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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.
201

Effekter av kognitiv beteendeterapi vid tinnitusrelaterade besvär

Ekelund, Viktoria, Yin, Janina January 2009 (has links)
En tiondel av Sveriges befolkning är drabbade av tinnitus så chansen är stor att svenska sjuksköterskor träffar på individer drabbade av detta fenomen i sitt dagliga arbete. Syftet med denna studie var att öka kunskapen om tinnitus hos allmänsjuksköterskor och sjuksköterskestudenter, med två specifika frågeställningar. Den första var vilket bevis det finns för ett samband mellan tinnitus och depression, ångest, kognitiva besvär och sömnbesvär. Den andra frågeställningen handlade om på vilket sätt som kognitiv beteendeterapi har effekt på tinnitusrelaterade besvär. Metoden för den systematiska litteraturöversikten var Goodmans sju steg modifierad av Willman et al (2006), och ett modifierat protokoll av Carlsson & Eiman (2003) användes för att kvalitetsbedöma de artiklar som hittats i litteratursökningen. Resultatet byggde på tio kvantitativa artiklar. Svaga bevis fanns för ett samband mellan tinnitus och ångest, depression och sömnbesvär. Vad beträffar kognitiva besvär så visade resultatet att det fanns belägg för att tinnitus påverkar uppmärksamheten när den riktas åt flera håll. Kognitiv beteendeterapi hade effekt på tinnitus på så sätt att behandlingen reducerade besvär relaterade till tinnitus. Effekten av behandlingen analyserades med Lazarus copingstrategi som teoretisk referensram. Förslag på rekommendationer till implementering i vården är att då sjuksköterskan möter en patient med tinnitus bör sjuksköterskan förhöra sig om eventuella besvär, och vid behov rekommendera kognitiv beteendeterapi. / One-tenth of the Swedish population is affected by tinnitus so chances are that Swedish nurses will meet individuals affected by this phenomenon in their daily work. The aim of this study was to increase understanding concerning tinnitus in general nurses and nursing students, with two specific questions. The first one was what evidence there is that a relation between tinnitus and depression, anxiety, cognitions disorders and sleep disorders exists. The second question concerned how cognitive behavioral therapy has an effect on tinnitus-related complaints. The method for the systematic literature review was the seven steps of Goodman modified by Willman et al (2006), and a modified protocol by Carlsson & Eiman (2003) was used to assess the quality of the articles found in the literature search. The result is based on ten quantitative articles. There was weak evidence for a relationship between tinnitus and anxiety, depression and sleep disorders. As for cognition disorders, the results showed that there was support for tinnitus affecting attention when it is directed in several directions. The way that cognitive behavioral therapy was effective on tinnitus was that the treatment reduced complaints related to tinnitus. The effect of the treatment was analyzed with the coping-strategy of Lazarus as a theoretic frame. Suggestions for recommendations to the implementation of care is that when the nurse meets a patient with tinnitus should the nurse inquire about any inconvenience, and if there is a need recommend cognitive behavioral therapy.
202

In Vitro Cortical Networks for Disease Modeling and Drug Evaluation

Wu, Calvin 12 1900 (has links)
In translational research, disease models in preclinical studies are used as media for discovery of drugs or novel therapeutics. Development of in vitro models for various neurological diseases that enable efficient pharmacological or toxicological screening has been ongoing but challenging. Recognizing the potential benefit of in vitro disease models, dysfunctions in the cortical neuronal networks were induced to mimic the functional pathology of neurological symptoms using microelectrode arrays. Two different disease states – tinnitusand excitotoxicity – were investigated and discussed. In this model, pentylenetetrazol-induced increase in spontaneous firing rate and synchrony in the auditory cortical networks was used as correlate of tinnitus. Potential tinnitus treatment drugs from several different classes – including the novel class of potassium channel openers – were screened and quantified. The potentialtherapeutic values of these drugs were also discussed as the basis for drug repurposing. Functional excitotoxicity was induced by cisplatin (a cancer drug that causes neurological sideeffects) and glutamate (the major excitatory neurotransmitter). As proof-of-principle that the model may contribute to expediting the development of therapeutics, cisplatin excitotoxicity wasprevented by the antioxidant D-methionine, while glutamate excitotoxicity was prevented by ceftriaxone (a modulator of a glutamate reuptake transporter). In the latter part of the study, with results linking two of the screened drugs L-carnitine and D-methionine to GABAA receptor activation, it was demonstrated that this model not only served as an efficient drug-screening platform, but can be utilized to functionally investigate the underlying mechanism of drugs. Inaddition, several practical or conceptual directions for future studies to improve on this in vitro disease model are suggested.
203

