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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.
81

Investigação radiológica e tomográfica da mandíbula de indivíduos com anomalias de 1º e 2º arcos faríngeos / Radiological and ct scan evaluation of mandible in patients with first and second pharingeal arches

Pittoli, Siulan Vendramini Paulovich 05 May 2011 (has links)
Introdução: O 1º e 2º arcos faríngeos contribuem com o desenvolvimento craniofacial e interferências no seu desenvolvimento podem resultar em alterações de gravidade variável, envolvendo maxila, mandíbula e orelha. Das anomalias associadas à malformação de orelha externa, a hipoplasia mandibular, o dermóide epibulbar e a anomalia de coluna cervical são as mais freqüentes e, este conjunto de sinais tem sido denominado espectro oculoauriculovertebral. O EOAV é uma condição heterogênea e complexa e o espectro de anomalias inclui desde microtia isolada até outras anomalias cranianas e extracranianas. Objetivo: analisar e descrever a morfologia da mandíbula, com ênfase na articulação temporomandibular (ATM) e investigar orelha média e interna em indivíduos com anomalias de 1º e 2º arcos faríngeos cadastrados no Serviço de Genética Clinica do HRAC USP. Indivíduos estudados e métodos: avaliação genética-clínica e avaliação por imagem enfocando orelha média, interna e côndilo mandibular foram realizadas em 56 indivíduos, cadastrados no Serviço de Genética Clínica do Hospital de Reabilitação de Anomalias Craniofaciais USP. O critério mínimo utilizado foi a presença de microtia isolada ou de microssomia hemifacial com malformação auricular leve, como apêndices pré-auriculares. Resultados e conclusão: anomalias envolvendo côndilo mandibular e/ou mandíbula e anomalias de orelha média mostraram alta freqüência (87.5% e 96.1%, respectivamente) nos indivíduos da presente casuística. Relação preditiva entre a ocorrência e a gravidade das anomalias de côndilo mandibular e/ou mandíbula com o acometimento da orelha externa e, relação preditiva para a ocorrência do acometimento do côndilo mandibular com a ocorrência de anomalias estruturais de orelha média e orelha interna foram observadas. Para a avaliação da ATM, a tomografia computadorizada foi considerada o exame de eleição. A investigação das estruturas do côndilo mandibular, da orelha média e interna deve fazer parte do protocolo de avaliação dos indivíduos com anomalias de 1º e 2º arcos faríngeos. / Introduction: The first and second pharingeal arches contribute to craniofacial development and interferences in normal development of these structures can result in maxillary, mandibular, and ear abnormalities. Mandible hypoplasia, epibulbar dermoids, and spinal vertebral defects are the most frequent anomalies combined with ear anomalies and this group has been called oculoauriculovertebral spectrum. This is a heterogeneous and complex condition that includes isolated microtia until other cranial and extracranial anomalies. Purpose: To analyze and describe the morphology of the mandible, with special approach to the temporomandibular joint and to investigate the middle and inner ear in patients with first and second pharyngeal arches involvement. Methods: Clinical genetics evaluation, radiological and CT scan evaluation with main focus in middle and inner ear structures as well as in mandible. This study was performed in fifty six patients at the Hospital of the Rehabilitation of the craniofacial anomalies USP. Minimal diagnostic criteria were the presence of preauricular tags or mild external ear anomaly associated to facial asymmetry. Results and Conclusions: Condyle and/or mandible and middle ear anomalies showed high frequency (87.5% and 96.1%) for the patients of the present study. Predictive relation between the occurrence and the gravity for condyle anomalies and/or mandible with involvement of the external ear was observed. Other predictive relation was observed between the occurrence of condyle anomalies with involvement of structural anomalies of middle and inner ear. CT scan proved to be the most appropriated tool for temporomandibular joint evaluation. Evaluation of condyle structures, middle and inner ear should be included in protocols for evaluation of conditions with first and second pharingeal arches involvement.
82

