effects were observed. Morphology of amplitude-normalized LFPs for stimulation of the deaf and the hearing ear was similar for responses recorded at the same hemisphere. However, when comparisons were performed between the hemispheres, the morphology was more dissimilar even though the same ear was stimulated. This demonstrates hemispheric specificity of some cortical adaptations irrespective of the ear stimulated. The results suggest a specific adaptation process at the hemisphere ipsilateral to the hearing ear, involving specific (down-regulated inhibitory) mechanisms not found in the contralateral hemisphere. Finally, onset latencies revealed that the sensitive period for the cortex ipsilateral to the hearing ear is shorter than that for the contralateral cortex. Unilateral hearing experience leads to a functionally-asymmetric brain with different neuronal reorganizations and different sensitive periods involved. PMID:24348345

Unilateral hearing during development: hemispheric specificity in plastic reorganizations.

PubMed

Kral, Andrej; Heid, Silvia; Hubka, Peter; Tillein, Jochen

2013-01-01

The present study investigates the hemispheric contributions of neuronal reorganization following early single-sided hearing (unilateral deafness). The experiments were performed on ten cats from our colony of deaf white cats. Two were identified in early hearing screening as unilaterally congenitally deaf. The remaining eight were bilaterally congenitally deaf, unilaterally implanted at different ages with a cochlear implant. Implanted animals were chronically stimulated using a single-channel portable signal processor for two to five months. Microelectrode recordings were performed at the primary auditory cortex under stimulation at the hearing and deaf ear with bilateral cochlear implants. Local field potentials (LFPs) were compared at the cortex ipsilateral and contralateral to the hearing ear. The focus of the study was on the morphology and the onset latency of the LFPs. With respect to morphology of LFPs, pronounced hemisphere-specific effects were observed. Morphology of amplitude-normalized LFPs for stimulation of the deaf and the hearing ear was similar for responses recorded at the same hemisphere. However, when comparisons were performed between the hemispheres, the morphology was more dissimilar even though the same ear was stimulated. This demonstrates hemispheric specificity of some cortical adaptations irrespective of the ear stimulated. The results suggest a specific adaptation process at the hemisphere ipsilateral to the hearing ear, involving specific (down-regulated inhibitory) mechanisms not found in the contralateral hemisphere. Finally, onset latencies revealed that the sensitive period for the cortex ipsilateral to the hearing ear is shorter than that for the contralateral cortex. Unilateral hearing experience leads to a functionally-asymmetric brain with different neuronal reorganizations and different sensitive periods involved.

A surgical approach appropriate for targeted cochlear gene therapy in the mouse.

PubMed

Jero, J; Tseng, C J; Mhatre, A N; Lalwani, A K

2001-01-01

Therapeutic manipulations of the mammalian cochlea, including cochlear gene transfer, have been predominantly studied using the guinea pig as the experimental model. With the significant developments in mouse genomics and the availability of mutant strains of mice with well-characterized hearing loss, the mouse justifiably will be the preferred animal model for therapeutic manipulations. However, the potential advantages of the mouse model have not been fully realized due to the surgical difficulty of accessing its small cochlea. This study describes a ventral approach, instead of the routinely used postauricular approach in other rodents, for accessing the mouse middle and inner ear, and its application in cochlear gene transfer. This ventral approach enabled rapid and direct delivery of liposome-transgene complex to the mouse inner ear while avoiding blood loss, facial nerve morbidity, and mortality. Transgene expression at 3 days was detected in Reissner's membrane, spiral limbus, spiral ligament, and spiral ganglion cells, in a pattern similar to that previously described in the guinea pig. The successful access and delivery of material to the mouse cochlea and the replication of gene expression seen in the guinea pig demonstrated in this study should promote the use of the mouse in future studies investigating targeted cochlear therapy.

Analysis of chemosensory function in patients with chronic Eustachian tube dysfunction prior to and after balloon dilatation.

PubMed

Ute, Walliczek-Dworschak; Lisa, Schmierer; Brandon, Greene; Robert, Pellegrino; Philipp, Dworschak; Stuck, Boris Alexander; Christian, Güldner

2018-10-01

Eustachian tube dysfunction (ETD) affects approximately 1% of adults in the general population. Non treated Eustachian tube dysfunction can result in chronic middle ear diseases, which have been shown to significantly affect taste sensitivity. A promising treatment is balloon dilatation of the Eustachian tube. The primary aim of the present study was to investigate whether individuals with ETD had impairment in chemosensory functions, and the changes of the chemosensory function after balloon dilatation of the Eustachian tube. 26 patients (17 female, 9 male) (=56 ears) suffering from ETD with a mean age of 39±15years were included in the present study. 20 patients (76%) returned to be evaluated at the follow up (=40 ears) 51±22days after balloon dilatation. For pre- and post operation, gustatory function was measured with a lateralized gustatory test with the taste strips and olfactory function was tested by means of the Sniffin' Sticks test battery (threshold, discrimination and identification (ID)). Patients' baseline taste function (summed taste score 9.8±3.5 (mean±SD)) was significantly impaired compared to normative data (summed taste score 12.4±2.3; p=0.002). After balloon dilatation of the Eustachian tube, the taste function remained stable (summed taste score 9.4±4.3; p=0.814). Olfactory function (odor ID, summed score (TDI)) improved postoperatively (TDI 32.4±3.6) compared to pre-operative scores (TDI 33.6±4.0; p=0.012), but not to a clinically relevant extent. This study suggests, that patients suffering from ETD exhibit reduced taste scores. Balloon dilatation of the Eustachian tube does not seem to influence gustatory function, but olfactory function showed improvement. Copyright © 2018 Elsevier B.V. All rights reserved.

Molecular characterization and expression analysis of Triticum aestivum squamosa-promoter binding protein-box genes involved in ear development.

PubMed

Zhang, Bin; Liu, Xia; Zhao, Guangyao; Mao, Xinguo; Li, Ang; Jing, Ruilian

2014-06-01

Wheat (Triticum aestivum L.) is one of the most important crops in the world. Squamosa-promoter binding protein (SBP)-box genes play a critical role in regulating flower and fruit development. In this study, 10 novel SBP-box genes (TaSPL genes) were isolated from wheat ((Triticum aestivum L.) cultivar Yanzhan 4110). Phylogenetic analysis classified the TaSPL genes into five groups (G1-G5). The motif combinations and expression patterns of the TaSPL genes varied among the five groups with each having own distinctive characteristics: TaSPL20/21 in G1 and TaSPL17 in G2 mainly expressed in the shoot apical meristem and the young ear, and their expression levels responded to development of the ear; TaSPL6/15 belonging to G3 were upregulated and TaSPL1/23 in G4 were downregulated during grain development; the gene in G5 (TaSPL3) expressed constitutively. Thus, the consistency of the phylogenetic analysis, motif compositions, and expression patterns of the TaSPL genes revealed specific gene structures and functions. On the other hand, the diverse gene structures and different expression patterns suggested that wheat SBP-box genes have a wide range of functions. The results also suggest a potential role for wheat SBP-box genes in ear development. This study provides a significant beginning of functional analysis of SBP-box genes in wheat. © 2014 The Authors. Journal of Integrative Plant Biology Published by Wiley Publishing Asia Pty Ltd on behalf of Institute of Botany, Chinese Academy of Sciences.

Predicting binaural responses from monaural responses in the gerbil medial superior olive

PubMed Central

Plauška, Andrius; Borst, J. Gerard

2016-01-01

Accurate sound source localization of low-frequency sounds in the horizontal plane depends critically on the comparison of arrival times at both ears. A specialized brainstem circuit containing the principal neurons of the medial superior olive (MSO) is dedicated to this comparison. MSO neurons are innervated by segregated inputs from both ears. The coincident arrival of excitatory inputs from both ears is thought to trigger action potentials, with differences in internal delays creating a unique sensitivity to interaural time differences (ITDs) for each cell. How the inputs from both ears are integrated by the MSO neurons is still debated. Using juxtacellular recordings, we tested to what extent MSO neurons from anesthetized Mongolian gerbils function as simple cross-correlators of their bilateral inputs. From the measured subthreshold responses to monaural wideband stimuli we predicted the rate-ITD functions obtained from the same MSO neuron, which have a damped oscillatory shape. The rate of the oscillations and the position of the peaks and troughs were accurately predicted. The amplitude ratio between dominant and secondary peaks of the rate-ITD function, captured in the width of its envelope, was not always exactly reproduced. This minor imperfection pointed to the methodological limitation of using a linear representation of the monaural inputs, which disregards any temporal sharpening occurring in the cochlear nucleus. The successful prediction of the major aspects of rate-ITD curves supports a simple scheme in which the ITD sensitivity of MSO neurons is realized by the coincidence detection of excitatory monaural inputs. PMID:27009164

β1- and β2-adrenergic stimulation-induced electrogenic transport by human endolymphatic sac epithelium and its clinical implications

PubMed Central

Kim, Bo Gyung; Kim, Jin Young; Jung, JinSei; Moon, In Seok; Yoon, Joo-Heon; Choi, Jae Young; Kim, Sung Huhn

2017-01-01

The endolymphatic sac (ES) is a cystic structure of the inner ear connected to the cochlea and vestibule, which plays a role in regulating ion homeostasis in inner ear fluid. Disruption of ion homeostasis can cause inner ear disorders with hearing loss and dizziness, such as Meniere’s disease. Herein, we found, for the first time, functional evidence for the involvement of β1- and β2-adrenergic receptors in apical electrogenic ion transport by human ES epithelium by using electrophysiological/pharmacological and molecular biological methods, which were dependent on K+ and Cl− ion transport. The apical electrogenic transport was absent or very weak in ES epithelia of patients with Meniere’s disease. These results suggested that adrenergic stimulation via β1- and β2-adrenergic receptors in the human ES was involved in regulation of inner ear fluid ion homeostasis and impairment of this response could be a pathological mechanism of Meniere’s disease. PMID:28165045

Modification of the wake behind a bat ear with and without tubercles

NASA Astrophysics Data System (ADS)

Petrin, Christopher; Elbing, Brian

2015-11-01

The Mexican Free-Tailed Bat (Tadarida brasiliensis) is a highly aerobatic bat, known to dive from altitudes of several thousand feet into their home caves, reaching estimated speeds of 27 m/s (Davis et al., Ecological Monographs, 32, 1962). A series of small tubercles have been observed on the leading edge of the bat's ear, which mimic the pattern of tubercles found on the fins of the humpback whale (Megaptera novaeangliae). The tubercles on the whale fins have been proven to delay stall on the fin and allow the whale to retain better control during dives. The goal of the current study is to assess whether the bat ear tubercles fulfill a similar purpose of improving flow control, particularly at high angles of attack. This was accomplished by acquiring PIV measurements of the bat ear wake with and without the tubercles. The velocity profiles were used to assess the drag and lift as a function of angle of attack. These results will be presented and the impact of the tubercles assessed.

Canal wall reconstruction and preservation in the surgical management of cholesteatoma in children with Down's syndrome.

PubMed

Nash, Robert; Possamai, Victoria; Maskell, Scott; Bailey, Martin; Albert, David

2014-10-01

Down's syndrome is associated with poor Eustachian tube function, and an increased incidence of cholesteatoma. The only previously published case series suggests that 'canal wall preserving' procedures are only rarely suitable for the management of cholesteatoma in this population. We conducted a retrospective review of the hospital's clinical records database to identify patients with Down's syndrome and cholesteatoma. These patients' notes were then reviewed. We identified nine patients with Down's syndrome who had undergone surgical management of cholesteatoma over a twelve year period. Three patients had bilateral disease, meaning twelve ears were treated. Seven ears were initially treated with 'canal wall down' procedures. Four out of five of the remaining ears were successfully treated using 'canal wall preservation' or 'canal wall reconstruction', with one ear requiring subsequent conversion to a 'canal wall down' approach. Canal wall preservation/reconstruction is feasible in patients with Down's syndrome, even when cholesteatoma extends into the mastoid. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.

Comparative analysis of ear-hole closure identifies epimorphic regeneration as a discrete trait in mammals

PubMed Central

Gawriluk, Thomas R.; Simkin, Jennifer; Thompson, Katherine L.; Biswas, Shishir K.; Clare-Salzler, Zak; Kimani, John M.; Kiama, Stephen G.; Smith, Jeramiah J.; Ezenwa, Vanessa O.; Seifert, Ashley W.

2016-01-01

Why mammals have poor regenerative ability has remained a long-standing question in biology. In regenerating vertebrates, injury can induce a process known as epimorphic regeneration to replace damaged structures. Using a 4-mm ear punch assay across multiple mammalian species, here we show that several Acomys spp. (spiny mice) and Oryctolagus cuniculus completely regenerate tissue, whereas other rodents including MRL/MpJ ‘healer' mice heal similar injuries by scarring. We demonstrate ear-hole closure is independent of ear size, and closure rate can be modelled with a cubic function. Cellular and genetic analyses reveal that injury induces blastema formation in Acomys cahirinus. Despite cell cycle re-entry in Mus musculus and A. cahirinus, efficient cell cycle progression and proliferation only occurs in spiny mice. Together, our data unite blastema-mediated regeneration in spiny mice with regeneration in other vertebrates such as salamanders, newts and zebrafish, where all healthy adults regenerate in response to injury. PMID:27109826

Amplification in the rehabilitation of unilateral deafness: speech in noise and directional hearing effects with bone-anchored hearing and contralateral routing of signal amplification.

PubMed

Lin, Li-Mei; Bowditch, Stephen; Anderson, Michael J; May, Bradford; Cox, Kenneth M; Niparko, John K

2006-02-01

Vibromechanical stimulation with a semi-implantable bone conductor (Entific BAHA device) overcomes some of the head-shadow effects in unilateral deafness. What specific rehabilitative benefits are observed when the functional ear exhibits normal hearing versus moderate sensorineural hearing loss (SNHL)? The authors conducted a prospective trial of subjects with unilateral deafness in a tertiary care center. This study comprised adults with unilateral deafness (pure-tone average [PTA] > 90 dB; Sp.D. < 20%) and either normal monaural hearing (n = 18) or moderate SNHL (PTA = 25-50 dB: Sp.D. > 75%) in the contralateral functional ear (n = 5). Subjects were fit with contralateral routing of signal (CROS) devices for 1 month and tested before (mastoid) implantation, fitting, and testing with a bone-anchored hearing aid (BAHA). Outcome measures were: 1) subjective benefit; 2) source localization tests (Source Azimuth Identification in Noise Test [SAINT]); 3) speech discrimination in quiet and in noise assessed with Hearing In Noise Test (HINT) protocols. There was consistent satisfaction with BAHA amplification and poor acceptance of CROS amplification. General directional hearing decreased with CROS use and was unchanged by BAHA and directional microphone aids. Relative to baseline and CROS, BAHA produced significantly better speech recognition in noise. Twenty-two of 23 subjects followed up in this study continue to use their BAHA device over an average follow-up period of 30.24 months (range, 51-12 months). BAHA amplification on the side of a deaf ear yields greater benefit in subjects with monaural hearing than does CROS amplification. Advantages likely related to averting the interference of speech signals delivered to the better ear, as occurs with conventional CROS amplification, while alleviating the negative head-shadow effects of unilateral deafness. The advantages of head-shadow reduction in enhancing speech recognition with noise in the hearing ear outweigh disadvantages inherent in head-shadow reduction that can occur by introducing noise from the deaf side. The level of hearing impairment correlates with incremental benefit provided by the BAHA. Patients with a moderate SNHL in the functioning ear perceived greater increments in benefit, especially in background noise, and demonstrated greater improvements in speech understanding with BAHA amplification.

The LuxS/AI-2 Quorum-Sensing System of Streptococcus pneumoniae Is Required to Cause Disease, and to Regulate Virulence- and Metabolism-Related Genes in a Rat Model of Middle Ear Infection.

PubMed

Yadav, Mukesh K; Vidal, Jorge E; Go, Yoon Y; Kim, Shin H; Chae, Sung-Won; Song, Jae-Jun

2018-01-01

Objective: Streptococcus pneumoniae colonizes the nasopharynx of children, and from nasopharynx it could migrate to the middle ear and causes acute otitis media (AOM). During colonization and AOM, the pneumococcus forms biofilms. In vitro biofilm formation requires a functional LuxS/AI-2 quorum-sensing system. We investigated the role of LuxS/AI-2 signaling in pneumococcal middle ear infection, and identified the genes that are regulated by LuxS/AI-2 during pneumococcal biofilm formation. Methods: Streptococcus pneumoniae D39 wild-type and an isogenic D39Δ luxS strain were utilized to evaluate in vitro biofilm formation, and in vivo colonization and epithelial damage using a microtiter plate assay and a rat model of pneumococcal middle ear infection, respectively. Biofilm structures and colonization and epithelial damage were evaluated at the ultrastructural level by scanning electron microscopy and confocal microscopy. Microarrays were used to investigate the global genes that were regulated by LuxS/AI-2 during biofilm formation. Results: The biofilm biomass and density of D39Δ luxS were significantly ( p < 0.05) lower than those of D39 wild-type. SEM and confocal microscopy revealed that D39Δ luxS formed thin biofilms in vitro compared with D39 wild-type. The in vivo model of middle ear infection showed that D39Δ luxS resulted in ~60% less ( p < 0.05) bacterial colonization than the wild-type. SEM analysis of the rat middle ears revealed dense biofilm-like cell debris deposited on the cilia in wild-type D39-infected rats. However, little cell debris was deposited in the middle ears of the D39Δ luxS -inoculated rats, and the cilia were visible. cDNA-microarray analysis revealed 117 differentially expressed genes in D39Δ luxS compared with D39 wild-type. Among the 66 genes encoding putative proteins and previously characterized proteins, 60 were significantly downregulated, whereas 6 were upregulated. Functional annotation revealed that genes involved in DNA replication and repair, ATP synthesis, capsule biosynthesis, cell division, the cell cycle, signal transduction, transcription regulation, competence, virulence, and carbohydrate metabolism were downregulated in the absence of LuxS/AI-2. Conclusion: The S. pneumoniae LuxS/AI-2 quorum-sensing system is necessary for biofilm formation and the colonization of the ear epithelium, and caused middle ear infection in the rat model. LuxS/AI-2 regulates the expression of the genes involved in virulence and bacterial fitness during pneumococcal biofilm formation.

Wideband acoustic immittance for assessing middle ear functioning for preterm neonates in the neonatal intensive care unit.

PubMed

Gouws, Nandel; Swanepoel, De Wet; De Jager, Leigh Biagio

2017-06-28

The primary aim of newborn hearing screening is to detect permanent hearing loss. Because otoacoustic emissions (OAEs) and automated auditory brainstem response (AABR) are sensitive to hearing loss, they are often used as screening tools. On the other hand, false-positive results are most often because of transient outer- and middle ear conditions. Wideband acoustic immittance (WAI), which includes physical measures known as reflectance and absorbance, has shown potential for accurate assessment of middle ear function in young infants. The main objective of this study was to determine the feasibility of WAI as a diagnostic tool for assessing middle ear functioning in preterm neonates in the neonatal intensive care unit (NICU) designed for premature and ill neonates. A further objective was to indicate the difference between the reflectance values of tones and click stimuli. Fifty-six at-risk neonates (30 male and 26 female), with a mean age at testing of 35.6 weeks (range: 32-37 weeks) and a standard deviation of 1.6 from three private hospitals, who passed both the distortion product otoacoustic emission (DPOAE) and AABR tests, were evaluated prior to discharge from the NICU. Neonates who presented with abnormal DPOAE and AABR results were excluded from the study. WAI was measured by using chirp and tone stimuli. In addition to reflectance, the reflectance area index (RAI) values were calculated. Both tone and chirp stimuli indicated high-power reflectance values below a frequency of 1.5 kHz. Median reflectance reached a minimum of 0.67 at 1 kHz - 2 kHz but increased to 0.7 below 1 kHz and 0.72 above 2 kHz for the tone stimuli. For chirp stimuli, the median reflectance reached a minimum of 0.51 at 1 kHz - 2 kHz but increased to 0.68 below 1 kHz and decreased to 0.5 above 2 kHz. A comparison between the present study and previous studies on WAI indicated a substantial variability across all frequency ranges. These WAI measurements conducted on at-risk preterm NICU neonates (mean age at testing: 35.6 weeks, range: 32-37 weeks) identified WAI patterns not previously reported in the literature. High reflective values were obtained across all frequency ranges. The age of the neonates when tested might have influenced the results. The neonates included in the present study were very young preterm neonates compared to the ages of neonates in previous studies. WAI measured in at-risk preterm neonates in the NICU was variable with environmental and internal noise influences. Transient conditions affecting the sound-conduction pathway might have influenced the results. Additional research is required to investigate WAI testing in ears with and without middle ear dysfunction. The findings of the current study imply that in preterm neonates it was not possible to determine the feasibility of WAI as a diagnostic tool to differentiate between ears with and without middle ear pathology.

Morin hydrate promotes inner ear neural stem cell survival and differentiation and protects cochlea against neuronal hearing loss.

PubMed

He, Qiang; Jia, Zhanwei; Zhang, Ying; Ren, Xiumin

2017-03-01

We aimed to investigate the effect of morin hydrate on neural stem cells (NSCs) isolated from mouse inner ear and its potential in protecting neuronal hearing loss. 3-(4,5-dimethyl-2-thiazolyl)-2,5-diphenyl-2-H-tetrazolium bromide (MTT) and bromodeoxyuridine incorporation assays were employed to assess the effect of morin hydrate on the viability and proliferation of in vitro NSC culture. The NSCs were then differentiated into neurons, in which neurosphere formation and differentiation were evaluated, followed by neurite outgrowth and neural excitability measurements in the subsequent in vitro neuronal network. Mechanotransduction of cochlea ex vivo culture and auditory brainstem responses threshold and distortion product optoacoustic emissions amplitude in mouse ototoxicity model were also measured following gentamicin treatment to investigate the protective role of morin hydrate against neuronal hearing loss. Morin hydrate improved viability and proliferation, neurosphere formation and neuronal differentiation of inner ear NSCs, and promoted in vitro neuronal network functions. In both ex vivo and in vivo ototoxicity models, morin hydrate prevented gentamicin-induced neuronal hearing loss. Morin hydrate exhibited potent properties in promoting growth and differentiation of inner ear NSCs into functional neurons and protecting from gentamicin ototoxicity. Our study supports its clinical potential in treating neuronal hearing loss. © 2016 The Authors. Journal of Cellular and Molecular Medicine published by John Wiley & Sons Ltd and Foundation for Cellular and Molecular Medicine.

Requirement for Jagged1-Notch2 signaling in patterning the bones of the mouse and human middle ear.

PubMed

Teng, Camilla S; Yen, Hai-Yun; Barske, Lindsey; Smith, Bea; Llamas, Juan; Segil, Neil; Go, John; Sanchez-Lara, Pedro A; Maxson, Robert E; Crump, J Gage

2017-05-31

Whereas Jagged1-Notch2 signaling is known to pattern the sensorineural components of the inner ear, its role in middle ear development has been less clear. We previously reported a role for Jagged-Notch signaling in shaping skeletal elements derived from the first two pharyngeal arches of zebrafish. Here we show a conserved requirement for Jagged1-Notch2 signaling in patterning the stapes and incus middle ear bones derived from the equivalent pharyngeal arches of mammals. Mice lacking Jagged1 or Notch2 in neural crest-derived cells (NCCs) of the pharyngeal arches display a malformed stapes. Heterozygous Jagged1 knockout mice, a model for Alagille Syndrome (AGS), also display stapes and incus defects. We find that Jagged1-Notch2 signaling functions early to pattern the stapes cartilage template, with stapes malformations correlating with hearing loss across all frequencies. We observe similar stapes defects and hearing loss in one patient with heterozygous JAGGED1 loss, and a diversity of conductive and sensorineural hearing loss in nearly half of AGS patients, many of which carry JAGGED1 mutations. Our findings reveal deep conservation of Jagged1-Notch2 signaling in patterning the pharyngeal arches from fish to mouse to man, despite the very different functions of their skeletal derivatives in jaw support and sound transduction.

Late skin damage in rabbits and monkeys after exposure to particulate radiations

NASA Astrophysics Data System (ADS)

Bergtold, D. S.; Cox, A. B.; Lett, J. T.; Su, C. M.