Cortical Plasticity and Tinnitus

Chrostowski, Michal 10 1900 (has links)
<p>Tinnitus is an auditory disorder characterized by the perception of a ringing, hissing or buzzing sound with no external stimulus. Because the most common cause of chronic tinnitus is hearing loss, this neurological disorder is becoming increasingly prevalent in our noise-exposed and ageing society. With no cure and a lack of effective treatments, there is a need for a comprehensive understanding of the neural underpinnings of tinnitus. This dissertation outlines the development and validation of a comprehensive theoretical model of cortical correlates of tinnitus that is used to shed light on the development of tinnitus and to propose improvements to tinnitus treatment strategies.</p> <p>The first study involved the development of a computational model that predicts how homeostatic plasticity acting in the auditory cortex responds to hearing loss. A subsequent empirical study validated a more biologically plausible version of this computational model. The goal of these studies was to determine whether and how a form of plasticity that maintains balance in neural circuits can lead to aberrant activity in the auditory cortex. The final study extends the validated computational model to develop a comprehensive theoretical framework characterizing the potential role of homeostatic and Hebbian plasticity in the development of most major cortical correlates of tinnitus.</p> <p>These theoretical and empirical studies provide a novel and complete description of how neural plasticity in adult auditory cortex can respond to hearing loss and result in the development of tinnitus correlates.</p> / Doctor of Philosophy (PhD)
204

Selective noise cancelling application for misophonia treatment

Wunrow, Timothy 10 May 2024 (has links) (PDF)
Misophonia is a sensory disorder where specific stimuli, usually auditory, trigger the fight-flight-freeze response, causing extreme reactions, typically anger, panic, or anxiety. Research into treatment for misophonia is limited, primarily consisting of case studies applying common methods of therapy. However, research into similar disorders like tinnitus shows that there are many avenues of treatment that should be investigated, including audiological treatment. To apply audiological treatment to misophonia, selective noise cancelling must be used to control specific trigger sounds. In this research, a basic selective noise cancelling algorithm was developed using a convolutional neural network and was evaluated using a survey. Participants rated their reaction to trigger sounds, non-trigger sounds, and trigger sounds that had been selectively cancelled. The misophonic reactions to selectively cancelled sounds were significantly less than to trigger sounds. This shows that selective noise cancelling could be used to apply audiological treatments to misophonia.
205

Internet-Based Audiologist-Guided Cognitive Behavioral Therapy for Tinnitus: Randomized Controlled Trial