Topical anesthesia of the tympanic membrane : an experimental animal study

Schmidt, Sten-Hermann January 1987 (has links)
Myringotomy plays an important role in otological therapy. The procedure requires an efficient anesthesia, which can be obtained without general anesthesia. However, the use of local anesthetics on the tympanic membrane (TM) has been abandoned in many places, as general anesthesia has been readily available. In the present study the effects of some commonly used topical anesthetics on the TM structure and inner ear were tested in an animal model (rat and guinea pig).Four different anesthetic compounds—Xylocaine®, Bonain's liquid, phenol and Emla®—were applied to the TMs of the animals, which were sacrificed 10 minutes to 5 months after application. Morphological effects regarding time after treatment and number of applications were elucidated. At sacrifice the tissue was fixed and the TMs analysed by light microscopy (LM) and transmission electron microscopy (TEM). In nine animals phenol, Xylocaine® Spray or Emla® was applied to the round window niche and ABR recordings were made at 24 h to 6 months after exposure. After the final ABR evaluation the animals were sacrificed and the cochleae prepared for LM and scanning electron microscopy (SEM).On the TM phenol and Bonain's liquid caused instant destruction of the keratinizing stratified squamous epithelium followed by long-lasting hyperplasia of this epithelium and the underlying connective tissue. A pronounced hyperplasia of these two layers was also noted for the Xylocaine® Spray group, but without immediate destruction of the keratinizing epithelium. The extent of structural changes differed in relation to the extent of spreading of the agent. Emla® showed little, if any, sign of epithelial reaction and had no effect on the connective tissue. Regarding the inner ear Emla®, Xylocaine® Spray and phenol induced significantly impaired ABR thresholds mainly affecting the higher frequencies. However, the impaired ABR thresholds were reversible and at the end of the experiment there was no significant impairment compared to the control data. All agents, except Xylocaine®, damaged the hair cells in the basal part of the cochlea as shown by cytocochleogram and SEM analysis.Instant destruction of the epidermis seems to be necessary for an instant anesthetic effect. All agents caused profound connective tissue reactions. The manner of application, depending on the physical properties of the agent, determined the extent of the structural changes. The changes of the connective tissue were concentrated to the submucosal layer, which seems to be the area for reconstruction of the damaged TM. All agents caused functional inner ear changes. With the exception of Xylocaine® they also caused morphological alterations of the cochlea. The functional changes were partly reversible. Topical anesthetics applied to the TM should be used with caution and when used in an appropriate manner they can be considered safe, especially in an inflamed middle ear, with a thickened round window membrane, which should prevent the agents from reaching the inner ear structures. / digitalisering@umu
83

