Introducción: La evolución y el pronóstico de la sordera brusca ha sido relacionada con diversos factores de pronóstico como la edad, el grado de pérdida auditiva, el retraso diagnóstico, la curva audiométrica, los factores de riesgo cardiovascular, los acúfenos y la clínica vertiginosa. Los potenciales evocados vestibulares miogénicos (PEVM) valoran el sáculo y el nervio vestibular inferior y detectan enfermedades vestibulares periféricas, incluso en ausencia de vértigo. La proximidad anatómica entre la cóclea y el vestíbulo explicaría que un daño coclear severo se asociase a una afectación del sáculo. Así, a mayor daño cocleo-vestibular peor recuperación auditiva. Los PEVM permitirían detectar la afectación vestibular, incluso en ausencia de vértigo, y pronosticar la recuperación auditiva. Hipótesis: La afectación de los potenciales evocados vestibulares miogénicos (PEVM) en la sordera brusca es un factor de mal pronóstico. Diseño del estudio: Prospectivo observacional transversal. Material y método: Durante el período de tiempo comprendido entre agosto de 2008 y julio de 2010 se incluyeron en el estudio 73 pacientes que acudieron al servicio de urgencias de ORL del Hospital Vall d’Hebron con diagnóstico audiométrico de hipoacusia brusca. La pérdida auditiva se obtuvo mediante la 5PTA y se clasificó según la escala cuantitativa de la SEORL. La recuperación auditiva se calculó en valor absoluto, considerando recuperación cuando la ganancia fue mayor de 15 dB, y se distinguieron grados según la clasificación de Siegel. Los PEVM fueron normales o patológicos, clasificándose los patológicos en anomalías de amplitud, anomalías de latencia, ausencia de respuesta o no valorables. Para el análisis estadístico se utilizó la prueba chi-cuadrada para las variables cualitativas y la ANOVA para las cuantitativas. Se realizó un estudio multivariante para las variables relacionadas con la recuperación auditiva mediante un modelo de regresión logística. Resultados: La incidencia de PEVM alterados fue del 43%. Se observó una relación estadísticamente significativa entre la recuperación auditiva y los PEVM (p<0.05). El 70% de los pacientes con PEVM normales recuperó audición. El 60% con recuperación completa presentó PEVM normales. Ningún paciente con recuperación completa o moderada había presentado ausencia de potencial. Por otro lado, los pacientes sin clínica vertiginosa obtuvieron PEVM normales o de menor amplitud y los pacientes con un PEVM ausente habían manifestado vértigo. Discusión: Coincidiendo con otros autores (Iwasaki, Wang, Korres) se observa una relación estadísticamente significativa entre los PEVM y la recuperación auditiva. Así, un PEVM normal o de menor amplitud no es indicativo de recuperación auditiva. Sin embargo, un PEVM ausente o no valorable es signo de mal pronóstico y peor recuperación auditiva. En relación a los PEVM y la clínica vestibular, según algunos autores (Stamatiou, Iwasaki), la presencia de alteraciones vestibulares en la sordera brusca parece correlacionarse mejor con la afectación sacular que con una disfunción aislada de los canales semicirculares. Conclusión: Los PEVM permiten detectar la afectación vestibular, incluso en ausencia de vértigo, y predecir una mayor extensión del daño y una peor recuperación auditiva en los pacientes con sordera brusca. / Introduction: The prognosis and evolution of sudden sensorineural hearing loss (SSHL) have been related to several prognostic factors such as age, the severity of hearing loss, a delayed diagnosis, the shape of the audiometric curve, cardiovascular risk factors, tinnitus and dizzyness. Vestibular evoked myogenic potential testing (VEMP) assesses the neural pathway mediated by the saccule and the inferior branch of the vestibular nerve. The anatomical proximity between the cochlea and vestibule may explain an involvement of the saccule when a cochlear damage. The likelihood of hearing recovery tends to reduce as the degree of labyrinthine involvement increases. VEMP may detect vestibular impairment, even in the absence of vertigo, and predict hearing recovery Hypothesis: The abnormal VEMP response is a factor of poor prognosis in sudden sensorineural hearing loss. Study Design: A prospective observational study. Material and methods: From August 2008 to July 2010, 73 patients with audiometric diagnosis of sudden sensorineural hearing loss were included in the study. All of them were attended at the Vall d’Hebron Hospital Emergency Room of ENT. Hearing loss was defined by 5PTA and was classified according to the quantitative scale established by the Spanish Society of Otorhinolaryngology. Hearing recovery was defined as a gain equal or greater than 15 dB at 5PTA. A subclassification was made using the Siegel classification of hearing recovery. VEMP results were normal or abnormal. Chi-square analysis was peformed to qualitative variables and ANOVA analysis was used for quantitative variables. Logistic regression model was performed in order to assess variables related to hearing recovery. Results: The incidence of abnormal VEMP responses was found in 43 per cent of patients. A statistically significant relationship was reported between VEMP test findings and hearing recovery. 70% of patients with normal VEMP had hearing recovery. 60% of patients with complete recovery showed normal VEMP. No patient with complete or moderate recovery had absent VEMP. Furthermore, patients without dizziness had normal or lower amplitude VEMP response. Patients with vertigo had absent VEMP. Discussion: A statistically significant relationship between hearing recovery and VEMP was found coinciding with other authors (Iwasaki, Wang, Korres). Normal or lower amplitude VEMP responses are not indicative of hearing recovery. However, absent or unreadable VEMP responses are a sign of poor prognosis and worse hearing recovery. In addition, according to some authors (Stamatiou, Iwasaki), the presence of vestibular disorders in sudden sensorineural hearing loss appears to correlate better with saccular involvement than with an isolated dysfunction of the semicircular canals. Conclusion: VEMP testing could be useful to detect vestibular involvement, even in the absence of vertigo. Moreover, VEMP testing could predict a greater extent of damage, which could be associated to a poorer hearing recovery in patients with sudden sensorineural hearing loss.