Beukes, Eldré W., Andersson, Gerhard, Fagelson, Marc, Manchaiah, Vinaya 14 February 2022 (has links)
BACKGROUND: Tinnitus is a symptom that can be very distressing owing to hearing sounds not related to any external sound source. Managing tinnitus is notoriously difficult, and access to evidence-based care is limited. Cognitive behavioral therapy (CBT) is a tinnitus management strategy with the most evidence of effectiveness but is rarely offered to those distressed by tinnitus. The provision of internet-based CBT for tinnitus overcomes accessibility barriers; however, it is not currently readily available in the United States. OBJECTIVE: The aim of this study is to investigate the efficacy of internet-based CBT compared with that of weekly monitoring for the management of tinnitus in reducing tinnitus distress; reducing tinnitus-related comorbidities, including tinnitus cognitions, insomnia, anxiety, and depression; and assessing the stability of the intervention effects 2 months after the intervention. METHODS: A 2-arm randomized clinical trial comparing audiologist-guided internet-based CBT (n=79) to a weekly monitoring group (n=79) with a 2-month follow-up assessed the efficacy of internet-based CBT. Eligible participants included adults seeking help for tinnitus. Recruitment was conducted on the web using an open-access website. Participants were randomized via 1:1 allocation, but blinding was not possible. The study was undertaken by English or Spanish speakers on the web. The primary outcome was a change in tinnitus distress as measured using the Tinnitus Functional Index. Secondary outcome measures included anxiety, depression, insomnia, tinnitus cognition, hearing-related difficulties, and quality of life. RESULTS: Internet-based CBT led to a greater reduction in tinnitus distress (mean 36.57, SD 22) compared with that in weekly monitoring (mean 46.31, SD 20.63; effect size: Cohen d=0.46, 95% CI 0.14-0.77) using an intention-to-treat analysis. For the secondary outcomes, there was a greater reduction in negative tinnitus cognition and insomnia. The results remained stable over the 2-month follow-up period. No important adverse events were observed. Further, 16% (10/158) of participants withdrew, with low overall compliance rates for questionnaire completion of 72.3% (107/148) at T1, 61% (91/148) at T2, and 42% (62/148) at T3. CONCLUSIONS: This study is the first to evaluate and indicate the efficacy of audiologist-delivered internet-based CBT in reducing tinnitus distress in a US population. It was also the first study to offer internet-based CBT in Spanish to accommodate the large Hispanic population in the United States. The results have been encouraging, and further work is indicated in view of making such an intervention applicable to a wider population. Further work is required to improve compliance and attract more Spanish speakers. TRIAL REGISTRATION: ClinicalTrials.gov NCT04004260; https://clinicaltrials.gov/ct2/show/NCT04004260.
206

Ressonância magnética funcional para avaliação do incômodo do zumbido em pacientes com audiometria normal / Analysis of tinnitus-related annoyance in patients with normal audiometry using functional magnetic resonance imaging

