Outcomes of Automated Auditory Evoked Potential Performed in Different Settings and the Factors Associated with Referred Cases

Abstract Introduction For the population with risk factors for hearing loss, the first option to assess the hearing status is the performance of the automated brainstem auditory evoked potential (BAEP) test because of its efficacy in identifying retrocochlear hearing loss. Objective To verify the outcomes of automated BAEP performed in different settings as well as the factors associated with the prevalence of hearing impairment. Methods Cross-sectional study conducted from October of 2014 to May of 2015. The sample consisted of 161 infants with at least one risk factor for hearing loss who underwent automated BAEP during the hospital stay or at the outpatient clinic. After 30 days, the altered cases were referred for BAEP diagnosis. Results One hundred and thirty-eight infants (86%) had a result of "pass" and 23 (14%) of "failure" in the automated BAEP. There was no statistically significant difference in the rate of "referred" results between examinations performed in different settings. The infants' ages did not influence the number of abnormal cases. All of the 23 infants who presented a "referred" result in the automated BAEP, unilateral or bilateral, were sent for BAEP diagnosis, and out of these, 9 (39%) remained with at least some degree of alteration. The average age of diagnosis was 2.7 months. Conclusion The results of the automated BAEP were similar when performed during hospitalization or after discharge. Neither the age at the examination nor the gender of the patient influenced the prevalence of hearing loss.

Variables in P300 recording: task type and electrode position

ABSTRACT Purpose To analyze the latency and amplitude of P300 responses obtained with electrodes positioned at Cz and Fz and in different tasks of infrequent stimulus identification in normal hearing individuals. Methods Forty adults of both genders participated in the study. Three recordings with three different tasks were obtained for the identification of the infrequent stimulus; simultaneous recordings were obtained from Cz and Fz positions. Results Cz position showed significantly greater amplitudes and lower latencies than Fz. Regarding the three tasks, only “pronouncing the word ’thin’” was different from “raising a finger”, with lowest latencies for the verbal task. Regarding amplitude, significantly higher values were observed for “raising a finger”, followed by “pronouncing the word ‘thin’” and mental counting. Conclusion Cz obtained the best values, highest amplitude and lowest latency. Lowest latencies were obtained for the task of “pronouncing the word ‘thin’” and the highest amplitudes were obtained for “raising a finger”.

Open fitting: performance verification of receiver in the ear and receiver in the aid / Adaptação aberta: verificação do desempenho RITE e RITA

OBJECTIVE: To verify the receiver in the ear and receiver in the aid adaptations by measuring in situ the speech perception and users' level of satisfaction. METHODS: The study was approved by the research ethics committee (Process: 027/2011). Twenty subjects older than 18 years with audiological diagnosis of mild and moderate bilateral descending sensorineural hearing loss were evaluated. The subjects were divided into two groups, where G1 (group 1) was fitted with open-fit hearing aids with the built-in receiver unit (receiver in the ear) and G2 (group 2) was fitted with open-fit hearing aids with RITE. A probe microphone measurement was performed to check the gain and output provided by the amplification and for assessment of speech perception with Hearing in Noise Test with and without hearing aids. After a period of six weeks of use without interruption, the subjects returned for follow-up and answered the Satisfaction with Amplification in Daily Life questionnaire, and were again subjected to Hearing in Noise Test. RESULTS: Both groups presented better test results for speech recognition in the presence of noise. CONCLUSION: Groups 1 and 2 were satisfied with the use of hearing aids and improved speech recognition in silent and noisy situations with hearing aids. .

OBJETIVO: Estudo clínico prospectivo para verificar as adaptações RITE e RITA por meio da mensuração in situ da percepção da fala e satisfação dos usuários. MÉTODO: Estudo aprovado pelo CEP (Processo no 027/2011). Foram avaliados 20 indivíduos maiores de 18 anos com diagnóstico audiológico de perda auditiva sensorioneural descendente bilateral de graus leve e moderado. Os indivíduos foram divididos em dois grupos, onde o G1 (grupo 1) foi adaptado com AASI open-fit com receptor no próprio aparelho (RITA) e o G2 (grupo 2) foi adaptado com AASI open-fit com receptor no canal (RITE). Foi realizada a medida com microfone-sonda para verificação do ganho e saída do AASI e avaliação da percepção da fala com Hearing in Noise Test (HINT), sem e com AASI. Após um período de seis semanas de uso sem interrupções, o individuo retornou para acompanhamento e respondeu ao questionário SADL (Satisfaction with Amplification in Daily Life Scale) e realizou o HINT. RESULTADOS: Os grupos apresentaram melhores resultados no teste de reconhecimento da fala com presença de ruído. CONCLUSÃO: Os grupos 1 e 2 apresentaram satisfação com o uso do AASI e melhora no reconhecimento de fala nas situações de silêncio e ruído com o uso de AASI. .

Protocolo para captação dos potenciais evocados auditivos de longa latência / Protocol to collect late latency auditory evoked potentials

Os potenciais evocados auditivos de longa latência (PEALLs) se referem a uma série de mudanças elétricas, ocorridas no sistema nervoso central, resultante da estimulação da via sensorial auditiva. Muitos estudos abordam o uso destes potenciais, controlando o artefato gerado pelo movimento ocular com a utilização de equipamentos com grande número de canais. Porém, na prática clínica nacional, a realidade é diferente, havendo disponibilidade de equipamentos com número reduzido de canais. Objetivo: Comparar dois métodos de controle do artefato gerado pelo movimento ocular durante a captação dos PEALLs usando dois canais de registro. Material e método: Estudo prospectivo pela aplicação de dois métodos de captação dos PEALLs (subtração do artefato ocular e controle do limite de rejeição) em 10 adultos ouvintes normais. Resultados: Não foi observada diferença estatisticamente significante entre os valores de latência obtidos com o uso dos dois métodos, apenas entre os valores de amplitude. Conclusão: Os dois métodos foram eficientes para a captação dos PEALLs e para o controle do artefato do movimento ocular. O método do controle do limite de rejeição promoveu maiores valores de amplitude.