Skin biopsies were taken from the central regions of the ears of New Zealand white rabbits following localized exposure of one ear of each rabbit to 530 MeV/amu Ar or 365 MeV/amu Ne ions. The unirradiated ears served as controls. Biopsies were taken also from the chests and inner thighs of rhesus monkeys after whole-body exposure to 32 MeV protons and from unirradiated control animals. The linear energy transfers (LET∞'s) for the radiations were 90 +/- 5, 35 +/- 3, and ~1.2 keV/μm, respectively. In the rabbit studies, explants were removed with a 2 mm diameter dermal punch at post-irradiation times up to five years after exposure. Similar volumes of monkey tissue were taken from skin samples excised surgically 16-18 years following proton irradiation. Fibroblast cultures were initiated from the explants and were propagated in vitro until terminal senescence (cessation of cell division) occurred. Cultures from irradiated tissue exhibited decreases in doubling potential that were dependent on radiation dose and LET∞ and seemed to reflect damage to stem cell populations. The implications of these results for astronauts exposed to heavy ions and/or protons in space include possible manifestations of residual effects in the skin many years after exposure (e.g. unsatisfactory responses to trauma or surgery).

Twins and transsexualism: an update and a preview; research reviews: conjoined twins, angiographic lesions, single versus double embryo transfer; headlines: school placement legislation, Junior Taekwondo Olympics, prosthetic ears, murder victim.

PubMed

Segal, Nancy L

2007-12-01

In recent years, there has been growing appreciation for the complexity of gender identity. Focusing on monozygotic (MZ) twins discordant for transsexualism can offer clues to events that may trigger this behavioral difference, offering new information about critical underlying factors. An update of twin research in this area is provided, together with a preview of a compelling new film, 'Red Without Blue.' Next, twin study findings on the topics of conjoined twinning, angiographic lesions and embryo transfer are provided. This is followed by a survey of newsworthy twins and twin-related events.

Stochastic information transfer from cochlear implant electrodes to auditory nerve fibers

NASA Astrophysics Data System (ADS)

Gao, Xiao; Grayden, David B.; McDonnell, Mark D.

2014-08-01

Cochlear implants, also called bionic ears, are implanted neural prostheses that can restore lost human hearing function by direct electrical stimulation of auditory nerve fibers. Previously, an information-theoretic framework for numerically estimating the optimal number of electrodes in cochlear implants has been devised. This approach relies on a model of stochastic action potential generation and a discrete memoryless channel model of the interface between the array of electrodes and the auditory nerve fibers. Using these models, the stochastic information transfer from cochlear implant electrodes to auditory nerve fibers is estimated from the mutual information between channel inputs (the locations of electrodes) and channel outputs (the set of electrode-activated nerve fibers). Here we describe a revised model of the channel output in the framework that avoids the side effects caused by an "ambiguity state" in the original model and also makes fewer assumptions about perceptual processing in the brain. A detailed comparison of how different assumptions on fibers and current spread modes impact on the information transfer in the original model and in the revised model is presented. We also mathematically derive an upper bound on the mutual information in the revised model, which becomes tighter as the number of electrodes increases. We found that the revised model leads to a significantly larger maximum mutual information and corresponding number of electrodes compared with the original model and conclude that the assumptions made in this part of the modeling framework are crucial to the model's overall utility.

Conductive hearing loss and middle ear pathology in young infants referred through a newborn universal hearing screening program in Australia.

PubMed

Aithal, Sreedevi; Aithal, Venkatesh; Kei, Joseph; Driscoll, Carlie

2012-10-01

Although newborn hearing screening programs have been introduced in most states in Australia, the prevalence of conductive hearing loss and middle ear pathology in the infants referred through these programs is not known. This study was designed to (1) evaluate the prevalence of conductive hearing loss and middle ear pathology in infants referred by a newborn hearing screening program in north Queensland, (2) compare prevalence rates of conductive hearing loss and middle ear pathology in indigenous and nonindigenous infants, and (3) review the outcomes of those infants diagnosed with conductive hearing loss and middle ear pathology. Retrospective chart review of infants referred to the Audiology Department of The Townsville Hospital was conducted. Chart review of 234 infants referred for one or both ears from a newborn hearing screening program in north Queensland was conducted. A total of 211 infants attended the diagnostic appointment. Review appointments to monitor hearing status were completed for 46 infants with middle ear pathology or conductive hearing loss. Diagnosis of hearing impairment was made using an age-appropriate battery of audiological tests. Results were analyzed for both initial and review appointments. Mean age at initial diagnostic assessment was 47.5 days (SD = 31.3). Of the 69 infants with middle ear pathology during initial diagnostic assessment, 18 had middle ear pathology with normal hearing, 47 had conductive hearing loss, and 4 had mixed hearing loss. Prevalence of conductive hearing loss in the newborns was 2.97 per 1,000 while prevalence of middle ear pathology (with or without conductive hearing loss) was 4.36 per 1,000. Indigenous Australians or Aboriginal and Torres Strait Islander (ATSI) infants had a significantly higher prevalence of conductive hearing loss and middle ear pathology than non-ATSI infants (35.19 and 44.45% vs 17.83 and 28.66%, respectively). ATSI infants also showed poor resolution of conductive hearing loss over time with 66.67% of ATSI infants reviewed showing persistent conductive hearing loss compared to 17.86% of non-ATSI infants. Medical management of 17 infants with persistent conductive hearing loss included monitoring, antibiotic treatment, examination under anesthesia, and grommet insertion. Conductive hearing loss was found to be a common diagnosis among infants referred through screening. ATSI infants had significantly higher rates of middle ear pathology and conductive hearing loss at birth and showed poor resolution of middle ear pathology over time compared to non-ATSI infants. Future research using a direct measure of middle ear function as an adjunct to the automated auditory brainstem response screening tool to distinguish conductive from sensorineural hearing loss may facilitate prioritization of infants for assessment, thus reducing parental anxiety and streamlining the management strategies for the respective types of hearing loss. American Academy of Audiology.

Demonstration of extrapulmonary activity of angiotensin converting enzyme in intact tissue preparations.

PubMed Central

Lembeck, F.; Griesbacher, T.; Eckhardt, M.

1990-01-01

1. The activity of angiotensin converting enzyme (ACE) has been studied on functional parameters of intact isolated preparations of extrapulmonary tissues. The conversion of angiotensin I (A I) to angiotensin II (A II) and the cleavage of bradykinin (BK) were used as indicators of ACE activity. Captopril was employed as a specific inhibitor of ACE. 2. Captopril augmented the BK-induced contractions of the rat isolated uterus, the BK- and substance P-induced contractions of the guinea-pig ileum, and the BK-induced venoconstriction in the isolated perfused ear of the rabbit. Degradation of BK by ACE was calculated to be 52% in the rat uterus and 75% in the rabbit perfused ear. 3. Captopril inhibited the A I-induced contractions of the rat isolated colon, the A I-induced vasoconstriction in the isolated perfused ear of the rabbit and the rise in blood pressure induced by i.a. injections of A I in pithed rats. Conversion of A I to A II was calculated to be 13% in the rat colon and 26% in the rabbit perfused ear. 4. From estimations of the A II activity (bioassay on the rat colon) in the effluent of the perfused ear of the rabbit after injections of A I into the arterial inflow cannula it was calculated that approximately one tenth of A I was converted to A II during a single passage through the ear (less than 15 s).(ABSTRACT TRUNCATED AT 250 WORDS) PMID:2164861

Retroauricular skin: a flaps bank for ear reconstruction.

PubMed

Cordova, A; D'Arpa, S; Pirrello, R; Giambona, C; Moschella, F

2008-01-01

The retroauricular skin has always been given much attention by the reconstructive surgeon for ear and face reconstruction because it is richly vascularised, as many anatomical investigations show, it is hidden behind the ear, its skin is very similar to that of ear and face. All these reasons make it an ideal donor site for ear reconstruction. The authors propose their own algorithm for reconstruction of every kind of anterior defects of the auricle with different Retroauricular Island Flaps (RIFs) based on the location and size of the defect developed over a 16 years single institution's experience with a series of 216 consecutive cases. 216 patients have undergone ear reconstruction with RIFs from 1999 to 2006. In 52 a Superior Pedicle RIF (SP-RIF) was used for defects of the upper half of the auricle. In 68 cases a Perforator RIF (P-RIF) was used for conchal reconstruction. In 96 cases an Inferior Pedicle RIF (IP-RIF) was used for reconstruction of nonmarginal and superficial marginal defects of the auricle. No flap failure was recorded. Excellent morphological reconstruction was obtained with these flaps with no sequealae at the donor site in terms of form and function. Only in the case of P-RIFs the sulcus becomes flat in its central part, but this has never affected the possibility of wearing spectacles. The SP-RIFs may sometimes show some signs of venous stasis that invariably resolve in the first two postoperative days. The retroauricular skin may be considered a flaps bank for ear reconstruction. It offers in fact a great variety of island flaps that are suitable for every kind of loss of substance of the ear, have a safe vascularisation, skin of similar colour and texture, are easy to harvest under local anaesthesia on an outpatient basis and cause no relevant morbidity at the donor site. Location and size of the defects lead the choice between the different types of RIFs.

Effect of low level laser therapy (LLLT) on vestibular system after gentamicin ototoxicity

NASA Astrophysics Data System (ADS)

Rhee, ChungKu; Hyun, Jai-Hwan; Suh, Myung-Whan; Ahn, Jin Chul; Jung, Jae Yun

2013-03-01

Aim: To develop a bilateral vestibulopathy animal model induced by gentamicin using RS rat and to see the effect of LLLT on this bilateral vestibulopathy model. Method: RS rats were divided into 3 groups, control group (C), laser group (L), and histology group (H). All animals in the 3 groups received gentamicin (GM) 110 mg/kg, intravenously once daily for 3 days. The animals underwent sinusoidal oscillation about a vertical axis before the GM injection, 1, 3, and 7 days post injections. Transcanal low level laser therapy (LLLT) was irradiated to left ear canal for 7 days, starting 1 day post the GM injection. The H group animals were irradiated into the left ear of L group for 3 days, starting 1 day post GM injections for 3 days. C and L groups were sacrifice on 9th day and H group was sacrificed on 7th day. Results: The gain of the C group was significantly decreased in 3 and 7 days. The gain of the right ear of L group was decreased significantly in 3 and 7 days. The gain of left ear of L group was decreased in 3 days post LLLT but the decreased gain was improved significantly comparing to the level of 7 days gain of right ear and it was much closer to the pre-GM level. The average number of cells in cupula of H group after laser treatment for 3 days was significantly lower in non laser treated right ear comparing to the laser treated left ear and ears of the normal rats. Conclusion: The present study demonstrated that LLLT restores vestibular function and vestibular hair cells in rats post gentamicin induced ototoxic damage. LLLT may have clinical implications in the treatment of various vestibular dysfunction. Further studies are essential to verify the exact mechanisms and the most effective application of LLLT to rescue vestibular dysfunction.

Performance and retention of lightweight satellite radio tags applied to the ears of polar bears (Ursus maritimus)

USGS Publications Warehouse

Wiig, Øystein; Born, Erik W.; Laidre, Kristin L.; Dietz, Rune; Jensen, Mikkel Villum; Durner, George M.; Pagano, Anthony M.; Regehr, Eric V.; St. Martin, Michelle; Atkinson, Stephen N.; Dyck, Markus

2017-01-01

BackgroundSatellite telemetry studies provide information that is critical to the conservation and management of species affected by ecological change. Here we report on the performance and retention of two types (SPOT-227 and SPOT-305A) of ear-mounted Argos-linked satellite transmitters (i.e., platform transmitter terminal, or PTT) deployed on free-ranging polar bears in Eastern Greenland, Baffin Bay, Kane Basin, the southern Beaufort Sea, and the Chukchi Sea during 2007–2013.ResultsTransmissions from 142 out of 145 PTTs deployed on polar bears were received for an average of 69.3 days. The average functional longevity, defined as the number of days they transmitted while still attached to polar bears, for SPOT-227 was 56.8 days and for SPOT-305A was 48.6 days. Thirty-four of the 142 (24%) PTTs showed signs of being detached before they stopped transmitting, indicating that tag loss was an important aspect of tag failure. Furthermore, 10 of 26 (38%) bears that were re-observed following application of a PTT had a split ear pinna, suggesting that some transmitters were detached by force. All six PTTs that were still on bears upon recapture had lost the antenna, which indicates that antenna breakage was a significant contributor to PTT failure. Finally, only nine of the 142 (6%) PTTs—three of which were still attached to bears—had a final voltage reading close to the value indicating battery exhaustion. This suggests that battery exhaustion was not a major factor in tag performance.ConclusionsThe average functional longevity of approximately 2 months for ear-mounted PTTs (this study) is poor compared to PTT collars fitted to adult female polar bears, which can last for several years. Early failure of the ear-mounted PTTs appeared to be caused primarily by detachment from the ear or antenna breakage. We suggest that much smaller and lighter ear-mounted transmitters are necessary to reduce the risk of tissue irritation, tissue damage, and tag detachment, and with a more robust antenna design. Our results are applicable to other tag types (e.g., iridium and VHF systems) and to research on other large mammals that cannot wear radio collars.

Relationship Between Hair Cell Loss and Hearing Loss in Fishes.

PubMed

Smith, Michael E

2016-01-01

Exposure to intense sound or ototoxic chemicals can damage the auditory hair cells of vertebrates, resulting in hearing loss. Although the relationship between such hair cell damage and auditory function is fairly established for terrestrial vertebrates, there are limited data available to understand this relationship in fishes. Although investigators have measured either the morphological damage of the inner ear or the functional deficits in the hearing of fishes, very few have directly measured both in an attempt to find a relationship between the two. Those studies that have examined both auditory hair cell damage in the inner ear and the resulting hearing loss in fishes are reviewed here. In general, there is a significant linear relationship between the number of hair cells lost and the severity of hearing threshold shifts, although this varies between species and different hair cell-damaging stimuli. After trauma to the fish ear, auditory hair cells are able to regenerate to control level densities. With this regeneration also comes a restoration of hearing. Thus there is also a significant relationship between hair cell recovery and hearing recovery in fishes.

Sonotubometry, a useful tool for the evaluation of the Eustachian tube ventilatory function

PubMed Central

Borangiu, A; Popescu, CR; Purcarea, VL

2014-01-01

From the three Eustachian tube (ET) functions: middle ear protection, secretion clearance and middle ear ventilation, the ventilatory function is unanimously considered the most important one, because proper hearing is established only when tympanic membrane compliance is normal. This requires equilibrium between the middle ear and ambient gas pressure, which makes the normal functioning of active ET opening of critical importance. There are several methods and tests that can assess such a complex and variable mechanism. Sonotubometry is one such method; despite the fact that it has been continuously improved in the last 20 years, it is not yet systematically used to evaluate the ET ventilatory function, because its measurement pattern, context mapping (patient, clinic data, medication, treatment), validation, reproducibility and value for clinic practice, have not yet been fully consolidated and integrated in a knowledge-based, service-oriented system, that can provide decision support or even diagnostic. The paper reviews the role of tubal sonometry as a non-invasive, physiologic and easy to use method in assessing the ventilatory function and investigates the validity and reproducibility of a measuring pattern and test in a group of children. The paper describes the test pattern used, and the computer-based platform based on: (1) Digital Signal Processing (DSP) for sound acquisition and low-level processing; (2) Artificial Intelligence techniques to extract significant sound features from sonotubograms and learn a manifold context database. Results are reported from test series carried out in healthy children; a similar study between tests is included in the final Discussions section. PMID:25713631

Effect of Microgravity on Afferent Innervation

NASA Technical Reports Server (NTRS)

1998-01-01

Presentations and publications are: (1) an audiovisual summary web presentation on results from SLM-MIR avian experiments. A color presentation summarizing results from the SLM-MIR and STS-29 avian experiments; (2) color threshold and ratio of S 100B MAP5, NF68/200, GABA and GAD; (3) chicken (Gallus domesticus) inner ear afferents; (4) microgravity in the STS-29 Space Shuttle Discovery affected the vestibular system of chick embryos; (5) expression of S 100B in sensory and secretory cells of the vertebrate inner ear; (6) otoconia biogenesis, phylogeny, composition and functional attributes;(7) the glycan keratin sulfate in inner ear crystals; (8) elliptical-P cells in the avian perilymphatic interface of the tegmentum vasculosum; and (9) LAMP2c and S100B upregulation in brain stem after VIIIth nerve deafferentation.

Evidence and evidence gaps in the treatment of Eustachian tube dysfunction and otitis media

PubMed Central

Teschner, Magnus

2016-01-01

Evidence-based medicine is an approach to medical treatment intended to optimize patient-oriented decision-making on the basis of empirically proven effectiveness. For this purpose, a classification system has been established to categorize studies – and hence therapy options – in respect of associated evidence according to defined criteria. The Eustachian tube connects the nasopharynx with the middle ear cavity. Its key function is to ensure middle ear ventilation. Compromised ventilation results in inflammatory middle ear disorders. Numerous evidence-based therapy options are available for the treatment of impaired middle ear ventilation and otitis media, the main therapeutic approach being antibiotic treatment. More recent procedures such as balloon dilation of the Eustachian tube have also shown initial success but must undergo further evaluation with regard to evidence. There is, as yet, no evidence for some of the other long-established procedures. Owing to the multitude of variables, the classification of evidence levels for various treatment approaches calls for highly diversified assessment. Numerous evidence-based studies are therefore necessary in order to evaluate the evidence pertaining to existing and future therapy solutions for impaired middle ear ventilation and otitis media. If this need is addressed, a wealth of implications can be expected for therapeutic approaches in the years to come. PMID:28025605

Vestibular evoked myogenic potential according to middle ear condition in chronic otitis media with tympanic membrane perforation.

PubMed

Lee, Jun Seok; Lee, Sun Kyu; Shin, Il Ho; Yeo, Seung Geun; Park, Moon Suh; Byun, Jae Yong

2014-01-01

Vestibular evoked myogenic potential (VEMP) function results can vary between individuals with different middle ear conditions. Therefore, by analyzing VEMP results after paper patching, we can predict the condition of the middle ear in chronic otitis media (COM) patients. VEMP responses decrease with impairment of sound transmission, such as in conductive hearing loss (CHL). COM with tympanic membrane (TM) perforation is a common disorder that causes various degrees of CHL. The aim of this study was to evaluate and clarify the VEMP responses in patients with COM with different middle ear pathology. This study included 50 patients with unilateral COM with TM perforation. Initial pure-tone audiometry (PTA) and VEMP responses were recorded. After paper patching, PTA and VEMP were re-performed. Each VEMP response was compared with those of the healthy controls. Moreover, VEMP responses between pre- and post-paper patching were compared. There was a positive correlation between normalizing of VEMP parameters, such as p13 and VEMP asymmetry ratio (VAR), and reduction of air-bone gap in patients with COM after paper patching. The VEMP response in patients with COM with intact ossicle and clean mucosa was more normalized compared with those in patients with COM with different middle ear conditions.

Compensating for ear-canal acoustics when measuring otoacoustic emissions

PubMed Central

Charaziak, Karolina K.; Shera, Christopher A.

2017-01-01

Otoacoustic emissions (OAEs) provide an acoustic fingerprint of the inner ear, and changes in this fingerprint may indicate changes in cochlear function arising from efferent modulation, aging, noise trauma, and/or exposure to harmful agents. However, the reproducibility and diagnostic power of OAE measurements is compromised by the variable acoustics of the ear canal, in particular, by multiple reflections and the emergence of standing waves at relevant frequencies. Even when stimulus levels are controlled using methods that circumvent standing-wave problems (e.g., forward-pressure-level calibration), distortion-product otoacoustic emission (DPOAE) levels vary with probe location by 10–15 dB near half-wave resonant frequencies. The method presented here estimates the initial outgoing OAE pressure wave at the eardrum from measurements of the conventional OAE, allowing one to separate the emitted OAE from the many reflections trapped in the ear canal. The emitted pressure level (EPL) represents the OAE level that would be recorded were the ear canal replaced by an infinite tube with no reflections. When DPOAEs are expressed using EPL, their variation with probe location decreases to the test–retest repeatability of measurements obtained at similar probe positions. EPL provides a powerful way to reduce the variability of OAE measurements and improve their ability to detect cochlear changes. PMID:28147590

The effects of alterations in the osseous external auditory canal on perceived sound quality.

PubMed

van Spronsen, Erik; Brienesse, Patrick; Ebbens, Fenna A; Waterval, Jerome J; Dreschler, Wouter A

2015-10-01

To evaluate the perceptual effect of the altered shape of the osseous external auditory canal (OEAC) on sound quality. Prospective study. Twenty subjects with normal hearing were presented with six simulated sound conditions representing the acoustic properties of six different ear canals (three normal ears and three cavities). The six different real ear unaided responses of these ear canals were used to filter Dutch sentences, resulting in six simulated sound conditions. A seventh unfiltered reference condition was used for comparison. Sound quality was evaluated using paired comparison ratings and a visual analog scale (VAS). Significant differences in sound quality were found between the normal and cavity conditions (all P < .001) using both the seven-point paired comparison rating and the VAS. No significant differences were found between the reference and normal conditions. Sound quality deteriorates when the OEAC is altered into a cavity. This proof of concept study shows that the altered acoustic quality of the OEAC after radical cavity surgery may lead to a clearly perceived deterioration in sound quality. Nevertheless, some questions remain about the extent to which these changes are affected by habituation and by other changes in middle ear anatomy and functionality. 4 © 2015 The American Laryngological, Rhinological and Otological Society, Inc.

Fitting and verification of frequency modulation systems on children with normal hearing.

PubMed

Schafer, Erin C; Bryant, Danielle; Sanders, Katie; Baldus, Nicole; Algier, Katherine; Lewis, Audrey; Traber, Jordan; Layden, Paige; Amin, Aneeqa

2014-06-01

Several recent investigations support the use of frequency modulation (FM) systems in children with normal hearing and auditory processing or listening disorders such as those diagnosed with auditory processing disorders, autism spectrum disorders, attention-deficit hyperactivity disorder, Friedreich ataxia, and dyslexia. The American Academy of Audiology (AAA) published suggested procedures, but these guidelines do not cite research evidence to support the validity of the recommended procedures for fitting and verifying nonoccluding open-ear FM systems on children with normal hearing. Documenting the validity of these fitting procedures is critical to maximize the potential FM-system benefit in the above-mentioned populations of children with normal hearing and those with auditory-listening problems. The primary goal of this investigation was to determine the validity of the AAA real-ear approach to fitting FM systems on children with normal hearing. The secondary goal of this study was to examine speech-recognition performance in noise and loudness ratings without and with FM systems in children with normal hearing sensitivity. A two-group, cross-sectional design was used in the present study. Twenty-six typically functioning children, ages 5-12 yr, with normal hearing sensitivity participated in the study. Participants used a nonoccluding open-ear FM receiver during laboratory-based testing. Participants completed three laboratory tests: (1) real-ear measures, (2) speech recognition performance in noise, and (3) loudness ratings. Four real-ear measures were conducted to (1) verify that measured output met prescribed-gain targets across the 1000-4000 Hz frequency range for speech stimuli, (2) confirm that the FM-receiver volume did not exceed predicted uncomfortable loudness levels, and (3 and 4) measure changes to the real-ear unaided response when placing the FM receiver in the child's ear. After completion of the fitting, speech recognition in noise at a -5 signal-to-noise ratio and loudness ratings at a +5 signal-to-noise ratio were measured in four conditions: (1) no FM system, (2) FM receiver on the right ear, (3) FM receiver on the left ear, and (4) bilateral FM system. The results of this study suggested that the slightly modified AAA real-ear measurement procedures resulted in a valid fitting of one FM system on children with normal hearing. On average, prescriptive targets were met for 1000, 2000, 3000, and 4000 Hz within 3 dB, and maximum output of the FM system never exceeded and was significantly lower than predicted uncomfortable loudness levels for the children. There was a minimal change in the real-ear unaided response when the open-ear FM receiver was placed into the ear. Use of the FM system on one or both ears resulted in significantly better speech recognition in noise relative to a no-FM condition, and the unilateral and bilateral FM receivers resulted in a comfortably loud signal when listening in background noise. Real-ear measures are critical for obtaining an appropriate fit of an FM system on children with normal hearing. American Academy of Audiology.