The effect of Nystatin on the inner ear : an experimental guinea pig study

Woods, Owen 08 1900 (has links)
Objectifs: Le Nystatin est un antibiotique efficace pour le traitement d’otomycose. Bien que sa sécurité au niveau de l’oreille externe soit bien établie, son utilisation n’est pas recommandée lorsqu’il y a une perforation tympanique. L’objectif de cette étude est d’évaluer le potentiel ototoxique du Nystatin lorsque celui-ci est appliqué directement au niveau de l’oreille moyenne. Méthodes: Nous avons fait une étude expérimentale avec 18 cochons d’Indes de souche Hartley que nous avons divisés en deux groupes. En exposant l’oreille moyenne de chaque animal au Nystatin (groupe I) ou à la néomycine (groupe II) et chaque oreille controlatérale à une solution physiologique (NaCl), la fonction auditive a été évaluée avec un test de potentiels évoqués auditif du tronc cérébral avant et après les injections. Une étude par microscopie électronique a permis une comparaison histologique de l’état des cellules ciliées cochléaires entre les 2 groupes. Résultats: Les pertes auditives moyennes du groupe « Nystatin » étaient de 13.0 dB et comparables aux pertes moyennes observées dans les oreilles ayant été injectées avec du NaCl (4.0 dB dans le groupe I et 15.1 dB dans le groupe II). Le groupe de contrôle « néomycine » a subi une perte auditive moyenne de 39.3 dB, ce qui représente une différence cliniquement et statistiquement significative (p<0.001). L’étude histologique avec une microscopie à balayage électronique a démontré une conservation de l’architecture des cellules ciliées cochléaires dans les groupe Nystatin et NaCl. La néomycine a causé une destruction marquée de ces structures. Conclusions: Le Nystatin ne provoque pas d’atteinte auditive ni de destruction des cellules ciliées externes après injection directe dans l’oreille moyenne chez le cochon d’Inde. / Objective: Nystatin is an effective topical antifungal agent widely used in the treatment of otomycosis. Though it is safe for external ear use, current recommendations are to avoid its use in cases of tympanic membrane perforation. The objective of our study was to test the security of Nystatin when applied directly to the middle ear of a guinea pig model. Methods: We performed an experimental study with 18 Hartley guinea pigs that were divided into two groups. Exposing middle ears from one group to Nystatin (group I) and from the other to the ototoxic neomycin (group II), we compared results of auditory brainstem response (ABR) testing at three intervals during the study. Each animal’s contralateral ear was injected with a physiological solution (NaCl). At the end of the study, we performed a histological analysis of the animals’ cochleae using a scanning electron microscope. Results: Average hearing loss in the Nystatin group was 13.0 dB which was similar to the results obtained in the NaCl-exposed ears (4.0 dB in group I and 15.1 dB in group II). Average hearing loss in the neomycin group was 39.3 dB, which represents a clinically significant difference (p<0.001). Scanning electron microscope evaluation revealed intact cochlear hair cell architecture in the Nystatin and normal saline groups, compared to important destruction in the neomycin group. Conclusion: Nystatin does not cause hearing impairment or cochlear hair cell damage when exposed directly to the middle ear of a guinea pig model.
84

Modelling of Components of the Human Middle Ear and Simulation of Their Dynamic Behaviour

Beer, Hans-Joachim, Bornitz, Matthias, Hardtke, Hans-Jürgen, Schmidt, Rolf, Hofmann, Gert, Vogel, Uwe, Zahnert, Thomas, Hüttenbrink, Karl-Bernd 03 March 2014 (has links) (PDF)
In order to get a better insight into the function of the human middle ear it is necessary to simulate its dynamic behaviour by means of the finite-element method. Three-dimensional measurements of the surfaces of the tympanic membrane and of the auditory ossicles malleus, incus and stapes are carried out and geometrical models are created. On the basis of these data, finite-element models are constructed and the dynamic behaviour of the combinations tympanic membrane with malleus in its elastic suspensions and stapes with annular ligament is simulated. Natural frequencies and mode shapes are computed by modal analysis. These investigations showed that the ossicles can be treated as rigid bodies only in a restricted frequency range from 0 to 3.5 kHz. / Dieser Beitrag ist mit Zustimmung des Rechteinhabers aufgrund einer (DFG-geförderten) Allianz- bzw. Nationallizenz frei zugänglich.
85

Identification of Parameters for the Middle Ear Model

Bornitz, Matthias, Zahnert, Thomas, Hardtke, Hans-Jürgen, Hüttenbrink, Karl-Bernd 03 March 2014 (has links) (PDF)
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. / Dieser Beitrag ist mit Zustimmung des Rechteinhabers aufgrund einer (DFG-geförderten) Allianz- bzw. Nationallizenz frei zugänglich.
86

Investigação radiológica e tomográfica da mandíbula de indivíduos com anomalias de 1º e 2º arcos faríngeos / Radiological and ct scan evaluation of mandible in patients with first and second pharingeal arches