Long Latency Auditory Evoked Potentials (LLAEP) represents a number of electrical changes occurring in the central nervous system, resulting from stimulation of the auditory sensorial pathways. Many studies approach the use of these potentials controlling the artifact created by eye movement with the use of equipment with a large number of channels. However, what happens is very different in Brazilian clinical practice, where the equipment used has a very limited number of channels. AIM: to compare the two methods used to control the artifacts created by eye movements during LLAEP capture using two recording channels. Materials and methods: this is a prospective study with the application of two LLAEP capturing methods (eye artifact subtraction and rejection limit control) in 10 normal hearing individuals. Results: we did not observe statistically significant differences concerning the latency values obtained with the use of both methods, only concerning amplitude values. Conclusion: both methods were efficient to capture the LLAEP and to control the eye movement artifact. The rejection limit control method produced greater amplitude values.

The development and clinical application of acoustical technique in hip joint / 华中科技大学学报（医学）（英德文版）

A non-invasive acoustical system was developed for the measurement of transmission properties of acoustic waves in the hip joints. The instrumentation consisted of three sub-systems. An excitation system employed a vibratory force at the sacrum of the test subjects. A transduction system included a pair of identical microphones installed in the tubes of two stethoscopes, which were placed at the greater trochanters on both sides for picking up the acoustical signals transmitted across the hip joints. The data acquisition and analysis system was a portable signal analyzer with a program of dual channel digital filter for measuring the power of acoustical signal in 1/3-octave frequency bands. 27 normal adults, 20 normal pre-school children and 40 normal neonates were randomly selected for testing. Coherence function (CF) and discrepancy (D) was measured during the testing. Results from the three groups showed that there was a high coherence of the signals (CF > 0.9) and a small discrepancy (D 0.93) and a smaller discrepancy (D < 2 dB) was observed. This study showed that the development of the acoustical technique provided a practical method with objective parameters. The results obtained in this study can offer a baseline for further investigation of hip disorders particularly those related to structural abnormalities of the hip.

Monitorização do plano anestésico por técnicas estatísticas no domínio da freqüência / Monitoring depth of anaesthesia by frequency-domain statistical techniques

O potencial evocado auditivo de média latência (MLAEP) tem sido empregado na avaliação do nível anestésico, sendo usual a análise morfológica (AEPidx - Indice de Potencial Evocado Auditivo, e DT - Distância Taxonômica). Neste trabalho, técnicas de detecção objetiva de respostas no domínio da freqüência (MSC - Magnitude Quadrada da Coerência, e CSM - Medida de Sincronismo de Componentes) foram avaliadas a partir de EEG sob estimulação auditiva. Dez voluntários foram estimulados com cliques repetitivos (7,645 Hz, nível de pressão sonora de 75 dB SPL), sendo EEG adquirido na derivação Vértex - Lobo Auricular durante 10 min sem administração de anestésico e dois períodos consecutivos de infusão contínua de propofol (3 mg/Kg/h, sedação, e 9 mg/Kg/h, anestesia) de 45 min cada. O instante de perda de consciência foi estimado com base no pressionamento de uma maniqueta em resposta a estímulos luminosos a cada 15 s. MSC e CSM permitem a inferência estatística de ausência de resposta auditiva (valor crítico, para e.g. alfa = 1 por cento) ao longo do processo anestésico. Além disso, MSC(Ÿ) e CSM(Ÿ) se reduzem durante a infusão (mais expressivamente na anestesia), tendo maior concordância (diagramas de Bland-Altman) com os resultados da maniqueta que AEPidx e DT, e maior equivalência (Wilcoxon Signed-Rank Test, alfa = 5 por cento) que DT.

Potenciales evocados auditivos del tallo cerebral / Evoked potentials auditory of cerebral stem

Presentamos el análisis de las curvas de intensidad-latencia de 20 sujetos normales en edades comprendidas entre 15-35 años. La estimulación acústica se efectúo con clicks, usando un equipo marca Amplaid, modelo MK-10, presentados monoauralmente a través de audífonos, pasando 2000 clicks a una tasa de 11/seg. Se considera de gran importancia establecer las curvas de intensidad/latencia en población normal para poder comparar con registros patológicos

High frequency resonant oscillations technique to improve nasal muco-ciliary transport.

A modified high frequency resonant oscillations (HFRO) technique was developed to improve the nasal muco-ciliary transport in patients with impaired ciliary functions due to various chronic diseases of the upper respiratory tract. Twelve healthy males (group I) and ten patients suffering from malignancy of the upper respiratory tract (group II) were exposed to HFRO in order of 200, 250, 300, 400, 500 Hz respectively. The muco-ciliary transport (MCT) was assessed by using saccharine clearance time technique. A significant improvement in MCT was observed in both the groups at all the frequency levels, more so in the range of 400 and 500 Hz. An overall relative improvement of 174 per cent (P less than 0.01) in group I and 145 per cent (P less than 0.001) in group II was observed. No significant side effects were noted.