To see the other types of publications on this topic, follow the link: Ear, Middle.
Dissertations / Theses on the topic 'Ear, Middle'
Create a spot-on reference in APA, MLA, Chicago, Harvard, and other styles
Consult the top 50 dissertations / theses for your research on the topic 'Ear, Middle.'
Next to every source in the list of references, there is an 'Add to bibliography' button. Press on it, and we will generate automatically the bibliographic reference to the chosen work in the citation style you need: APA, MLA, Harvard, Chicago, Vancouver, etc.
You can also download the full text of the academic publication as pdf and read online its abstract whenever available in the metadata.
Browse dissertations / theses on a wide variety of disciplines and organise your bibliography correctly.
1
Albiin, Nils. "Middle ear structure in relation to function : the rat in middle ear research." Doctoral thesis, Umeå universitet, Anatomi, 1985. http://urn.kb.se/resolve?urn=urn:nbn:se:umu:diva-141294.
Full textAbstract:
The present study was undertaken to evaluate the rat as a model for middle ear research. The rat was chosen primarily because the gross structure of its middle ear shows several similarities to that of man. It was considered of great importance to make a thorough structural study of the rat middle ear and to compare the results with those reported for the human middle ear. The thesis therefore includes independent studies on various aspects of rat middle ear structure and function as well as a review of the literature. The most pertinent findings in the experimental part of this study were the following. The rat Eustachian tube consists of a nasopharyngeal, and a cartilaginous and bony portion. The orifice of the nasopharyngeal portion is composed of two soft tissue lips, which appear to be opened mainly by the action of the salpingopharyngeal muscle, but also by the levator and tensor veli palatini muscles. The cartilaginous portion appears to be opened solely by the tensor veli palatini muscle. The tensor tympani muscle seems to have no effect on the tube. A ciliated and secretory epithelium lines the inferomedial walls of the tube throughout its length. In the tympanic cavity these thelial cell types extend as two tracts - one anterior and the other inferoposterior to the promontory - which communicate with the epitympanic/attic compartments. The remaining parts of the tube and the tympanic cavity are covered by a squamous/cuboidal, non-ciliated epithelium. The subepithelial loose connective tissue contains vessels, nerves, and connective tissue cells, among these mast cells. The mast cells are confined to areas covered by the ciliated epithelium, and in the floor of the bulla, in the pars flaccida, and along the manubrial vessels. Glands are restricted to the Eustachian tube. In the clearance/transport of serum-like material, from the epitympanum towards the tube, hydrostatic forces appear to be important. The tympanic membrane is vascularized from meatal and tympanal vessels. Meatal vessels branch in the pars flaccida and along the handle of the malleus, where they are localized directly beneath the outer, keratinizing, stratified, squamous epithelium. Furthermore, meatal vessels form a vascular network at the junction between the fibrocartilaginous annulus and the tympanic sulcus. Tympanal vessels send branches to the periphery of the pars tensa, where they run immediately beneath the tympanal, simple, squamous epithelium. In the major portion of the pars tensa, no blood vessels were found. The rat stapedial artery is a thin-walled vessel with a wide lumen. Without branching, it runs through the tympanic cavity to the extratympanal regions it supplies. In contrast to the corresponding artery in man, the rat stapedial artery persists throughout life. The artery does not seem to be affected by the fluid produced during experimentally induced otitis media with effusion. The middle ear structure in the rat and in man show both similarities and differences. If the differences are kept in mind and considered, it would seem that the rat is indeed a suitable model for experimental middle ear research.<br>digitalisering@umu
2
Gariepy, Brian. "Finite-element modelling of the newborn ear canal and middle ear." Thesis, McGill University, 2011. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=97023.
Full textAbstract:
Hearing loss is a very common birth defect. However, current hearing screening does not provide adequate specificity. Tympanometry is a potential hearing-screening tool that is specific to conductive hearing loss, but the tympanograms of newborns are currently not standardized and not well understood. Finite-element models of the newborn ear canal and middle ear are developed and their responses to the tympanometric probe tone are studied. Low-frequency and dynamic simulations are used to model the ear's response to sound frequencies up to 2000 Hz. Material properties are taken from previous measurements and estimates, and the sensitivities of the models to these different parameters are examined. The simulation results are validated through comparison with previous experimental measures. Finally, the relative admittances of the ear canal and the middle ear at different frequencies are examined and implications for the interpretation of newborn tympanometry are discussed.<br>La perte d'audition est une anomalie congénitale très courante. Toutefois, le dépistage auditif actuel n'est pas spécifique. La tympanométrie est un dépistage auditif potentiel qui aide à dépister la surdité de transmission, mais les tympanogrammes des nouveau-nés ne sont pas bien compris ou standardisés. Deux modèles d'éléments finis ont été développés: l'un pour le conduit auditif des nouveau-nés, et l'autre pour l'oreille moyenne. Leurs réponses au ton de sonde tympanométrique sont étudiées. Les simulations quasi-statiques et dynamiques sont utilisés pour modeler la réponse de l'oreille aux fréquences de son jusqu'à 2000 Hz. Les propriétés matérielles sont prises des mesures et des estimations précédentes, et les sensibilités des modèles à ces différents paramètres sont examinées. Les résultats des simulations sont validés par la comparaison avec les mesures expérimentales précédentes. Enfin, les impédances relatives du canal externe de l'oreille et de l'oreille moyenne aux fréquences différentes sont examinées et les implications pour l'interprétation de la tympanométrie du nouveau-né sont discutées.
3
Joshi, Leena. "Middle ear development : genetics and disease." Thesis, King's College London (University of London), 2013. http://kclpure.kcl.ac.uk/portal/en/theses/middle-ear-development(1c50ca89-84f5-4011-a9a7-1707ec43ded1).html.
Full textAbstract:
The mammalian middle ear is composed of three bony ossicles, the malleus, incus, and stapes that function to conduct sound from the external to the inner ear. Normal development of middle ear structures is integral for transduction of sound, defects resulting in conductive deafness. Mice are reliant on both embryonic and postnatal developmental events to acquire hearing, and Eya1 mutant mice present with middle ear defects during both these developmental periods. Therefore, the aim of this project was to investigate the role of Eya1 in middle ear development and disease. Eya1 mutant mice on several backgrounds have previously been characterised with middle ear ossicle defects, however the role of Eya1 in regulating ossicle development has not been investigated. In this project, I characterise novel ossicle joint patterning defects of Eya1 mice of the C57BL/6 background, and show Eya1 to be expressed in the middle ear ossicles during embryonic development. I also investigate genetic regulators of joint development and show Gdf5 misexpression in the Eya1 +/- middle ear. I suggest Eya1 indirectly regulates middle ear joint patterning through a more general role in cartilage development. During postnatal development, Eya1 may further be required for the maintenance of joints. Transformation of Meckel’s cartilage results in separation of the jaw and middle ear, and is a characteristic feature of modern mammaliaforms. The Eya1 +/- mouse exhibits a delay in postnatal Meckel’s cartilage development, suggesting Eya1 as a regulator of this process. I investigate mechanisms associated with transformation of Meckel’s cartilage, and suggest Eya1 regulates this process indirectly through recruitment of TRAP positive cells. During adult stages of postnatal development, Eya1 +/- mice are predisposed to developing middle ear infections. With the use of microscopy and histological techniques, I characterise the Eya1 +/- mouse as a model of otitis media.