Alves, Silvia Cristina Batezati 08 December 2008 (has links)
INTRODUÇÃO: As terapias mais eficazes para zumbido são baseadas nos modelos psicológico e neurofisiológico, que teorizam que o incômodo existente é resultado da interação dinâmica dos centros auditivos, sistemas límbico e nervoso autônomo. Embora sejam amplamente aceitos na prática clínica, ainda necessitam validação científica. A ressonância magnética funcional (RMf) é um método objetivo capaz de identificar as áreas cerebrais descritas pelos modelos, como também a rede neural relacionada à percepção de estímulos emocionais, que ainda não foi investigada em estudos de zumbido. OBJETIVOS: 1) Baseado nos modelos que explicam o incômodo do zumbido, analisar as áreas corticais auditivas e não-auditivas em adultos normo-ouvintes com e sem zumbido, ativadas durante estimulação auditiva desagradável; 2) de acordo com a teoria da percepção de um estímulo emocional, avaliar se os pacientes com zumbido recrutavam a mesma rede neural para a percepção de sons desagradáveis que os indivíduos sem zumbido. MÉTODOS: Quinze pacientes com zumbido subjetivo crônico não-pulsátil (grupo zumbido, GZ) e 20 voluntários sem zumbido (grupo controle, GC), pareados por sexo e idade, foram submetidos à RMf (1.5 T). Os critérios de inclusão foram: indivíduos destros, audiometria normal, inventário de depressão de Beck < 20 pontos e escolaridade equivalente ao segundo grau completo. O paradigma incluiu sons do catálogo IADS (International Affective Digitized Sounds), validados para valência emocional e grau de estímulo, associado à escala análogo-visual SAM (Self Assessment Manikin), modificada para RMf. O paradigma foi praticado previamente em um simulador de RMf. A aquisição de imagens e a apresentação de estímulos foram realizadas através da técnica de seqüência de pulso com ruído acústico minimizado (SPRAM). RESULTADOS: O hipocampo esquerdo foi a área mais ativada no GC e não demonstrou atividade neural no GZ, no qual a maior ativação foi localizada na ínsula esquerda. Áreas auditivas (giro temporal superior e região ínfero-posterior do lobo temporal) e límbicas (ínsula) foram ativadas pelos sons desagradáveis em ambos os grupos. Na análise comparativa, a maior ativação no GZ ocorreu no cerebelo direito (p < 0,05) e, no GC, no giro temporal superior esquerdo e giro frontal inferior esquerdo (p < 0,05). CONCLUSÕES: A ativação paralela dos sistemas auditivo e límbico aos sons desagradáveis foi demonstrada nos pacientes com e sem zumbido. Entretanto, na comparação entre grupos, áreas límbicas e préfrontais não foram significantemente mais ativadas em pacientes com zumbido. Sugere-se que o cerebelo direito, recentemente relacionado à função cognitiva, pode ser a área não-auditiva envolvida no incômodo do zumbido. Especula-se que o incômodo do sintoma esteja relacionado a anormalidades na percepção emocional, seja pela identificação exacerbada (via ínsula) de sons desagradáveis ou pela ausência de regulação da resposta afetiva (via hipocampo) a este estímulo / INTRODUCTION: The most successful tinnitus therapies are based on the psychological and the neurophysiological models, which suggest that tinnitus-related annoyance results from the dynamic interaction of auditory brain centers, limbic and autonomic nervous systems. Although these models have been largely accepted in clinical practice, they lack experimental support and validation. Functional magnetic resonance imaging (fMRI) offers the opportunity to identify those brain regions pertinent to each model, and studies the neural network involved in the theory of emotion perception of stimuli. The latter has not been thoroughly investigated in tinnitus. OBJECTIVES: 1) Based on the models of developing tinnitus-related annoyance, analyze the cortical areas (auditory and non-auditory) in normal hearing individuals with and without tinnitus, activated by unpleasant auditory stimulation; and 2) according to the theory of emotion perception of acoustic stimulus, evaluate whether the patients with tinnitus were using the same neural network for perception of unpleasant sounds than the subjects without tinnitus. METHODS: Fifteen subjects with chronic subjective non-pulsatile tinnitus (tinnitus group, TG), and 20 healthy volunteers (control group, CG), matched for gender and age, were submitted to 1.5 T fMRI. Inclusion criteria consisted of normal pure-tone audiogram, righthandedness, Beck depression inventory < 20 points, and formal education level > 11 years. The paradigm comprised sounds from IADS (International Affective Digitized Sounds) with validated emotional valence and arousal, and a modified visual-analog Self Assessment Manikin (SAM) scale. All individuals previously practiced the task in a mock scanner. Image acquisition and stimuli presentation were designed using the silent event-related method, in which the scanner acoustic noise effects were minimized during brain activation detection. RESULTS: The left insula presented the highest neuronal activity in the TG, which showed no activity in the hippocampus. In the CG, the activation was markedly present in the left hippocampus, and was barely found in the insula. Unpleasant sounds activated auditory areas (superior temporal gyrus, inferior-posterior temporal lobe) and the limbic system (insula) in both groups. When the groups were compared, the right cerebellum was the most activated brain area in the TG (p < 0.05), and CG showed the highest activation in the left superior temporal gyrus and the left inferior frontal gyrus (p < 0.05). CONCLUSIONS: Parallel activation of auditory and limbic systems was demonstrated in both tinnitus and control patients. However, limbic and prefrontal areas were not significantly more activated in patients with tinnitus. The right cerebellum, recently described to have cognitive function, may be responsible for integrating the brain centers involved in the annoyance of tinnitus. In addition, we suggested that tinnitus-related annoyance may be secondary to emotion perception abnormalities, either a higher identification of emotional significance of the unpleasant sounds (via insula), or a lack of regulation of individual affective reaction (via hippocampus)
207

Associação entre o zumbido subjetivo, sinais e sintomas de disfunção temporomandibular e hábitos parafuncionais orais: um estudo transversal / Association between subjective tinnitus, TMD signs and symptoms and oral parafunctional habits: a croos-sectional study.

