Vestibular recruitment: new application for an old concept / Recrutamento vestibular: nova aplicação para um conceito antigo

Abstract Introduction Vestibular recruitment is a sign of hyperexcitability of central vestibular neurons and may be characteristic of peripheral vestibular damage. Objective To define the post-caloric recruitment index and its ability to predict the stage of vestibular compensation and peripheral lesion. Methods First of all, we demonstrated that larger values in the cold post-caloric stimulation compared to warm stimulation were equivalent to vestibular recruitment observed during the sinusoidal harmonic acceleration test. In the next step, patients with vestibular complaints and asymptomatic controls were submitted to the caloric test. We calculated post-caloric recruitment index for the control group. Among the study group, we analyzed the relation between post-caloric recruitment and unilateral weakness as well as the types of vestibular diagnoses. Results Mean post-caloric recruitment was 17.06% and 33.37% among the control and study group, respectively. The ratio between post-caloric recruitment and unilateral weakness was 1.3 in the study group. Among recruiting subjects, no significant difference of unilateral weakness from the lesioned or healthy side was observed. We found no differences in vestibular diagnoses between recruiting and non-recruiting subjects. Conclusion Post-caloric recruitment index identified asymmetric vestibular tonus and central compensation. The normal value was established at 17.06%.

Resumo Introdução O recrutamento vestibular é um sinal de hiperexcitabilidade dos neurônios vestibulares centrais e pode ser característico de lesão vestibular periférica. Objetivo Definir o índice de recrutamento pós‐calórico e sua capacidade de predizer o estágio de compensação vestibular e lesão periférica. Método Em primeiro lugar, demonstramos que valores maiores na estimulação pós‐calórica fria em relação à estimulação quente foram equivalentes ao recrutamento vestibular observado durante o teste de aceleração harmônica sinusoidal. Na etapa seguinte, os pacientes com queixas vestibulares e controles assintomáticos foram submetidos à prova calórica. Calculamos o índice de recrutamento pós calórico para o grupo controle. No grupo de estudo, analisamos a relação entre o recrutamento pós‐calórico e predomínio labiríntico, bem como os tipos de diagnósticos vestibulares. Resultados O recrutamento pós‐calórico médio foi de 17,06% e 33,37% nos grupos controle e estudo, respectivamente. A razão entre o recrutamento pós‐calórico e o predominício labiríntico foi de 1,3 no grupo de estudo. Nos sujeitos com recrutamento, não foi observada diferença significativa de predominício labiríntico do lado lesionado ou saudável. Não encontramos diferenças de diagnóstico vestibular entre sujeitos com recrutamento e sem recrutamento. Conclusão O índice de recrutamento pós‐calórico identificou tônus vestibular assimétrico e compensação central. O valor normal foi estabelecido em 17,06%.

P3 Cognitive Potential in Cochlear Implant Users

Abstract Introduction The P3 cognitive evoked potential is recorded when a subject correctly identifies, evaluates and processes two different auditory stimuli. Objective to evaluate the latency and amplitude of the P3 evoked potential in 26 cochlear implant users with post-lingual deafness with good or poor speech recognition scores as compared with normal hearing subjects matched for age and educational level. Methods In this prospective cohort study, auditory cortical responses were recorded from 26 post-lingual deaf adult cochlear implant users (19 with good and 7 with poor speech recognition scores) and 26 control subjects. Results There was a significant difference in the P3 latency between cochlear implant users with poor speech recognition scores (G-) and their control group (CG) (p= 0.04), and between G- and cochlear implant users with good speech discrimination (G+) (p= 0.01). We found no significant difference in the P3 latency between the CG and G+. In this study, all G- patients had deafness due to meningitis, which suggests that higher auditory function was impaired too. Conclusion Post-lingual deaf adult cochlear implant users in the G- group had prolonged P3 latencies as compared with the CG and the cochlear implant users in the G+ group. The amplitudes were similar between patients and controls. All G- subjects were deaf due to meningitis. These findings suggest that meningitis may have deleterious effects not only on the peripheral auditory system but on the central auditory processing as well.

Sensitivity of caloric test and video head impulse as screening test for chronic vestibular complaints

OBJECTIVE: This study compared the results of the caloric test with those of the video head impulse test obtained during the same session and evaluated whether the former can be used to screen for non-acute vestibular dysfunction. METHODS: A total of 157 participants complaining of dizziness with vestibular characteristics of varying durations and clinical courses completed the caloric test and video head impulse test. RESULTS: Significantly more caloric test results than video head impulse test results were abnormal. CONCLUSIONS: The results of the caloric test and video head impulse test are distinct but complement each other. Within our sample, the caloric test was more sensitive for vestibular dysfunction. Therefore, the video head impulse test is not a suitable screening tool of the vestibular system in patients with chronic complaints.

Hearing performance as a predictor of postural recovery in cochlear implant users / Desempenho auditivo como preditor de recuperação postural em usuários de implante coclear

Abstract Objective This study aimed to evaluate if hearing performance is a predictor of postural control in cochlear implant (CI) users at least six months after surgery. Methods Cross-sectional study including (CI) recipients with post-lingual deafness and controls who were divided into the following groups: nine CI users with good hearing performance (G+), five CI users with poor hearing performance (G−), and seven controls (CG). For each patient, computerized dynamic posturography (CDP) tests, a sensory organization test (SOT), and an adaptation test (ADT) were applied as dual task performance, with first test (FT) and re-test (RT) on the same day, including a 40–60 min interval between them to evaluate the short-term learning ability on postural recovery strategies. The results of the groups were compared. Results Comparing the dual task performance on CDP and the weighted average between all test conditions, the G+ group showed better performance on RT in SOT4, SOT5, SOT6, and CS, which was not observed for G− and CG. The G− group had significantly lower levels of short-term learning ability than the other two groups in SOT5 (p = 0.021), SOT6 (p = 0.025), and CS (p = 0.031). Conclusion The CI users with good hearing performance had a higher index of postural recovery when compared to CI users with poor hearing performance.