Siulan Vendramini Paulovich Pittoli 05 May 2011 (has links)
Introdução: O 1º e 2º arcos faríngeos contribuem com o desenvolvimento craniofacial e interferências no seu desenvolvimento podem resultar em alterações de gravidade variável, envolvendo maxila, mandíbula e orelha. Das anomalias associadas à malformação de orelha externa, a hipoplasia mandibular, o dermóide epibulbar e a anomalia de coluna cervical são as mais freqüentes e, este conjunto de sinais tem sido denominado espectro oculoauriculovertebral. O EOAV é uma condição heterogênea e complexa e o espectro de anomalias inclui desde microtia isolada até outras anomalias cranianas e extracranianas. Objetivo: analisar e descrever a morfologia da mandíbula, com ênfase na articulação temporomandibular (ATM) e investigar orelha média e interna em indivíduos com anomalias de 1º e 2º arcos faríngeos cadastrados no Serviço de Genética Clinica do HRAC USP. Indivíduos estudados e métodos: avaliação genética-clínica e avaliação por imagem enfocando orelha média, interna e côndilo mandibular foram realizadas em 56 indivíduos, cadastrados no Serviço de Genética Clínica do Hospital de Reabilitação de Anomalias Craniofaciais USP. O critério mínimo utilizado foi a presença de microtia isolada ou de microssomia hemifacial com malformação auricular leve, como apêndices pré-auriculares. Resultados e conclusão: anomalias envolvendo côndilo mandibular e/ou mandíbula e anomalias de orelha média mostraram alta freqüência (87.5% e 96.1%, respectivamente) nos indivíduos da presente casuística. Relação preditiva entre a ocorrência e a gravidade das anomalias de côndilo mandibular e/ou mandíbula com o acometimento da orelha externa e, relação preditiva para a ocorrência do acometimento do côndilo mandibular com a ocorrência de anomalias estruturais de orelha média e orelha interna foram observadas. Para a avaliação da ATM, a tomografia computadorizada foi considerada o exame de eleição. A investigação das estruturas do côndilo mandibular, da orelha média e interna deve fazer parte do protocolo de avaliação dos indivíduos com anomalias de 1º e 2º arcos faríngeos. / Introduction: The first and second pharingeal arches contribute to craniofacial development and interferences in normal development of these structures can result in maxillary, mandibular, and ear abnormalities. Mandible hypoplasia, epibulbar dermoids, and spinal vertebral defects are the most frequent anomalies combined with ear anomalies and this group has been called oculoauriculovertebral spectrum. This is a heterogeneous and complex condition that includes isolated microtia until other cranial and extracranial anomalies. Purpose: To analyze and describe the morphology of the mandible, with special approach to the temporomandibular joint and to investigate the middle and inner ear in patients with first and second pharyngeal arches involvement. Methods: Clinical genetics evaluation, radiological and CT scan evaluation with main focus in middle and inner ear structures as well as in mandible. This study was performed in fifty six patients at the Hospital of the Rehabilitation of the craniofacial anomalies USP. Minimal diagnostic criteria were the presence of preauricular tags or mild external ear anomaly associated to facial asymmetry. Results and Conclusions: Condyle and/or mandible and middle ear anomalies showed high frequency (87.5% and 96.1%) for the patients of the present study. Predictive relation between the occurrence and the gravity for condyle anomalies and/or mandible with involvement of the external ear was observed. Other predictive relation was observed between the occurrence of condyle anomalies with involvement of structural anomalies of middle and inner ear. CT scan proved to be the most appropriated tool for temporomandibular joint evaluation. Evaluation of condyle structures, middle and inner ear should be included in protocols for evaluation of conditions with first and second pharingeal arches involvement.
87

Medidas de imitância acústica de banda larga em crianças com perda auditiva sensorial severa e profunda e diferentes achados timpanométricos / Wideband acoustic immittance measurements in children with severe and profound sensorineural hearing loss, and different tympanometric findings