Effect of cotton bollworm (Helicoverpa armigera Hübner) caused injury on maize grain content, especially regarding to the protein alteration.

PubMed

Keszthelyi, S; Pál-Fám, F; Kerepesi, I

2011-03-01

The cotton bollworm (Helicoverpa armigera Hübner), which migrated in the Carpathian-basin from Mediterraneum in the last decades, is becoming an increasingly serious problem for maize producers in Hungary. In several regions the damage it causes has reached the threshold of economic loss, especially in the case of the sweet maize cultivation. The aim of the research was to determine the changing of ears weights and in-kernel accumulation and alteration in grain as a function of cotton bollworm mastication.Our investigation confirmed that there is an in-kernel and protein pattern change of maize grain by cotton bollworm. Our results proved the significant damaging of each part of ears by cotton bollworm masticating (the average weight loss of ears: 13.99%; the average weight loss of grains: 14.03%; the average weight loss of cobs: 13.74%), with the exception of the increasing of the grain-cob ratio. Our examinations did not prove the water loss - that is the "forced maturing" - caused by the damage. Decreasing of raw fat (control: 2.8%; part-damaged: 2.6%; damaged: 2.4%) and starch content (control: 53.1%; part-damaged: 46.6%; damaged: 44.7%) were registered as a function of injury. In contrast, the raw protein content was increased (control: 4.7%; part-damaged: 5.3%; damaged: 7.4%) by maize ear masticating. The most conspicuous effect on protein composition changing was proved by comparison of damaged grain samples by SDS PAGE. Increased amounts of 114, 50, 46 and 35 kDa molecular mass proteins were detected which explained the more than 50% elevation of raw protein content. The statistical analysis of molecular weights proved the protein realignment as a function of the pest injuries, too.

Monaural and binaural contributions to interaural-level-difference sensitivity in human auditory cortex.

PubMed

Stecker, G Christopher; McLaughlin, Susan A; Higgins, Nathan C

2015-10-15

Whole-brain functional magnetic resonance imaging was used to measure blood-oxygenation-level-dependent (BOLD) responses in human auditory cortex (AC) to sounds with intensity varying independently in the left and right ears. Echoplanar images were acquired at 3 Tesla with sparse image acquisition once per 12-second block of sound stimulation. Combinations of binaural intensity and stimulus presentation rate were varied between blocks, and selected to allow measurement of response-intensity functions in three configurations: monaural 55-85 dB SPL, binaural 55-85 dB SPL with intensity equal in both ears, and binaural with average binaural level of 70 dB SPL and interaural level differences (ILD) ranging ±30 dB (i.e., favoring the left or right ear). Comparison of response functions equated for contralateral intensity revealed that BOLD-response magnitudes (1) generally increased with contralateral intensity, consistent with positive drive of the BOLD response by the contralateral ear, (2) were larger for contralateral monaural stimulation than for binaural stimulation, consistent with negative effects (e.g., inhibition) of ipsilateral input, which were strongest in the left hemisphere, and (3) also increased with ipsilateral intensity when contralateral input was weak, consistent with additional, positive, effects of ipsilateral stimulation. Hemispheric asymmetries in the spatial extent and overall magnitude of BOLD responses were generally consistent with previous studies demonstrating greater bilaterality of responses in the right hemisphere and stricter contralaterality in the left hemisphere. Finally, comparison of responses to fast (40/s) and slow (5/s) stimulus presentation rates revealed significant rate-dependent adaptation of the BOLD response that varied across ILD values. Copyright © 2015. Published by Elsevier Inc.

[Investigation of tympanogram in newborns with 226 hz and 1000 hz probe tones].

PubMed

Li, Mengyin; Zheng, Yun; Li, Gang; Wang, Kai

2012-11-01

This study aims at investigating tympanogram in newborns who passed hearing screening using 226 and 1 000 Hz probe tones in order to interpret the test results correctly and find out its clinical value in audiological evaluation and diagnosis in this population. Tympanogram was conducted using 226 and 1000 Hz probe tones in 206 newborns between 2 and 7 days of age (3.92 +/- 1.24) in both ears that passed the DPOAE screening and without any of the high risk register (HRR) factors associated with hearing loss according to the Joint Committee on Infant Hearing in 2007. The tympanogram results tested in 408 ear were as following: the percentage of single-peaked, double-peaked, and none-peaked tympanograms using 226 Hz were 52.20% (213 ears), 47.55% (194 ears) and 0.25% (1 ear) respectively. The percentage of single-peaked and other morphological type tympanograms using 1000 Hz were 94.85%(387 ears) and 5.15% (21 ears) respectively. The parameters of 1000 Hz single-peaked tympanogram in this study were as following: the average tympanometric peak pressure was 33.24 +/- 44.37 dapa, the average peak compensated static acoustic admittance was 0.52 +/- 0.25 mmho, the average tympanometric width for right and left ears were 121.38 +/- 28.79 and 108.63 +/- 26.00 dapa respectively with a statistically significant difference between them (P < 0.01). The average volume of ear canal (Vec, using 226 Hz probe tone) at boys and girls were 0.44 +/- 0.10 and 0.43 +/- 0.08 ml respectively with a statistically significant difference between them (P < 0.05). The morphology of tympanogram using a 226 Hz probe tone in newborns usually includes two main types: single-peaked and double-peaked, while it is primarily the single-peaked tympanogram while using a 1000 Hz probe tone. It is more appropriate to use a 1000 Hz probe tone than 226 Hz when testing newborns' tympanogram. The parameters obtained in this study using 1000 Hz and 226 Hz could be tried and applied to interpret clinical tympanogram test results and evaluate middle ear function. However, more studies with bigger sample size are necessary in this field.

Dichotic listening in patients with situs inversus: brain asymmetry and situs asymmetry.

PubMed

Tanaka, S; Kanzaki, R; Yoshibayashi, M; Kamiya, T; Sugishita, M

1999-06-01

In order to investigate the relation between situs asymmetry and functional asymmetry of the human brain, a consonant-vowel syllable dichotic listening test known as the Standard Dichotic Listening Test (SDLT) was administered to nine subjects with situs inversus (SI) that ranged in age from 6 to 46 years old (mean of 21.8 years old, S.D. = 15.6); the four males and five females all exhibited strong right-handedness. The SDLT was also used to study twenty four age-matched normal subjects that were from 6 to 48 years old (mean 21.7 years old, S.D. = 15.3); the twelve males and twelve females were all strongly right-handed and served as a control group. Eight out of the nine subjects (88.9%) with SI more often reproduced the sounds from the right ear than sounds from the left ear; this is called right ear advantage (REA). The ratio of REA in the control group was almost the same, i.e., nineteen out of the twenty-four subjects (79.1%) showed REA. Results of the present study suggest that the left-right reversal in situs inversus does not involve functional asymmetry of the brain. As such, the system that produces functional asymmetry in the human brain must independently recognize laterality from situs asymmetry.

Comparison of the benefits of cochlear implantation versus contra-lateral routing of signal hearing aids in adult patients with single-sided deafness: study protocol for a prospective within-subject longitudinal trial

PubMed Central

2014-01-01

Background Individuals with a unilateral severe-to-profound hearing loss, or single-sided deafness, report difficulty with listening in many everyday situations despite having access to well-preserved acoustic hearing in one ear. The standard of care for single-sided deafness available on the UK National Health Service is a contra-lateral routing of signals hearing aid which transfers sounds from the impaired ear to the non-impaired ear. This hearing aid has been found to improve speech understanding in noise when the signal-to-noise ratio is more favourable at the impaired ear than the non-impaired ear. However, the indiscriminate routing of signals to a single ear can have detrimental effects when interfering sounds are located on the side of the impaired ear. Recent published evidence has suggested that cochlear implantation in individuals with a single-sided deafness can restore access to the binaural cues which underpin the ability to localise sounds and segregate speech from other interfering sounds. Methods/Design The current trial was designed to assess the efficacy of cochlear implantation compared to a contra-lateral routing of signals hearing aid in restoring binaural hearing in adults with acquired single-sided deafness. Patients are assessed at baseline and after receiving a contra-lateral routing of signals hearing aid. A cochlear implant is then provided to those patients who do not receive sufficient benefit from the hearing aid. This within-subject longitudinal design reflects the expected care pathway should cochlear implantation be provided for single-sided deafness on the UK National Health Service. The primary endpoints are measures of binaural hearing at baseline, after provision of a contra-lateral routing of signals hearing aid, and after cochlear implantation. Binaural hearing is assessed in terms of the accuracy with which sounds are localised and speech is perceived in background noise. The trial is also designed to measure the impact of the interventions on hearing- and health-related quality of life. Discussion This multi-centre trial was designed to provide evidence for the efficacy of cochlear implantation compared to the contra-lateral routing of signals. A purpose-built sound presentation system and established measurement techniques will provide reliable and precise measures of binaural hearing. Trial registration Current Controlled Trials http://www.controlled-trials.com/ISRCTN33301739 (05/JUL/2013) PMID:25152694

Modified suture-bridge technique to prevent a marginal dog-ear deformity improves structural integrity after rotator cuff repair.

PubMed

Ryu, Keun Jung; Kim, Bang Hyun; Lee, Yohan; Lee, Yoon Seok; Kim, Jae Hwa

2015-03-01

The arthroscopic suture-bridge technique has proved to provide biomechanically firm fixation of the torn rotator cuff to the tuberosity by increasing the footprint contact area and pressure. However, a marginal dog-ear deformity is encountered not infrequently when this technique is used, impeding full restoration of the torn cuff. To evaluate the structural and functional outcomes of the use of a modified suture-bridge technique to prevent a marginal dog-ear deformity compared with a conventional suture-bridge method in rotator cuff repair. Cohort study; Level of evidence 2. A consecutive series of 71 patients aged 50 to 65 years who underwent arthroscopic rotator cuff repair for full-thickness medium-sized to massive tears was evaluated. Patients were divided into 2 groups according to repair technique: a conventional suture-bridge technique (34 patients; group A) versus a modified suture-bridge technique to prevent a marginal dog-ear deformity (37 patients; group B). Radiographic evaluations included postoperative cuff integrity using MRI. Functional evaluations included pre- and postoperative range of motion (ROM), pain visual analog scale (VAS), the University of California, Los Angeles (UCLA) shoulder rating scale, the Constant score, and the American Shoulder and Elbow Surgeons (ASES) score. All patients were followed up clinically at a minimum of 1 year. When the 2 surgical techniques were compared, postoperative structural integrity by Sugaya classification showed the distribution of types I:II:III:IV:V to be 4:20:2:4:4 in group A and 20:12:4:0:1 in group B. More subjects in group B had a favorable Sugaya type compared with group A (P < .001). The postoperative healed:retear rate was 26:8 in group A and 36:1 in group B, with a significantly lower retear rate in group B (P = .011). However, there were no significant differences in ROM and all functional outcome scores between the 2 groups postoperatively. When surgical techniques were compared across healed (n = 62) and retear (n = 9) groups, significantly fewer modified suture-bridge technique repairs were found in the retear group (P = .03). There were significant differences between healed and retear groups in functional outcome scores, with worse results in the retear group. A modified suture-bridge technique to prevent a marginal dog-ear deformity provided better structural outcomes than a conventional suture-bridge technique for medium-sized to massive rotator cuff tears. This technique may ultimately provide better functional outcomes by decreasing the retear rate. © 2014 The Author(s).

Comparative inner ear transcriptome analysis between the Rickett's big-footed bats (Myotis ricketti) and the greater short-nosed fruit bats (Cynopterus sphinx).

PubMed

Dong, Dong; Lei, Ming; Liu, Yang; Zhang, Shuyi

2013-12-23

Bats have aroused great interests of researchers for the sake of their advanced echolocation system. However, this highly specialized trait is not characteristic of Old World fruit bats. To comprehensively explore the underlying molecular basis between echolocating and non-echolocating bats, we employed a sequence-based approach to compare the inner ear expression difference between the Rickett's big-footed bat (Myotis ricketti, echolocating bat) and the Greater short-nosed fruit bat (Cynopterus sphinx, non-echolocating bat). De novo sequence assemblies were developed for both species. The results showed that the biological implications of up-regulated genes in M. ricketti were significantly over-represented in biological process categories such as 'cochlea morphogenesis', 'inner ear morphogenesis' and 'sensory perception of sound', which are consistent with the inner ear morphological and physiological differentiation between the two bat species. Moreover, the expression of TMC1 gene confirmed its important function in echolocating bats. Our work presents the first transcriptome comparison between echolocating and non-echolocating bats, and provides information about the genetic basis of their distinct hearing traits.

Whole-mount Confocal Microscopy for Adult Ear Skin: A Model System to Study Neuro-vascular Branching Morphogenesis and Immune Cell Distribution.

PubMed

Yamazaki, Tomoko; Li, Wenling; Mukouyama, Yoh-Suke

2018-03-29

Here, we present a protocol of a whole-mount adult ear skin imaging technique to study comprehensive three-dimensional neuro-vascular branching morphogenesis and patterning, as well as immune cell distribution at a cellular level. The analysis of peripheral nerve and blood vessel anatomical structures in adult tissues provides some insights into the understanding of functional neuro-vascular wiring and neuro-vascular degeneration in pathological conditions such as wound healing. As a highly informative model system, we have focused our studies on adult ear skin, which is readily accessible for dissection. Our simple and reproducible protocol provides an accurate depiction of the cellular components in the entire skin, such as peripheral nerves (sensory axons, sympathetic axons, and Schwann cells), blood vessels (endothelial cells and vascular smooth muscle cells), and inflammatory cells. We believe this protocol will pave the way to investigate morphological abnormalities in peripheral nerves and blood vessels as well as the inflammation in the adult ear skin under different pathological conditions.

Signatures from Tissue-specific MPSS Libraries Identify Transcripts Preferentially Expressed in the Mouse Inner Ear

PubMed Central

Peters, Linda M.; Belyantseva, Inna A.; Lagziel, Ayala; Battey, James F.; Friedman, Thomas B.; Morell, Robert J.

2007-01-01

Specialization in cell function and morphology is influenced by the differential expression of mRNAs, many of which are expressed at low abundance and restricted to certain cell types. Detecting such transcripts in cDNA libraries may require sequencing millions of clones. Massively parallel signature sequencing (MPSS) is well-suited for identifying transcripts that are expressed in discrete cell types and in low abundance. We have made MPSS libraries from microdissections of three inner ear tissues. By comparing these MPSS libraries to those of 87 other tissues included in the Mouse Reference Transcriptome (MRT) online resource, we have identified genes that are highly enriched in, or specific to, the inner ear. We show by RT-PCR and in situ hybridization that signatures unique to the inner ear libraries identify transcripts with highly specific cell-type localizations. These transcripts serve to illustrate the utility of a resource that is available to the research community. Utilization of these resources will increase the number of known transcription units and expand our knowledge of the tissue-specific regulation of the transcriptome. PMID:17049805

Application of the Vibrant Soundbridge middle-ear implant for aural atresia in patients with Treacher Collins syndrome.

PubMed

Lesinskas, E; Stankeviciute, V; Petrulionis, M

2012-12-01

To present results for the auditory rehabilitation of patients with Treacher Collins syndrome with bilateral osseous atresia, using middle-ear implantation with a Vibrant Soundbridge. Three patients underwent vibroplasty for aural atresia with moderate to severe conductive hearing loss. The pre-operative Jahrsdoerfer radiological score was 4 for all patients. Patients underwent active middle-ear implantation of a Vibrant Soundbridge implant (coupling the floating mass transducer to the rudimentary stapes or footplate distally, and positioning it adjacent to the round window membrane proximally), with audiological analysis as follow up. After implant activation, the mean air conduction threshold ± standard deviation decreased to 22.8 ± 5.5 dB HL, representing a mean functional gain of 44.5 dB. The mean word recognition score (for bisyllabic words at 65 dB SPL) increased from 0 to 97 per cent. Vibrant Soundbridge implantation is an effective hearing rehabilitation procedure in patients with Treacher Collins syndrome with bilateral osseous atresia. This is a versatile implant which can achieve coupling even in cases of severe middle-ear malformation.

Use of a highly transparent zebrafish mutant for investigations in the development of the vertebrate auditory system (Conference Presentation)

NASA Astrophysics Data System (ADS)

Wisniowiecki, Anna M.; Mattison, Scott P.; Kim, Sangmin; Riley, Bruce; Applegate, Brian E.

2016-03-01

Zebrafish, an auditory specialist among fish, offer analogous auditory structures to vertebrates and is a model for hearing and deafness in vertebrates, including humans. Nevertheless, many questions remain on the basic mechanics of the auditory pathway. Phase-sensitive Optical Coherence Tomography has been proven as valuable technique for functional vibrometric measurements in the murine ear. Such measurements are key to building a complete understanding of auditory mechanics. The application of such techniques in the zebrafish is impeded by the high level of pigmentation, which develops superior to the transverse plane and envelops the auditory system superficially. A zebrafish double mutant for nacre and roy (mitfa-/- ;roya-/- [casper]), which exhibits defects for neural-crest derived melanocytes and iridophores, at all stages of development, is pursued to improve image quality and sensitivity for functional imaging. So far our investigations with the casper mutants have enabled the identification of the specialized hearing organs, fluid-filled canal connecting the ears, and sub-structures of the semicircular canals. In our previous work with wild-type zebrafish, we were only able to identify and observe stimulated vibration of the largest structures, specifically the anterior swim bladder and tripus ossicle, even among small, larval specimen, with fully developed inner ears. In conclusion, this genetic mutant will enable the study of the dynamics of the zebrafish ear from the early larval stages all the way into adulthood.

Engineering Data Compendium. Human Perception and Performance. Volume 3

DTIC Science & Technology

1988-01-01

Wagener, & G. E. Herman. Binaural analysis in the aging auditory system. 1978, 33. 8.316, Fig. I: From K. D. Kryter, Effects of ear protective...Amplitude distortion, 8.313 Articulation index. 8.317 Articulatory features, 8.205 Aspiration, 8.207 Attention, divided, 8.120 Binaural unmasking, 8.312...8.125-8.128 Transfer of training. 8.120 Unmasking, binaural , 8.312, 8.314, 8.315 Verbal memory. 8.101 Verbal recall. 8.311 Visual field location

On the influence of altered gravity on the growth of fish inner ear otoliths

NASA Astrophysics Data System (ADS)

Beier, Marion

1999-09-01

Inner ear stones (otoliths) of developing cichlid fish ( Oreochromis mossambicus) were marked with the calcium tracer alizarin-complexone (AC) at 1g-earth gravity before and after a long-term (20 days) stay of the animals at moderate hypergravity conditions (3g; centrifuge). AC deposition at the otoliths resulted in two fluorescence bands, which enclosed the area grown during exposure to altered gravity. This area was measured with regard to size and asymmetry (size difference between the left and the right stones). Both utricular and saccular otoliths (lapilli and sagittae, respectively) were significantly smaller after hyper-g exposure as compared to parallely raised 1g-control specimens. The asymmetry concerning the lapilli was pronouncedly decreased in comparison to the 1g-controls. These findings suggest, that the growth and the development of bilateral asymmetry of otoliths is guided by the environmental gravity vector. Some of the hyper-g animals revealed a kinetotic behaviour at the transfer from hyper-g to normal 1g-earth gravity conditions, which was qualitatively similar to the behaviour observed in previous experiments at the transfer from 1g to microgravity in the course of parabolic aircraft flights. The lapillar asymmetry of kinetotic samples was found to be significantly higher than that of normally behaving experimental specimens. This result supports an earlier theoretical concept, according to which human static space sickness might be based on asymmetric utricular otoliths.

Ebselen is a new skin depigmenting agent that inhibits melanin biosynthesis and melanosomal transfer.

PubMed

Kasraee, Behrooz; Nikolic, Damjan S; Salomon, Denis; Carraux, Pierre; Fontao, Lionel; Piguet, Vincent; Omrani, Gholamhossein R; Sorg, Olivier; Saurat, Jean-Hilaire

2012-01-01

We assessed the ability of ebselen, a glutathione peroxidase mimic, to reduce pigmentation in various models. In murine B16 melanocytes, 25 μm ebselen inhibited melanogenesis and induced a depolymerisation of actin filaments. In co-cultures of B16 melanocytes with BDVII keratinocytes, a pretreatment of melanocytes with ebselen resulted in a strong inhibition of melanosome transfer to keratinocytes, as shown under optical and electron microscopy. In reconstructed epidermis, topical 0.5% ebselen led to a twofold decrease of melanin without affecting the density of active melanocytes. A similar result was obtained with topical 0.5% ebselen in black guinea pig ears. Ebselen induced a decrease of epidermal melanin parallel to a localisation of melanin and melanosomes in the basal layer. Ebselen appears as a new depigmenting compound that inhibits melanin synthesis and melanosome transfer to keratinocytes. © 2011 John Wiley & Sons A/S.

Effectiveness of Ear Splint Therapy for Ear Deformities

PubMed Central

2017-01-01

Objective To present our experience with ear splint therapy for babies with ear deformities, and thereby demonstrate that this therapy is an effective and safe intervention without significant complications. Methods This was a retrospective study of 54 babies (35 boys and 19 girls; 80 ears; age ≤3 months) with ear deformities who had received ear splint therapy at the Center for Torticollis, Department of Physical Medicine and Rehabilitation, Ajou University Hospital between December 2014 and February 2016. Before the initiation of ear splint therapy, ear deformities were classified with reference to the standard terminology. We compared the severity of ear deformity before and after ear splint therapy by using the physician's ratings. We also compared the physician's ratings and the caregiver's ratings on completion of ear splint therapy. Results Among these 54 babies, 41 children (58 ears, 72.5%) completed the ear splint therapy. The mean age at initiation of therapy was 52.91±18.26 days and the treatment duration was 44.27±32.06 days. Satyr ear, forward-facing ear lobe, Darwinian notch, overfolded ear, and cupped ear were the five most common ear deformities. At the completion of therapy, the final physician's ratings of ear deformities were significantly improved compared to the initial ratings (8.28±1.44 vs. 2.51±0.92; p<0.001). There was no significant difference between the physician's ratings and the caregiver's ratings at the completion of ear splint therapy (8.28±1.44 vs. 8.0±1.61; p=0.297). Conclusion We demonstrated that ear splint therapy significantly improved ear deformities in babies, as measured by quantitative rating scales. Ear splint therapy is an effective and safe intervention for babies with ear deformities. PMID:28289646

Gentamicin alters Akt-expression and its activation in the guinea pig cochlea.

PubMed

Heinrich, U-R; Strieth, S; Schmidtmann, I; Li, H; Helling, K

2015-12-17

Gentamicin treatment induces hair cell death or survival in the inner ear. Besides the well-known toxic effects, the phosphatidylinositol-3 kinase/Akt (PI3K/Akt) pathway was found to be involved in cell protection. After gentamicin application, the spatiotemporal expression patterns of Akt and its activated form (p-Akt) were determined in male guinea pigs. A single dose of 0.1 mL gentamicin (4 mg/ear/animal) was intratympanically injected. The auditory brainstem responses (ABRs) were recorded prior to application and 1, 2 and 7 days afterward. At these three time points the cochleae (n=10 in each case) were removed, transferred to fixative and embedded in paraffin. Seven ears were used as untreated controls. Gentamicin, Akt and p-Akt were identified immunohistochemically in various regions of the cochlea and their staining intensities were quantified on sections using digital image analysis. The application of gentamicin resulted in hearing loss with a concomitant up-regulation of Akt-expression in the organ of Corti and spiral ganglion cells and an additional activation in spiral ganglion cells. At the level of individual ears, clear intracellular correlations were found between Akt- and p-Akt-expression in the stria vascularis and interdental cells and, to a minor extent, in the spiral ligament and the organ of Corti. Furthermore, statistical evidence for the connection between gentamicin up-take and hearing loss was detected. The increase in Akt- and p-Akt-expression in the organ of Corti and spiral ganglion cells indicates a selected response of the cochlea against gentamicin toxicity. Copyright © 2015 IBRO. Published by Elsevier Ltd. All rights reserved.

Biotin status affects nickel allergy via regulation of interleukin-1beta production in mice.