4
Jung, David S. "Optical assessment of middle ear inflammation." Thesis, University of Nottingham, 2016. http://eprints.nottingham.ac.uk/38529/.
Full textAbstract:
This thesis describes the development of an optical device to assess the inflammatory state of the middle ear mucosa through the ear canal, after ventilation tube insertion in otitis media with effusion in children. An optical phantom of the middle ear was developed in order to allow repeatable experiments. The phantom consists of eardrum and mucosa while all other structures are neglected. The optical properties of the phantom were determined based on literature review and experiments on an animal model. The middle ear mucosa phantom is based on a polyester resin, with dyes added to introduce absorption and a titanium dioxide based white colour to introduce scattering. Four phantom are created to model healthy, intermediate, and diseased mucosa. Several approaches are taken for the eardrum phantom, either a grid glass diffuser or a resin phantom with scattering introduced by fibre glass is used. Middle ear inflammation affects the mucosa while the eardrum might not be affected. Hence, the mucosa must be assessed and signals resulting from the eardrum, blocking the direct light path, filtered, in order to reduce background signals. During literature research and preliminary experiments, multi-wavelength measurements were selected to assess the mucosa and confocal techniques to allow measurements through the eardrum. The tissue is illuminated with two wavelengths and the reflected signal analysed. Appropriate selection of the wavelengths at characteristic point of the absorption spectrum of blood allows assessment of the inflammation via the blood concentration in tissue. The confocal idea was adopted leading to the “anti-confocal” system, where a central stop replacing the pinhole rejects light from the plane in focus rather than rejecting all out of focus light. With the eardrum in focus and a stop radius larger than the confocal pinhole radius (r_stop=0.48mm), most light from the eardrum is rejected (reduced to 0.2%) while signal from the mucosa are still detected (reduced to 25.6%), according to simulations. Simulations of the anti-confocal system showed an increase of the signal level by a factor of 3.2 or a 1.5 times higher background rejection ratio (SBR) compared to the conventional confocal system, when keeping the respective other value constant. This advantage still holds and is even improved in some cases when increasing the scattering coefficient (from 11 up to 44mm-1), reducing the scattering anisotropy (from 0.99 to 0.6), changing the distance between eardrum and mucosa (0.5 to 8mm), inaccurate focus (up to 3mm out of focus), and changed NA (0.055-0.27). Further, best wavelengths for measurements of the blood concentration and thus inflammation of the mucosa have been determined in simulations to be 730 and 546nm. In the investigated range of wavelengths (500 to 940nm), the relation of near infra-red signal at 730nm to green reflection signal at 546nm gives the highest response to a change in the total blood level in tissue while showing a low response to changes in blood oxygenation. The anti-confocal system was built as bench-top system and characterised. Instead of using a physical stop, a CCD camera was used and anti-confocal filtering done during post-processing, by selecting certain pixel on the camera. Experimental results confirmed the simulations and showed an increased signal and easier use of the anti-confocal system compared to the confocal system as no exact focus is required. An anti-confocal stop with 0.48mm radius showed best performance, showing a high contrast and low variation during the measurement. Measurements were possible with increased scattering (simulated by the stronger scattering grid glass diffuser) and attenuation (simulated by absorbing dyes added to the resin eardrum phantom) of the eardrum, increased distance between eardrum and mucosa (2-6mm), defocus of the system, and altered orientation of the phantom surface (0-10deg) with differences in the mucosal blood level still detectable. But the measured inflammation index is influenced by the transmission properties of the eardrum. While the influence of absorption can be accounted for by confocal detection of the properties of the eardrum during the same measurement, improved signal processing and modelling of light propagation are necessary to account for changed scattering of the eardrum. Tests on the hand of healthy volunteers showed that the proposed system is able to detect a change in the concentration of haemoglobin of living tissue measured through an eardrum simulating scattering layer. The next steps are the improvement of signal processing to account for changes of the measured inflammation index due to scattering of the eardrum. Once this is achieved, the optical system can be minimised to allow measurements on the ear and pilot trials for evaluation and calibration of the system.
5
Qi, Li. "Non-linear finite-element modelling of newborn ear canal and middle ear." Thesis, McGill University, 2008. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=21904.
Full textAbstract:
Early hearing screening and diagnosis in newborns are important in order to avoid problems with language acquisition and psychosocial development. Current newborn hearing screening tests cannot effectively distinguish conductive hearing loss from sensorineural hearing loss, which requires different medical approaches. Tympanometry is a fast and accurate hearing test routinely used for the examination of conductive hearing loss for older children and adults; however, the tympanograms are hard to interpret for newborns and infants younger than seven months old due to significant differences in the outer and middle ear. In this work, we used the finite-element method (FEM) to investigate the behaviour of the newborn canal wall and middle ear in response to high static pressures as used in tympanometry. The model results are compared with the analysis results of multi-frequency tympanometry measured in healthy newborns and with available tympanometry measurements in newborns with presumed middle-ear effusion. Analysis results of multi-frequency tympanometry show that both susceptance and conductance increase with frequency. The equivalent volumes calculated from both tails of both the admittance and susceptance functions decreased as frequency increases. The volumes derived from susceptance decrease faster than do those derived from admittance. The 5th-to-95th percentile ranges of equivalent volume and energy reflectances are much lower than previous measurements in older children and adults. Non-linear finite-element models of the newborn ear canal and middle ear were developed. The ear-canal model indicates that the Young's modulus of the canal wall has a significant effect on the ear-canal volume change, which ranges from approximately 27% to 75% over the static-pressure range of ±3 kPa. The middle-ear model indicates that the middle-ear cavity and the Young's modulus of the tympanic membrane (TM) have significant effects on TM volume displacements. The TM volum<br>Il est important d'effectuer un dépistage et un diagnostic précoce de l'audition du nouveau-né afin d'éviter qu'il éprouve plus tard des difficultés dans l'acquisition du langage et dans son développement psychosocial. Les épreuves actuelles de dépistage de l'audition des nouveau-nés ne permettent pas de distinguer efficacement entre une perte auditive due à une surdité de transmission et une perte sensorineurale, chacun de ces troubles exigeant un traitement médical différent. La tympanométrie est une épreuve rapide et exacte que l'on utilise habituellement pour déceler une perte auditive due à une surdité de transmission chez les enfants plus âgés et chez les adultes. Cependant, dans le cas des nouveau-nés et des enfants en bas âge, les tympanogrammes sont difficiles à interpréter en raison de différences importantes dans l'oreille moyenne et externe. Dans cette étude, nous avons utilisé l'analyse par éléments finis pour examiner les comportements que manifestent la paroi du conduit auditif et l'oreille moyenne des nouveau-nés en réaction aux pressions statiques élevées utilisées en tympanométrie. Les résultats du modèle sont ensuite comparés aux résultats d'analyses de tympanométrie multifréquence effectuées sur des nouveau-nés en santé, et aux mesures tympanométriques disponibles réalisées sur des nouveau-nés souffrant d'un épanchement présumé dans l'oreille moyenne. Les résultats d'analyses de tympanométrie multifréquence indiquent que tant la susceptance que la conductance augmentent avec la fréquence. Les volumes équivalents calculés à partir de deux extrémités des fonctions d'admittance et de susceptance décroissent à mesure que la fréquence augmente. Les volumes issus de la susceptance diminuent plus rapidement que ceux issus de l'admittance. Les réflectances d'énergie et les volumes équivalents comprises dans une plage allant du 5e au 95e percentile sont beaucoup moins élevées que les$
6
UEDA, HIROMI, and MASAYO BAKU. "A RARE CASE OF MIDDLE EAR ADENOMA." Nagoya University School of Medicine, 2014. http://hdl.handle.net/2237/20555.