Saldanha, Aline Dantas Diógenes 07 April 2009 (has links)
Este trabalho objetivou avaliar a prevalência de subgrupos da Disfunção Temporomandibular (DTM) e hábitos parafuncionais orais em indivíduos portadores de zumbido subjetivo, sendo comparados com indivíduos sem zumbido. Duzentos indivíduos, de ambos os gêneros, com idade entre 18 a 60 anos, participaram do estudo. Inicialmente, foram subdivididos, com auxílio do exame otorrinolaringológico, em grupo experimental (n=100), indivíduos portadores de zumbido subjetivo, e grupo controle (n=100), voluntários sem qualquer queixa de zumbido. A análise da prevalência de DTM, bem como o estudo dos seus sinais e sintomas, foi feita segundo os critérios de diagnóstico Research Diagnostic Criteria for Temporomandibular Disorders (RDC/TMD). O Limiar de Dor à Pressão (LDP) dos músculos masseter e temporais (anterior, médio e posterior) foram medidos bilateralmente, por meio de um algômetro KRATOS®, e a dor subjetiva pela Escala de Análise Visual (EAV). O estudo da presença dos hábitos parafuncionais orais, apertamento dentário diurno e bruxismo do sono, foi feito através do auto-relato e da aplicação de exame clínico de bruxismo, respectivamente. Os dados obtidos foram submetidos à análise estatística (Testes Qui-Quadrado, t de Student e Mann-Whitney e Coeficiente de Correlação de Spearman), em um nível de significância de 5%. Foi encontrada uma maior prevalência de DTM no grupo experimental quando comparado ao grupo controle (p<0,05). De uma maneira geral, os sinais e sintomas de DTM avaliados foram mais prevalentes no grupo experimental em comparação ao grupo controle, como a presença de dor à palpação na ATM e de ruídos articulares na abertura bucal, maior tempo de dor e maior grau de severidade de dor crônica. O resultado médio da EAV encontrado foi estatisticamente maior no grupo experimental (p<0,05), contudo os LDPs não apresentaram diferença significativa entre os grupos. A análise dos hábitos parafuncionais mostrou diferença estatisticamentente significativa da presença de bruxismo noturno entre os grupos, sendo mais prevalente no grupo experimental (p<0,05). Houve uma correlação positiva estatisticamente significativa entre a severidade do zumbido e a severidade da dor crônica (p<0,05) e entre o tempo de zumbido e o tempo de dor (p<0,05). Conclui-se que parece existir uma forte correlação entre os sinais e sintomas da DTM e o zumbido de caráter subjetivo. / The aim of this study was to study the prevalence of Temporomandibular Disorders (TMD) subgroups and oral parafunctional habits, daytime clenching and sleep bruxism, in patients with subjective tinnitus when compared to a group of asymptomatic volunteers. Two hundred patients (ages between 18-60 years-old) participated in this study, divided into two groups, according to the presence (experimental) or not (comparison) of subjective tinnitus. According to the RDC/TMD criteria, the subgroups were determined. The Pain Pressure Threshold (PPT) values of masseter and temporalis (anterior, middle, and posterior regions) muscles were recorded bilaterally with an algometer and a visual analog scale (VAS) was used to address subjective pain. The severity of the TMD was determined by using an anamnestic questionnaire while a self-reported questionnaire detected parafuncional habits. Data were submitted to statistical analysis (Chi-square, t Student, Mann-Whitney and Spearmans Correlation), at a 5% significance level. The prevalence of signs and symptoms of TMD was significantly associated with the presence of tinnitus (p.001). The three most prevalent TMD subgroups in tinnitus patients (p<.05) were myofascial pain with temporomandibular joint (TMJ) internal derangement (39%), disc displacement with reduction (44,33%) and arthralgy (53,54%). The PPT values were lower (p>.05) while VAS was statistically higher (p<.05) for tinnitus patients. The severity of TMD was associated with tinnitus (p0.001). Both, the report of sleep bruxism (58%), as well as of daytime clenching (60%) were found more frequently in tinnitus patients. Significant difference, however, was detected only for the report of bruxism (p<.05). These results suggest that an association exists between TMD and subjective tinnitus.
208