PubMed

Kuroishi, Toshinobu; Kinbara, Masayuki; Sato, Naoki; Tanaka, Yukinori; Nagai, Yasuhiro; Iwakura, Yoichiro; Endo, Yasuo; Sugawara, Shunji

2009-05-01

Biotin, a water-soluble B complex vitamin, is possibly involved in chronic inflammatory diseases, although the detailed mechanisms are unclear. In this study, we investigated the effects of biotin status on nickel (Ni) allergy in mice. Mice were fed a basal or biotin-deficient (BD) diet for 8 wk and sensitized with an intraperitoneal injection of NiCl(2) and lipopolysaccharide. Ten days after sensitization, NiCl(2) was intradermally injected into pinnas and ear swelling was measured. For in vitro analysis, we cultured a murine macrophage cell line, J774.1, under a biotin-sufficient (C, meaning control) or BD condition for 4 wk and analyzed interleukin (IL)-1 production. Significantly higher ear swelling was induced in BD mice than C mice. Adaptive transfer of splenocytes from both C and BD mice induced Ni allergy in unsensitized mice. Regardless of donor mice, ear swelling was significantly higher in BD recipient mice than C recipient mice. Ni allergy was not induced in either C or BD IL-1(-/-) mice. Splenocytes from BD mice produced a significantly higher amount of IL-1beta than those from C mice. Production and mRNA expression of IL-1beta were significantly higher in BD J774.1 cells than in C cells. Biotin supplementation inhibited the augmentation of IL-1beta production in vitro. In vivo supplementation of biotin in drinking water dose-dependently decreased ear swelling in C and BD mice. These results indicate that biotin status affects Ni allergy in the elicitation phase via the upregulation of IL-1beta production in mice, suggesting that biotin supplementation may have therapeutic effects on human metal allergy.

Plant uptake of elements in soil and pore water: field observations versus model assumptions.

PubMed

Raguž, Veronika; Jarsjö, Jerker; Grolander, Sara; Lindborg, Regina; Avila, Rodolfo

2013-09-15

Contaminant concentrations in various edible plant parts transfer hazardous substances from polluted areas to animals and humans. Thus, the accurate prediction of plant uptake of elements is of significant importance. The processes involved contain many interacting factors and are, as such, complex. In contrast, the most common way to currently quantify element transfer from soils into plants is relatively simple, using an empirical soil-to-plant transfer factor (TF). This practice is based on theoretical assumptions that have been previously shown to not generally be valid. Using field data on concentrations of 61 basic elements in spring barley, soil and pore water at four agricultural sites in mid-eastern Sweden, we quantify element-specific TFs. Our aim is to investigate to which extent observed element-specific uptake is consistent with TF model assumptions and to which extent TF's can be used to predict observed differences in concentrations between different plant parts (root, stem and ear). Results show that for most elements, plant-ear concentrations are not linearly related to bulk soil concentrations, which is congruent with previous studies. This behaviour violates a basic TF model assumption of linearity. However, substantially better linear correlations are found when weighted average element concentrations in whole plants are used for TF estimation. The highest number of linearly-behaving elements was found when relating average plant concentrations to soil pore-water concentrations. In contrast to other elements, essential elements (micronutrients and macronutrients) exhibited relatively small differences in concentration between different plant parts. Generally, the TF model was shown to work reasonably well for micronutrients, whereas it did not for macronutrients. The results also suggest that plant uptake of elements from sources other than the soil compartment (e.g. from air) may be non-negligible. Copyright © 2013 Elsevier Ltd. All rights reserved.

Multiple host defense defects in failure of C57BL/6 ep/ep (pale ear) mice to resolve visceral Leishmania donovani infection.

PubMed Central

Murray, H W; Hariprashad, J; McDermott, D F; Stoeckle, M Y

1996-01-01

Euthymic C57BL/L ep/ep (pale ear [PE]) mice halt the visceral replication of intracellular Leishmania donovani but fail to properly resolve infection. A previous study identified an isolated defect in tissue granuloma formation in these mice; CD4+ and CD8+ cell number, gamma interferon (IFN-gamma) production, and macrophage antimicrobial activity in vitro were all intact. New in vivo results reported here suggest a considerably more complex immune defect, with evidence indicating (i) enhanced control over L. donovani after transfer of normal C57BL/6 spleen cells, (ii) a partially suppressive Th2 cell-associated response mediated by interleukin-4 (IL-4) but not reversed by CD4+ cell depletion, (iii) absent responses to endogenous Th1 cell lymphokines (IFN-gamma and IL-2) but preserved responsiveness to endogenous tumor necrosis factor alpha, (iv) absent responses to exogenous treatment with recognized antileishmanial cytokines (IFN-gamma, IL-2, IL-12, and granulocyte-macrophage colony-stimulating factor [GM-CSF]) not corrected by transfer of C57BL/6 spleen cells, and (v) a deficient response to antimony chemotherapy. Defective hepatic granuloma formation was not corrected by transfer of C57BL/6 spleen cells or by anti-IL-4 administration. While treatment with IL-2 and GM-CSF modified the tissue reaction and induced selected effector cells to encase tissue macrophages, no antileishmanial activity resulted. Together, these observations suggest that the failure of PE mice to resolve visceral L. donovani infection likely represents expression of multiple suboptimal immune responses and/or partial defects, probably involving a combination of T-cell dysfunction, a Th2 cell response, and target cell (macrophage) hyporesponsiveness. PMID:8557335

Contralateral Masking in Bilateral Cochlear Implant Patients: A Model of Medial Olivocochlear Function Loss

PubMed Central

Aronoff, Justin M.; Padilla, Monica; Fu, Qian-Jie; Landsberger, David M.

2015-01-01

Contralateral masking is the phenomenon where a masker presented to one ear affects the ability to detect a signal in the opposite ear. For normal hearing listeners, contralateral masking results in masking patterns that are both sharper and dramatically smaller in magnitude than ipsilateral masking. The goal of this study was to investigate whether medial olivocochlear (MOC) efferents are needed for the sharpness and relatively small magnitude of the contralateral masking function. To do this, bilateral cochlear implant patients were tested because, by directly stimulating the auditory nerve, cochlear implants circumvent the effects of the MOC efferents. The results indicated that, as with normal hearing listeners, the contralateral masking function was sharper than the ipsilateral masking function. However, although there was a reduction in the magnitude of the contralateral masking function compared to the ipsilateral masking function, it was relatively modest. This is in sharp contrast to the results of normal hearing listeners where the magnitude of the contralateral masking function is greatly reduced. These results suggest that MOC function may not play a large role in the sharpness of the contralateral masking function but may play a considerable role in the magnitude of the contralateral masking function. PMID:25798581

Nasal Allergy and Otitis Media

PubMed Central

Passali, Desiderio; Passali, Giulio C.; Lauriello, Maria; Romano, Antonio; Bellussi, Luisa; Passali, Francesco M.

2014-01-01

Objectives: The correlation between middle ear pathology and nasal allergy has been debated for almost 30 years. This study aimed to evaluate the relationship between otitis media with effusion (OME) and persistent allergic rhinitis symptoms versus intermittent rhinitis in children. Methods: The study included 100 atopic children (52 boys, 48 girls) aged 5–9 years with otological symptoms who were patients of the University of Siena Hospital, Italy. Ear, nose and throat evaluations, tympanometry, skin prick tests (SPTs), mucociliary transport time (MCTt) and Eustachian tube function tests were performed. Results: The SPTs revealed 50 children sensitised to Dermatophagoides pteronyssinus, 34 to grass pollen and 16 to Parietaria. Of all patients, mild symptoms were intermittent in 19 children and persistent in 18; moderate/severe symptoms were intermittent in 22 and persistent in 41. Tubal dysfunction was present in 25 children, whereas middle ear effusion was present in 45 children undergoing myringotomy. The MCTt was slower in the persistent group (21 ± 2 mins) versus the intermittent group (16 ± 2 mins) with a significant difference (P <0.01). Mean eosinophil cationic protein (ECP) values in the middle ear effusions of children who had undergone myringotomy were 251 ± 175.2 μg/L, and mean ECP blood values were 25.5 ± 16.3 μg/L, with significant differences (P < 0.001). Conclusion: There was a significant association between OME, delayed MCTt, ECP values in middle ear effusion and persistent symptoms of allergic rhinitis. These results suggest a direct involvement of the middle ear mucosa as a target organ in persistent forms. PMID:24516755

Improving Measurement Efficiency of the Inner EAR Scale with Item Response Theory.

PubMed

Jessen, Annika; Ho, Andrew D; Corrales, C Eduardo; Yueh, Bevan; Shin, Jennifer J

2018-02-01

Objectives (1) To assess the 11-item Inner Effectiveness of Auditory Rehabilitation (Inner EAR) instrument with item response theory (IRT). (2) To determine whether the underlying latent ability could also be accurately represented by a subset of the items for use in high-volume clinical scenarios. (3) To determine whether the Inner EAR instrument correlates with pure tone thresholds and word recognition scores. Design IRT evaluation of prospective cohort data. Setting Tertiary care academic ambulatory otolaryngology clinic. Subjects and Methods Modern psychometric methods, including factor analysis and IRT, were used to assess unidimensionality and item properties. Regression methods were used to assess prediction of word recognition and pure tone audiometry scores. Results The Inner EAR scale is unidimensional, and items varied in their location and information. Information parameter estimates ranged from 1.63 to 4.52, with higher values indicating more useful items. The IRT model provided a basis for identifying 2 sets of items with relatively lower information parameters. Item information functions demonstrated which items added insubstantial value over and above other items and were removed in stages, creating a 8- and 3-item Inner EAR scale for more efficient assessment. The 8-item version accurately reflected the underlying construct. All versions correlated moderately with word recognition scores and pure tone averages. Conclusion The 11-, 8-, and 3-item versions of the Inner EAR scale have strong psychometric properties, and there is correlational validity evidence for the observed scores. Modern psychometric methods can help streamline care delivery by maximizing relevant information per item administered.

Hearing screening in children with skeletal dysplasia.

PubMed

Tunkel, David E; Kerbavaz, Richard; Smith, Beth; Rose-Hardison, Danielle; Alade, Yewande; Hoover-Fong, Julie

2011-12-01

To determine the prevalence of hearing loss and abnormal tympanometry in children with skeletal dysplasia. Clinical screening program. National convention of the Little People of America. Convenience sample of volunteers aged 18 years or younger with skeletal dysplasias. Hearing screening with behavioral testing and/or otoacoustic emissions, otoscopy, and tympanometry. A failed hearing screen was defined as hearing 35 dB HL (hearing level) or greater at 1 or more tested frequencies or by a "fail" otoacoustic emissions response. Types B and C tympanograms were considered abnormal. A total of 58 children (aged ≤18 years) with skeletal dysplasia enrolled, and 56 completed hearing screening. Forty-one children had normal hearing (71%); 9 failed in 1 ear (16%); and 6 failed in both ears (10%). Forty-four children had achondroplasia, and 31 had normal hearing in both ears (71%); 8 failed hearing screening in 1 ear (18%), and 3 in both ears (7%). Tympanometry was performed in 45 children, with normal tympanograms found in 21 (47%), bilateral abnormal tympanograms in 15 (33%), and unilateral abnormal tympanograms in 9 (20%). Fourteen children with achondroplasia had normal tympanograms (42%); 11 had bilateral abnormal tympanograms (33%); and 8 had unilateral abnormal tympanograms (24%). For those children without functioning tympanostomy tubes, there was a 9.5 times greater odds of hearing loss if there was abnormal tympanometry (P = .03). Hearing loss and middle-ear disease are both highly prevalent in children with skeletal dysplasias. Abnormal tympanometry is highly associated with the presence of hearing loss, as expected in children with eustachian tube dysfunction. Hearing screening with medical intervention is recommended for these children.

A Comparative Study of Drug Delivery Methods Targeted to the Mouse Inner Ear: Bullostomy Versus Transtympanic Injection

PubMed Central

Cediel, Rafael; Celaya, Adelaida M.; Lassaletta, Luis; Varela-Nieto, Isabel; Contreras, Julio

2017-01-01

We present two minimally invasive microsurgical techniques in rodents for specific drug delivery into the middle ear so that it may reach the inner ear. The first procedure consists of perforation of the tympanic bulla, termed bullostomy; the second one is a transtympanic injection. Both emulate human clinical intratympanic procedures. Chitosan-glycerophosphate (CGP) and Ringer´s Lactate buffer (RL) were used as biocompatible vehicles for local drug delivery. CGP is a nontoxic biodegradable polymer widely used in pharmaceutical applications. It is a viscous liquid at RT but it congeals to a semi solid phase at body temperature. RL is an isotonic solution used for intravenous administrations in humans. A small volume of this vehicle is precisely placed on the Round Window (RW) niche by means of a bullostomy. A transtympanic injection fills the middle ear and allows less control but broader access to the inner ear. The safety profiles of both techniques were studied and compared by using functional and morphological tests. Hearing was evaluated by registering the Auditory Brainstem Response (ABR) before and several times after microsurgery. The cytoarchitecture and preservation level of cochlear structures were studied by conventional histological techniques in paraformaldehyde-fixed and decalcified cochlear samples. In parallel, unfixed cochlear samples were taken and immediately frozen to analyze gene expression profiles of inflammatory markers by quantitative Reverse Transcriptase Polymerase Chain Reaction (qRT-PCR). Both procedures are suitable as drug delivery methods into the mouse middle ear, although transtympanic injection proved to be less invasive compared to bullostomy. PMID:28362376

Auditory function after application of ototopical vancomycin and mupirocin solutions in a murine model.

PubMed

Rutherford, Kimberley D; Kavanagh, Katherine; Parham, Kourosh

2011-03-01

To determine whether mupirocin (440 µg/mL) and vancomycin otic drops (25 mg/mL) show evidence of ototoxicity in CBA/J mice immediately following a 7-day course of daily intratympanic (IT) injections and 1 month following treatment. Nonrandomized controlled trial. Academic hospital laboratory. Twenty CBA/J mice. Mean auditory brainstem response (ABR) thresholds increased in all drug- and saline-treated ears immediately after 7 days of IT injections but returned to baseline for most stimulus frequencies by 30 days later. This finding appeared to be correlated with the presence and subsequent resolution of tympanic membrane (TM) perforations and granulation tissue at the injection sites. Mupirocin-treated ears showed no significant difference in ABR thresholds compared to saline-treated ears. No significant differences were noted between vancomycin- and saline-treated ears, but there was a significant interaction between testing day and stimulus frequency (P < .001). Further analysis revealed that ABR thresholds at 32 kHz remained significantly elevated in vancomycin-treated mice despite the resolution of TM perforations and granulation tissue 30 days after completion of IT injections (95% confidence interval, -13.5 to -5.5, P < .01). Although IT application of mupirocin solution (440 µg/mL) caused no significant change in the ABR thresholds in a murine model, vancomycin solution (25 mg/mL) resulted in high-frequency threshold elevations in both the ear directly injected and the contralateral ear. Mupirocin solution may be beneficial in managing otitis externa and media caused by resistant pathogens. Further studies of ototopical vancomycin are needed to define parameters governing its safe use.

Thermal effects of endoscopy in a human temporal bone model: Implications for endoscopic ear surgery

PubMed Central

Kozin, Elliott D.; Lehmann, Ashton; Carter, Margaret; Hight, Ed; Cohen, Michael; Nakajima, Hideko Heidi; Lee, Daniel J.

2015-01-01

Objective Although the theoretical risk of elevated temperatures during endoscopic ear surgery has been reported previously, neither temperature change nor heat distribution associated with the endoscope has been quantified. In this study, we measure temperature changes during rigid middle ear endoscopy in a human temporal bone model and investigate whether suction can act as a significant cooling mechanism. Study Design Human temporal bone model of endoscopic middle ear surgery. Methods Fresh human temporal bones were maintained at body temperature (~36°C). Temperature fluctuations were measured as a function of 1) distance between the tip of a 3mm 0° Hopkins rod and round window membrane, and 2) intensity of the light source. Infrared imaging determined the thermal gradient. For suction, a #20 French was utilized. Results We found: 1) an endoscope maximally powered by a xenon or LED light source resulted in a rapid temperature elevation up to 46°C within 0.5–1mm from the tip of the endoscope within 30–124 seconds; 2) elevated temperatures occurred up to 8mm from the endoscope tip; and 3) temperature decreased rapidly within 20–88 seconds of turning off the light source or applying suction. Conclusion Our findings have direct implications for avoiding excessive temperature elevation in endoscopic ear surgery. We recommend: 1) using submaximal light intensity, 2) frequent repositioning of the endoscope, and 3) removing the endoscope to allow tissue cooling. Use of suction provides rapid cooling of the middle ear space and may be incorporated in the design of new instrumentation for prolonged dissection. PMID:24604692

Aural Acoustic Stapedius-Muscle Reflex Threshold Procedures to Test Human Infants and Adults.

PubMed

Keefe, Douglas H; Feeney, M Patrick; Hunter, Lisa L; Fitzpatrick, Denis F

2017-02-01

Power-based procedures are described to measure acoustic stapedius-muscle reflex threshold and supra-threshold responses in human adult and infant ears at frequencies from 0.2 to 8 kHz. The stimulus set included five clicks in which four pulsed activators were placed between each pair of clicks, with each stimulus set separated from the next by 0.79 s to allow for reflex decay. Each click response was used to detect the presence of reflex effects across frequency that were elicited by a pulsed broadband-noise or tonal activator in the ipsilateral or contralateral test ear. Acoustic reflex shifts were quantified in terms of the difference in absorbed sound power between the initial baseline click and the later four clicks in each set. Acoustic reflex shifts were measured over a 40-dB range of pulsed activators, and the acoustic reflex threshold was objectively calculated using a maximum 10 likelihood procedure. To illustrate the principles underlying these new reflex tests, reflex shifts in absorbed sound power and absorbance are presented for data acquired in an adult ear with normal hearing and in two infant ears in the initial and follow-up newborn hearing screening exams, one with normal hearing and the other with a conductive hearing loss. The use of absorbed sound power was helpful in classifying an acoustic reflex shift as present or absent. The resulting reflex tests are in use in a large study of wideband clinical diagnosis and monitoring of middle-ear and cochlear function in infant and adult ears.

Monitoring of wheat lactic acid bacteria from the field until the first step of dough fermentation.

PubMed

Alfonzo, Antonio; Miceli, Claudia; Nasca, Anna; Franciosi, Elena; Ventimiglia, Giusi; Di Gerlando, Rosalia; Tuohy, Kieran; Francesca, Nicola; Moschetti, Giancarlo; Settanni, Luca

2017-04-01

The present work was carried out to retrieve the origin of lactic acid bacteria (LAB) in sourdough. To this purpose, wheat LAB were monitored from ear harvest until the first step of fermentation for sourdough development. The influence of the geographical area and variety on LAB species/strain composition was also determined. The ears of four Triticum durum varieties (Duilio, Iride, Saragolla and Simeto) were collected from several fields located within the Palermo province (Sicily, Italy) and microbiologically investigated. In order to trace the transfer of LAB during the consecutive steps of manipulation, ears were transformed aseptically and, after threshing, milling and fermentation, samples of kernels, semolinas and doughs, respectively, were analysed. LAB were not found to dominate the microbial communities of the raw materials. In general, kernels harboured lower levels of microorganisms than ears and ears than semolinas. Several samples showing no development of LAB colonies acidified the enrichment broth suggesting the presence of LAB below the detection limit. After fermentation, LAB loads increased consistently for all doughs, reaching levels of 7.0-7.5 Log CFU/g on M17. The values of pH (5.0) and TTA (5.6 mL NaOH/10 g of dough) indicated the occurrence of the acidification process for several doughs. LAB were phenotypically and genotypically differentiated by randomly amplified polymorphic DNA (RAPD)-PCR into eight groups including 51 strains belonging to the species Lactobacillus brevis, Lactobacillus coryniformis, Lactobacillus plantarum, Lactococcus lactis, Lactococcus garvieae, Enterococcus casseliflavus, Enterococcus faecium, Leuconostoc citreum, and Pediococcus pentosaceus. Lactobacilli constituted a minority the LAB community, while lactococci represented more than 50% of strains. Lower LAB complexity was found on kernels, while a richer biodiversity was observed in semolinas and fermented doughs. For broader microbiota characterisation in doughs before fermentation, the 16S rRNA gene fragment profiling was conducted on the unfermented doughs using MiSeq Illumina. LAB group was represented by Enterococcus, Lactococcus and members of Leuconostocaceae family whose relative abundances differed according to both geographical area and variety of wheat. The culture-independent approach confirmed that pediococci and lactobacilli constituted low abundance members of the semolina LAB microbiota and that although some strains may pass from wheat ear to fermented doughs, most are likely to come from other sources. Copyright © 2016 Elsevier Ltd. All rights reserved.

Crouzon’s Syndrome with Life-Threatening Ear Bleed: Ruptured Jugular Vein Diverticulum Treated by Endovascular Embolization

DOE Office of Scientific and Technical Information (OSTI.GOV)

Mondel, Prabath Kumar, E-mail: prabathmondel@gmail.com; Anand, Sunanda, E-mail: sunandaanand@gmail.com; Limaye, Uday S., E-mail: uslkem@gmail.com

Crouzon’s syndrome is the commonest variety of syndromic craniosynostosis. Life-threatening ear bleed due to ruptured jugular venous diverticulum in Crouzon’s syndrome has not been described previously. In patients with syndromic craniosynostosis, definitive repair of jugular diverticulum by open surgery is fraught with high risk of bleeding, poor functional outcomes, and even death. A 24-year-old woman with Crouzon’s syndrome presented with conductive hearing loss and recurrent episodes of torrential bleeding from her left ear. On computed tomography, a defect in the roof of jugular fossa containing jugular venous diverticulum immediately inferior to the bony external auditory canal was seen. The clinicalmore » presentation, imaging features, and endovascular management of Crouzon’s syndrome due to a ruptured jugular venous diverticulum is described.« less

Anatomical influences on internally coupled ears in reptiles.

PubMed

Young, Bruce A

2016-10-01

Many reptiles, and other vertebrates, have internally coupled ears in which a patent anatomical connection allows pressure waves generated by the displacement of one tympanic membrane to propagate (internally) through the head and, ultimately, influence the displacement of the contralateral tympanic membrane. The pattern of tympanic displacement caused by this internal coupling can give rise to novel sensory cues. The auditory mechanics of reptiles exhibit more anatomical variation than in any other vertebrate group. This variation includes structural features such as diverticula and septa, as well as coverings of the tympanic membrane. Many of these anatomical features would likely influence the functional significance of the internal coupling between the tympanic membranes. Several of the anatomical components of the reptilian internally coupled ear are under active motor control, suggesting that in some reptiles the auditory system may be more dynamic than previously recognized.

Ectodysplasin signalling deficiency in mouse models of hypohidrotic ectodermal dysplasia leads to middle ear and nasal pathology

PubMed Central

Azar, Ali; Piccinelli, Chiara; Brown, Helen; Headon, Denis; Cheeseman, Michael

2016-01-01

Hypohidrotic ectodermal dysplasia (HED) results from mutation of the EDA, EDAR or EDARADD genes and is characterized by reduced or absent eccrine sweat glands, hair follicles and teeth, and defective formation of salivary, mammary and craniofacial glands. Mouse models with HED also carry Eda, Edar or Edaradd mutations and have defects that map to the same structures. Patients with HED have ear, nose and throat disease, but this has not been investigated in mice bearing comparable genetic mutations. We report that otitis media, rhinitis and nasopharyngitis occur at high frequency in Eda and Edar mutant mice and explore the pathogenic mechanisms related to glandular function, microbial and immune parameters in these lines. Nasopharynx auditory tube glands fail to develop in HED mutant mice and the functional implications include loss of lysozyme secretion, reduced mucociliary clearance and overgrowth of nasal commensal bacteria accompanied by neutrophil exudation. Heavy nasopharynx foreign body load and loss of gland protection alters the auditory tube gating function and the auditory tubes can become pathologically dilated. Accumulation of large foreign body particles in the bulla stimulates granuloma formation. Analysis of immune cell populations and myeloid cell function shows no evidence of overt immune deficiency in HED mutant mice. Our findings using HED mutant mice as a model for the human condition support the idea that ear and nose pathology in HED patients arises as a result of nasal and nasopharyngeal gland deficits, reduced mucociliary clearance and impaired auditory tube gating function underlies the pathological sequelae in the bulla. PMID:27378689

Morphology and function of Neandertal and modern human ear ossicles

PubMed Central

David, Romain; Gunz, Philipp; Schmidt, Tobias; Spoor, Fred; Hublin, Jean-Jacques

2016-01-01

The diminutive middle ear ossicles (malleus, incus, stapes) housed in the tympanic cavity of the temporal bone play an important role in audition. The few known ossicles of Neandertals are distinctly different from those of anatomically modern humans (AMHs), despite the close relationship between both human species. Although not mutually exclusive, these differences may affect hearing capacity or could reflect covariation with the surrounding temporal bone. Until now, detailed comparisons were hampered by the small sample of Neandertal ossicles and the unavailability of methods combining analyses of ossicles with surrounding structures. Here, we present an analysis of the largest sample of Neandertal ossicles to date, including many previously unknown specimens, covering a wide geographic and temporal range. Microcomputed tomography scans and 3D geometric morphometrics were used to quantify shape and functional properties of the ossicles and the tympanic cavity and make comparisons with recent and extinct AMHs as well as African apes. We find striking morphological differences between ossicles of AMHs and Neandertals. Ossicles of both Neandertals and AMHs appear derived compared with the inferred ancestral morphology, albeit in different ways. Brain size increase evolved separately in AMHs and Neandertals, leading to differences in the tympanic cavity and, consequently, the shape and spatial configuration of the ossicles. Despite these different evolutionary trajectories, functional properties of the middle ear of AMHs and Neandertals are largely similar. The relevance of these functionally equivalent solutions is likely to conserve a similar auditory sensitivity level inherited from their last common ancestor. PMID:27671643

Ankrd6 is a mammalian functional homolog of Drosophila planar cell polarity gene diego and regulates coordinated cellular orientation in the mouse inner ear.