Full text
7
Tuck-Lee, James Peter. "Finite element analysis of middle ear mechanics /." May be available electronically:, 2007. http://proquest.umi.com/login?COPT=REJTPTU1MTUmSU5UPTAmVkVSPTI=&clientId=12498.
Full text
8
Ozyurt, Deniz. "Effects Of Scuba Diving On Middle Ear Pressure." Master's thesis, METU, 2006. http://etd.lib.metu.edu.tr/upload/12607207/index.pdf.
Full textAbstract:
ABSTRACT
EFFECTS OF SCUBA DIVING ON MIDDLE EAR PRESSURE
Ö<br>zyurt, Deniz
MS. Department of Physical Education and Sports
Supervisor : Prof. Dr. Feza Korkusuz
Co-Supervisor: Dr. Mehmet Ö<br>zekmekç<br>i
April 2006, 42 pages
Since<br>the self-contained underwater breathing apparatus (scuba) was developed<br>the growth in the recreational diving population leaded an increase in diving-related injuries, mostly about the ear barotraumas. Previous findings show that inexperienced divers are more predisposed to ear barotraumas. This study was performed to see the dive related alterations of the middle ear pressure and the compliance of the tympanic membrane due to experience (experienced - skin divers and/or underwater rugby players and inexperienced -not use to skin diving or such water sports) and depth (3m and 12m) in 22 novice divers with normal pre-dive audiometry, tympanometry, and otorhinolaryngologic examination. Pre dive otologic inspections were taken and pre dive / post dive tympanograms were measured for each depth. In 8 ears of the 5 inexperienced divers either hyperemia or hemotympany were observed in the second day&<br>#8217<br>s (12m) otoscopic inspections. In the first post dive tympanometric measurements<br>middle ear pressure changes were observed in 19 ears of 14 divers. The compliance was not changed in 5 ears of 3 divers and increased in the reminder. In the second tympanometric measurements, 12 ears of the 8 divers showed negative middle ear pressure and compliance was not changed in 10 ears of 5 divers and increased in the reminder. Due to experience and middle ear pressure changes of each day<br>no meaningful, statistically significant correlation was found. Also no meaningful correlations were found neither for experience and compliance. A correlation of .542 between experience status and otologic inspection prior to 12m depth dives was a contradiction to the hypothesis there would not be any significant difference between experienced and well trained inexperienced groups as the otologic variations such as hyperemia or hemotympany were only seen in inexperienced novices. Again<br>the correlation of .571 showed that 3m depth dives had grater frequency of middle ear pressure changes than 12m depth dives. Similarly<br>due to the compliance correlation of .516, 3m depth dives had a grater frequency of compliance increases than 12m depth dives. These results however should be reconsidered as the 3m depth was the first open water dive day and 12m depth was the next day which the novices could use to the open water conditions.
9
Elkhouri, Nidal. "Finite-element modelling of the gerbil middle ear." Thesis, McGill University, 2005. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=98957.
Full textAbstract:
Hearing loss is the third leading chronic disability after arthritis and hypertension, and the most frequent birth defect. Non-invasive diagnoses and middle-ear prostheses are often unsatisfactory, partly because of a lack of understanding of middle-ear mechanics. The focus of this thesis is to develop a 3-D finite-element model to quantify the mechanics of the gerbil middle ear. An MRM dataset with a voxel size of 45 &mgr;m, and an x-ray micro-CT dataset with a voxel size of 5 um, supplemented by histological images, are the basis for 3-D reconstruction and finite-element mesh generation. The eardrum model is based on moire shape measurements. The material properties of all the structures in the model are based on a priori estimates from the literature.<br>The behaviour of the finite-element model in response to a static pressure of 1 Pa is analyzed. Overall, the model demonstrates good agreement with low-frequency experimental data. For example, (1) the ossicular ratio is found to be about 3.5; (2) maximum footplate displacements are about 34.2 run +/- 0.04 nm; (3) the motion of the stapes is predominantly piston-like; (4) the displacement pattern of the eardrum shows two points of maximum displacements, one in the posterior region and one in the anterior region. The results also include a series of sensitivity tests to evaluate the significance of the different parameters in the finite-element model. Finally, in an attempt to understand how the overall middle-ear mechanics is influenced by the anterior mallear ligament and the posterior incudal ligament, results are shown for cutting or stiffening the ligaments.
10
Mikhael, Chadia. "Finite-element modelling of the human middle ear." Thesis, McGill University, 2005. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=82619.
Full textAbstract:
Most models of the middle ear are based on oversimplified geometries and iterative material-property fitting to experimental data which may yield physiologically incorrect estimates.<br>The aim of our work was to build an accurate human middle-ear finite-element model that is based on accurate geometry and a priori material-property estimates.<br>A human temporal-bone specimen was obtained for which the middle-ear response had been measured by means of laser Doppler vibrometry. High-resolution micro-computed tomography data for the specimen were used for accurately defining structure geometry. This model comprises the tympanic membrane, the ossicles, two joints, and four ligaments. We assigned estimated material-property values derived from the literature.<br>We compared the response of our model with those of other human middle-ear models, and with experimental measurements including those from the same ear. Sensitivity of the model to several of its parameters was also investigated.
11
Bornitz, Matthias, Thomas Zahnert, Hans-Jürgen Hardtke, and Karl-Bernd Hüttenbrink. "Identification of Parameters for the Middle Ear Model." Saechsische Landesbibliothek- Staats- und Universitaetsbibliothek Dresden, 2014. http://nbn-resolving.de/urn:nbn:de:bsz:14-qucosa-135790.
Full textAbstract:
This paper presents a method of parameter identification for a finite-element model of the human middle ear. The parameter values are estimated using a characterization of the difference in natural frequencies and mode shapes of the tympanic membrane between the model and the specimens. Experimental results were obtained from temporal bone specimens under sound excitation (300–3,000 Hz). The first 3 modes of the tympanic membrane could be observed with a laser scanning vibrometer and were used to estimate the stiffness parameters for the orthotropic finite-element model of the eardrum. A further point of discussion is the parameter sensitivity and its implication for the identification process<br>Dieser Beitrag ist mit Zustimmung des Rechteinhabers aufgrund einer (DFG-geförderten) Allianz- bzw. Nationallizenz frei zugänglich
12
Bornitz, Matthias, Thomas Zahnert, Hans-Jürgen Hardtke, and Karl-Bernd Hüttenbrink. "Identification of Parameters for the Middle Ear Model." Karger, 1999. https://tud.qucosa.de/id/qucosa%3A27677.
Full textAbstract:
This paper presents a method of parameter identification for a finite-element model of the human middle ear. The parameter values are estimated using a characterization of the difference in natural frequencies and mode shapes of the tympanic membrane between the model and the specimens. Experimental results were obtained from temporal bone specimens under sound excitation (300–3,000 Hz). The first 3 modes of the tympanic membrane could be observed with a laser scanning vibrometer and were used to estimate the stiffness parameters for the orthotropic finite-element model of the eardrum. A further point of discussion is the parameter sensitivity and its implication for the identification process.<br>Dieser Beitrag ist mit Zustimmung des Rechteinhabers aufgrund einer (DFG-geförderten) Allianz- bzw. Nationallizenz frei zugänglich.
