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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
41

Consensus Statement: Eriksholm Workshop on Wideband Absorbance Measures of the Middle Ear

Feeney, M. Patrick, Hunter, Lisa L., Kei, Joseph, Lilly, David J., Margolis, Robert H., Nakajima, Hideko Heidi, Neely, Stephen T., Prieve, Beth A., Rosowski, John J., Sanford, Chris A., Schairer, Kim S., Shahnaz, Navid, Stenfelt, Stefan, Voss, Susan E. 01 January 2013 (has links)
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.
42

Hourly fluctuation of middle ear pressure as a function of age in school-age children

Henry, Susan Hogue 01 January 1989 (has links)
Tympanometry is a useful means of evaluating the status of the middle ear. For the pediatric population, tympanometry is particularly valuable for determining the presence of middle ear effusion. The test has been incorporated in many school hearing conservation programs because of its ease of administration, objectivity, and diagnostic value. In a study by deJonge and Cummings (1985), the hourly fluctuation of middle ear pressure was reported in a group of kindergarten-age children. The variability of middle ear pressure for that group of children averaged 150 daPa. In the present study, a maturational effect of this hourly fluctuation was observed between a group of first-grade age students and sixth-grade age students. Results indicated the younger group averaged a range of 145 daPa, correlating well with the deJonge and Cummings study, while the older group averaged a range of 92 daPa. Thus, as a child matures, the hourly fluctuation of middle ear pressure decreases significantly.
43

Transmyringeal middle ear ventilation : an experimental approach to evaluation of its benefits and consequences

Söderberg, Ove January 1985 (has links)
A prerequisite for a functioning middle ear is an air-filled middle ear cavity. Aeration of the middle ear cavity is controlled by the Eustachian tube. Dysfunction of the Eustachian tube has long been acknowledged as a significant etiological factor in disorders of the middle ear, especially middle ear effusions. Artificial ventilation of the middle ear through the tympanic membrane has been practised for almost two centuries, but with varying degrees of success. In 1954, Armstrong reintroduced the method of inserting a transmyringeal tympanostomy tube into the ear drum. Since that time this ventilatory device has gained wide popularity and several types of tube have been designed. However, an increasing number of clinical reports have shown treatment with tympanostomy tubes to be followed by complications such as tympanosclerosis, atrophy, persistent perforations and cholesteatomas. In the present thesis, experiments were outlined in which the tympanostomy tube - tympanic membrane interaction was studied and in which tympanostomy tubes were also applied in a well-defined type of otitis media. Furthermore, alternative transmyringeal ventilatory procedures such as myringotomies with a delayed healing time were investigated. The results were evaluated with morphological and microbiological methods. Repeated tympanostomy tube insertions in ears of healthy rats caused a remarkable thickening (about 30-fold) of the tympanic membrane of the tubulated quadrants, but even the untouched quadrants were affected. The thickened areas were characterized mainly by an increase in dense connective tissue which also contained sclerotic plaques. The structural changes in the tympanic membrane were still present 3 months after the final ventilation episode. Cleavage of the rat soft palate caused an immediate accumulation of effusion material in the tympanic cavity due to disturbance of Eustachian tube function. The fluid turned purulent within one to two weeks. The microbial flora of the middle ear cavity correlated well with that of the nasopharynx, indicating an ascending infection. Insertion of a tympanostomy tube could prevent the accumulation of effusion material in the meso- and hypotympanon and significantly suppress bacterial growth in the middle ear cavity. Thermal energy-inflicted myringotomies were tested as an alternative method for establishing transmyringeal ventilation. Myringotomies performed either with a CCL-laser or by diathermy showed a delayed healing pattern, most probably due to widespread destruction of the outer keratinized squamous epithelium and damage to the vascular supply. Upon comparison, laser myringotomies appeared more favourable due to their longer closure times, whereas the perforations accomplished by diathermy were often complicated by otorrhea and showed more advanced structural changes. / <p>Diss. (sammanfattning) Umeå : Umeå universitet, 1985, härtill 6 uppsatser.</p> / digitalisering@umu
44