PubMed

Jones, Chonnettia; Qian, Dong; Kim, Sun Myoung; Li, Shuangding; Ren, Dongdong; Knapp, Lindsey; Sprinzak, David; Avraham, Karen B; Matsuzaki, Fumio; Chi, Fanglu; Chen, Ping

2014-11-01

The coordinated polarization of neighboring cells within the plane of the tissue, known as planar cell polarity (PCP), is a recurring theme in biology. It is required for numerous developmental processes for the form and function of many tissues and organs across species. The genetic pathway regulating PCP was first discovered in Drosophila, and an analogous but distinct pathway is emerging in vertebrates. It consists of membrane protein complexes known as core PCP proteins that are conserved across species. Here we report that the over-expression of the murine Ankrd6 (mAnkrd6) gene that shares homology with Drosophila core PCP gene diego causes a typical PCP phenotype in Drosophila, and mAnkrd6 can rescue the loss of function of diego in Drosophila. In mice, mAnkrd6 protein is asymmetrically localized in cells of the inner ear sensory organs, characteristic of components of conserved core PCP complexes. The loss of mAnkrd6 causes PCP defects in the inner ear sensory organs. Moreover, canonical Wnt signaling is significantly increased in mouse embryonic fibroblasts from mAnkrd6 knockout mice in comparison to wild type controls. Together, these results indicated that mAnkrd6 is a functional homolog of the Drosophila diego gene for mammalian PCP regulation and act to suppress canonical Wnt signaling. Copyright © 2014 Elsevier Inc. All rights reserved.

Auditory interhemispheric transfer in relation to patterns of partial agenesis and hypoplasia of the corpus callosum in spina bifida meningomyelocele

PubMed Central

Hannay, H. Julia; Walker, Amy; Dennis, Maureen; Kramer, Larry; Blaser, Susan; Fletcher, Jack M.

2009-01-01

Spina bifida meningomyelocele with hydrocephalus (SBM) is commonly associated with anomalies of the corpus callosum (CC). We describe MRI patterns of regional CC agenesis and relate CC anomalies to functional laterality based on a dichotic listening test in 90 children with SBM and 27 typically developing controls. Many children with SBM (n = 40) showed regional CC anomalies in the form of agenesis of the rostrum and0or splenium, and a smaller number (n = 20) showed hypoplasia (thinning) of all CC regions (rostrum, genu, body, and splenium). The expected right ear advantage (REA) was exhibited by normal controls and children with SBM having a normal or hypoplastic splenium. It was not shown by children with SBM who were left handed, missing a splenium, or had a higher level spinal cord lesion. Perhaps the right hemisphere of these children is more involved in processing some aspects of linguistic stimuli. PMID:18764972

Classification of Newborn Ear Malformations and their Treatment with the EarWell Infant Ear Correction System.

PubMed

Daniali, Lily N; Rezzadeh, Kameron; Shell, Cheryl; Trovato, Matthew; Ha, Richard; Byrd, H Steve

2017-03-01

A single practice's treatment protocol and outcomes following molding therapy on newborn ear deformations and malformations with the EarWell Infant Ear Correction System were reviewed. A classification system for grading the severity of constricted ear malformations was created on the basis of anatomical findings. A retrospective chart/photograph review of a consecutive series of infants treated with the EarWell System from 2011 to 2014 was undertaken. The infants were placed in either deformation or malformation groups. Three classes of malformation were identified. Data regarding treatment induction, duration of treatment, and quality of outcome were collected for all study patients. One hundred seventy-five infant ear malformations and 303 infant ear deformities were treated with the EarWell System. The average age at initiation of treatment was 12 days; the mean duration of treatment was 37 days. An average of six office visits was required. Treated malformations included constricted ears [172 ears (98 percent)] and cryptotia [three ears (2 percent)]. Cup ear (34 ears) was considered a constricted malformation, in contrast to the prominent ear deformity. Constricted ears were assigned to one of three classes, with each subsequent class indicating increasing severity: class I, 77 ears (45 percent); class II, 81 ears (47 percent); and class III, 14 ears (8 percent). Molding therapy with the EarWell System reduced the severity by an average of 1.2 points (p < 0.01). Complications included minor superficial excoriations and abrasions. The EarWell System was shown to be effective in eliminating or reducing the need for surgery in all but the most severe malformations. Therapeutic, IV.

Developmental Continuity in Teleo-Functional Explanation: Reasoning about Nature among Romanian Romani Adults

ERIC Educational Resources Information Center

Casler, Krista; Kelemen, Deborah

2008-01-01

Teleo-functional explanations account for objects in terms of purpose, helping us understand objects such as pencils (for writing) and body parts such as ears (for hearing). Western-educated adults restrict teleo-functional attributions to artifact, biological, and behavioral phenomena, considering such explanations less appropriate for nonliving…

Assessment of the influence of whole body vibration on Cochlear function

PubMed Central

2012-01-01

Background Whole body vibration (WBV) is a potentially harmful consequence resulting from the dissipation of energy by industrial machineries. The result of WBV exposure on the auditory system remains unknown. The objective of the present research was to evaluate the influence of WBV on cochlear function, in particular outer hair cell function. It is hypothesized that WBV impairs cochlear function resulting in decreased Distortion Product Otoacoustic Emission (DPOAE) levels (Ldp) in rabbits subjected to WBV. Methods Twelve rabbits were equally divided into vibration and control groups. Animals in vibration group were exposed to 1.0 ms-2 r.m.s vertical WBV at 4–8 Hz for 8 h/day during 5 consecutive days. Outer hair cell function was assessed by comparing repeated-measurements of DPOAE levels (Ldp) across a range of f2 frequencies in rabbits both exposed and unexposed to WBV. DPOAE level shifts (LSdp) were compared across ears, frequencies, groups, and times. Results No differences were seen over time in DPOAE levels in the non-exposed rabbits (p = 0.082). Post-exposure Ldp in rabbits exposed to WBV were significantly increased at all test frequencies in both ears compared to baseline measures (p = 0.021). The greatest increase in Ldp following exposure was seen at 5888.5 Hz (mean shift = 13.25 dB). Post-exposure Ldp in rabbits exposed to WBV were not significantly different between the right and left ears (p = 0.083). Conclusion WBV impairs cochlear function resulting in increased DPOAE responses in rabbits exposed to WBV. DPOAE level shifts occurred over a wide range of frequencies following prolonged WBV in rabbits. PMID:22720724

Anatomical variants of tympanic compartments and their aeration pathways involved in the pathogenesis of middle ear inflammatory disease

PubMed Central

MANIU, ALMA; CATANA, IULIU V.; HARABAGIU, OANA; PETRI, MARIA; COSGAREA, MARCEL

2013-01-01

Aim The aim of this article is to review the anatomy of middle ear compartments and folds and to demonstrate through anatomical evidence their presence at birth. Additionally, their role in the obstructions of middle ear ventilatory pathway is highlighted. Methods Ninety-eight adult temporal bones, with no history of auricular disease and fifteen newborn temporal bones were studied by micro dissection. Documentation was done by color photography using the operation microscope Results Our micro-dissections have showed that mucosal folds from the middle ear are steadily present since birth, given that they were found in all newborn temporal bones. The mucosal folds in our normal adult material, showed some variations including membrane defects but they were constantly present. Our micro dissections showed that the epitympanic diaphragm consisted, in addition to malleal ligamental folds and ossicles, of only two constantly present folds: the tensor tympani fold and the incudomalleal fold. When the tensor fold is complete the only ventilation pathway to the anterior epitympanic space is through the isthmus, whereas its absence creates an efficient additional aeration route from the Eustachian tube to the epitympanum. Conclusions The goal of surgery in the chronic pathology of the middle ear should be restoration of normal ventilation of the attical-mastoid area. This is possible by removing the tensor fold and restoring the functionality of the isthmus tympani. PMID:26527977

Roles of an anti-tuberculosis medication and surgery in patients with tuberculous otitis media.

PubMed

Kwon, Minsu; Choi, Seung Hyo; Chung, Jong Woo

2010-06-01

The standard treatment for tuberculous otitis media (TOM) without complications consists of anti-tuberculosis (anti-TB) medication, with which we experienced good treatment outcomes. However, surgery is required for recovery of anatomy and hearing function. To determine the clinical characteristics of TOM that might optimize diagnosis and to evaluate the differences in clinical courses between patients treated with and without surgery. We analyzed 14 patients (16 ears) who had been diagnosed and treated for TOM. Radiologic findings, laboratory data, and audiometry results were also evaluated. Patients were divided into a chemotherapy group and a surgery group according to treatment modality. Temporal bone CT (TBCT) showed total occupation of the tympanic cavity by soft tissue and little evidence of ossicular erosion. In the chemotherapy group, dry ears were obtained in all but one patient (14 ears) after treatment. Normalized tympanic membrane (TM) was found in 50% in the chemotherapy group and in 75% in the surgery group. The air-bone gap (ABG) changed from 40.3 +/- 2.5 dB to 47.0 +/- 19.2 dB in the chemotherapy group and from 35.2 +/- 7.6 dB to 30.2 +/- 11.4 dB in the surgery group. After treatment, ABG improved by > 10 dB in one ear in the chemotherapy group and in four ears in the surgery group.

Anatomy of the lamprey ear: morphological evidence for occurrence of horizontal semicircular ducts in the labyrinth of Petromyzon marinus

USGS Publications Warehouse

Maklad, Adel; Reed, Caitlyn; Johnson, Nicholas S.; Fritzsch, Bernd

2014-01-01

In jawed (gnathostome) vertebrates, the inner ears have three semicircular canals arranged orthogonally in the three Cartesian planes: one horizontal (lateral) and two vertical canals. They function as detectors for angular acceleration in their respective planes. Living jawless craniates, cyclostomes (hagfish and lamprey) and their fossil records seemingly lack a lateral horizontal canal. The jawless vertebrate hagfish inner ear is described as a torus or doughnut, having one vertical canal, and the jawless vertebrate lamprey having two. These observations on the anatomy of the cyclostome (jawless vertebrate) inner ear have been unchallenged for over a century, and the question of how these jawless vertebrates perceive angular acceleration in the yaw (horizontal) planes has remained open. To provide an answer to this open question we reevaluated the anatomy of the inner ear in the lamprey, using stereoscopic dissection and scanning electron microscopy. The present study reveals a novel observation: the lamprey has two horizontal semicircular ducts in each labyrinth. Furthermore, the horizontal ducts in the lamprey, in contrast to those of jawed vertebrates, are located on the medial surface in the labyrinth rather than on the lateral surface. Our data on the lamprey horizontal duct suggest that the appearance of the horizontal canal characteristic of gnathostomes (lateral) and lampreys (medial) are mutually exclusive and indicate a parallel evolution of both systems, one in cyclostomes and one in gnathostome ancestors.

Acoustic Immittance, Absorbance, and Reflectance in the Human Ear Canal

PubMed Central

Rosowski, John J.; Wilber, Laura Ann

2015-01-01

Ear canal measurements of acoustic immittance (a term that groups impedance and its inverse, admittance) and the related quantities of acoustic reflectance and power absorbance have been used to assess auditory function and aid in the differential diagnosis of conductive hearing loss for over 50 years. The change in such quantities after stimulation of the acoustic reflex also has been used in diagnosis. In this article, we define these quantities, describe how they are commonly measured, and discuss appropriate calibration procedures and standards necessary for accurate immittance/reflectance measurements. PMID:27516708

Changes in the Adult Vertebrate Auditory Sensory Epithelium After Trauma

PubMed Central

Oesterle, Elizabeth C.

2012-01-01

Auditory hair cells transduce sound vibrations into membrane potential changes, ultimately leading to changes in neuronal firing and sound perception. This review provides an overview of the characteristics and repair capabilities of traumatized auditory sensory epithelium in the adult vertebrate ear. Injured mammalian auditory epithelium repairs itself by forming permanent scars but is unable to regenerate replacement hair cells. In contrast, injured non-mammalian vertebrate ear generates replacement hair cells to restore hearing functions. Non-sensory support cells within the auditory epithelium play key roles in the repair processes. PMID:23178236

Separating the contributions of olivocochlear and middle ear muscle reflexes in modulation of distortion product otoacoustic emission levels.

PubMed

Wolter, Nikolaus E; Harrison, Robert V; James, Adrian L

2014-01-01

Mediated by the medial olivocochlear system (MOCS), distortion product otoacoustic emission (DPOAE) levels are reduced by presentation of contralateral acoustic stimuli. Such acoustic signals can also evoke a middle ear muscle reflex (MEMR) that also attenuates recorded DPOAE levels. Our aim is to clearly differentiate these two inhibitory mechanisms and to analyze each separately, perhaps allowing the development of novel tests of hearing function. DPOAE were recorded in real time from chinchillas with normal auditory brainstem response thresholds and middle ear function. Amplitude reduction and its onset latency caused by contralateral presentation of intermittent narrow-band noise (NBN) were measured. Stapedius and tensor tympani muscle tendons were divided without disturbing the ossicular chain, and DPOAE testing was repeated. Peak reduction of (2f1 - f2) DPOAE levels occurred when the center frequency of contralateral NBN approximated the primary tone f2, indicating an f2-frequency-specific response. For a 4.5-kHz centered NBN, DPOAE (f2 = 4.4 kHz) inhibition was 0.1 dB (p < 0.001). This response remained present after tendon division, consistent with an MOCS origin. Low-frequency NBN (center frequency: 0.5 kHz) reduced otoacoustic emission levels (0.1 dB, p < 0.001) across a wide range of DPOAE frequencies. This low-frequency response was abolished by division of the middle ear muscle tendons, clearly indicating MEMR involvement. Following middle ear muscle tendon division, DPOAE inhibition by contralateral stimuli approximating the primary tone f2 persists, whereas responses evoked by lower contralateral frequencies are abolished. This distinguishes the different roles of the MOCS (f2 frequency specific) and MEMR (low frequency only) in contralateral modulation of DPOAE. This analysis helps clarify the pathways involved in an objective test that might have clinical benefit in the testing of neonates.

In vivo imaging of mammalian cochlear blood flow using fluorescence microendoscopy.

PubMed

Monfared, Ashkan; Blevins, Nikolas H; Cheung, Eunice L M; Jung, Juergen C; Popelka, Gerald; Schnitzer, Mark J

2006-02-01

We sought to develop techniques for visualizing cochlear blood flow in live mammalian subjects using fluorescence microendoscopy. Inner ear microcirculation appears to be intimately involved in cochlear function. Blood velocity measurements suggest that intense sounds can alter cochlear blood flow. Disruption of cochlear blood flow may be a significant cause of hearing impairment, including sudden sensorineural hearing loss. However, inability to image cochlear blood flow in a nondestructive manner has limited investigation of the role of inner ear microcirculation in hearing function. Present techniques for imaging cochlear microcirculation using intravital light microscopy involve extensive perturbations to cochlear structure, precluding application in human patients. The few previous endoscopy studies of the cochlea have suffered from optical resolution insufficient for visualizing cochlear microvasculature. Fluorescence microendoscopy is an emerging minimally invasive imaging modality that provides micron-scale resolution in tissues inaccessible to light microscopy. In this article, we describe the use of fluorescence microendoscopy in live guinea pigs to image capillary blood flow and movements of individual red blood cells within the basal turn of the cochlea. We anesthetized eight adult guinea pigs and accessed the inner ear through the mastoid bulla. After intravenous injection of fluorescein dye, we made a limited cochleostomy and introduced a compound doublet gradient refractive index endoscope probe 1 mm in diameter into the inner ear. We then imaged cochlear blood flow within individual vessels in an epifluorescence configuration using one-photon fluorescence microendoscopy. We observed single red blood cells passing through individual capillaries in several cochlear structures, including the round window membrane, spiral ligament, osseous spiral lamina, and basilar membrane. Blood flow velocities within inner ear capillaries varied widely, with observed speeds reaching up to approximately 500 microm/s. Fluorescence microendoscopy permits visualization of cochlear microcirculation with micron-scale optical resolution and determination of blood flow velocities through analysis of video sequences.

Artificial Induction of Sox21 Regulates Sensory Cell Formation in the Embryonic Chicken Inner Ear

PubMed Central

Freeman, Stephen D.; Daudet, Nicolas

2012-01-01

During embryonic development, hair cells and support cells in the sensory epithelia of the inner ear derive from progenitors that express Sox2, a member of the SoxB1 family of transcription factors. Sox2 is essential for sensory specification, but high levels of Sox2 expression appear to inhibit hair cell differentiation, suggesting that factors regulating Sox2 activity could be critical for both processes. Antagonistic interactions between SoxB1 and SoxB2 factors are known to regulate cell differentiation in neural tissue, which led us to investigate the potential roles of the SoxB2 member Sox21 during chicken inner ear development. Sox21 is normally expressed by sensory progenitors within vestibular and auditory regions of the early embryonic chicken inner ear. At later stages, Sox21 is differentially expressed in the vestibular and auditory organs. Sox21 is restricted to the support cell layer of the auditory epithelium, while it is enriched in the hair cell layer of the vestibular organs. To test Sox21 function, we used two temporally distinct gain-of-function approaches. Sustained over-expression of Sox21 from early developmental stages prevented prosensory specification, and abolished the formation of both hair cells and support cells. However, later induction of Sox21 expression at the time of hair cell formation in organotypic cultures of vestibular epithelia inhibited endogenous Sox2 expression and Notch activity, and biased progenitor cells towards a hair cell fate. Interestingly, Sox21 did not promote hair cell differentiation in the immature auditory epithelium, which fits with the expression of endogenous Sox21 within mature support cells in this tissue. These results suggest that interactions among endogenous SoxB family transcription factors may regulate sensory cell formation in the inner ear, but in a context-dependent manner. PMID:23071561

Growth hormone treatment does not affect incidences of middle ear disease or hearing loss in infants and toddlers with Turner syndrome.

PubMed

Davenport, Marsha L; Roush, Jackson; Liu, Chunhua; Zagar, Anthony J; Eugster, Erica; Travers, Sharon; Fechner, Patricia Y; Quigley, Charmian A

2010-01-01

No randomized, controlled, prospective study has evaluated the effect of growth hormone (GH) on the rates of middle ear (ME) disease and hearing loss in girls with Turner syndrome (TS). A 2-year, prospective, randomized, controlled, open-label, multicenter, clinical trial ('Toddler Turner Study'; August 1999 to August 2003) was carried out. The study was conducted at 11 US pediatric endocrine centers. Eighty-eight girls with TS, aged 9 months to 4 years, were enrolled. The interventions comprised recombinant GH (50 microg/kg/day, n = 45) or no treatment (n = 43) for 2 years. The outcome measures included occurrence rates of ear-related problems, otitis media (OM) and associated antibiotic treatments, tympanometric assessment of ME function and hearing assessment by audiology. At baseline, 57% of the girls (mean age = 1.98 +/- 1.00 years) had a history of recurrent OM, 33% had undergone tympanostomy tube (t-tube) insertion and 27% had abnormal hearing. There was no significant difference between the treatment groups for annual incidence of OM episodes (untreated control: 1.9 +/- 1.4; GH-treated: 1.5 +/- 1.6, p = 0.17). A quarter of the subjects underwent ear surgeries (mainly t-tube insertions) during the study. Recurrent or persistent abnormality of ME function on tympanometry was present in 28-45% of the girls without t-tubes at the 6 postbaseline visits. Hearing deficits were found in 19-32% of the girls at the annual postbaseline visits. Most of these were conductive deficits, however, 2 girls had findings consistent with sensorineural hearing loss, which was evident before 3 years of age. Ear and hearing problems are common in infants and toddlers with TS and are not significantly influenced by GH treatment. Girls with TS need early, regular and thorough ME monitoring by their primary care provider and/or otolaryngologist, and at least annual hearing evaluations by a pediatric audiologist. Copyright 2010 S. Karger AG, Basel.

Hearing Loss in HIV-Infected Children in Lilongwe, Malawi

PubMed Central

Hrapcak, Susan; Kuper, Hannah; Bartlett, Peter; Devendra, Akash; Makawa, Atupele; Kim, Maria; Kazembe, Peter; Ahmed, Saeed

2016-01-01

Introduction With improved access to antiretroviral therapy (ART), HIV infection is becoming a chronic illness. Preliminary data suggest that HIV-infected children have a higher risk of disabilities, including hearing impairment, although data are sparse. This study aimed to estimate the prevalence and types of hearing loss in HIV-infected children in Lilongwe, Malawi. Methods This was a cross-sectional survey of 380 HIV-infected children aged 4–14 years attending ART clinic in Lilongwe between December 2013-March 2014. Data was collected through pediatric quality of life and sociodemographic questionnaires, electronic medical record review, and detailed audiologic testing. Hearing loss was defined as >20 decibels hearing level (dBHL) in either ear. Predictors of hearing loss were explored by regression analysis generating age- and sex-adjusted odds ratios. Children with significant hearing loss were fitted with hearing aids. Results Of 380 patients, 24% had hearing loss: 82% conductive, 14% sensorineural, and 4% mixed. Twenty-one patients (23% of those with hearing loss) were referred for hearing aid fitting. There was a higher prevalence of hearing loss in children with history of frequent ear infections (OR 7.4, 4.2–13.0) and ear drainage (OR 6.4, 3.6–11.6). Hearing loss was linked to history of WHO Stage 3 (OR 2.4, 1.2–4.5) or Stage 4 (OR 6.4, 2.7–15.2) and history of malnutrition (OR 2.1, 1.3–3.5), but not to duration of ART or CD4. Only 40% of caregivers accurately perceived their child’s hearing loss. Children with hearing impairment were less likely to attend school and had poorer emotional (p = 0.02) and school functioning (p = 0.04). Conclusions There is an urgent need for improved screening tools, identification and treatment of hearing problems in HIV-infected children, as hearing loss was common in this group and affected school functioning and quality of life. Clear strategies were identified for prevention and treatment, since most hearing loss was conductive in nature, likely due to frequent ear infections, and many children with hearing loss qualified for hearing aids. Screening strategies need to be developed and tested since caregivers were not reliable at identifying hearing loss, and often mis-identified children with normal hearing as having hearing loss. Children with frequent ear infections, ear drainage, TB, severe HIV disease, or low BMI should receive more frequent ear assessments and hearing evaluations. PMID:27551970

Responses of the ear to low frequency sounds, infrasound and wind turbines.