Eliene Silva Araujo 27 February 2015 (has links)
A avaliação da integridade do sistema tímpano-ossicular é um pré-requisito para que o processo de diagnóstico audiológico infantil possa ser concluído com precisão, assim, muito têm se discutido em relação aos procedimentos utilizados na prática clínica para definir a presença ou ausência de problema condutivo. Nesse sentido, as medidas de imitância acústica de banda larga mostram-se como uma opção para o avanço na área. Diante disso, surgiu o interesse em ampliar os conhecimentos e trazer as características das medidas de imitância acústica de banda larga nas diferentes condições de orelha média. O objetivo do estudo foi caracterizar as medidas de imitância acústica de banda larga com os estímulos tom puro e chirp em crianças com perda auditiva sensorial de grau severo e profundo e diferentes padrões timpanométricos. Foram avaliadas 187 orelhas de 98 crianças na faixa etária de seis a 60 meses de idade, subdivididas em grupos de acordo com a pressão e compliância obtidas na timpanometria com sonda de 226 Hz. As medidas de imitância acústica de banda larga foram realizadas por meio do sistema de medidas do Acoustics\' Middle-Ear Power Analyzer - MEPA, versão 5.0, utilizando os estímulos tom puro e chirp, com faixa de frequência de 211 a 6000 Hz. Os valores de compliância e pressão obtidos na timpanometria convencional foram correlacionados às medidas de imitância acústica de banda larga, adotando-se testes estatísticos apropriados, com nível de significância de 0,05. Os resultados obtidos evidenciaram o efeito das faixas de frequência (grave, média e aguda) em todas as medidas analisadas, com exceção do delay da reflectância. Foi constatada influência de pressões correspondentes a -100 daPa ou mais negativas e também para pressões positivas acima de 25 daPa, e compliâncias menores que 0,2 ml nas medidas de imitância acústica de banda larga. Além disso, houve diferença significante entre os estímulos tom puro e chirp para frequências baixas para a absorvância e magnitude da impedância, com maior reflexo da variação dos valores de compliância e pressão nos resultados obtidos com estímulo chirp. Conclui-se que as características das medidas de imitância acústica de banda larga estão relacionadas à condição de orelha média e a frequência do estímulo teste. Para o delay da reflectância observou-se uma ampla variabilidade entre frequências ao analisar os grupos subdivididos pela pressão e também na frequência de 258 Hz ao analisar os grupos subdivididos pela compliância. / The evaluation of the integrity of the tympanic-ossicular system is a prerequisite for the child audiology diagnostic process to be completed accurately, thus, much has been discussed in relation to the procedures used in clinical practice to define the presence or absence of conductive problems. Hence, the wideband acoustic immittance measurements show to be an option to the advance in the field. As a result, the interest in expanding the knowledge and bringing the characteristics of wideband acoustic immittance measurements in the different conditions of middle ear, emerged. This study aimed at characterizing the wideband acoustic immittance measurements using pure and chirp stimuli in children presented with severe and profound sensorineural hearing loss and different tympanometric standards. 187 ears of 98 children in the age range six-sixty months, subdivided into groups according to pressure and compliance achieved through tympanometry with a 226 Hz probe, were assessed. Wideband acoustic immittance measurements were performed by the measuring system of the Acoustics\' Middle-Ear Power Analyzer - MEPA, version 5.0, using pure and chirp tone stimuli, in a frequency ranging from 211 to 6000 Hz. The values of compliance and pressure obtained through conventional tympanometry were correlated with wideband acoustic immittance measures, by applying suitable statistical tests, with a 0.05 significance level. The results achieved evidenced the effect of frequency bands (low, medium and high) in all measures examined, with the exception of the reflectance delay. The Influence of pressures -100 daPa or more negative ones and also in positive pressures above 25 Pa, and compliance lower than 0.2 ml in the wideband acoustic immittance measurements, was verified. In addition, there was a significant difference between pure tone and chirp stimuli at low frequencies for impedance absorbance and magnitude, with a greater reflex of the variation of compliance and pressure values in the results obtained with the chirp stimulus. It is concluded that the characteristics of broadband acoustic immittance measures are related to the condition of middle ear condition and the frequency of the test stimulus. For Reflectance delay, a wide variability between frequencies was observed when analyzing the groups subdivided by pressure and also in the frequency of 258 Hz, when analyzing the groups subdivided by compliance.
88