13
Kim, Young Seon. "Transfer function of the embryonic avian middle ear /." free to MU campus, to others for purchase, 2002. http://wwwlib.umi.com/cr/mo/fullcit?p3074415.
Full text
14
Sato, Shigenori, Hisashi Yokoi, Shigeji Fukuta, Makoto Kozuka, and Noriyuki Yanagita. "Morphological Studies on Middle Ear Barotrauma in Guinea Pigs." 名古屋大学医学部, 1997. http://hdl.handle.net/2237/6186.
Full text
15
Wright, Thomas. "The linear and nonlinear biomechanics of the middle ear." Doctoral thesis, Stockholm, 2005. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-258.
Full text
16
Roberts, Caroline Marie. "The impact of rheumatoid arthritis on middle ear function." College Park, Md. : University of Maryland, 2007. http://hdl.handle.net/1903/7327.
Full textAbstract:
Thesis (Au. D.) -- University of Maryland, College Park, 2007.<br>Thesis research directed by: Hearing and Speech Sciences. Title from t.p. of PDF. Includes bibliographical references. Published by UMI Dissertation Services, Ann Arbor, Mich. Also available in paper.
17
G, Akache Fadi. "An experimental study of middle-ear vibration in rats /." Thesis, McGill University, 2005. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=82461.
Full textAbstract:
Animal models are valuable tools in auditory research. Rats are potentially very useful for this purpose. They are low in cost, they are genetically similar to humans, and the middle-ear structures are easily approachable. The goal of the present study is to better characterize the mechanics of the rat middle ear by measuring frequency responses at multiple points on the tympanic membrane for the first time, and with better frequency resolution than in previous studies. A laser Doppler vibrometer was used to measure the vibrations. Measurements were done on seven rats. Tympanic membrane vibrations at seven different points, in the frequency range of 1 000 to 10 000 Hz, are presented. We provide a measure of the noise floor and investigate the linearity of the rat tympanic membrane. The repeatability of the rat's middle-ear response and inter-animal variability at the umbo are presented. The vibration modes of the tympanic membrane and manubrium are also investigated.
18
Nambiar, Shruti. "An experimental study of middle-ear vibrations in gerbils." Thesis, McGill University, 2010. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=86940.
Full textAbstract:
The Mongolian gerbil has been widely used in middle-ear research, as it is low in cost and has easily approachable middle-ear structures. The goal of this study was to present vibration measurements of the gerbil tympanic membrane. A single-point laser Doppler vibrometer was used to measure displacement frequency responses in twelve gerbils at multiple points on the tympanic membrane. A sinusoidal sweep excitation was used to perform the vibration measurements. Displacements at the umbo, normalized with respect to the sound pressure level measured near the tympanic membrane, are presented over the frequency range from 0.2 to 10 kHz, and compared with measurements published in the literature. Displacements at multiple locations on the pars flaccida and pars tensa are also presented, and the variability and repeatability of the measurements are investigated.<br>La gerbille de Mongolie est de plus en plus utilisée dans la recherche sur l'oreille moyenne, car elle est peu coûteuse, et les structures de son oreille moyenne sont facilement accessibles. Le but de cette étude est de présenter des mesures de vibrations du tympan de la gerbille. Des réponses fréquentielles des déplacements furent acquises à l'aide d'un vibromètre à laser Doppler Polytec, dans douze gerbilles à plusieurs points sur le tympan. Un stimulus à balayage sinusoïdal fut employé. Des déplacements à l'umbo, normalisés par le niveau de pression acoustique mesuré près du tympan, sont présentés dans la gamme de fréquence de 0.2 à 10 kHz, et comparés aux mesures publiées dans la littérature. Des déplacements à plusieurs endroits sur le pars flaccida et le pars tensa sont aussi présentés, et la variabilité et la répétabilité des mesures sont étudiées.
19
Hatamzadeh-Tabrizi, Joubin. "Using active contours for segmentation of middle-ear images." Thesis, McGill University, 2003. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=79231.
Full textAbstract:
Image segmentation, or the extraction of the boundaries of objects, is one of the most important problems in computer vision and image processing. As a high-level technique for boundary identification, active contours are used extensively for segmentation purposes.<br>Two different active contour approaches, i.e., parametric active contours and discrete dynamic contours, were used and compared for the segmentation of middle-ear images. We used histological and Magnetic Resonance Microscopy (MRM) image datasets for our experiments.<br>Parametric and discrete dynamic contours show similar boundary identification results for the histological and MRM datasets. Gradient, Gradient Vector Flow (GVF), and the gradient plus pressure were used as the external force. The gradient has the disadvantage of having a restricted capture range. Two solutions for improving the capture range, gradient vector flow and pressure force, were compared. Although GVF provides a good capture range, it sometimes wrongly identifies the low-contrast boundaries. It was also found that GVF may wrongly identify the boundaries of close neighbouring structures. As an alternative, pressure forces have shown promising results for histological and MRM middle-ear images. For the same initial contours, a larger number of iterations is required for the parametric contours to converge to the boundary than with the discrete dynamic contours, when the gradient is used as the external force. However, when using GVF and gradient plus pressure, parametric active contours require a smaller number of iterations for active contour convergence, compared with the discrete dynamic approach.<br>The use of open contours was demonstrated for shared boundaries and thin structures, in addition to the usual closed contours.
20
Ladak, Hanif M. "Finite-element modelling of middle-ear prostheses in cat." Thesis, McGill University, 1994. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=68035.
Full textAbstract:
Discontinuity of the middle-ear ossicular chain results in conductive hearing loss. Two prostheses commonly used to surgically repair the ossicular chain are the MSA and the MFA. In the MSA, a strut is connected between the malleus and the head of the stapes, while in the MFA a strut is connected between the malleus and the footplate of the stapes. In this work, finite-element models of the MSA, MFA and normal cat middle ear are developed. The models are valid for low frequencies (below 300 Hz) and for physiological sound levels. The mechanical behaviour of the normal middle-ear model is compared with that of the MFA and MSA models. Several parameters are then varied in order to study their relative importance in the models. The effects of strut placement on the behaviour of the MSA and MFA models are also investigated.
21
Ellaham, Nicolas. "An experimental study of middle-ear vibrations in gerbils." Thesis, McGill University, 2008. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=18655.