Effects Of Scuba Diving On Middle Ear Pressure

Ozyurt, Deniz 01 April 2006 (has links) (PDF)
ABSTRACT EFFECTS OF SCUBA DIVING ON MIDDLE EAR PRESSURE &Ouml / zyurt, Deniz MS. Department of Physical Education and Sports Supervisor : Prof. Dr. Feza Korkusuz Co-Supervisor: Dr. Mehmet &Ouml / zekmek&ccedil / i April 2006, 42 pages Since / the self-contained underwater breathing apparatus (scuba) was developed / 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&amp / #8217 / s (12m) otoscopic inspections. In the first post dive tympanometric measurements / 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 / 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 / the correlation of .571 showed that 3m depth dives had grater frequency of middle ear pressure changes than 12m depth dives. Similarly / 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.
45

Classroom sound field amplification, listening and learning

Heeney, Michael Francis January 2007 (has links)
Research Doctorate - Doctor of Philosophy (PhD) / Sound field distribution is becoming increasingly known as a method to overcome problems associated with noise, distance, and reverberation in classrooms. No robust research on this intervention has been conducted in the New Zealand context. Changing pedagogies in the education of New Zealand children and young people have been observed particularly since the 1970’s, resulting in noisier classrooms (Wilson, 2000). Acoustic standards for New Zealand classrooms that were adopted in 2003 apply only to new or renovated classrooms, and not to the majority of existing classrooms (Ministry of Education, 2003a). This study investigated: (a) the efficacy of sound field distribution in 30 New Zealand classrooms from five schools and compared outcome measures with a representative control group; (b) the variations of benefit for groups from specific populations, in particular children from five different socio-economic backgrounds and those with histories of middle ear dysfunction; and (c) the effects on teachers who use this equipment. Data were collected from standardized objective measurement tools and from the teachers and students who were participating in the study. Results revealed that sound field distribution, with the equipment configuration of boom microphones and four speakers, can enhance the listening and learning environment resulting in significant positive benefits in raising the achievement levels of children and young people. These results were observed in listening comprehension, which has a flow-on effect on the overall scholastic achievement of all students. Evidence of improved outcomes in areas with a strong link to mastery of literacy were significant, in particular in the areas of phonologic skills, reading comprehension, and reading vocabulary. Results of the study strongly support the use of sound field distribution in all mainstream school settings irrespective of whether the children and young people belong to a particular ethnic group, have had a history of middle ear dysfunction, or attend schools of a particular socio-economic status. Classroom sound field distribution seemingly benefits all children and young people. As a result of the positive results of this study and given the stated goals for education by the New Zealand Ministry of Education (Ministry of Education, 2003b), sound field distribution needs to be considered at a policy level as an intervention to assist in reducing disparity and to improve learning outcomes for all young New Zealanders in mainstream school settings.
46

Experimental obstruction of the eustachian tube a contribution to knowledge of the pathogenesis of secretory otitis media /

Beek, Johan Marinus Herman van der, January 1981 (has links)
Thesis (doctoral)--Katholieke Universiteit te Nijmegen.
47