Acute otitis media in young children:randomized controlled trials of antimicrobial treatment, prevention and quality of life

Kujala, T. (Tiia) 08 September 2015 (has links)
Abstract The purpose of this study was to evaluate the effect of antibiotic treatment and surgery on acute otitis media (AOM), and to evaluate quality of life (QoL) among children with AOM and their parents. To evaluate the effectiveness of antibiotics, a total of 82 children with AOM were randomized for antibiotic or placebo treatment for 7 days. The duration of middle ear effusion was measured by daily tympanometry screenings at home over 2 weeks. Duration was also measured at clinical visits, including at entry, after 3 days, after 7 days, and then weekly until both ears were healthy according to pneumatic otoscopy or otomicroscopy, or for a maximum of 2 months. Among the group receiving antibiotics, middle ear effusion disappeared 2.0 weeks earlier than among those receiving placebo (P&lt;0.02). On day 14, 69% of children in the antibiotic group and 38% in the placebo group had normal tympanometry findings (P=0.02). On day 60, 5% of children in the antibiotic group and 24% in the placebo group had persistent middle ear effusion (P=0.01). The effect of surgery was assessed by randomly assigning 300 children with recurrent AOM, aged 10 months to 2 years, into 3 groups: 1. to receive ventilation tubes (VTs), 2. to receive VTs and adenoidectomy and 3. non-surgery. Follow-up of children occurred at clinical visits every 4 months for a 1-year period. If children suffered from upper respiratory symptoms or their parents suspected AOM during this period they were encouraged to receive additional follow-up care. Intervention was considered unsuccessful if a child had 2 AOM episodes in 2 months, 3 episodes in 6 months or persistent effusion lasting for 2 months. Intervention failed in 34% of children in the non-surgery group, 21% in the VT group (P=0.04 compared to non-surgery) and 16% in the group with VT and adenoidectomy (P=0.004 compared to non-surgery). QoL was assessed among 159 children participating in the study on the effect of surgery in children with recurrent AOM. We used disease-specific (Otitis Media-6) and generic instruments (Child Health Questionnaire-50) to measure QoL among children with AOM and their parents, and the effect of surgery on QoL. Children with AOM and their parents had a significantly poorer QoL than healthy children. QoL improved significantly at 1-year follow-up, but it did not reach the level observed in healthy children. Surgery did not have any additional impact on QoL. / Tiivistelmä Työn tavoitteena oli tutkia antibiootin ja kirurgian vaikutusta äkilliseen välikorvatulehdukseen sekä tutkia välikorvatulehduksia sairastavien lasten ja heidän vanhempiensa elämänlaatua. 82 äkillistä välikorvatulehdusta sairastavaa lasta satunnaistettiin saamaan joko antibiootti- tai lumelääkettä. Välikorvaeritteen poistumista seurattiin kotona päivittäisillä tympanometriamittauksilla kahden viikon ajan. Seurantakäynnit olivat yhden, kolmen ja seitsemän päivän kuluttua sekä viikoittain, kunnes korvat oli todettu terveiksi pneumaattisella otoskoopilla tai korvamikroskoopilla tai kahden kuukauden seuranta-aika päättyi. Välikorvaerite poistui kaksi viikkoa aikaisemmin antibiootti- kuin lumelääkkeellä (P&lt;0.02). Tympanometria normalisoitui kahden viikon kuluttua 69 %:lla antibioottiryhmästä ja 38 %:lla lumelääkeryhmästä (P=0.02). 60 päivän kuluttua välikorvaeritettä oli 5 %:lla antibioottiryhmästä ja 24 %:lla lumelääkeryhmästä (P=0.02). Kirurgian vaikuttavuutta toistuviin äkillisiin välikorvatulehduksiin tutkittiin satunnaistamalla 300 10–24 kk:n ikäistä lasta saamaan ilmastointiputket tai sekä ilmastointiputket että kitarisanpoisto tai ei kumpaakaan. Seurantakäynnit olivat neljän kuukauden välein vuoden ajan tai aina kun lapset sairastuivat ylähengitystietulehdukseen tai vanhemmat epäilivät välikorvatulehdusta. Interventio katsottiin epäonnistuneeksi (äkillisiä välikorvatulehduksia 2 / 2 kk, 3 / 6 kk tai jatkuva erite 2 kk) 34 %:lla ilman kirurgiaa hoidetuista lapsista, 21 %:lla ilmastointiputkiryhmän lapsista (P=0.04 verrattuna ilman kirurgiaa hoidettuihin) ja 16 %:lla lapsista, joille tehtiin sekä kitarisan poisto että asetettiin ilmastointiputket (P=0.004 verrattuna ilman kirurgiaa hoidettuihin). Elämänlaadun, äkillisen välikorvatulehduksen sekä siihen liittyvän kirurgian välistä yhteyttä selvitettiin 159 lapsella, jotka osallistuivat kirurgian vaikuttavuutta selvittävään tutkimukseen. Elämänlaatua mitattiin sekä tautikohtaisilla (Otitis Media-6) että yleistä elämänlaatua (Child Health Questionnaire-50) mittaavilla kyselylomakkeilla. Äkillistä välikorvatulehdusta sairastavilla lapsilla ja heidän vanhemmillaan oli merkittävästi huonompi elämänlaatu kuin terveillä. Elämänlaatu parani merkittävästi vuoden seuranta-aikana, mutta ei saavuttanut terveiden tasoa. Kirurgia ei tuonut mitään lisähyötyä elämänlaatuun.
89