Full textAbstract:
The Mongolian gerbil has become increasingly popular in middle-ear research, as it is low in cost and has easily approachable middle-ear structures. The goal of this thesis is to present vibration measurements on the gerbil eardrum. Displacement frequency responses are acquired in five gerbils at three or four points along the manubrium and at up to 8 points on the eardrum. We use a Polytec laser Doppler vibrometer to perform measurements with a sinusoidal-sweep stimulus. Displacements, normalized with respect to the sound pressure level measured near the eardrum, are presented over the frequency range from 0.15 to 10 kHz, and compared with measurements published in the literature. Spatial displacement patterns along the manubrium and on the tympanic membrane are presented. The variability and repeatability of the measurements are investigated with an emphasis on temporal effects due to the drying and rehydration of middle-ear structures.<br>Le gerbil mongolien est devenu de plus en plus populaire dans la recherche sur l'oreille moyenne, car il n'est pas trop couteux, et les structures de l'oreille moyenne sont facillement accessibles. Le but de cette thèse est de présenter des mesures de vibration de tympan du gerbil. Des réponses fréquentielles des déplacements sont acquises dans cinq gerbils à trois ou quatre points le long du manubrium, et à autant que 8 points sur le tympan. Nous employons un vibromètre à laser Doppler de Polytec pour effectuer des mesures avec un stimulus à balayage sinusoïdal. Des déplacements, normalisés par le niveau de pression acoustique mesuré près du tympan, sont présentés sur la gamme de fréquence de 0.15 à 10 kilohertz, et comparés aux mesures publiées dans la littérature. Des motifs spatiaux de déplacement le long du manubrium et sur la membrane tympanique sont présentés. La variabilité et la répétabilité des mesures sont étudiées avec une emphase sur les effets temporels dus à la déshydratation et à la ré-humidification des structures de l'oreille moyenne.
22
O'Connor, Kevin N. (Kevin Neill) 1977. "Analysis of exotic cat vocalizations and middle-ear properties." Thesis, Massachusetts Institute of Technology, 2001. http://hdl.handle.net/1721.1/86822.
Full textAbstract:
Thesis (M.Eng.)--Massachusetts Institute of Technology, Dept. of Electrical Engineering and Computer Science, 2001.<br>Includes bibliographical references (p. 231-232).<br>by Kevin N. O'Connor.<br>M.Eng.
23
Hussain, Raabid. "Augmented reality based middle and inner ear surgical procedures." Thesis, Bourgogne Franche-Comté, 2020. http://www.theses.fr/2020UBFCI014.
Full textAbstract:
Les procédures otologiques impliquent la manipulation de petites structures délicates et complexes de l'anatomie de l'os temporal qui se trouvent à proximité de nerfs et de vaisseaux sanguins critiques. La réalité augmentée (RA) peut grandement être benéfique au domaine otologique en fournissant des informations supplémentaires anatomiques et de navigation fusionnée sur un seul écran. Cependant, bien que la navigation conventionnelle ait prouvé son utilité en otologie, le développement de la RA dans ce domaine reste limitée. Ce projet vise à développer des solutions RA pour les interventions chirurgicales de l'oreille moyenne et interne.Nous proposons deux applications de la RA à cet égard. Dans la première application, des informations sur les structures de l'oreille moyenne sont obtenues à partir d'un examen tomodensitométrique préopératoire et sont superposées à la vidéo chirurgicale de la membrane tympanique. Cela permet au chirurgien d'avoir des informations en temps réel sur les structures anatomiques cibles et l'instrument chirurgical localisés derrière la membrane tympanique sans élévation du volet tympanoméatal. En prolongement de ce système, nous proposons également de visualiser le modiolus cochléaire sur la vidéo chirurgicale de l'oreille moyenne et interne permettant l'implantation transmodiolaire de l'implant cochléaire à travers le conduit auditif externe.Les deux systèmes de RA proposés sont conçus de manière mini-invasive et sont uniquement basés sur des algorithmes de vision, éliminant la nécessité de systèmes traditionnels de suivi magnétique et/ou optique que l'installation dans l'environnement du bloc opératoire est facile. Ce travail ouvre des perspectives importantes sur les procédures otologiques mini-invasives grâce à des solutions basées sur la RA<br>Otologic procedures involve manipulation of small, delicate and complex structures in the temporal bone anatomy which are in close proxmity of critical nerves and blood vessels. Augmented reality (AR) can highly benefit the otological domain by providing supplementary anatomical and navigational information unified on a single display. However, despite being composed of mainly rigid bony structures, the awareness and acceptance of possibilities of AR systems in otology is fairly low. This project aims at developing video-based AR solutions for middle and inner ear surgical procedures.We propose two applications of AR in this regard. In the first application, information about middle ear cleft structures is obtained from a preoperative CT-scan exam and overlayed onto the surgical video of the tympanic membrane. This system provides the surgeon with real-time information about the anatomical target structures and the surgical instrument behind the tympanic membrane without tympanomeatal flap elevation. As an extension of this system, we also propose to visualize the cochlear modiolus in the real-time surgical video of the middle and inner ear cleft enabling transmodiolar implantation of the cochlear implant through the external auditory canal.Both proposed AR systems are designed in a minimally invasive manner and are solely based on vision algorithms eliminating the need for traditional magnetic and optical tracking systems. The first trials showed an easy installation in the operating room environment. This work opens important perspectives into minimally invasive otologic procedures through AR-based solutions
24
Berling, Holm Katarina. "The Chorda Tympani Nerve : Role in Taste Impairment in Middle Ear Disease and after Ear Surgery." Doctoral thesis, Uppsala universitet, Centrum för klinisk forskning, Västerås, 2017. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-316591.
Full textAbstract:
The chorda tympani nerve, also known as the taste nerve, runs uncovered through the middle ear cavity, a localization that exposes the nerve to pathological processes and surgical trauma in the middle ear. People operated on for otosclerosis tend to complain more about postoperative taste disturbances than those operated on for chronic otitis media. It has been suggested that this difference may be explained by gradual deterioration of chorda tympani nerve function caused by chronic otitis media infection and that further impairment caused by surgery is less noticeable in these patients. This thesis aimed to evaluate the function of the chorda tympani nerve, the effects of middle ear disease on taste and complications resulting from ear surgery for chronic otitis media or otosclerosis. This information will help to improve the ear surgeon’s ability to predict the prognosis of iatrogenic taste disturbances in patients with middle ear disease and after ear surgery. Taste was assessed using electrogustometry and the filter paper disc method before and after surgery for chronic otitis media or otosclerosis. Patients also completed questionnaires about symptoms and quality of life. The status of the chorda tympani nerve upon surgical opening of the ear and grading of the trauma to the nerve during the surgery were recorded. The ultrastructure of the chorda tympani nerve from healthy ears and from ears with chronic otitis media was examined. Electrogustometry and the filter paper disc method were evaluated. The results of electrogustometry and the filter paper disc method were highly reproducible, although their correlation was moderate. Patients with chronic otitis media, patients with a more traumatized nerve, female patients and younger patients were more likely to report postoperative taste disturbances. Most of the patients recovered their taste after 1 year. The quality of life study showed only minor changes after surgery. Electron microscopic observations of nerves from ears with chronic otitis media showed signs of structural degeneration, although signs of regeneration, such as sprouting were also observed. This results may explain the recovery of taste postoperatively and indicate that the nerve should be carefully handled during surgery.
25
Edfeldt, Lennart. "Middle Ear Cholesteatoma : Surgical Treatment, Follow-up and Hearing Restoration." Doctoral thesis, Uppsala universitet, Öron-, näs- och halssjukdomar, 2013. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-198121.