Perfil audiométrico da otite média crônica : análise de 745 orelhas

Braga, Maria Elisa Luce January 2014 (has links)
Dentre as doenças infecciosas que causam algum grau de comprometimento auditivo, a otite média é a mais prevalente. Esta é a patologia que mais frequentemente leva crianças ao atendimento médico. Quando não tratada adequadamente, suas complicações e sequelas podem persistir até a idade adulta, tornando-se crônica. Objetivo: comparar a perda auditiva resultante da Otite Média Crônica Supurativa (OMCS) colesteatomatosa e não colesteatomatosa entre crianças e adultos; comparar os valores de via aérea nas frequências de 250 a 8000Hz, entre crianças e adultos com OMCNC e OMCC; comparar os valores de via óssea nas frequências de 500 a 4000 Hz, entre crianças e adultos com OMCNC e OMCC; comparar os valores de gap aéreo-ósseos, nas frequências de 500 à 4000Hz, entre crianças e adultos com OMCNC e OMCC. Método: estudo transversal, observacional, comparativo e contemporâneo, com dados subindividuais (orelhas), tendo como sujeitos em estudo crianças e adultos com diagnóstico de OMCC ou OMCNC. Resultados e conclusões: os limiares de VA nas OMCNC nas frequências de 250 a 8000 Hz apresentaram-se significativamente menores nos pacientes pediátricos. No grupo de adultos, não houve diferença significativa nos limiares auditivos de VA. Os limiares de VO nas frequências de 500 a 4000 Hz apresentaram-se igualmente maiores no grupo dos adultos. No grupo pediátrico, não se observou diferença estatisticamente significativa entre os valores de VO. No grupo de crianças com OMCNC, os valores dos gap aéreo-ósseos nas frequências de 500 e 1000 Hz foram significativamente menores. Nos demais grupos, independentemente da faixa etária e do diagnóstico de OMCS, não foram encontradas diferenças estatisticamente significativas em nenhuma frequência testada entre os gap aéreo-ósseos. Considerando-se que o tempo de sintoma entre os adultos é maior, os resultados sugerem maior agressividade da OMCC entre as crianças em termos auditivos. / Among the infectious diseases that causes some degree of hearing loss, otitis media is the most predominant. This is the pathology that most often leads children to medical care and, if not treated properly, complications and sequels may persist into adulthood. Objective: Compare the values of air conduction thresholds (at frequencies from 250 to 8000Hz), bone conduction thresholds and air bone gap ( at frequencies from 500 to 4000Hz) among children and adults with Chronic suppurative otitis media (CSOM) with cholesteatoma (CCOM) and without cholesteatoma (NCCOM). Methods: Cross-sectional study, with 525 children and adults diagnosed with CCOM or NCCOM, submitted to pure tone audiometry. Results and Conclusions: The air conduction thresholds at frequencies of 250 to 8000 Hz were significantly lower in pediatric patients with NCCOM . Between adult groups, there was no significant difference in hearing in air bone threshold. The bone conduction thresholds at 500 to 4000 Hz were also higher in both adult groups. Between pediatric groups no statistically significant difference in bone conduction thresholds was observed. In the group of children with NCCOM values of air-bone gap at 500 and 1000 Hz were significantly lower. In the other groups, regardless of age and diagnosis of CSOM, no statistically significant differences were found in any frequency tested between the air-bone gap. Considering that the time of symptom among adults is higher, the results could suggest a more aggressive CCOM among children in hearing terms.
48

Estudo da função da tuba de eustáquio em pacientes com retrações da membrana timpânica e em indivíduos normais / Assessment of eustachian tube function in patients with tympanic membrane retraction and in normal subjects