"Estudo das vias auditivas eferentes em indivíduos com zumbido" / Study of efferent auditory pathways in subjects with tinnitus

Favero, Mariana Lopes 30 March 2004 (has links)
Uma ativação do trato olivococlear medial reduz a amplitude das emissões otoacústicas de forma lateralizada, com um predomínio à direita. Pessoas com zumbido teriam uma disfunção do reflexo eferente, mas esses resultados não foram comprovados em todas as pesquisas. Curiosamente, estas pesquisas não valorizam a lateralidade eferente. Comparamos a supressão na orelha direita de pessoas com e sem zumbido e a lateralidade do sistema eferente pela análise da supressão à direita e à esquerda no grupo sem zumbido. Concluímos que há relação entre zumbido e não supressão e que à direita, a supressão é maior / An activation of the medial olivocochlear tract reduces the amplitude of otoacoustic emissions with predominance of the right side. Subjects with tinnitus would have an abnormality of the suppressing reflex, but such results have not been confirmed yet in any study. Curiously, such studies did not value the functional laterality. We compared right ear suppression of people with and without tinnitus, and the suppression on the right and on the left in the group without tinnitus. We concluded that there was a relation between tinnitus and absent suppression of otoacoustic emissions and right ear suppression was more marked.
209

Eletrofisiologia da audição em indivíduos com vestibulopatias periféricas pré e pós reabilitação vestibular / Electrophysiological evaluation of hearing in individuals with peripheral vestibular disorders before and after vestibular rehabilitation therapy