Full textAbstract:
Although middle-ear cholesteatoma is a major topic in otological research, its etiology and pathogenesis remain unclear. Pediatric cholesteatoma is considered more aggressive than adult cholesteatoma, as it has a higher rate of growth, is more often infected and exhibits wider extension. Higher incidence of residual and recurrent disease after surgical treatment of pediatric cholesteatoma has been observed in most studies. In this study, the results are presented from a canal wall down (CWD) obliteration technique used in 330 adult patients (Paper I) with cholesteatoma, evaluated at 1, 3 and 6 years following surgery. Additionally, results are offered from 57 pediatric patients (Paper II) using identical surgical technique and compared with adults. The surgical and hearing outcomes in both groups showed a low incidence of residual and recurrent disease and a high rate of ear water resistance without infection. The results were unrelated to the severity and extension of disease, as well as to age and previous surgery. No differences were found in outcomes between adult and pediatric cholesteatoma patients. The thesis also describes the use of diffusion-weighted magnetic resonance imaging (DW-MRI) (Paper III) in follow-up examinations of adult cholesteatoma patients undergoing surgical treatment. Non-echo planar diffusion-weighted imaging (Non-EPI DW-MRI)increased the accuracy of clinical examinations. It is concluded that the use of non-EPI DW-MRI should be mandatory in clinical follow-ups after cholesteatoma surgery. In Paper IV a relatively new mode of hearing rehabilitation was investigated, with an active middle ear implant (AMEI), in patients with chronically disabled ears. Functional hearing results were compared with the previous use of conventional hearing aids before and after AMEI implantation. Moreover, the consequences of positioning of the implant in the middle ear were evaluated using cone beam computed tomography (CBCT), a modification of conventional computed tomography. The hearing results, assessed with AMEI, were found to be less dependent on the precise positioning of the floating mass transducer(FMT) against the round window membrane (RWM) than was anticipated. Further, the hearing results were noted to be comparable with those with conventional hearing aids and even superior at high frequencies.
26
Daniel, Sam J. "Finite-element model of the human eardrum and middle ear." Thesis, McGill University, 2002. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=29429.
Full textAbstract:
Computer-generated models are increasingly being used in otolaryngology for teaching purposes, pre-operative planning and clinical simulations, especially when dealing with small complex areas such as the middle ear.<br>One technique used to analyse the mechanics of complex models is the finite-element method whereby the system of interest is divided into a large number of small simple elements. The mechanical properties and applied forces are represented by functions defined over each element, and the mechanical response of the whole system can then be computed.<br>A unique three-dimensional finite-element model of the human eardrum and middle ear was devised. This model takes advantage of phase-shift moire shape measurements to precisely define the shape of the eardrum. The middle-ear geometry is derived from histological serial sections and from high-resolution magnetic-resonance microscopy of the human ear.<br>The model allows an improved understanding of the mechanics of the human middle ear, can simulate various pathological conditions, and assist in the design of ossicular prostheses.
27
Funnell, Susan M. "An approach to finite-element modelling of the middle ear /." Thesis, McGill University, 1989. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=62001.
Full text
28
Gunton, M. de la R. "Functional aspects of vocalisation and middle ear morphology of shrews." Thesis, University of Cambridge, 1985. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.377845.
Full text
29
Teoh, Su Wooi. "The roles of pars flaccida in middle ear acoustic transmission." Thesis, Massachusetts Institute of Technology, 1996. http://hdl.handle.net/1721.1/39751.
Full text
30
Paduano, Mary Elizabeth. "Tuning of the middle ear in túngara frogs ( Engystomops pustulosus)." Scholarly Commons, 2014. https://scholarlycommons.pacific.edu/uop_etds/187.
Full textAbstract:
To effectively communicate using sound, animals have to hear well in the frequency range of their calls. In frogs, body size is a major predictor of both the dominant frequency of the mating call, and the frequency of best sensitivity of the ear, which tend to match each other. Various pathways are known to receive sound in frogs. Eardrums receive high-frequency sound, lungs receive low-frequency sound and forelegs, via the opercularis system, receive seismic frequencies. Túngara frogs are an anomaly among amphibians for having a low frequency mate-identification call, relative to their body size, but they also do not appear to fit the pattern of sound reception pathways described above. Using laser vibrometry, I evaluated the vibration response of the eardrum and body wall to airborne sound. The results revealed a clear mismatch between the tuning of both middle ear and lungs, and that of the brain, with the eardrums and lungs tuned to approximately 2500 Hz and the brain tuned to 500 Hz. Both eardrums and lungs are well tuned to receive chucks, an ornamental part of the call. However, a pathway that is tuned to the whine, which is the mate-identification call where the brain is tuned, has yet to be found.
31
Borgstein, J. A. "Surgical Observations on Atelectasis of the Middle Ear in Children." [S.l.] : Rotterdam : [The Author] ; Erasmus University [Host], 2009. http://hdl.handle.net/1765/15331.
Full text
32
Leblond, Catherine Louise. "Middle ear resonant frequency values in geriatric subjects : a multifrequency tympanometric study." Thesis, University of British Columbia, 1990. http://hdl.handle.net/2429/30014.
Full textAbstract:
Based on anatomical changes known to occur in the middle ear with aging, the purpose of this study was to compare middle ear resonant frequency values of geriatric subjects to those of young adults. Measurements were obtained with two different methods: sweep frequency tympanometry and discrete multifrequency tympanometry. Results from the two methods of measurement were also compared. Furthermore, intra-subject, inter-judge, and longitudinal reliability were examined for each measurement method.
Results showed no significant difference between the two age groups. However, resonant frequency values obtained with the two measurement methods differed significantly (p < 0.05). Intra-subject and longitudinal reliability measures were significantly higher for the discrete multifrequency method than for the sweep frequency method. Inter-judge reliability was 95% for both measurement methods.
We therefore concluded that age does not have a significant effect on middle ear resonant frequency values. It follows that normative resonant frequency data can be applied to adults of all age groups. Furthermore, the method used to measure resonant frequency has a significant effect on the values obtained, and comparisons of resonant frequency data should not be made across measurement methods. Although we were unable to determine which measurement method is most valid, the discrete multifrequency method is more reliable within subjects and over time.<br>Medicine, Faculty of<br>Audiology and Speech Sciences, School of<br>Graduate
33
Berge, Herbert van den. "The middle ear muscles of the rat morphological and functional aspects /." Maastricht : Maastricht : Datawyse ; University Library, Maastricht University [Host], 1990. http://arno.unimaas.nl/show.cgi?fid=6213.
Full text
34
Miron, Antonio Gonzalez. "The effect of auditory implants on the middle ear transfer function." Thesis, University of Reading, 2010. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.542255.
Full text
35
Chhan, David. "Role of middle-ear inertial component of bone conduction in chinchilla." Thesis, Massachusetts Institute of Technology, 2013. http://hdl.handle.net/1721.1/82381.
Full textAbstract:
Thesis (S.M.)--Massachusetts Institute of Technology, Dept. of Electrical Engineering and Computer Science, 2013.<br>Cataloged from PDF version of thesis.<br>Includes bibliographical references (p. 53-55).<br>Bone conduction describes the mechanisms that produce a hearing sensation when the skull bones are subjected to vibration. Multiple components and pathways have been suggested to contribute to total bone-conducted sound. They include outer-ear cartilaginous wall compression, middle-ear inertia, fluid inertia, cochlear capsule compression and soft-tissue conduction. Due to the complexity of the possible interactions within these components and pathways, the true stimulus to the inner ear is not fully understood nor has it been adequately quantified. In this thesis work, we examined the relationship between inner-ear sound pressures and its sensory response in addition to determining the relative significance between the outer, middle and inner ear mechanisms that are prominent in bone conduction hearing in chinchilla. Using both mechanical and physiological recording techniques, we measured cochlear responses in chinchilla before and after interruption of the middle-ear ossicular system in both air conduction (AC) and bone conduction (BC) stimulation. Our data suggest that differential intracochlear sound pressure is the driving source to the sensory response of the inner ear in AC and BC. Compared to those in AC, inner-ear sound pressure measurements in BC provide evidence of multiple mechanisms in BC process. After middle ear interruption, pressures in scala vestibuli Psv and scala tympani PST drop by as much as 40 dB in AC, but only decrease in Psv by 10 dB, with almost no change in PST in BC. The difference in the change of both Psv and PST in BC compared to AC suggest the main mechanisms that drive the inner ear response in BC are not derived from the outer ear or middle ear but the inner ear.<br>by David Chhan.<br>S.M.