PubMed

Salt, Alec N; Hullar, Timothy E

2010-09-01

Infrasonic sounds are generated internally in the body (by respiration, heartbeat, coughing, etc) and by external sources, such as air conditioning systems, inside vehicles, some industrial processes and, now becoming increasingly prevalent, wind turbines. It is widely assumed that infrasound presented at an amplitude below what is audible has no influence on the ear. In this review, we consider possible ways that low frequency sounds, at levels that may or may not be heard, could influence the function of the ear. The inner ear has elaborate mechanisms to attenuate low frequency sound components before they are transmitted to the brain. The auditory portion of the ear, the cochlea, has two types of sensory cells, inner hair cells (IHC) and outer hair cells (OHC), of which the IHC are coupled to the afferent fibers that transmit "hearing" to the brain. The sensory stereocilia ("hairs") on the IHC are "fluid coupled" to mechanical stimuli, so their responses depend on stimulus velocity and their sensitivity decreases as sound frequency is lowered. In contrast, the OHC are directly coupled to mechanical stimuli, so their input remains greater than for IHC at low frequencies. At very low frequencies the OHC are stimulated by sounds at levels below those that are heard. Although the hair cells in other sensory structures such as the saccule may be tuned to infrasonic frequencies, auditory stimulus coupling to these structures is inefficient so that they are unlikely to be influenced by airborne infrasound. Structures that are involved in endolymph volume regulation are also known to be influenced by infrasound, but their sensitivity is also thought to be low. There are, however, abnormal states in which the ear becomes hypersensitive to infrasound. In most cases, the inner ear's responses to infrasound can be considered normal, but they could be associated with unfamiliar sensations or subtle changes in physiology. This raises the possibility that exposure to the infrasound component of wind turbine noise could influence the physiology of the ear. Copyright (c) 2010 Elsevier B.V. All rights reserved.

A comparison of tympanometry with 226 Hz and 1000 Hz probe tones in children with Down syndrome.

PubMed

Lewis, Meagan P; Bradford Bell, Elizabeth; Evans, Adele K

2011-12-01

For children with Down syndrome, the incidence of hearing loss may be as high as 78% [1], therefore the American Academy of Pediatrics recommends regular screening for the presence of hearing abnormalities. Tympanometry is used as an indication of middle ear pathology. In our experience, Down's patients' tympanograms do not always correlate with otoscopic findings. Down's patients have joint laxity, small ear canals, anterior tympanic membrane orientation and softer tissue composition, all factors thought to affect tympanogram results in infants. Because the use of the 1000 Hz tympanometry is widely recognized as standard procedure in the evaluation of infants aged 0-6 months, we propose it may have greater reliability in testing patients with Down syndrome. Compare the results of visual inspection of the tympanic membrane by a Pediatric Otolaryngologist to the results of tympanometry at traditional probe tone (226 Hz) and at the infant probe tone (1000 Hz). Institutional Review Board - approved prospective study of 26 subject-ears in patients with Down syndrome aged 6 months-18 years but recent stable middle ear/Eustachian tube function using physical examination and tympanometric probe tones at 226 Hz and 1000 Hz. Subject-ears were examined with record of "clear of effusion," showed the presence of "fluid," or were to be "excluded." Blinded to ear exam results, tympanometry was then completed with record of which Jerger classification tympanogram was found at each frequency. Although the sensitivity of each test was 1, the specificity of the 1000 Hz tympanometry (100%) in this study was markedly improved compared to the specificity of the 226 Hz tympanometry (71%) (p=0.016). This pilot study demonstrated evidence that tympanometry in children with Down syndrome may be more reliable at 1000 Hz than at 226 Hz in detecting the presence of middle ear effusion beyond infancy. Use of the 1000 Hz probe tone yielded fewer false positives for disease (type B tympanograms in the setting of absent middle ear disease). Further studies of a larger patient population are needed to corroborate these results. Copyright © 2011 Elsevier Ireland Ltd. All rights reserved.

Impact of xylomethazoline on eustachian tube function in healthy participants.

PubMed

Meyer, Moritz F; Mikolajczak, Stefanie; Korthäuer, Christine; Jumah, Masen D; Hahn, Moritz; Grosheva, Maria; Lüers, Jan-Christoffer; Hüttenbrink, Karl-Bernd; Beutner, Dirk

2015-06-01

The use of decongestants is common in otitis media eustachian tube (ET) dysfunction. However, the underlying mechanism and the type of action on the complex middle ear pressure equalization system are poorly understood. Here, by use of the pressure chamber, we investigated the impact of intranasal decongestive therapy (xylomethazoline) on ET function. Thirty healthy participants (60 ears) were exposed to a predetermined profile of phases of compression and decompression in a hypobaric and hyperbaric pressure chamber. ET opening pressure, ET opening duration, ET opening frequency, and ET closing pressure were determined before and after intranasal application of xylomethazoline. A significantly higher number of ET openings (ET opening frequency) in passive equalization condition could be measured after application of decongestants than before. No significant difference could be found in the values of ET opening pressure, ET opening duration, and ET closing pressure parameters before in comparison with the values after application of xylomethazoline. We conclude that xylomethazoline might only have a minor effect during active and passive middle ear pressure equalization. Larger cohorts and targeted application of decongestants should be tested to confirm these preliminary data and to find new evidence on the effects of decongestants.

GATA3 controls the specification of prosensory domain and neuronal survival in the mouse cochlea

PubMed Central

Luo, Xiong-jian; Deng, Min; Xie, Xiaoling; Huang, Liang; Wang, Hui; Jiang, Lichun; Liang, Guoqing; Hu, Fang; Tieu, Roger; Chen, Rui; Gan, Lin

2013-01-01

HDR syndrome (also known as Barakat syndrome) is a developmental disorder characterized by hypoparathyroidism, sensorineural deafness and renal disease. Although genetic mapping and subsequent functional studies indicate that GATA3 haplo-insufficiency causes human HDR syndrome, the role of Gata3 in sensorineural deafness and auditory system development is largely unknown. In this study, we show that Gata3 is continuously expressed in the developing mouse inner ear. Conditional knockout of Gata3 in the developing inner ear disrupts the morphogenesis of mouse inner ear, resulting in a disorganized and shortened cochlear duct with significant fewer hair cells and supporting cells. Loss of Gata3 function leads to the failure in the specification of prosensory domain and subsequently, to increased cell death in the cochlear duct. Moreover, though the initial generation of cochleovestibular ganglion (CVG) cells is not affected in Gata3-null mice, spiral ganglion neurons (SGNs) are nearly depleted due to apoptosis. Our results demonstrate the essential role of Gata3 in specifying the prosensory domain in the cochlea and in regulating the survival of SGNs, thus identifying a molecular mechanism underlying human HDR syndrome. PMID:23666531

Historical Aspects of Inner Ear Anatomy and Biology that Underlie the Design of Hearing and Balance Prosthetic Devices.

PubMed

Van De Water, Thomas R

2012-11-01

This review presents some of the major historical events that advanced the body of knowledge of the anatomy of the inner ear and its sensory receptors as well as the biology of these receptors that underlies the sensory functions of hearing and balance. This knowledge base of the inner ear's structure/function has been an essential factor for the design and construction of prosthetic devices to aid patients with deficits in their senses of hearing and balance. Prosthetic devices are now available for severely hearing impaired and deaf patients to restore hearing and are known as cochlear implants and auditory brain stem implants. A prosthetic device for patients with balance disorders is being perfected and is in an animal model testing phase with another prosthetic device for controlling intractable dizziness in Meniere's patients currently being evaluated in clinical testing. None of this would have been possible without the pioneering studies and discoveries of the investigators mentioned in this review and with the work of many other talented investigators to numerous to be covered in this review. Copyright © 2012 Wiley Periodicals, Inc.

Age and Gender Effects on Wideband Absorbance in Adults With Normal Outer and Middle Ear Function.

PubMed

Mazlan, Rafidah; Kei, Joseph; Ya, Cheng Li; Yusof, Wan Nur Hanim Mohd; Saim, Lokman; Zhao, Fei

2015-08-01

This study examined the effects of age and gender on wideband energy absorbance in adults with normal middle ear function. Forty young adults (14 men, 26 women, aged 20-38 years), 31 middle-aged adults (16 men, 15 women, aged 42-64 years), and 30 older adults (20 men, 10 women, aged 65-82 years) were assessed. Energy absorbance (EA) data were collected at 30 frequencies using a prototype commercial instrument developed by Interacoustics. Results showed that the young adult group had significantly lower EA (between 400 and 560 Hz) than the middle-aged group. However, the middle-aged group showed significantly lower EA (between 2240 and 5040 Hz) than the young adult group. In addition, the older adult group had significantly lower EA than the young adult group (between 2520 and 5040 Hz). No significant difference in EA was found at any frequency between middle-aged and older adults. Across age groups, gender differences were found with men having significantly higher EA values than women at lower frequencies, whereas women had significantly higher EA at higher frequencies. This study provides evidence of the influence of gender and age on EA in adults with normal outer and middle ear function. These findings support the importance of establishing age- and gender-specific EA norms for the adult population.

Phylogenetic and functional implications of the ear region anatomy of Glossotherium robustum (Xenarthra, Mylodontidae) from the Late Pleistocene of Argentina

NASA Astrophysics Data System (ADS)

Boscaini, Alberto; Iurino, Dawid A.; Billet, Guillaume; Hautier, Lionel; Sardella, Raffaele; Tirao, German; Gaudin, Timothy J.; Pujos, François

2018-04-01

Several detailed studies of the external morphology of the ear region in extinct sloths have been published in the past few decades, and this anatomical region has proved extremely helpful in elucidating the phylogenetic relationships among the members of this mammalian clade. Few studies of the inner ear anatomy in these peculiar animals were conducted historically, but these are increasing in number in recent years, in both the extinct and extant representatives, due to wider access to CT-scanning facilities, which allow non-destructive access to internal morphologies. In the present study, we analyze the extinct ground sloth Glossotherium robustum and provide a description of the external features of the ear region and the endocranial side of the petrosal bone, coupled with the first data on the anatomy of the bony labyrinth. Some features observable in the ear region of G. robustum (e.g., the shape and size of the entotympanic bone and the morphology of the posteromedial surface of the petrosal) are highly variable, both intraspecifically and intraindividually. The form of the bony labyrinth of G. robustum is also described, providing the first data from this anatomical region for the family Mylodontidae. The anatomy of the bony labyrinth of the genus Glossotherium is here compared at the level of the superorder Xenarthra, including all available extant and extinct representatives, using geometric morphometric methods. In light of the new data, we discuss the evolution of inner ear anatomy in the xenarthran clade, and most particularly in sloths, considering the influence of phylogeny, allometry, and physiology on the shape of this highly informative region of the skull. These analyses show that the inner ear of Glossotherium more closely resembles that of the extant anteaters, and to a lesser extent those of the giant ground sloth Megatherium and euphractine armadillos, than those of the extant sloths Bradypus and Choloepus, further demonstrating the striking morphological convergence between the two extant sloth genera.

Phylogenetic and functional implications of the ear region anatomy of Glossotherium robustum (Xenarthra, Mylodontidae) from the Late Pleistocene of Argentina.

PubMed

Boscaini, Alberto; Iurino, Dawid A; Billet, Guillaume; Hautier, Lionel; Sardella, Raffaele; Tirao, German; Gaudin, Timothy J; Pujos, François

2018-03-27

Several detailed studies of the external morphology of the ear region in extinct sloths have been published in the past few decades, and this anatomical region has proved extremely helpful in elucidating the phylogenetic relationships among the members of this mammalian clade. Few studies of the inner ear anatomy in these peculiar animals were conducted historically, but these are increasing in number in recent years, in both the extinct and extant representatives, due to wider access to CT-scanning facilities, which allow non-destructive access to internal morphologies. In the present study, we analyze the extinct ground sloth Glossotherium robustum and provide a description of the external features of the ear region and the endocranial side of the petrosal bone, coupled with the first data on the anatomy of the bony labyrinth. Some features observable in the ear region of G. robustum (e.g., the shape and size of the entotympanic bone and the morphology of the posteromedial surface of the petrosal) are highly variable, both intraspecifically and intraindividually. The form of the bony labyrinth of G. robustum is also described, providing the first data from this anatomical region for the family Mylodontidae. The anatomy of the bony labyrinth of the genus Glossotherium is here compared at the level of the superorder Xenarthra, including all available extant and extinct representatives, using geometric morphometric methods. In light of the new data, we discuss the evolution of inner ear anatomy in the xenarthran clade, and most particularly in sloths, considering the influence of phylogeny, allometry, and physiology on the shape of this highly informative region of the skull. These analyses show that the inner ear of Glossotherium more closely resembles that of the extant anteaters, and to a lesser extent those of the giant ground sloth Megatherium and euphractine armadillos, than those of the extant sloths Bradypus and Choloepus, further demonstrating the striking morphological convergence between the two extant sloth genera.

[Effect size on resonance of the outer ear canal by simulation of middle ear lesions using a temporal bone preparation].

PubMed

Scheinpflug, L; Vorwerk, U; Begall, K

1995-01-01

By means of a model of the external and the middle ear it is possible to simulate various, exactly defined pathological conditions of the middle ear and to describe their influence on ear canal resonance. Starting point of the investigations are fresh postmortem preparations of 8 human temporal bones with an intact ear drum and a retained skin of the ear canal. The compliance of the middle ear does not significantly differ from the clinical data of probands with healthy ears. After antrotomy it is possible to simulate pathological conditions of the middle ear one after the other at the same temporal bone. The influence of the changed middle ear conditions on ear drum compliance, ear canal volume and on the resonance curve of the external ear canal was investigated. For example, the middle ear was filled with water to create approximately the same conditions as in acute serous otitis media. In this middle ear condition a significant increase of the sound pressure amplification was found, on an average by 4 decibels compared to the unchanged temporal bone model. A small increase in resonance frequency was also measured. The advantages of this model are the approximately physiological conditions and the constant dimensions of the external and middle ear.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Poston, Ted M.; Thrall, Karla D.; Penner, Jocelyn D.

I was asked to submit a response to the Protocol Review forum for the journal LabAnimal by Dr. Jerald Silverman. This forum request views and opinions on issues that are faced by research animal welfare committees. The particular issue is: Dr. John Smith, a distinguished investigator at Great Eastern University, had spent his career searching for a treatment for hearing loss. After 20 years of research, he developed a drug that potentially could improve auditory function after damage to the inner ear. The drug was administered by injection into the middle ear with the use of a fine needle insertedmore » through the eardrum. Smith submitted a protocol to the IACUC to conduct a small study on cats, proposing to treat one group of animals with the drug and another with saline, to determine if it prevented the changes in the anatomy of the inner ear that normally occur with aging.« less

Modeling microstructure of incudostapedial joint and the effect on cochlear input

NASA Astrophysics Data System (ADS)

Gan, Rong Z.; Wang, Xuelin

2015-12-01

The incudostapedial joint (ISJ) connects the incus to stapes in human ear and plays an important role for sound transmission from the tympanic membrane (TM) to cochlea. ISJ is a synovial joint composed of articular cartilage on the lenticular process and stapes head with the synovial fluid between them. However, there is no study on how the synovial ISJ affects the middle ear and cochlear functions. Recently, we have developed a 3-dimensinal finite element (FE) model of synovial ISJ and connected the model to our comprehensive FE model of the human ear. The motions of TM, stapes footplate, and basilar membrane and the pressures in scala vestibule and scala tympani were derived over frequencies and compared with experimental measurements. Results show that the synovial ISJ affects sound transmission into cochlea and the frequency-dependent viscoelastic behavior of ISJ provides protection for cochlea from high intensity sound.

Hearing with an atympanic ear: good vibration and poor sound-pressure detection in the royal python, Python regius.

PubMed

Christensen, Christian Bech; Christensen-Dalsgaard, Jakob; Brandt, Christian; Madsen, Peter Teglberg

2012-01-15

Snakes lack both an outer ear and a tympanic middle ear, which in most tetrapods provide impedance matching between the air and inner ear fluids and hence improve pressure hearing in air. Snakes would therefore be expected to have very poor pressure hearing and generally be insensitive to airborne sound, whereas the connection of the middle ear bone to the jaw bones in snakes should confer acute sensitivity to substrate vibrations. Some studies have nevertheless claimed that snakes are quite sensitive to both vibration and sound pressure. Here we test the two hypotheses that: (1) snakes are sensitive to sound pressure and (2) snakes are sensitive to vibrations, but cannot hear the sound pressure per se. Vibration and sound-pressure sensitivities were quantified by measuring brainstem evoked potentials in 11 royal pythons, Python regius. Vibrograms and audiograms showed greatest sensitivity at low frequencies of 80-160 Hz, with sensitivities of -54 dB re. 1 m s(-2) and 78 dB re. 20 μPa, respectively. To investigate whether pythons detect sound pressure or sound-induced head vibrations, we measured the sound-induced head vibrations in three dimensions when snakes were exposed to sound pressure at threshold levels. In general, head vibrations induced by threshold-level sound pressure were equal to or greater than those induced by threshold-level vibrations, and therefore sound-pressure sensitivity can be explained by sound-induced head vibration. From this we conclude that pythons, and possibly all snakes, lost effective pressure hearing with the complete reduction of a functional outer and middle ear, but have an acute vibration sensitivity that may be used for communication and detection of predators and prey.

Neutrophil Extracellular Traps and Fibrin in Otitis Media: Analysis of Human and Chinchilla Temporal Bones.

PubMed

Schachern, Patricia A; Kwon, Geeyoun; Briles, David E; Ferrieri, Patricia; Juhn, Steven; Cureoglu, Sebahattin; Paparella, Michael M; Tsuprun, Vladimir

2017-10-01

Bacterial resistance in acute otitis can result in bacterial persistence and biofilm formation, triggering chronic and recurrent infections. To investigate the middle ear inflammatory response to bacterial infection in human and chinchilla temporal bones. Six chinchillas underwent intrabullar inoculations with 0.5 mL of 106 colony-forming units (CFUs) of Streptococcus pneumoniae, serotype 2. Two days later, we counted bacteria in middle ear effusions postmortem. One ear from each chinchilla was processed in paraffin and sectioned at 5 µm. The opposite ear was embedded in epoxy resin, sectioned at a thickness of 1 µm, and stained with toluidine blue. In addition, we examined human temporal bones from 2 deceased donors with clinical histories of otitis media (1 with acute onset otitis media, 1 with recurrent infection). Temporal bones had been previously removed at autopsy, processed, embedded in celloidin, and cut at a thickness of 20 µm. Sections of temporal bones from both chinchillas and humans were stained with hematoxylin-eosin and immunolabeled with antifibrin and antihistone H4 antibodies. Histopatological and imminohistochemical changes owing to otitis media. Bacterial counts in chinchilla middle ear effusions 2 days after inoculation were approximately 2 logs above initial inoculum counts. Both human and chinchilla middle ear effusions contained bacteria embedded in a fibrous matrix. Some fibers in the matrix showed positive staining with antifibrin antibody, others with antihistone H4 antibody. In acute and recurrent otitis media, fibrin and neutrophil extracellular traps (NETs) are part of the host inflammatory response to bacterial infection. In the early stages of otitis media the host defense system uses fibrin to entrap bacteria, and NETs function to eliminate bacteria. In chronic otitis media, fibrin and NETs appear to persist.

Reasons for low uptake of referrals to ear and hearing services for children in Malawi.

PubMed

Bright, Tess; Mulwafu, Wakisa; Thindwa, Richard; Zuurmond, Maria; Polack, Sarah

2017-01-01

Early detection and appropriate intervention for children with hearing impairment is important for maximizing functioning and quality of life. The lack of ear and hearing services in low income countries is a significant challenge, however, evidence suggests that even where such services are available, and children are referred to them, uptake is low. The aim of this study was to assess uptake of and barriers to referrals to ear and hearing services for children in Thyolo District, Malawi. This was a mixed methods study. A survey was conducted with 170 caregivers of children who were referred for ear and hearing services during community-based screening camps to assess whether they had attended their referral and reasons for non-attendance. Semi-structured interviews were conducted with 23 caregivers of children who did not take up their referral to explore in-depth the reasons for non-uptake. In addition, 15 stakeholders were interviewed. Thematic analysis of the interview data was conducted and emerging trends were analysed. Referral uptake was very low with only 5 out of 150 (3%) children attending. Seven main interacting themes for non-uptake of referral were identified in the semi-structured interviews: location of the hospital, lack of transport, other indirect costs of seeking care, fear and uncertainty about the referral hospital, procedural problems within the camps, awareness and understanding of hearing loss, and lack of visibility and availability of services. This study has highlighted a range of interacting challenges faced by families in accessing ear and hearing services in this setting. Understanding these context specific barriers to non-uptake of ear and hearing services is important for designing appropriate interventions to increase uptake.

Sources of DPOAEs revealed by suppression experiments, inverse fast Fourier transforms, and SFOAEs in impaired ears

NASA Astrophysics Data System (ADS)

Konrad-Martin, Dawn; Neely, Stephen T.; Keefe, Douglas H.; Dorn, Patricia A.; Cyr, Emily; Gorga, Michael P.

2002-04-01

DPOAE sources are modeled by intermodulation distortion generated near the f2 place and a reflection of this distortion near the DP place. In a previous paper, inverse fast Fourier transforms (IFFTs) of DPOAE filter functions in normal ears were consistent with this model [Konrad-Martin et al., J. Acoust. Soc. Am. 109, 2862-2879 (2001)]. In the present article, similar measurements were made in ears with specific hearing-loss configurations. It was hypothesized that hearing loss at f2 or DP frequencies would influence the relative contributions to the DPOAE from the corresponding basilar membrane places, and would affect the relative magnitudes of SFOAEs at frequencies equal to f2 and fDP. DPOAEs were measured with f2=4 kHz, f1 varied, and a suppressor near fDP. L2 was 25-55 dB SPL (L1=L2+10 dB). SFOAEs were measured at f2 and at 2.7 kHz (the average fDP produced by the f1 sweep) for stimulus levels of 20-60 dB SPL. SFOAE results supported predictions of the pattern of amplitude differences between SFOAEs at 4 and 2.7 kHz for sloping losses, but did not support predictions for the rising- and flat-loss categories. Unsuppressed IFFTs for rising losses typically had one peak. IFFTs for flat or sloping losses typically have two or more peaks; later peaks were more prominent in ears with sloping losses compared to normal ears. Specific predictions were unambiguously supported by the results for only four of ten cases, and were generally supported in two additional cases. Therefore, the relative contributions of the two DPOAE sources often were abnormal in impaired ears, but not always in the predicted manner.

Reasons for low uptake of referrals to ear and hearing services for children in Malawi

PubMed Central

Mulwafu, Wakisa; Thindwa, Richard; Zuurmond, Maria; Polack, Sarah

2017-01-01

Background Early detection and appropriate intervention for children with hearing impairment is important for maximizing functioning and quality of life. The lack of ear and hearing services in low income countries is a significant challenge, however, evidence suggests that even where such services are available, and children are referred to them, uptake is low. The aim of this study was to assess uptake of and barriers to referrals to ear and hearing services for children in Thyolo District, Malawi. Methods This was a mixed methods study. A survey was conducted with 170 caregivers of children who were referred for ear and hearing services during community-based screening camps to assess whether they had attended their referral and reasons for non-attendance. Semi-structured interviews were conducted with 23 caregivers of children who did not take up their referral to explore in-depth the reasons for non-uptake. In addition, 15 stakeholders were interviewed. Thematic analysis of the interview data was conducted and emerging trends were analysed. Results Referral uptake was very low with only 5 out of 150 (3%) children attending. Seven main interacting themes for non-uptake of referral were identified in the semi-structured interviews: location of the hospital, lack of transport, other indirect costs of seeking care, fear and uncertainty about the referral hospital, procedural problems within the camps, awareness and understanding of hearing loss, and lack of visibility and availability of services. Conclusion This study has highlighted a range of interacting challenges faced by families in accessing ear and hearing services in this setting. Understanding these context specific barriers to non-uptake of ear and hearing services is important for designing appropriate interventions to increase uptake. PMID:29261683

Ear molding in newborn infants with auricular deformities.