Nunes, Cristiane da Silva 12 September 2011 (has links)
INTRODUÇÃO: Os Potenciais Evocados Auditivos avaliam a atividade neuroelétrica da via auditiva desde o nervo auditivo até o córtex cerebral. A vectoeletronistagmografia permite analisar os canais semicirculares e/ou nervo vestibular inferior, verificando se existe comprometimento vestibular periférico ou central. A reabilitação vestibular é composta de exercícios físicos ativos e repetitivos de olhos, cabeça e corpo e/ou manobras específicas que visam diminuir a tontura e a instabilidade corporal, aumentar a estabilização no olhar, o controle postural e melhorar o bem-estar na realização das atividades do diaa- dia. Levando-se em conta a escassez de trabalhos na literatura que investiguem a via auditiva central em indivíduos com síndrome vestibular periférica e que sejam submetidos à reabilitação vestibular, torna-se importante conhecer o funcionamento do sistema auditivo central, desde o tronco encefálico até o córtex auditivo, em indivíduos com vestibulopatias periféricas. OBJETIVOS: caracterizar os potenciais evocados auditivos de curta, média e longa latências em indivíduos com vestibulopatias periféricas, bem como verificar a evolução destes potenciais e dos resultados obtidos no Dizziness Handicap Inventory (DHI) frente à reabilitação vestibular. MÉTODOS: Foram submetidos à avaliação eletrofisiológica da audição por meio dos potenciais evocados auditivos de tronco encefálico (PEATE), potencial evocado auditivo de média latência (PEAML) e potencial cognitivo (P300), bem como à aplicação do questionário DHI, antes e após reabilitação vestibular, 20 indivíduos com diagnóstico de Síndrome Vestibular Periférica Irritativa (SVPI) e 17 indivíduos com diagnóstico de Síndrome Vestibular Periférica Deficitária (SVPD), com idades entre 20 e 70 anos. RESULTADOS: Os resultados demonstraram que o grupo com SVPD apresentou maior porcentagem de resultados alterados no PEATE e PEAML. No que diz respeito aos tipos de alterações, pode-se observar no grupo com SVPD, alteração em tronco encefálico baixo no PEATE pré e pós RV; aumento das latências das ondas Na e Pa no PEAML pós RV, aumento da latência da onda Pa pré RV e efeito eletrodo para a amplitude Na- Pa pós RV. No grupo com SVPI, foi observada alteração do tipo outros no PEATE pré RV; aumento da latência da onda Pa no PEAML pré e pós RV e ambas as alterações para a amplitude Na-Pa pós RV. No estudo da evolução dos resultados pré e pós RV, pode-se observar maior porcentagem de resultados semelhantes para os três potenciais, em ambos os grupos avaliados. Na comparação do DHI pré e pós RV, ocorreram melhores resultados para os aspectos físico, emocional e funcional no grupo com SVPI e para os aspectos físico e emocional no grupo com SVPD. Tornam-se necessários mais estudos que avaliem a via auditiva central destes indivíduos para uma melhor caracterização dos achados eletrofisiológicos / INTRODUCTION: The auditory evoked potentials assess the neuroelectrical activity of the auditory pathway from the auditory nerve to the cerebral cortex. The vectoelectronystagmography analyzes the semicircular canals and/or inferior vestibular nerve, checking peripheral or central vestibular involvement. The vestibular rehabilitation therapy consists in active exercises and repetitive eyes exercises, head and body and/or specific maneuvers to reduce the dizziness and body instability, increase gaze stability and postural control and also improve well-being in daily activities. Taking into account the scarcity of studies in the literature that investigate the central auditory pathways in subjects who underwent vestibular rehabilitation therapy, it becames important to know the central auditory system from the brainstem to the auditory cortex, in subjects with peripheral vestibular disorders. OBJECTIVE: To characterize the auditory evoked potentials of short, middle and long latencies in subjects with peripheral vestibular disorders, as well as to evaluate the development of these potentials and the results obtained in the Dizziness Handicap Inventory (DHI) after vestibular rehabilitation therapy (VRT). METHODS: brainstem auditory evoked potential (BAEP), Auditory Middle- Latency Response (AMLR), cognitive potential (P300) and DHI were carried out in 20 subjects with Peripheral Vestibular Hyperfunction Syndrome and 17 subjects with Peripheral Vestibular Hypofunction Syndrome, aged between 20 and 70, before and after vestibular rehabilitation therapy. RESULTS: The results showed that the Peripheral Vestibular Hypofunction Syndrome group, presented higher percentage of altered results on BAEP and AMLR. Comparing the normal and altered results (qualitative analysis) between the groups in the BAEP, lower brainstem was predominantly observed in the Peripheral Vestibular Hypofunction Syndrome group before and after VRT; increased latencies of Na and Pa waves in AMLR after VRT, incresead latency of Pa wave in AMLR before VRT and electrode effect to the Na-Pa amplitude after VRT. The alteration predominantly observed in the Peripheral Vestibular Hyperfunction Syndrome group, was the other type one before VRT; increased latency of Pa wave in AMLR before and after VRT and both changes to the Na-Pa amplitude after VRT. In the study of the evolution before and after VRT, it was observed a higher percentage of similar results for the three potentials in both groups. Comparing results before and after VRT, the DHI greatest improvement occurred for the physical, emotional and functional aspects in the Peripheral Vestibular Hyperfunction Syndrome group and for the physical and emotional aspects in the Peripheral Vestibular Hypofunction Syndrome group. Further studies that evaluate the central auditory pathway of individuals with peripheral vestibular syndrome are needed to better characterize the electrophysiological findings
210

Eficácia da estimulação magnética transcraniana em pacientes com zumbido e audiometria normal: avaliação clínica e por neuroimagem / Transcranial magnetic stimulation efficiency in patients with tinnitus and normal pure-tone audiometry: clinical and neuroimaging evaluation.