36
Slama, Michaël C. C. (Michaël Charles Chalom). "Middle ear pressure gain and cochlear input impedance in the chinchilla." Thesis, Massachusetts Institute of Technology, 2008. http://hdl.handle.net/1721.1/44909.
Full textAbstract:
Thesis (S.M.)--Massachusetts Institute of Technology, Dept. of Electrical Engineering and Computer Science, 2008.<br>This electronic version was submitted by the student author. The certified thesis is available in the Institute Archives and Special Collections.<br>Includes bibliographical references (p. 35-37).<br>Measurements of middle ear conducted sound pressure in the cochlear vestibule PV have been performed in only a few individuals from a few mammalian species. Simultaneous measurements of sound-induced stapes velocity VS are even more rare. We report simultaneous measurements of VS and PV in chinchillas. The VS measurements were performed using single-beam laser-Doppler vibrometry; PV was measured with fiber optic pressure sensors like those described by Olson [JASA 1998; 103: 3445-63]. Accurate in-vivo measurements of PV are limited by anatomical access to the vestibule, the relative sizes of the sensor and vestibule, and damage to the cochlea when inserting the measurement device. The small size (170 [mu]m diameter) of the fiber-optic pressure sensors helps overcome these three constraints. PV and VS were measured in six animals, and the middle ear pressure gain (ratio of PV to the sound pressure in the ear canal) and the cochlear input impedance (ratio of PV to the product of VS and area of the footplate) computed. Our measurements of middle ear pressure gain are similar to published data in the chinchilla at stimulus frequencies of 500 Hz to 3 kHz, but are different at other frequencies. Our measurements of cochlear input impedance differ somewhat from previous estimates in the chinchilla and show a resistive input impedance up to at least 10 kHz. To our knowledge, these are the first direct measurements of this impedance in the chinchilla. The acoustic power entering the cochlea was computed based on our measurements of input impedance. This quantity was a good predictor for the audiogram at frequencies below 1 kHz.<br>by Michaël C.C. Slama.<br>S.M.
37
Robinson, Jamie. "The evolution of the early tetrapod middle ear and associated structures." Thesis, University College London (University of London), 2006. http://discovery.ucl.ac.uk/1445909/.
Full textAbstract:
This thesis utilises modern techniques to investigate the origin and evolution of hearing in tetrapods with particular emphasis on the evolution of the middle ear region of early tetrapods and the proposed relatives of lissamphibians. Recent advances in computed tomography (CT) scanning and 3D computer reconstruction has allowed the re-examination of many important specimens in the early tetrapod fossil record. The combination of CT scanning and 3D reconstruction has permitted the detailed visualisation of many aspects of these fossil specimens that could not have been easily achieved by traditional means. These modern techniques have been used to model the middle ear region in a range of early tetrapods. This was undertaken to investigate the form of the middle ear region in stem group tetrapods and temnospondyls, a group frequently cited in the origin of lissamphibians. The high resolution models created by the modem techniques have been utilised to investigate the function of the middle ear region in early tetrapods. Additionally, fossil evidence for the origin of the varied middle ear structures observed in the extant lissamphibians has been elucidated from the new models. Furthermore, these models allow the quantitative measurements of many aspects of the middle ear. The analysis of the new models has demonstrated that the support function for the stapes in early tetrapods has been overstated. A crude but transitional hearing function for the stapes is proposed for a range of stem group tetrapods. It is shown that temnospondyls, which are thought to possess tympanic membranes also appear to have possessed numerous specialisations of the middle ear present in extant lissamphibians.
38
Huang, Gregory T. (Gregory Tsan-Kao). "Measurement of middle-ear acoustic function in intact ears : application to size variations in the cat family." Thesis, Massachusetts Institute of Technology, 1999. http://hdl.handle.net/1721.1/79972.
Full textAbstract:
Thesis (Ph.D.)--Massachusetts Institute of Technology, Dept. of Electrical Engineering and Computer Science, 1999.<br>Includes bibliographical references (p. 189-196).<br>by Gregory T. Huang.<br>Ph.D.
39
Pieterse, Izabelle. "The hearing abilities and middle ear functioning of the recreational scuba diver." Diss., Pretoria : [s.n.], 2006. http://upetd.up.ac.za/thesis/available/etd-09112007-080225.
Full text
40
Van, Wijhe Rene G. "A finite element model of the middle ear of the moustached bat /." Thesis, McGill University, 2000. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=31074.
Full textAbstract:
Recently smooth-muscle tissue has been observed in the annular ligament of the moustached bat, Pteronotus parnellii. In order to lead to improved understanding of the function of this highly developed smooth-muscle system surrounding the tympanic membrane, a finite-element model was developed.<br>The complex geometry of the middle ear was defined using both magnetic-resonance microscopy and histological data. Contributions were made to the locally written software which was used for image segmentation and finite-element mesh generation.<br>The action of the smooth-muscle fibres is modelled by applying a radial load to the model of the tympanic membrane. The radial load is represented by placing load vectors tangential to the model of the tympanic membrane.<br>Simulations were carried out in order to investigate convergence, sensitivity to tympanic-membrane shape, and to evaluate the effects of pressure and radial loads.
41
Hüttenbrink, Karl-Bernd, Dirk Beutner, and Thomas Zahnert. "Clinical Results with an Active Middle Ear Implant in the Oval Window." Saechsische Landesbibliothek- Staats- und Universitaetsbibliothek Dresden, 2014. http://nbn-resolving.de/urn:nbn:de:bsz:14-qucosa-133983.
Full textAbstract:
Background: Some patients with chronic middle ear disease and multiple failed revisions, who also need a hearing aid, may benefit from an active middle ear implant. An advantage of an active middle ear implant is that the ear canal is unoccluded. Methods: Following extensive experimental development in temporal bones and investigations of various locations and attachments of a Vibrant Soundbridge transducer, a new titanium clip holder for the vibrant floating mass transducer was developed. This assembly is a total ossicular replacement prosthesis (TORP) that is placed on the stapes footplate. Six patients were implanted with this device. Results: Acoustic results demonstrate significantly improved gain, especially in the high frequencies, which is typically unobtainable by conventional hearing aids. Conclusion: The simple procedure of placing an active TORP assembly on the stapes footplate, similar to the implantation of a passive TORP prosthesis during tympanoplasty, offers promising treatment for cases of incurable middle ear disease<br>Dieser Beitrag ist mit Zustimmung des Rechteinhabers aufgrund einer (DFG-geförderten) Allianz- bzw. Nationallizenz frei zugänglich
42
Low, Robert Donald George. "Simultaneous recording of middle and inner ear function in normal hearing adults." Thesis, University of Sussex, 2001. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.394999.
Full text
43
Dobrev, Ivo Tsvetanov. "Full-field vibrometry by high-speed digital holography for middle-ear mechanics." Digital WPI, 2014. https://digitalcommons.wpi.edu/etd-dissertations/328.