PubMed

Byrd, H Steve; Langevin, Claude-Jean; Ghidoni, Lorraine A

2010-10-01

A review of a single physician's experience in managing over 831 infant ear deformities (488 patients) is presented. The authors' methods of molding have advanced from the use of various tapes, glues, and stents, to a comprehensive yet simple system that shapes the antihelix, the triangular fossa, the helical rim, and the overly prominent conchal-mastoid angle (EarWell Infant Ear Correction System). The types of deformities managed, and their relative occurrence, are as follows: (1) prominent/cup ear, 373 ears (45 percent); (2) lidding/lop ear, 224 ears (27 percent); (3) mixed ear deformities, 83 ears (10 percent) (all had associated conchal crus); (4) Stahl's ear, 66 ears (8 percent); (5) helical rim abnormalities, 58 ears (7 percent); (6) conchal crus, 25 ears (3 percent); and (7) cryptotia, two ears (0.2 percent). Bilateral deformities were present in 340 patients (70 percent), with unilateral deformities in 148 patients (30 percent). Fifty-eight infant ears (34 patients) were treated using the final version of the EarWell Infant Ear Correction System with a success rate exceeding 90 percent (good to excellent results). The system was found to be most successful when begun in the first week of the infant's life. When molding was initiated after 3 weeks from birth, only approximately half of the infants had a good response. Congenital ear deformities are common and only approximately 30 percent self-correct. These deformities can be corrected by initiating appropriate molding in the first week of life. Neonatal molding reduces the need for surgical correction with results that often exceed what can be achieved with the surgical alternative.

Effect of target-masker similarity on across-ear interference in a dichotic cocktail-party listening task.

PubMed

Brungart, Douglas S; Simpson, Brian D

2007-09-01

Similarity between the target and masking voices is known to have a strong influence on performance in monaural and binaural selective attention tasks, but little is known about the role it might play in dichotic listening tasks with a target signal and one masking voice in the one ear and a second independent masking voice in the opposite ear. This experiment examined performance in a dichotic listening task with a target talker in one ear and same-talker, same-sex, or different-sex maskers in both the target and the unattended ears. The results indicate that listeners were most susceptible to across-ear interference with a different-sex within-ear masker and least susceptible with a same-talker within-ear masker, suggesting that the amount of across-ear interference cannot be predicted from the difficulty of selectively attending to the within-ear masking voice. The results also show that the amount of across-ear interference consistently increases when the across-ear masking voice is more similar to the target speech than the within-ear masking voice is, but that no corresponding decline in across-ear interference occurs when the across-ear voice is less similar to the target than the within-ear voice. These results are consistent with an "integrated strategy" model of speech perception where the listener chooses a segregation strategy based on the characteristics of the masker present in the target ear and the amount of across-ear interference is determined by the extent to which this strategy can also effectively be used to suppress the masker in the unattended ear.

Method for the measurement of media player use

NASA Astrophysics Data System (ADS)

Webb, Graham

There has been ongoing concern that prolonged use of MP3 players can lead to noise-induced hearing loss. Acoustic exposure is the product of intensity and duration of exposure. Previous work has utilised measurements of maximum headphone output and output during listening tests to determine acoustic intensity; whilst duration of use is currently assessed with questionnaires and interviews. The subjective nature of these latter methods has led to a wide variation in figures for device use, restricting the scope of media player risk assessment. A need was therefore identified for an improved method of acquiring data of users' listening habits. This need was addressed with the design of a new data-logging device that discretely measures voltage output from the media player, whilst in use. A calibration method is proposed to implement the headphone transfer function into the data-logger, to relate output voltage to exposed pressure. It is proposed that the headphone transfer function is measured using an acoustic manikin, representative of the population of interest. The real ear measurement is put forward as an appropriate tool for validating results gained using this approach. A data-logger was designed and a proof of concept has been demonstrated in a software program written for this purpose. The proposed method has the advantages that an objective measurement can be made of the user's natural listening habits, over a long period of time, with a resolution comparable to personal acoustic dosimetry. A number of practical steps are required to further this work before data can be collected. A software graphic equaliser was used to implement the transfer function, but the chosen filter topology gave an unsatisfactory response, an investigation is required for further work. The device requires migration to hardware and the experimental calibration and validation of the system are also required. The worldwide population of MP3 player users is in the region of hundreds of millions of people. The relationship between user and device is becoming closer and portable music technology is becoming ubiquitous, permitting extended listening durations. There is therefore a strong need to continue this field of research, to increase understanding of the risks of this aspect of recreational noise.

Otitis

MedlinePlus

Ear infection; Infection - ear ... of the ear. The condition can be: Acute ear infection. Starts suddenly and lasts for a short period of time. It is often painful. Chronic ear infection. Occurs when the ear infection does not go ...

Evaluation of Two Circumaural Earphones for Audiometry.

PubMed

Smull, Clae C; Madsen, Brandon; Margolis, Robert H

2018-05-08

The Sennheiser HDA 200 earphone, a standard circumaural earphone used in audiometry for many years, is out of production and is replaced by the RadioEar DD450. The Sennheiser HD 280 Pro earphone is a consumer product that has characteristics that may be suitable for audiometry and may be a low-cost alternative to the DD450. The DD450 and HD 280 Pro earphones were compared with the HDA 200 for use in audiometry. RadioEar DD450 and Sennheiser HD 280 Pro earphones were evaluated for reference equivalent threshold sound pressure levels (RETSPLs), ambient-noise attenuation, and occlusion effects. Audiometric thresholds measured on a group of normal-hearing adults were used to determine RETSPLs. Ambient-noise attenuation was determined by measuring the sound pressure in the ear canal produced by a broadband signal from a loudspeaker with and without occlusion by the earphone. Acoustic occlusion effects were determined by measuring the ear-canal sound pressure produced by a bone-conducted source with and without occlusion by the earphone. The results were compared with measurements obtained from the HDA 200 earphone. Audiometric thresholds obtained using the DD450 earphone did not differ from those obtained with the HDA 200 earphones, indicating that the HDA 200 RETSPLs provided in the audiometer standards (ANSI S3.6-2010; ISO 389-8-2004) are transferable to the DD450. New RETSPLs for the HD 280 Pro earphone were determined from the threshold measurements. Ambient-noise attenuation provided by the DD450 was equivalent to the attenuation provided by the HDA 200. The HD 280 Pro provided less ambient-noise attenuation than the other circumaural earphones, but more than the supra-aural earphones commonly used in audiometry. The DD450 produced an occlusion effect 5 dB larger than that of the HDA 200 at 0.25 and 0.5 kHz; both earphones produced negligible occlusion effects at higher frequencies. The HD 280 Pro produced larger occlusion effects in the low frequencies than the other two earphones, with negligible occlusion effects at 1.0 kHz and above. The HDA 200 RETSPLs are transferable to the DD450. Ambient-noise attenuation and occlusion effects are similar for these two earphones. RETSPLs for the HD 280 Pro are provided. The HD 280 Pro has less ambient-noise attenuation and larger occlusion effects than the DD450 but is a viable low-cost alternative.

Evolution of the vestibulo-ocular system

NASA Technical Reports Server (NTRS)

Fritzsch, B.

1998-01-01

The evolutionary and developmental changes in the eye muscle innervation, the inner ear, and the vestibulo-ocular reflex are examined. Three eye muscle patterns, based on the innervation by distinct ocular motoneurons populations, can be identified: a lamprey, an elasmobranch, and a bony fish/tetrapod pattern. Four distinct patterns of variation in the vestibular system are described: a hagfish pattern, a lamprey pattern, an elasmobranch pattern, and a bony fish/tetrapod pattern. Developmental data suggest an influence of the hindbrain on ear pattern formation, thus potentially allowing a concomitant change of eye muscle innervation and ear variation. The connections between the ear and the vestibular nuclei and between the vestibular nuclei and ocular motoneurons are reviewed, and the role of neurotrophins for pattern specification is discussed. Three patterns are recognized in central projections: a hagfish pattern, a lamprey pattern, and a pattern for jawed vertebrates. Second-order connections show both similarities and differences between distantly related species such as lampreys and mammals. For example, elasmobranchs lack an internuclear system, which is at best poorly developed in lampreys. It is suggested that the vestibulo-ocular system shows only a limited degree of variation because of the pronounced functional constraints imposed on it.

Computational modeling of the generation and propagation of distortion products in the inner ear

NASA Astrophysics Data System (ADS)

Bowling, Thomas; Wen, Haiqi; Meaud, Julien

2018-05-01

Distortion product otoacoustic emissions are used in both clinical and research settings to assess cochlear function although there are still questions for how the distortion products propagate in the cochlea from their generation location to the middle ear. Here, a physiologically based computational model of the gerbil ear is used to investigate distortion product propagation. The fluid is modeled in three dimensions and includes two ducts. Simulations of the distortion products in the cochlear fluid pressure and basilar membrane are compared with published experimental data. Model results are consistent with measurements from Ren and colleagues which indicated that the intracochlear distortion product is dominated by a forward traveling wave at a low primary frequency ratio, although backward traveling waves become apparent when other ratios are considered. The magnitude and phase of both basilar membrane and spatial variations of the distortion product fluid pressure are qualitatively similar to the expected response of a slowly propagating backward traveling wave. These results combined suggest that distortion products propagate primarily as a slow wave both when the cochlea is driven by intracochlear sources and an acoustic stimulus in the ear canal.

Design of a dynamic sensor inspired by bat ears

NASA Astrophysics Data System (ADS)

Müller, Rolf; Pannala, Mittu; Reddy, O. Praveen K.; Meymand, Sajjad Z.

2012-09-01

In bats, the outer ear shapes act as beamforming baffles that create a spatial sensitivity pattern for the reception of the biosonar signals. Whereas technical receivers for wave-based signals usually have rigid geometries, the outer ears of some bat species, such as horseshoe bats, can undergo non-rigid deformations as a result of muscular actuation. It is hypothesized that these deformations provide the animals with a mechanism to adapt their spatial hearing sensitivity on short, sub-second time scales. This biological approach could be of interest to engineering as an inspiration for the design of beamforming devices that combine flexibility with parsimonious implementation. To explore this possibility, a biomimetic dynamic baffle was designed based on a simple shape overall geometry based on an average bat ear. This shape was augmented with three different biomimetic local shape features, a ridge on its exposed surface as well as a flap and an incision along its rim. Dynamic non-rigid deformations of the shape were accomplished through a simple actuation mechanism based on linear actuation inserted at a single point. Despite its simplicity, the prototype device was able to reproduce the dynamic functional characteristics that have been predicted for its biological paragon in a qualitative fashion.

Neural effects of cognitive control load on auditory selective attention

PubMed Central

Sabri, Merav; Humphries, Colin; Verber, Matthew; Liebenthal, Einat; Binder, Jeffrey R.; Mangalathu, Jain; Desai, Anjali

2014-01-01

Whether and how working memory disrupts or alters auditory selective attention is unclear. We compared simultaneous event-related potentials (ERP) and functional magnetic resonance imaging (fMRI) responses associated with task-irrelevant sounds across high and low working memory load in a dichotic-listening paradigm. Participants performed n-back tasks (1-back, 2-back) in one ear (Attend ear) while ignoring task-irrelevant speech sounds in the other ear (Ignore ear). The effects of working memory load on selective attention were observed at 130-210 msec, with higher load resulting in greater irrelevant syllable-related activation in localizer-defined regions in auditory cortex. The interaction between memory load and presence of irrelevant information revealed stronger activations primarily in frontal and parietal areas due to presence of irrelevant information in the higher memory load. Joint independent component analysis of ERP and fMRI data revealed that the ERP component in the N1 time-range is associated with activity in superior temporal gyrus and medial prefrontal cortex. These results demonstrate a dynamic relationship between working memory load and auditory selective attention, in agreement with the load model of attention and the idea of common neural resources for memory and attention. PMID:24946314

Cell density and N-cadherin interactions regulate cell proliferation in the sensory epithelia of the inner ear.

PubMed

Warchol, Mark E

2002-04-01

Sensory hair cells in the inner ears of nonmammalian vertebrates can regenerate after injury. In many species, replacement hair cells are produced by the proliferation of epithelial supporting cells. Thus, the ability of supporting cells to undergo renewed proliferation is a key determinant of regenerative ability. The present study used cultures of isolated inner ear sensory epithelia to identify cellular signals that regulate supporting cell proliferation. Small pieces of sensory epithelia from the chicken utricle were cultured in glass microwells. Under those conditions, cell proliferation was inversely related to local cell density. The signaling molecules N-cadherin, beta-catenin, and focal adhesion kinase were immunolocalized in the cultured epithelial cells, and high levels of phosphotyrosine immunoreactivity were present at cell-cell junctions and focal contacts of proliferating cells. Binding of microbeads coated with a function-blocking antibody to N-cadherin inhibited ongoing proliferation. The growth of epithelial cells was also affected by the density of extracellular matrix molecules. The results suggest that cell density, cell-cell contact, and the composition of the extracellular matrix may be critical influences on the regulation of sensory regeneration in the inner ear.

The Relationship between Binaural Benefit and Difference in Unilateral Speech Recognition Performance for Bilateral Cochlear Implant Users

PubMed Central

Yoon, Yang-soo; Li, Yongxin; Kang, Hou-Yong; Fu, Qian-Jie

2011-01-01

Objective The full benefit of bilateral cochlear implants may depend on the unilateral performance with each device, the speech materials, processing ability of the user, and/or the listening environment. In this study, bilateral and unilateral speech performances were evaluated in terms of recognition of phonemes and sentences presented in quiet or in noise. Design Speech recognition was measured for unilateral left, unilateral right, and bilateral listening conditions; speech and noise were presented at 0° azimuth. The “binaural benefit” was defined as the difference between bilateral performance and unilateral performance with the better ear. Study Sample 9 adults with bilateral cochlear implants participated. Results On average, results showed a greater binaural benefit in noise than in quiet for all speech tests. More importantly, the binaural benefit was greater when unilateral performance was similar across ears. As the difference in unilateral performance between ears increased, the binaural advantage decreased; this functional relationship was observed across the different speech materials and noise levels even though there was substantial intra- and inter-subject variability. Conclusions The results indicate that subjects who show symmetry in speech recognition performance between implanted ears in general show a large binaural benefit. PMID:21696329

Hearing loss and the central auditory system: Implications for hearing aids

NASA Astrophysics Data System (ADS)

Frisina, Robert D.

2003-04-01

Hearing loss can result from disorders or damage to the ear (peripheral auditory system) or the brain (central auditory system). Here, the basic structure and function of the central auditory system will be highlighted as relevant to cases of permanent hearing loss where assistive devices (hearing aids) are called for. The parts of the brain used for hearing are altered in two basic ways in instances of hearing loss: (1) Damage to the ear can reduce the number and nature of input channels that the brainstem receives from the ear, causing plasticity of the central auditory system. This plasticity may partially compensate for the peripheral loss, or add new abnormalities such as distorted speech processing or tinnitus. (2) In some situations, damage to the brain can occur independently of the ear, as may occur in cases of head trauma, tumors or aging. Implications of deficits to the central auditory system for speech perception in noise, hearing aid use and future innovative circuit designs will be provided to set the stage for subsequent presentations in this special educational session. [Work supported by NIA-NIH Grant P01 AG09524 and the International Center for Hearing & Speech Research, Rochester, NY.

Into the dark: patterns of middle ear adaptations in subterranean eulipotyphlan mammals

NASA Astrophysics Data System (ADS)

Koyabu, Daisuke; Hosojima, Misato; Endo, Hideki

2017-09-01

Evolution of the middle ear ossicles was a key innovation for mammals, enhancing the transmission of airborne sound. Radiation into various habitats from a terrestrial environment resulted in diversification of the auditory mechanisms among mammals. However, due to the paucity of phylogenetically controlled investigations, how middle ear traits have diversified with functional specialization remains unclear. In order to identify the respective patterns for various lifestyles and to gain insights into fossil forms, we employed a high-resolution tomography technique and compared the middle ear morphology of eulipotyphlan species (moles, shrews and hedgehogs), a group that has radiated into various environments, such as terrestrial, aquatic and subterranean habitats. Three-dimensional geometric morphometric analysis was conducted within a phylogenetically controlled framework. Quantitative shapes were found to strongly reflect the degree of subterranean lifestyle and weakly involve phylogeny. Our analyses demonstrate that subterranean adaptation should include a relatively shorter anterior process of the malleus, an enlarged incus, an enlarged stapes footplate and a reduction of the orbicular apophysis. These traits arguably allow improving low-frequency sound transmission at low frequencies and inhibiting the low-frequency noise which disturbs the subterranean animals in hearing airborne sounds.

Genetic evidence for conserved non-coding element function across species–the ears have it

PubMed Central

Turner, Eric E.; Cox, Timothy C.

2014-01-01

Comparison of genomic sequences from diverse vertebrate species has revealed numerous highly conserved regions that do not appear to encode proteins or functional RNAs. Often these “conserved non-coding elements,” or CNEs, can direct gene expression to specific tissues in transgenic models, demonstrating they have regulatory function. CNEs are frequently found near “developmental” genes, particularly transcription factors, implying that these elements have essential regulatory roles in development. However, actual examples demonstrating CNE regulatory functions across species have been few, and recent loss-of-function studies of several CNEs in mice have shown relatively minor effects. In this Perspectives article, we discuss new findings in “fancy” rats and Highland cattle demonstrating that function of a CNE near the Hmx1 gene is crucial for normal external ear development and when disrupted can mimic loss-of function Hmx1 coding mutations in mice and humans. These findings provide important support for conserved developmental roles of CNEs in divergent species, and reinforce the concept that CNEs should be examined systematically in the ongoing search for genetic causes of human developmental disorders in the era of genome-scale sequencing. PMID:24478720

Audiological characteristics of infants with abnormal transient evoked otoacoustic emission and normal auditory brainstem response.

PubMed

Huang, Lihui; Han, Demin; Guo, Ying; Liu, Sha; Cui, Xiaoyan; Mo, Lingyan; Qi, Beier; Cai, Zhenghua; Liu, Hui; En, Hui; Guo, Liansheng

2008-10-01

Audiological characteristics were investigated in 81 ears of 53 infants with abnormal transient evoked otoacoustic emission (TEOAE) and normal auditory brainstem response (ABR). The relationship between ABR and other hearing testing methods, including 40Hz auditory event-related potential (40Hz-AERP), auditory steady state response (ASSR), distortion product otoacoustic emission (DPOAE), tympanometry, and acoustic reflex, was analyzed. Of the 81 ears, 18 ears (22.2%) were normal, while 63 ears (77.8%) were abnormal according to the tests. Testing of the 40 Hz AERP (36 ears) and ASSR (45 ears) revealed that 14 ears (38.9%) and 27 ears (60.0%) were abnormal, respectively. Testing of DPOAE in 68 ears revealed that 50 ears (73.5%) were abnormal. Testing of tympanometry in 50 ears and acoustic reflex in 47 ears revealed that 9 ears (18%) and 27 ears (57.4%) were abnormal, respectively. The present data suggests that the hearing of infants cannot be sufficiently evaluated with ABR only and that it must be evaluated with integrative audiological testing methods.

Useless hearing in male Emblemasoma auditrix (Diptera, Sarcophagidae)--a case of intralocus sexual conflict during evolution of a complex sense organ?

PubMed

Lakes-Harlan, Reinhard; Devries, Thomas; Stölting, Heiko; Stumpner, Andreas

2014-01-01

Sensory modalities typically are important for both sexes, although sex-specific functional adaptations may occur frequently. This is true for hearing as well. Consequently, distinct behavioural functions were identified for the different insect hearing systems. Here we describe a first case, where a trait of an evolutionary novelty and a highly specialized hearing organ is adaptive in only one sex. The main function of hearing of the parasitoid fly Emblemasoma auditrix is to locate the host, males of the cicada species Okanagana rimosa, by their calling song. This task is performed by female flies, which deposit larvae into the host. We show that male E. auditrix possess a hearing sense as well. The morphology of the tympanal organ of male E. auditrix is rather similar to the female ear, which is 8% broader than the male ear. In both sexes the physiological hearing threshold is tuned to 5 kHz. Behavioural tests show that males are able to orient towards the host calling song, although phonotaxis often is incomplete. However, despite extensive observations in the field and substantial knowledge of the biology of E. auditrix, no potentially adaptive function of the male auditory sense has been identified. This unique hearing system might represent an intralocus sexual conflict, as the complex sense organ and the behavioural relevant neuronal network is adaptive for only one sex. The correlated evolution of the sense organ in both sexes might impose substantial constraints on the sensory properties of the ear. Similar constraints, although hidden, might also apply to other sensory systems in which behavioural functions differ between sexes.

Middle ear impedance measurements in large vestibular aqueduct syndrome.

PubMed

Bilgen, Cem; Kirkim, Günay; Kirazli, Tayfun

2009-06-01

To assess the effect of inner ear pressure on middle ear impedance in patients with large vestibular aqueduct syndrome (LVAS). Data from admittance tympanometry and multifrequency tympanometry on 8 LVAS patients and control subjects were studied. Static acoustic compliance (SAC) values for the ears with stable sensorineural hearing loss (SNHL) were within the limits of the mean values of control groups except for two ears. The resonance frequency (RF) values of the ears with stable SNHL were lower than the mean values of control groups except for three ears. SAC values for the two ears with fluctuating SNHL were lower and the RF values were higher than the mean values of control groups. Decreased SAC values and increased RF values found in the ears with fluctuating SNHL might be an indirect indicator of increased inner ear pressure, while low RF values in the ears with stable SNHL might reflect the decreased inner ear impedance.

Localization of efferent neurotransmitters in the inner ear of the homozygous Bronx waltzer mutant mouse.

PubMed

Kong, W J; Scholtz, A W; Hussl, B; Kammen-Jolly, K; Schrott-Fischer, A

2002-05-01

Naturally occurring mutant mice provide an excellent model for the study of genetic malformations of the inner ear. Mice homozygous for the Bronx waltzer (bv/bv) mutation are severely hearing impaired or deaf and exhibit a 'waltzing' gait. Functional aspects of cochlear and vestibular efferents in the bv/bv mutant mouse are not well known. The present study was designed to evaluate several candidates of efferent neurotransmitters or neuromodulators including choline acetyltransferase (ChAT), gamma-aminobutyric acid (GABA), and calcitonin gene-related peptide (CGRP) in the inner ear of the bv/bv mutant mouse. Ultrastructural investigations at both light and electron microscopic level were performed. Ultrastructural morphologic evaluations of the cochlea and the vestibular end-organs were also undertaken. It is demonstrated that ChAT, GABA and CGRP immunoreactivities are present in the cochlea and in vestibular end-organs of bv/bv mutant mice. In the organ of Corti, immunoreactivity of ChAT, GABA and CGRP is confined to the inner spiral fibers, tunnel-crossing fibers, and the vesiculated nerve endings synapsing with outer hair cells. Interestingly, immunoreactivity was detectable even where inner hair cells appeared missing. Results also revealed malformations of the outer hair cells with synaptic contacts to efferent nerve endings consistently intact. In the neurosensory epithelia of the vestibular end-organs, the presence of ChAT, GABA, and CGRP immunoreactivity was localized at the vestibular efferents, with the exception of the macula of saccule. In one 8-month-old macula of utricle where the depletion of hair cells appeared highest, ChAT immunostaining was still discernible. Ultrastructural investigation demonstrated that vesiculated efferent nerve endings make synaptic contact with the outer hair cells in the organ of Corti and with type II hair cells in the vestibular end-organs. The present study provides further support that the efferent system in the bv/bv mutant inner ear is morphologically as well as functionally mature. These findings also demonstrate that if and when the onset of efferent degeneration in the bv/bv mutant inner ear occurs, it transpires subsequent to pathological conditions in the hair cells. The present findings give further indication that the efferent systems of the bv/bv mutant inner ear are independent of the afferent systems in many aspects including development, maturation as well as degeneration.

Avian dark cells

NASA Technical Reports Server (NTRS)

Hara, J.; Plymale, D. R.; Shepard, D. L.; Hara, H.; Garry, Robert F.; Yoshihara, T.; Zenner, Hans-Peter; Bolton, M.; Kalkeri, R.; Fermin, Cesar D.