Submitted by Renata Lopes (renatasil82@gmail.com) on 2016-05-06T12:12:14Z No. of bitstreams: 1 emersondeoliveiramuniz.pdf: 8307586 bytes, checksum: 606af644defaa4b8c7ac04fed4b1bcbd (MD5) / Approved for entry into archive by Adriana Oliveira (adriana.oliveira@ufjf.edu.br) on 2016-06-07T15:51:16Z (GMT) No. of bitstreams: 1 emersondeoliveiramuniz.pdf: 8307586 bytes, checksum: 606af644defaa4b8c7ac04fed4b1bcbd (MD5) / Made available in DSpace on 2016-06-07T15:51:16Z (GMT). No. of bitstreams: 1 emersondeoliveiramuniz.pdf: 8307586 bytes, checksum: 606af644defaa4b8c7ac04fed4b1bcbd (MD5) Previous issue date: 2013-10-31 / CAPES - Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / Numa contemporaneidade na qual as estatísticas apontam o incremento dos chamados desastres naturais em todo o mundo, sobretudo em nações como o Brasil, onde o crescente adensamento populacional nas cidades faz delas as áreas preferenciais para a realização das catástrofes, especialmente quando marcadas pela desigualdade social e pela baixa capacidade institucional de prevenção e gerenciamento desses fenômenos. A presente pesquisa faz uma interpretação geográfica do evento de inundação brusca ocorrido na cidade de Areal – RJ no dia 12 de janeiro de 2011, diretamente vinculado à catástrofe socioambiental que se processou na Região Serrana do estado naquela data. A partir da experiência vivenciada pelo próprio autor como testemunha e vítima do desastre em Areal, o trabalho registra como o evento se processou no tempo e no espaço e discute numa proposta integradora as condicionantes físicas e socioinstitucionais relacionadas ao fato da cidade ter tido a quase totalidade de sua área urbana fortemente impactada pela inundação. Dentre as condicionantes analisadas ressalta-se a presença e a operação da barragem Morro Grande, um reservatório para aproveitamento hidrelétrico a montante e próximo da área urbana do município. Duas paisagens são consideradas na interpretação, a da bacia hidrográfica do rio Piabanha e a da área urbana do município de Areal, cidade localizada no curso médio do rio que dá nome à bacia. As interações natureza-sociedade na geração do desastre, o mapeamento da área urbana afetada no evento de 2011, a análise da capacidade político-institucional de resposta à crise e o ordenamento urbano de Areal no engendramento de riscos são aspectos averiguados na pesquisa. Com base na proposta de Libaut (1971), a metodologia obedeceu quatro etapas seqüenciadas e empregou técnicas de trabalho de campo, entrevistas e mapeamento da área inundada. A pesquisa conclui que o evento na cidade foi de grande porte, deflagrado por um contexto de exceção na dinâmica flúvio-meteorológica regional, mas amplificado por fatores ligados à própria espacialidade local. / At the present times, the statistics are aiming to the increase of those called “global nature disasters”, particularly in nations like Brazil where the population of small and big cities are in constant development which contribute in addition to, the weakness of the administration and management of the prevention of disasters like the one that occurred at the city of Areal- RJ on January 12, 2011. The present work made a geographical interpretation of that event that might be the cause for that sudden flood that covered the city, located near at the highlands region of Rio de Janeiro. From that self-experience as a witness and victim the author, present a friendly proposition to discuss the construction and operation of the Morro Grande, located near that urban area and used as a Hydroelectric Reservoir to the enhancement of the region. At this point there are multiple factors to be analyzed like the area between the rivers, the urban area, the interaction nature-society, description of the area affected, the capacity political-institutional to respond to these type of events. This work is in according with Libaut (1971), this work follow the four steps and technical of work on the field. Interviews and description of the area object of this work. The paper concludes that the event in the city was large, triggered by an exception in the context of river dynamics and regional weather, but amplified by factors related to spatiality own site.