Canali, Inesângela January 2013 (has links)
Introdução: O diagnóstico das disfunções da tuba auditiva é essencial para o melhor entendimento da patogênese da otite média crônica. Estão descritos, na literatura, uma série de testes que avaliam a função tubária, entretanto, entre eles, há uma diversidade metodológica que varia desde os protocolos de aplicação até a padronização dos testes e seus resultados. Objetivo: Avaliar a variação da pressão na orelha média em pacientes com retração da membrana timpânica e em indivíduos normais, durante a realização dos testes de função tubária, bem como avaliar a variação intraindividual desses testes. Este estudo também tem por objetivo avaliar o número de movimentações da membrana timpânica na orelha contralateral, durante a realização dos testes. Métodos: Estudo observacional do tipo transversal e contemporâneo, onde o fator em estudo foi a variação de pressão na orelha média, durante a realização dos testes de função tubária (Manobra de Valsalva, Sniff Test, Manobra de Toynbee) em indivíduos normais e em pacientes com retrações timpânicas leves e moderadas/severas. Foram incluídos 38 pacientes, totalizando 76 orelhas. Os pacientes foram submetidos, em dois momentos diferentes, aos testes de função tubária para determinar a medida da pressão após cada manobra. Durante a realização dos testes, videotoscopia era realizada concomitantemente na outra orelha, a fim de se observar a movimentação da membrana timpânica. A análise estatística foi realizada por meio do programa SPSS versão 18.0, em que foram considerados como estatisticamente significativos os valores de p< 0,05. Resultados: A média ± desvio-padrão da idade foi de 11 ± 2,72 anos; 55,3% dos pacientes foram do sexo masculino e 44,7% do sexo feminino. A prevalência de curva A foi maior nos grupos de orelhas normais e retrações leves, enquanto que de curva C foi maior no grupo de retrações moderadas/severas. Observamos aumento das pressões na orelha média durante a realização da Manobra de Valsalva no primeiro momento de avaliação nos três grupos de orelhas (p= 0,012). A variação da pressão não foi significativa nem para o Sniff Test, nem para o Toynbee nos dois momentos de avaliação (p≥0,05). A concordância das medidas nos dois diferentes momentos foi de fraca a moderada para os testes nos três grupos de orelhas, e as variâncias da discrepância entre as medidas foram maiores nas orelhas com retrações moderadas/severas. Apesar de não ter atingido significância estatística, o número de movimentações da membrana timpânica foi maior durante a manobra de Valsalva nos três grupos de orelhas. Conclusão: Na população estudada, a média das pressões na cavidade timpânica apresentou uma variação significativa somente durante a Manobra de Valsalva, no primeiro momento de avaliação, nos três grupos de orelhas. As orelhas normais e as com retração leve se comportaram de forma semelhante entre si em todos os testes. As manobras utilizadas apresentaram uma variação intraindividual de fraca a moderada, sendo que maior variação ocorreu em orelhas com retrações moderadas/severas. O número de movimentações da membrana timpânica foi maior durante a manobra de Valsalva nos três grupos de orelhas. / Introduction: The diagnosis of Eustachian tube dysfunctions is essential for better understanding the pathogenesis of chronic otitis media. The literature describes a series of tests to assess tube function; however, there is methodological diversity between them, which varies from application protocols to standardization of tests and their results. Objective: To evaluate the variation in middle ear pressure in patients with tympanic membrane retraction and in normal subjects during tube function tests, as well as to evaluate intra-individual variation between these tests. This study also aimed to evaluate the number of tympanic membrane movements of the contralateral ear during the tests. Methods: 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 normal subjects 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, in order to determine the measure of pressure after each maneuver. During the tests, videotoscopy was performed concomitantly in the contralateral ear, in order to observe tympanic membrane movement. Statistical analysis was performed using SPSS software, version 18.0, considering p values < 0.05 as statistically significant. Results: Mean ± standard deviation for age was 11 ± 2.72 years; 55.3% of patients were male and 44.7% female. The prevalence of type A tympanogram was higher in the groups with normal ears and mild retraction, while type C tympanogram was higher in the group with moderate/severe retraction. An increase in middle ear pressure was observed during Valsalva maneuver at the first time point evaluated in the three groups of ears (p= 0.012). The variation in pressure was not significant either for the Sniff Test or for Toynbee maneuver at the two time points evaluated (p≥0.05). The agreement of the measures at the two different time points was from weak to moderate for the tests in the tree groups of ears, and the variations in discrepancy between measures were higher in ears with moderate/severe retraction. Although it had not reached statistical significance, the number of tympanic membrane movements was higher during the Valsalva maneuver in the tree groups of ears. Conclusion: In this study population, mean pressure in the middle ear showed a 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 maneuvers used showed intra-individual variation from weak to moderate, with the higher variation occurring in ears with moderate/severe retraction. The number of tympanic membrane movements was higher during the Valsalva maneuver in the three groups of ears.
49