Amplification acoustique par implant auditif électromagnétique : effet du couplage ossiculaire sur la fonction de transfert de l'oreille moyenne / Acoustic transfer using an active middle ear implant : effect on performance of the coupling to the middle ear

Devèze, Arnaud 11 June 2010 (has links)
La surdité est un problème de santé publique. Le vieillissement de la population explique ainsi une grande partie des causes de surdités, par la fréquence de la presbyacousie. Le principal moyen de la réhabilitation auditive est représenté par les prothèses auditives conventionnelles. Les aides auditives ont considérablement progressé ces dernières années, principalement en termes d’amélioration du traitement du signal. Ceci étant dit, outre le problème économique, certains facteurs limitent encore les bénéfices que les patients peuvent ressentir (occlusion du conduit auditif, effet larsen, absence d’amplification en ambiance sonore,…). Les implants d’oreille moyenne sont destinés à amplifier le signal sonore en le transmettant à l’oreille moyenne pour compenser une perte auditive. Ils sont indiqués en cas d’échec ou de contre-indication de l’appareillage conventionnel. Cependant, les implants d’oreille moyenne présentent certaines limites comme l’insuffisance de performance. Des données récentes montrent que les performances des techniques de réparation de la chaîne ossiculaire sont dépendantes du couplage des prothèses ossiculaires à la chaîne des osselets. Par ailleurs, des avancées dans la compréhension de la biomécanique de la chaîne ossiculaire confirment l’importance du placement et du couplage des procédés de restauration chirurgicaux. Nous avons formulé l’hypothèse selon laquelle ces données pouvaient être appliquées aux implants d’oreille moyenne pour en améliorer les performances. Nous avons voulu analyser expérimentalement les effets sur les performances de variables telles que : placement d’un transducteur, le couplage à la chaîne des osselets, la taille de l’effecteur, l’effet de stimulations alternatives. Nous avons utilisé un transducteur électromagnétique de dernière génération (Otologics MET-V Gen 2) et une technique d’analyse de la vibration des structures de l’oreille moyenne par vélocimétrie laser. Les résultats ont montré une nette amélioration des performances en fonction des modifications de placement et de couplage à la chaîne des osselets ou à la fenêtre ronde. / Hearing loss is a public health issue. Ageing is the most frequent cause of deafness. The main option for the rehabilitation of hearing loss is the use of conventional hearing aids. These aids have dramatically improved their performance for the past 20 years, mostly with regards to signal processing. However, in addition to economic reasons, some limitations remain (occlusion, feedback, hearing in noise…) and limit the satisfaction of patients. Active middle ear implants (AMEI) have been developed to overcome some of these problems and are indicated n conventional hearing failed to improve patients’ quality of hearing. However, AMEI suffer from limitations, as insufficient performances for severe hearing losses. Recent experimental and clinical data have highlighted the importance of coupling