Renata de Almeida Marcondes 11 March 2009 (has links)
INTRODUÇÃO: O zumbido é um sintoma muito freqüente e de difícil tratamento. Atualmente, algumas evidências mostraram que o zumbido está associado a alterações funcionais do sistema nervoso central. Nos últimos anos, a modulação da atividade cortical relacionada ao zumbido por meio da estimulação magnética transcraniana repetitiva (EMT) tem sido proposta como um tratamento promissor. Entretanto, nenhum estudo avaliou sua eficácia no controle do zumbido em pacientes sem perda auditiva concomitante, nem seu efeito de longa duração. O objetivo do trabalho foi investigar os efeitos imediatos e a longo prazo da estimulação magnética transcraniana repetitiva de baixa freqüência (1 Hz) em pacientes com zumbido e audiometria normal. MÉTODOS: Utilizando um ensaio clínico aleatorizado, duplo cego e paralelo, foram randomizados 20 pacientes para receber a EMT ativa ou placebo. A estimulação foi aplicada no córtex têmporo-parietal esquerdo por cinco dias consecutivos. A avaliação clínica foi feita por meio do Tinnitus Handicap Inventory e da escala análogo-visual. A avaliação por neuroimagem foi feita por meio do SPECT, o qual foi realizado antes e 14 dias após o período de estimulação. RESULTADOS: Clinicamente, o grupo submetido à estimulação magnética transcraniana ativa apresentou uma melhora significativa do zumbido, mantida por até seis meses, quando comparado ao grupo que recebeu a estimulação placebo. A avaliação por SPECT demonstrou redução do fluxo sanguíneo no lobo temporal esquerdo após o período de estimulação ativa. CONCLUSÃO: Os resultados revelam o potencial terapêutico da estimulação magnética transcraniana como nova ferramenta no tratamento do zumbido, proporcionando redução significativa do incômodo provocado pelo zumbido por até seis meses e reduzindo a atividade neuronal no córtex temporal. / INTRODUCTION: Tinnitus is a frequent disorder which is very difficult to treat. There is compelling evidence that tinnitus is associated with functional alterations in the central nervous system. Recently, the targeted modulation of tinnitus-related cortical activity through repetitive transcranial magnetic stimulation (rTMS) has been proposed as a promising new treatment approach. However, its efficacy in patients without hearing loss has never been studied, as well as the long-term duration of its effect. The objective of this study was to investigate both immediate and long-term effect of low frequency (1 Hz) rTMS in patients with tinnitus and normal hearing. METHODS: Using a randomized double-blind and parallel clinical trial, 20 patients were divided to receive either active or placebo transcranial magnetic stimulation over the left temporoparietal cortex for 5 consecutive days. The clinical evaluation was performed by using the Tinnitus Handicap Inventory and the visual analogue scale. The neuroimage evaluation included and ECD-SPECT imaging, which was performed before and 14 days after rTMS. RESULTS: From the clinical point of view, the group submitted to active rTMS presented significant improvement of the tinnitus score, which was sustained up to six months, when compared to the group that received the sham rTMS. SPECT measurements demonstrated a reduction of metabolic activity in the left temporal lobe after active rTMS. CONCLUSION: These results support the potential of rTMS as a new therapeutic tool for the treatment of chronic tinnitus, by demonstrating a significant reduction of tinnitus complaints over a period of at least six months and a significant reduction of neural activity in the temporal cortex.

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