Perfil audiométrico da otite média crônica : análise de 745 orelhas

Braga, Maria Elisa Luce January 2014 (has links)
Dentre as doenças infecciosas que causam algum grau de comprometimento auditivo, a otite média é a mais prevalente. Esta é a patologia que mais frequentemente leva crianças ao atendimento médico. Quando não tratada adequadamente, suas complicações e sequelas podem persistir até a idade adulta, tornando-se crônica. Objetivo: comparar a perda auditiva resultante da Otite Média Crônica Supurativa (OMCS) colesteatomatosa e não colesteatomatosa entre crianças e adultos; comparar os valores de via aérea nas frequências de 250 a 8000Hz, entre crianças e adultos com OMCNC e OMCC; comparar os valores de via óssea nas frequências de 500 a 4000 Hz, entre crianças e adultos com OMCNC e OMCC; comparar os valores de gap aéreo-ósseos, nas frequências de 500 à 4000Hz, entre crianças e adultos com OMCNC e OMCC. Método: estudo transversal, observacional, comparativo e contemporâneo, com dados subindividuais (orelhas), tendo como sujeitos em estudo crianças e adultos com diagnóstico de OMCC ou OMCNC. Resultados e conclusões: os limiares de VA nas OMCNC nas frequências de 250 a 8000 Hz apresentaram-se significativamente menores nos pacientes pediátricos. No grupo de adultos, não houve diferença significativa nos limiares auditivos de VA. Os limiares de VO nas frequências de 500 a 4000 Hz apresentaram-se igualmente maiores no grupo dos adultos. No grupo pediátrico, não se observou diferença estatisticamente significativa entre os valores de VO. No grupo de crianças com OMCNC, os valores dos gap aéreo-ósseos nas frequências de 500 e 1000 Hz foram significativamente menores. Nos demais grupos, independentemente da faixa etária e do diagnóstico de OMCS, não foram encontradas diferenças estatisticamente significativas em nenhuma frequência testada entre os gap aéreo-ósseos. Considerando-se que o tempo de sintoma entre os adultos é maior, os resultados sugerem maior agressividade da OMCC entre as crianças em termos auditivos. / Among the infectious diseases that causes some degree of hearing loss, otitis media is the most predominant. This is the pathology that most often leads children to medical care and, if not treated properly, complications and sequels may persist into adulthood. Objective: Compare the values of air conduction thresholds (at frequencies from 250 to 8000Hz), bone conduction thresholds and air bone gap ( at frequencies from 500 to 4000Hz) among children and adults with Chronic suppurative otitis media (CSOM) with cholesteatoma (CCOM) and without cholesteatoma (NCCOM). Methods: Cross-sectional study, with 525 children and adults diagnosed with CCOM or NCCOM, submitted to pure tone audiometry. Results and Conclusions: The air conduction thresholds at frequencies of 250 to 8000 Hz were significantly lower in pediatric patients with NCCOM . Between adult groups, there was no significant difference in hearing in air bone threshold. The bone conduction thresholds at 500 to 4000 Hz were also higher in both adult groups. Between pediatric groups no statistically significant difference in bone conduction thresholds was observed. In the group of children with NCCOM values of air-bone gap at 500 and 1000 Hz were significantly lower. In the other groups, regardless of age and diagnosis of CSOM, no statistically significant differences were found in any frequency tested between the air-bone gap. Considering that the time of symptom among adults is higher, the results could suggest a more aggressive CCOM among children in hearing terms.
50

Ear morphlogy in Chinese bamboo rat (\kur{Rhizomys sinensis}): Hearing adaptations to subterranean environment

PLEŠTILOVÁ, Lucie January 2013 (has links)
I studied outer, middle and inner ear morphology in Chinese bamboo rat (Rhizomys sinensis).I compared studied specimen with other subterranean, fossorial and aboveground rodents and assumed degree of its adaptation to subterranean environment.

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