and placement of ossicular reconstruction passive prosthesis use. Other reported new findings regarding the biomechanism of the ossicular chain, especially for high frequency hearing, which is, unfortunately, where most people have their hearing loss. We hypothesized that these findings could be applied to AMEI use. We have analysed experimentally the effects on AMEI performance of variables such as: placement, coupling, size of tranduscer vibrating tip, alternative stimulation options. We used a electromagnetic tranducer from Otologics LLC to drive the middle ear or round window membrane, and a laser Doppler vibrometer to assess for the induced middle transfer function. Results have shown that we could provide great improvement in performance when varying the coupling method and the placement to the ossicular chain or the round window membrane.
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Long-Term Outcomes of Vibroplasty Coupler Implantations to Treat Mixed/Conductive Hearing Loss

Zahnert, Thomas, Mlynski, Robert, Löwenheim, Hubert, Beutner, Dirk, Hagen, Rudolf, Ernst, Arneborg, Zehlicke, Thorsten, Kühne, Hilke, Friese, Natascha, Tropitzsch, Anke, Luers, Jan Christoffer, Todt, Ingo, Hüttenbrink, Karl-Bernd 19 May 2020 (has links)
Objective: To evaluate the long-term safety and performance of four different vibroplasty couplers (round window, oval window, CliP and Bell coupler) in combination with an active middle ear implant. Methods: This was a multicentre, prospective, long-term study including 5 German hospitals. Thirty adult subjects suffering from conductive or mixed hearing loss were initially enrolled for the study, 24 of these were included in the final analysis with up to 36 months of postsurgical follow-up data. Bone conduction and air conduction were measured pre- and postoperatively to evaluate safety. Postoperative aided sound field thresholds and Freiburger monosyllable word recognition scores were compared to unaided pre-implantation results to confirm performance. Additional speech tests compared postoperative unaided with aided results. To determine patient satisfaction, an established quality-of-life questionnaire developed for conventional hearing aid usage was administered to all subjects. Results: Mean postoperative bone conduction thresholds remained stable throughout the whole study period. Mean functional gain for all couplers investigated was 38.5 ± 11.4 dB HL (12 months) and 38.8 ± 12.5 dB HL (36 months). Mean word recognition scores at 65 dB SPL increased from 2.9% in the unaided by 64.2% to 67.1% in the aided situation. The mean postoperative speech reception in quiet (or 50% understanding of words in sentences) shows a speech intelligibility improvement at 36 months of 17.8 ± 12.4 dB SPL over the unaided condition. The signal-to-noise ratio (SNR) improved by 5.9 ± 7.2 dB SNR over the unaided condition. High subjective device satisfaction was reflected by the International Inventory for Hearing Aids scored very positively. Conclusion: A significant improvement was seen with all couplers, and audiological performance did not significantly differ between 12 and 36 months after surgery.

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