Full textAbstract:
"Hearing loss affects approximately 1 in 10 people in the world and this percentage is increasing every year. Some of the most common causes of hearing loss are disorders of the middle-ear. Early detection and diagnosis of hearing loss as well as research to understand the hearing processes depend on medical and research tools for quantification of hearing capabilities and the function of the middle-ear in the complex acousto-mechanical transformation of environmental sounds into vibrations of the middle-ear, particular of the human tympanic membrane (TM or eardrum). Current ear exams assess the state of a patient’s hearing capabilities mainly based on qualitative evaluation of the healthiness of the TM. Existing quantitative clinical methods for description of the motion of the TM are limited to either average acoustic estimates (admittance or reflectance) or single-point displacement measurements. Such methods could leave examiners and researchers blind to the complex spatio-temporal response of the nanometer scale displacements of the entire TM. Current state-of-the-art medical research tools provide full-field nanometer displacement measurements of the surface of the human TM excited by steady state (tonal) stimuli. However, to fully understand the mechanics of hearing, and the complex acousto-mechanical characteristics of TM in particular, new tools are needed for full-field high-speed characterization of the nanometer scale displacements of the human TM subjected to impulse (wideband) acoustic excitation. This Dissertation reports the development of a new high-speed holographic system (HHS) for full-field nanometer transient (i.e., > 10 kHz) displacement measurement of the human middle-ear and the tympanic membrane, in particular. The HHS allows spatial (i.e., >500k data points) and temporal (i.e., > 40 kHz) resolutions that enable the study of the acoustical and mechanical characteristics of the middle-ear at a level of detail that have never been reached before. The realization of the HHS includes the development and implementation of novel phase sampling and acquisition approaches that allow the use of state-of-the-art high-resolution (i.e., >5 MP) and high-speed (> 80,000 fps) cameras through modular and expandable control architectures. The development of novel acquisition approaches allows the use of conventional speed (i.e., <20 fps) cameras to realize high-temporal resolutions (i.e., <15 us) at equivalent sampling rates of > 50,000 fps with minimum hardware cost and modifications. The design and implementation of novel spatio-temporal phase sampling methods utilize the high temporal resolution (i.e., < 5 us exposure) and frame rate (i.e., >80,000 fps) of high-speed cameras without imposing constraints on their spatial resolution (i.e., >20 um pixel size). Additionally, the research and in-vivo applications capabilities of the HHS are extended through the development and implementation of a holographic otoscope head (OH) and a mechatronic otoscope positioner (MOP). The large (i.e., > 1 GB with > 8x10^9 parameters) spatio-temporal data sets of the HHS measurements are automatically processed by custom parallel data mining and interpretation (PDMI) methods, which allow automatic quantification of medically relevant motion parameters (MRMPs), such as modal frequencies, time constants, and acoustic delays. Such capabilities could allow inferring local material properties across the surface of the TM. The HHS is a new medical tool that enables otologists to improve the quality of diagnosis and treatments as well as provides researchers with spatio-temporal information of the hearing process at a level of detail never reached before. "
44
Miller, Antonio John. "Using otoacoustic emissions to measure the transmission matrix of the middle-ear." Thesis, Massachusetts Institute of Technology, 2006. http://hdl.handle.net/1721.1/37979.
Full textAbstract:
Thesis (S.M.)--Harvard-MIT Division of Health Sciences and Technology, 2006.<br>Includes bibliographical references (leaves 39-41).<br>Here we describe an experimental method for measuring the acoustic transmission matrix of the middle-ear using otoacoustic emissions. The experiment builds on previous work that uses distortion product otoacoustic emissions (DPOAEs) as an intracochlear sound source to drive the middle-ear in reverse. This technique eliminates the complications introduced by needing to place an acoustic transducer inside the cochlea. Previous authors have shown how the complete 4x3 system response matrix, with its 12 unknowns, can be simplified to a 2x2 transmission matrix by de-coupling the middle-ear cavity and assuming the cochlear fluids are incompressible. This simplified description of middle-ear mechanics assumes that the input-output response at the tympanic membrane and stapes footplate is linear, one dimensional and time invariant. The technique allows for estimating the acoustic pressure and volume velocity at the tympanic membrane and the volume velocity of the stapes footplate, in both the forward and reverse direction, and under different boundary conditions at the stapes. The technique was applied to deeply anesthetized cats with widely opened middle-ear cavities over a frequency range of 200Hz to 10kHz. Results on three animals are reported and generally agree with previous data and a published middle-ear model.<br>by Antonio John Miller.<br>S.M.
45
Hüttenbrink, Karl-Bernd, Dirk Beutner, and Thomas Zahnert. "Clinical Results with an Active Middle Ear Implant in the Oval Window." Karger, 2010. https://tud.qucosa.de/id/qucosa%3A27554.
Full textAbstract:
Background: Some patients with chronic middle ear disease and multiple failed revisions, who also need a hearing aid, may benefit from an active middle ear implant. An advantage of an active middle ear implant is that the ear canal is unoccluded.
Methods: Following extensive experimental development in temporal bones and investigations of various locations and attachments of a Vibrant Soundbridge transducer, a new titanium clip holder for the vibrant floating mass transducer was developed. This assembly is a total ossicular replacement prosthesis (TORP) that is placed on the stapes footplate. Six patients were implanted with this device.
Results: Acoustic results demonstrate significantly improved gain, especially in the high frequencies, which is typically unobtainable by conventional hearing aids.
Conclusion: The simple procedure of placing an active TORP assembly on the stapes footplate, similar to the implantation of a passive TORP prosthesis during tympanoplasty, offers promising treatment for cases of incurable middle ear disease.<br>Dieser Beitrag ist mit Zustimmung des Rechteinhabers aufgrund einer (DFG-geförderten) Allianz- bzw. Nationallizenz frei zugänglich.
46
Davis, Lindsey Brooke. "Efficacy of Audiologic and Otologic Outcome Measures to Predict Middle Ear Status." Miami University / OhioLINK, 2003. http://rave.ohiolink.edu/etdc/view?acc_num=miami1050962431.
Full text
47
Feeney, M. Patrick, Lisa L. Hunter, Joseph Kei, et al. "Consensus Statement: Eriksholm Workshop on Wideband Absorbance Measures of the Middle Ear." Digital Commons @ East Tennessee State University, 2013. https://dc.etsu.edu/etsu-works/1799.
Full textAbstract:
On the final morning of the Workshop the participants discussed areas of consensus for the topic of the Workshop: Wideband Absorbance Measures of the Middle Ear. The discussion ranged across a number of topics and the following statements contain areas on which there was general agreement.
48
Wan, Ka-ki. "Tympanometric norms for Chinese young adults /." Hong Kong : University of Hong Kong, 2000. http://sunzi.lib.hku.hk/hkuto/record.jsp?B22008354.
Full text
49
Hoffstetter, Marc [Verfasser]. "Novel Designs for Middle Ear Implants : FEM based development and validation / Marc Hoffstetter." Aachen : Shaker, 2011. http://d-nb.info/1071529153/34.
Full text
50
Larsson, Christina. "Stiffness changes of the tympanic membrane in otitis media /." Stockholm : [Karolinska institutets bibl.], 2002. http://diss.kib.ki.se/2002/91-7349-224-8/.
Full text