2002-01-01

Dark cells (DCs) of mammalian and non-mammalian species help to maintain the homeostasis of the inner ear fluids in vivo. Although the avian cochlea is straight and the mammalian cochlea is coiled, no significant difference in the morphology and/or function of mammalian and avian DCs has been reported. The mammalian equivalent of avian DCs are marginal cells and are located in the stria vascularis along a bony sheet. Avian DCs hang free from the tegmentum vasculosum (TV) of the avian lagena between the perilymph and endolymph. Frame averaging was used to image the fluorescence emitted by several fluorochromes applied to freshly isolated dark cells (iDCs) from chickens (Gallus domesticus) inner ears. The viability of iDCs was monitored via trypan blue exclusion at each isolation step. Sodium Green, BCECF-AM, Rhodamine 123 and 9-anthroyl ouabain molecules were used to test iDC function. These fluorochromes label iDCs ionic transmembrane trafficking function, membrane electrogenic potentials and Na+/K+ ATPase pump's activity. Na+/K+ ATPase pump sites, were also evaluated by the p-nitrophenyl phosphatase reaction. These results suggest that iDCs remain viable for several hours after isolation without special culturing requirements and that the number and functional activity of Na+/K+ ATPase pumps in the iDCs were indistinguishable from in vivo DCs. Primary cultures of freshly iDCs were successfully maintained for 28 days in plastic dishes with RPMI 1640 culture medium. The preparation of iDCs overcomes the difficulty of DCs accessability in vivo and the unavoidable contamination that rupturing the inner ear microenvironments induces.

Nonsurgical correction of congenital ear abnormalities in the newborn: Case series.

PubMed

Smith, Wg; Toye, Jw; Reid, A; Smith, Rw

2005-07-01

To determine whether a simple, nonsurgical treatment for congenital ear abnormalities (lop-ear, Stahl's ear, protruding ear, cryptotia) improved the appearance of ear abnormalities in newborns at six weeks of age. This is a descriptive case series. All newborns with identified abnormalities were referred by their family physician to one paediatrician (WGS) in a small level 2 perinatal centre. The ears were waxed and taped in a standard manner within 10 days of birth. Pictures were taken before taping and at the end of taping (one month). All patients and pictures were assessed by one plastic surgeon (JWT) at six weeks of age and scored using a standard scoring system. A telephone survey of the nontreatment group was conducted. The total number of ears assessed was 90. Of this total, 69 ears were taped and fully evaluated in the study (77%). The refusal rate was 23%. In the treatment group, 59% had lop-ear, 19% had Stahl's ear, 17% had protruding ear and 3% had cryptotia. Overall correction (excellent/improved) for the treatment group was 90% (100% for lop-ear, 100% for Stahl's ear, 67% for protruding ear and 0% for cryptotia). In the nontreatment (refusal) group, 67% of the ears failed to correct spontaneously. No complications were recognized by the authors or parents by six weeks. The percentage of newborns in one year in the perinatal centre with recognized ear abnormalities was 6% (90 of 1600). A simple, nonsurgical treatment in a Caucasian population appeared to be very effective in correcting congenital ear abnormalities with no complications and high patient/parent satisfaction.

High frequency bone conduction auditory evoked potentials in the guinea pig: Assessing cochlear injury after ossicular chain manipulation.

PubMed

Bergin, M J; Bird, P A; Vlajkovic, S M; Thorne, P R

2015-12-01

Permanent high frequency (>4 kHz) sensorineural hearing loss following middle ear surgery occurs in up to 25% of patients. The aetiology of this loss is poorly understood and may involve transmission of supra-physiological forces down the ossicular chain to the cochlea. Investigating the mechanisms of this injury using animal models is challenging, as evaluating cochlear function with evoked potentials is confounded when ossicular manipulation disrupts the normal air conduction (AC) pathway. Bone conduction (BC) using clinical bone vibrators in small animals is limited by poor transducer output at high frequencies sensitive to trauma. The objectives of the present study were firstly to evaluate a novel high frequency bone conduction transducer with evoked auditory potentials in a guinea pig model, and secondly to use this model to investigate the impact of middle ear surgical manipulation on cochlear function. We modified a magnetostrictive device as a high frequency BC transducer and evaluated its performance by comparison with a calibrated AC transducer at frequencies up to 32 kHz using the auditory brainstem response (ABR), compound action potential (CAP) and summating potential (SP). To mimic a middle ear traumatising stimulus, a rotating bur was brought in to contact with the incudomalleal complex and the effect on evoked cochlear potentials was observed. BC-evoked potentials followed the same input-output function pattern as AC potentials for all ABR frequencies. Deterioration in CAP and SP thresholds was observed after ossicular manipulation. It is possible to use high frequency BC to evoke responses from the injury sensitive basal region of the cochlea and so not rely on AC with the potential confounder of conductive hearing loss. Ongoing research explores how these findings evolve over time, and ways in which injury may be reduced and the cochlea protected during middle ear surgery. Copyright © 2015 Elsevier B.V. All rights reserved.

Sonographic Measurement of Fetal Ear Length in Turkish Women with a Normal Pregnancy

PubMed Central

Özdemir, Mucize Eriç; Uzun, Işıl; Karahasanoğlu, Ayşe; Aygün, Mehmet; Akın, Hale; Yazıcıoğlu, Fehmi

2014-01-01

Background: Abnormal fetal ear length is a feature of chromosomal disorders. Fetal ear length measurement is a simple measurement that can be obtained during ultrasonographic examinations. Aims: To develop a nomogram for fetal ear length measurements in our population and investigate the correlation between fetal ear length, gestational age, and other standard fetal biometric measurements. Study Design: Cohort study. Methods: Ear lengths of the fetuses were measured in normal singleton pregnancies. The relationship between gestational age and fetal ear length in millimetres was analysed by simple linear regression. In addition, the correlation of fetal ear length measurements with biparietal diameter, head circumference, abdominal circumference, and femur length were evaluated.Ear length measurements were obtained from fetuses in 389 normal singleton pregnancies ranging between 16 and 28 weeks of gestation. Results: A nomogram was developed by linear regression analysis of the parameters ear length and gestational age. Fetal ear length (mm) = y = (1.348 X gestational age)−12.265), where gestational ages is in weeks. A high correlation was found between fetal ear length and gestational age, and a significant correlation was also found between fetal ear length and the biparietal diameter (r=0.962; p<0.001). Similar correlations were found between fetal ear length and head circumference, and fetal ear length and femur length. Conclusion: The results of this study provide a nomogram for fetal ear length. The study also demonstrates the relationship between ear length and other biometric measurements. PMID:25667783

Oval window transport of Gd-dOTA from rat middle ear to vestibulum and scala vestibuli visualized by in vivo magnetic resonance imaging.

PubMed

Zou, Jing; Poe, Dennis; Ramadan, Usama Abo; Pyykkö, Ilmari

2012-02-01

We tested our hypothesis that the oval window (OW) potentially functions as a route to carry substances from the middle ear to the vestibulum and then the scala vestibuli through the annular ligament across the stapediovestibular joint. Gd-DOTA was either injected into the lateral attic compartment of rats with a high-performance polyimide tube in a selective OW delivery group, or administered to the middle ear cavity of two groups of rats in which the OW was either sealed or not sealed. The dynamic uptake of Gd-DOTA in the inner ear was visualized with a 4.7-T magnetic resonance imaging machine. In the selective OW delivery group, Gd-DOTA appeared in the vestibulum and in the basal turn of the scala vestibuli but not in the scala tympani on T1-weighted images acquired at 10 minutes after Gd-DOTA administration (the earliest available time point of magnetic resonance imaging). In the sealed-OW group, immediate uptake of Gd-DOTA was absent in the vestibulum and scala vestibuli. Measurement of the signal ratio of the vestibulum to that of the scala tympani showed that selective OW delivery induced the greatest signal ratio and that sealing of the OW induced the lowest signal ratio. The OW is a genuine and efficient pathway to transport Gd-DOTA from the middle ear to the vestibulum.

Eustachian Tube Function.

PubMed

Ars, Bernard; Dirckx, Joris

2016-10-01

The fibrocartilaginous eustachian tube is part of a system of contiguous organs including the nose, palate, rhinopharynx, and middle ear cleft. The middle ear cleft consists of the tympanic cavity, which includes the bony eustachian tube (protympanum) and the mastoid gas cells system. The tympanic cavity and mastoid gas cells are interconnected and allow gaseous exchange and pressure regulation. The fibrocartilaginous eustachian tube is a complex organ consisting of a dynamic conduit with its mucosa, cartilage, surrounding soft tissue, peritubal muscles (ie, tensor and levator veli palatine, salpingopharyngeus and tensor tympani), and superior bony support (the sphenoid sulcus). Copyright © 2016 Elsevier Inc. All rights reserved.

The effects of V2 antagonist (OPC-31260) on endolymphatic hydrops.

PubMed

Takeda, Taizo; Sawada, Shoichi; Takeda, Setsuko; Kitano, Hiroya; Suzuki, Mikio; Kakigi, Akinobu; Takeuchi, Shunji

2003-08-01

In the present study, two experiments were performed to investigate the influence of OPC-31260 on experimentally induced endolymphatic hydrops in guinea pigs and the regulation of aquaporin-2 (AQP2) mRNA expression in the rat inner ear. In morphological studies, the increases in the ratios of the length of Reissner's membrane (IR-L) and the cross-sectional area of the scala media (IR-S) were quantitatively assessed among normal guinea pigs (normal ears) and three groups with hydropic ears: hydropic ears with no infusion (non-infusion hydropic ears), hydropic ears with an infusion of physiological saline into the scala tympani (saline-infused hydropic ears) and hydropic ears with infusion of 0.3% OPC-31260 into the scala tympani (OPC-infused hydropic ears). IR-Ls in the experimental groups were markedly larger than in the normal ear group, but there was no significant difference among the groups of non-infusion hydropic ears, saline-infused hydropic ears and OPC-infused hydropic ears. The IR-Ss of non-infusion hydropic ears and saline-infused hydropic ears (48.8-49.3%) were statistically different from that of normal ears (6.5%) (Dunnet multiple comparison test, P<0.01). However, IR-S of the OPC-infused hydropic ears (-14.8%) was significantly smaller than those of non-infusion hydropic ears and saline-infused hydropic ears (one-way ANOVA, P<0.01). In the quantitative polymerase chain reaction study, a comparison of the ratio of AQP2 and beta-actin mRNA (MAQP2/Mbeta-actin) was made between water-injected and OPC-31260-injected rats. An intravenous injection of OPC-31260 resulted in a significant decrease in MAQP2/Mbeta-actin both in the cochlea and in the endolymphatic sac (t-test, P<0.001). These results indicate that water homeostasis in the inner ear is regulated via the vasopressin-AQP2 system, and that the vasopressin type-2 antagonist OPC-31260 is a promising drug in the treatment of Meniere's disease.

Surgical management of polyotia.

PubMed

Pan, Bo; Qie, Shuyan; Zhao, Yanyong; Tang, Xiaojun; Lin, Lin; Yang, Qinghua; Zhuang, Hongxing; Jiang, Haiyue

2010-08-01

Polyotia is an extremely rare type of congenital external ear malformation, which is defined as an accessory ear that is large enough to resemble an additional pinna. The terms 'mirror ear' or 'accessory ear' are sometime used. We present our methods in correcting this malformation and summarise the aetiology. The posterior part of the polyotia may presents with a normal ear, a constricted ear or a microtic ear. Free auricular composite tissue transplantation was used to correct the constricted ear. Ear reconstruction was applied in cases of microtia. The anterior auricle was mainly used to form the tragus. 7 cases polyotia were treated between 2004 and 2008. After free auricular composite tissue transplantation the size of the constricted ear and the contralateral ear was similar. In microtia cases the reconstructed ears were natural looking and had a satisfactory three-dimensional contour. The extra tissue of the anterior ear was excised and the tragus was reconstructed. Through operative intervention tailored to the individual case natural-looking and symmetric ears were acquired. The aetiology of polyotia probably relates to abnormal migration of neural crest cell. Copyright 2009 British Association of Plastic, Reconstructive and Aesthetic Surgeons. Published by Elsevier Ltd. All rights reserved.

Clearance by the mucociliary system in 'simple chronic otitis media'.

PubMed

Hadas, E; Sadé, J

1979-08-01

This is a study of the rate of middle ear clearance in chronic otitis media and atelectatic ears. The clearance rate was measured with the aid of non-soluble saccharin, introduced into the middle ear through an existing perforation in 'chronic ears', or through a ventilating tube in atelectatic ears. Cholesteatomatous ears were excluded. Altogether 122 ears were examined and about two-thirds of the subjects felt the sweet taste in their mouths thereafter. The average time it took for the saccharin to be transported from the middle ear to the taste buds was 33' 22" minutes in non-infected (i.e. dry) chronic ears (38 patients or 66 per cent). Wet or infected ears with chronic otitis media (30 patients, or 58 per cent) showed a slower transport rate, averaging 54' 22" minutes--the difference was significant at the 0.01 level. 8 (63 per cent) of the atelectatic ears transported the saccharin at an average rate of 50' 25". This study demonstrated that most ears with 'simple' chronic otitis media and atelectatic ears have a patent eustachian tube and that their mucociliary system can transport foreign particles through it. When the ear is infected, transport tends to be slowed down.

Sound levels, hearing habits and hazards of using portable cassete players

NASA Astrophysics Data System (ADS)

Hellström, P.-A.; Axelsson, A.

1988-12-01

The maximum output sound pressure level ( SPL) from different types of portable cassette players (PCP's) and different headphones was analyzed by using KEMAR in one-third octave bands. The equivalent free-field dB(A) level (EqA-FFSL) was computed from the one-third octave bands corrected by the free-field to the eardrum transfer function. The dB(A) level varied between 104 dB from a low-cost PCP with supra-aural headphones (earphones with headbands and foam pads fitting against the pinna) to 126 dB from a high quality PCP with semi-aural headphones (small earphones without headbands to be used in the concha of the external ear). The cassette tapes used in this study were recorded with music, white noise, narrowband noise and pure tones. The equivalent and maximum SPL was measured in the ear canal (1 mm from eardrum) with the use of mini-microphones in 15 young subjects listening to pop music from PCP's at the highest level they considered comfortable. These SPL measurements corresponded to 112 dB(A) in free field. In a temporary threshold shift ( TTS) study, ten teenagers—four girls and six boys—listened to pop music for 1 h with PCP's at a level they enjoyed. The mean TTS value was 5-10 dB for frequencies between 1 and 8 kHz. In one subject the maximum TTS was 35 dB at 5-6 dB kHz. In order to acquire information about listening habits among youngsters using PCP's, 154 seventh and eighth graders (age 14-15) were interviewed. They used PCP's much less than expected during most of the year, but an increase was reported during the summer holidays.

Gravitoinertial force magnitude and direction influence head-centric auditory localization

NASA Technical Reports Server (NTRS)

DiZio, P.; Held, R.; Lackner, J. R.; Shinn-Cunningham, B.; Durlach, N.

2001-01-01

We measured the influence of gravitoinertial force (GIF) magnitude and direction on head-centric auditory localization to determine whether a true audiogravic illusion exists. In experiment 1, supine subjects adjusted computer-generated dichotic stimuli until they heard a fused sound straight ahead in the midsagittal plane of the head under a variety of GIF conditions generated in a slow-rotation room. The dichotic stimuli were constructed by convolving broadband noise with head-related transfer function pairs that model the acoustic filtering at the listener's ears. These stimuli give rise to the perception of externally localized sounds. When the GIF was increased from 1 to 2 g and rotated 60 degrees rightward relative to the head and body, subjects on average set an acoustic stimulus 7.3 degrees right of their head's median plane to hear it as straight ahead. When the GIF was doubled and rotated 60 degrees leftward, subjects set the sound 6.8 degrees leftward of baseline values to hear it as centered. In experiment 2, increasing the GIF in the median plane of the supine body to 2 g did not influence auditory localization. In experiment 3, tilts up to 75 degrees of the supine body relative to the normal 1 g GIF led to small shifts, 1--2 degrees, of auditory setting toward the up ear to maintain a head-centered sound localization. These results show that head-centric auditory localization is affected by azimuthal rotation and increase in magnitude of the GIF and demonstrate that an audiogravic illusion exists. Sound localization is shifted in the direction opposite GIF rotation by an amount related to the magnitude of the GIF and its angular deviation relative to the median plane.

Evaluation of appearance transfer and persistence in central face transplantation: a computer simulation analysis.

PubMed

Pomahac, Bohdan; Aflaki, Pejman; Nelson, Charles; Balas, Benjamin

2010-05-01

Partial facial allotransplantation is an emerging option in reconstruction of central facial defects, providing function and aesthetic appearance. Ethical debate partly stems from uncertainty surrounding identity aspects of the procedure. There is no objective evidence regarding the effect of donors' transplanted facial structures on appearance change of the recipients and its influence on facial recognition of donors and recipients. Full-face frontal view color photographs of 100 volunteers were taken at a distance of 150 cm with a digital camera (Nikon/DX80). Photographs were taken in front of a blue background, and with a neutral facial expression. Using image-editing software (Adobe-Photoshop-CS3), central facial transplantation was performed between participants. Twenty observers performed a familiar 'facial recognition task', to identify 40 post-transplant composite faces presented individually on the screen at a viewing distance of 60 cm, with an exposure time of 5s. Each composite face comprised of a familiar and an unfamiliar face to the observers. Trials were done with and without external facial features (head contour, hair and ears). Two variables were defined: 'Appearance Transfer' refers to transfer of donor's appearance to the recipient. 'Appearance Persistence' deals with the extent of recipient's appearance change post-transplantation. A t-test was run to determine if the rates of Appearance Transfer differed from Appearance Persistence. Average Appearance Transfer rate (2.6%) was significantly lower than Appearance Persistence rate (66%) (P<0.001), indicating that donor's appearance transfer to the recipient is negligible, whereas recipients will be identified the majority of the time. External facial features were important in facial recognition of recipients, evidenced by a significant rise in Appearance Persistence from 19% in the absence of external features to 66% when those features were present (P<0.01). This study may be helpful in the informed consent process of prospective recipients. It is beneficial for education of donors families and is expected to positively affect their decision to consent for facial tissue donation. Copyright (c) 2009 British Association of Plastic, Reconstructive and Aesthetic Surgeons. Published by Elsevier Ltd. All rights reserved.

Anomalies of the middle and inner ear.

PubMed

Rodriguez, Kimsey; Shah, Rahul K; Kenna, Margaret

2007-02-01

The development of the middle and inner ear highlights the intricacy of embryology. As early as 3 weeks after fertilization, the inner ear begins taking form. This process, along with development of the middle ear, continues throughout gestation. At birth, the middle ear, inner ear, and associated structures are almost adult size. An understanding of the embryologic development of the ear serves as a foundation for evaluating and managing congenital malformations of these structures. The focus of this article is the normal, abnormal, and arrested development of the middle and inner ear, with a clinical emphasis on malformed middle and inner ear structures and a discussion of associated syndromes.

40 CFR 211.203 - Definitions.

Code of Federal Regulations, 2012 CFR

2012-07-01

... entering the ear. This includes devices of which hearing protection may not be the primary function, but... -carrying case. (u) Primary Panel. The surface that is considered to be the front surface or that surface...

40 CFR 211.203 - Definitions.

Code of Federal Regulations, 2014 CFR

2014-07-01

... entering the ear. This includes devices of which hearing protection may not be the primary function, but... -carrying case. (u) Primary Panel. The surface that is considered to be the front surface or that surface...

40 CFR 211.203 - Definitions.

Code of Federal Regulations, 2013 CFR

2013-07-01

... entering the ear. This includes devices of which hearing protection may not be the primary function, but... -carrying case. (u) Primary Panel. The surface that is considered to be the front surface or that surface...

Genetics Home Reference: Alport syndrome

MedlinePlus

... particularly the organ of Corti, that transform sound waves into nerve impulses for the brain. Alterations in type IV collagen often result in abnormal inner ear function, which can lead to hearing loss. In the ...

Otoconia biogenesis, phylogeny, composition and functional attributes

NASA Technical Reports Server (NTRS)

Fermin, C. D.; Lychakov, D.; Campos, A.; Hara, H.; Sondag, E.; Jones, T.; Jones, S.; Taylor, M.; Meza-Ruiz, G.; Martin, D. S.

1998-01-01

This work consolidates data about these interesting organic crystals of vertebrate inner ears. It addresses 5 aspects of inner ear otoliths not completely understood to date: 1) embryological data that explains the formation of the crystals, 2) the significance of the organic and the inorganic phase of the otolith and the changing patterns of otoconia formation along the evolutionary tree, 3) otoliths contribution for detecting linear acceleration, 4) the effect that altered gravity and aminoglycosides have on the development and adult shape of the crystals, and the evolutionary significance of a changing shape of the crystals from primitive forms (lamprey) to high vertebrate birds and mammals is discussed, 5) functional attributes of the otolithic organs and morphological modifications of the otoliths by physical and chemical insults are presented with an extensive discussion of the most relevant literature published and available to us.

Systematic review of middle ear implants: do they improve hearing as much as conventional hearing AIDS?

PubMed

Tysome, James R; Moorthy, Ram; Lee, Ambrose; Jiang, Dan; O'Connor, Alec Fitzgerald

2010-12-01

A systematic review to determine whether middle ear implants (MEIs) improve hearing as much as hearing aids. Databases included MEDLINE, EMBASE, DARE, and Cochrane searched with no language restrictions from 1950 or the start date of each database. Initial search found 644 articles, of which 17 met the inclusion criteria of MEI in adults with a sensorineural hearing loss, where hearing outcomes and patient-reported outcome measures (PROMs) compared MEI with conventional hearing aids (CHAs). Study quality assessment included whether ethical approval was gained, the study was prospective, eligibility criteria specified, a power calculation made and appropriate controls, outcome measures, and analysis performed. Middle ear implant outcome analysis included residual hearing, complications, and comparison to CHA in terms of functional gain, speech perception in quiet and in noise, and validated PROM questionnaires. Because of heterogeneity of outcome measures, comparisons were made by structured review. The quality of studies was moderate to poor with short follow-up. The evidence supports the use of MEI because, overall, they do not decrease residual hearing, result in a functional gain in hearing comparable to CHA, and may improve perception of speech in noise and sound quality. We recommend the publication of long-term results comparing MEI with CHA, reporting a minimum of functional gain, speech perception in quiet and in noise, complications, and a validated PROM to guide the engineering of the new generation of MEI in the future.

Balance Function Disorders

NASA Technical Reports Server (NTRS)

1991-01-01

Researchers at the Balance Function Laboratory and Clinic at the Minneapolis (MN) Neuroscience Institute on the Abbot Northwestern Hospital Campus are using a rotational chair (technically a "sinusoidal harmonic acceleration system") originally developed by NASA to investigate vestibular (inner ear) function in weightlessness to diagnose and treat patients with balance function disorders. Manufactured by ICS Medical Corporation, Schaumberg, IL, the chair system turns a patient and monitors his or her responses to rotational stimulation.

Association Between Hearing Loss And Cauliflower Ear in Wrestlers, a Case Control Study Employing Hearing Tests.

PubMed

Noormohammadpour, Pardis; Rostami, Mohsen; Nourian, Ruhollah; Mansournia, Mohammad Ali; Sarough Farahani, Saeed; Farahbakhsh, Farzin; Kordi, Ramin

2015-06-01

According to anecdotal findings, some wrestling coaches and wrestlers believe that cauliflower ear might lead to hearing loss. Our preliminary study showed that the prevalence of hearing loss reported by the wrestlers with cauliflower ear is significantly higher than this rate among wrestlers without cauliflower ear. To the best of our knowledge, no other study has confirmed this finding employing hearing tests. To evaluate and to compare the prevalence of hearing loss among wrestlers with and without cauliflower ears employing hearing tests. The subjects were randomly selected form 14 wrestling clubs in Tehran. Subjects were 201 wrestlers with cauliflower ears (100 wrestlers with one cauliflower ear and 101 wrestlers with two cauliflower ears) and 139 wrestlers without cauliflower ears. All the participants in this study were interviewed to collect information on demographic factors and medical history of risk factors and diseases related to hearing loss. The subjects in both groups underwent otoscopic and audiologic examinations. Audiometric examination results at the frequency range of 0.5 - 8 KHz showed that the prevalence of hearing loss among cauliflower ears was higher than this rate among non-cauliflower ears. Also, the percentage of positive history of ear infections among cauliflower ears (8.4%) was about two times more than this finding among non-cauliflower ears (4.9%). This difference tended to be significant (OR: 1.86, P = 0.06, 95% CI: 0.98 - 3.53). To the best of our knowledge, this is the first study showing that the prevalence of hearing loss among cauliflower ears is higher than this rate among non-cauliflower ears confirmed by audiological tests. This emphasizes that, more preventive measures such as mandatory ear gear for wrestlers are required.