Resumo Objetivo O presente estudo teve por objetivo avaliar se o desempenho auditivo é preditor de controle postural em usuários de IC pelo menos seis meses após a cirurgia. Método Estudo transversal que consistiu em recipientes de implante coclear (IC) com surdez pós-lingual e controles, que foram divididos nos seguintes grupos: nove usuários de IC com bom desempenho auditivo (G+), cinco usuários de usuários de IC com desempenho auditivo insatisfatório (G-) e sete controles (GC). Aplicamos os testes de posturografia dinâmica computadorizada (PDC), de organização sensitiva (TOS) e de adaptação (TAd) como desempenho de dupla tarefa, primeiro teste (PT) e reteste (RT) no mesmo dia, com intervalo de 40-60 minutos entre testes, com o objetivo de avaliar a capacidade de aprendizado em curto prazo nas estratégias de recuperação postural. Comparamos os resultados dos testes. Resultados Na comparação do desempenho de dupla tarefa no teste PDC e a média ponderal entre todas as condições de teste, o grupo G+ demonstrou melhor desempenho no RT nos TOS4, TOS5, TOS6 e EC, o que não foi observado para os grupos G- e GC. O grupo G- obteve níveis significantemente mais baixos de capacidade de aprendizado em curto prazo vs. outros dois grupos no TOS5 (p = 0,021), TOS6 (p = 0,025) e EC (p = 0,031). Conclusão Usuários de IC com bom desempenho auditivo tiveram índice melhor de recuperação postural, quando comparados com usuários de IC com desempenho auditivo insatisfatório.

Dizziness profile and clinical features: a population based survey in São Paulo City, Brazil / Perfil e características clínicas de tontura: um estudo baseado na população da cidade de São Paulo

OBJECTIVE: This is a cross-sectional epidemiological survey designed to estimate the prevalence of dizziness among the adult population of the city of São Paulo, Brazil, and to describe the clinical features and level of discomfort. METHOD: This population based study was conductedin the city of São Paulo, Brazil, between April and October 2012. A total of 1,960 household interviews were completed. The following variables were assessed: gender, age, clinical characteristics of dizziness, and dizziness disability index. Chi-square test, Student's t-test,Tukey test and logistic regression were used for statistical analysis. RESULTS: The dizziness prevalence in São Paulo was 42%. Peaks of dizziness were observed in two age groups: 49% among the 46 to 55 year-old, and 44% among the elderly subjects(> 65 years-old). Vestibular vertigo was detected in 8.3% of patients, with a strong female preponderance (p < 0.001). Symptoms caused disability in 27% of the affected respondents and were more frequent among women (p < 0.001). These sought medical care more frequently (p < 0.001). The dizziness disability index was significantly higher (p = 0.0165) among subjects with a lower educational level. There was no correlation between dizziness discomfort and the type of job. CONCLUSION: The prevalence of dizziness in São Paulo, Brazil, was established at 42%. Among the symptomatic subjects, 67% reported interruption of daily activities, but only 46% of them sought medical attention.

RESUMO OBJETIVO: Estudo epidemiológico transversal, desenvolvido para avaliar a prevalência de tontura entre a população adulta da cidade de São Paulo, Brasil, e descrever as características clínicas e nível de desconforto. MÉTODO: Estudo de base populacional na cidade de São Paulo, Brasil, entre abril e outubro de 2012. Um total de 1.960 entrevistas domiciliares foram concluídas. As seguintes variáveis foram analisadas: sexo, idade, características clínicas de tonturas e vertigens, índice de incapacidade. Os testes qui-quadrado, "t" de Student, Tukey e regressão logística foram utilizados para análise estatística. RESULTADOS: Aprevalência de tontura em São Paulo foi de 42%. Em dois grupos etários, foram observados picos de tontura: 49% entre os 46 e 55 anos de idade e 44% entre os idosos (> 65 anos de idade). Vertigem vestibular foi detectada em 8,3%, com uma forte preponderância para o sexo feminino (p <0,001). Os sintomas causaram deficiência em 27% dos entrevistados, com predominância entre as mulheres (p <0,001), que procuraram atendimento médico commais freqüência (p <0,001). O índice de incapacidade por tontura foi significativamente maior (p = 0,0165) entre os indivíduos com menor escolaridade. Não houve correlação entre desconforto por tontura e o tipo de emprego. CONCLUSÃO: Aprevalência de tontura em São Paulo, Brasil, foi estabelecida em 42%. Entre os pacientes sintomáticos, 67% relataram a interrupção das atividades diárias, mas apenas 46% deles procuraram atendimento médico.

Estudo comparativo entre audiometria tonal limiar e resposta auditiva de estado estavel em normouvintes / Comparative study between pure tone audiometry and auditory steady-state responses in normal hearing subjects

Introdução: As respostas auditivas de estado estável permitem avaliar de forma objetiva limiares auditivos frequência-específica. A audiometria tonal é o exame padrão-ouro; no entanto, nem sempre pode ser conclusiva, principalmente em crianças e adultos não colaborativos. Objetivo: Comparar os limiares auditivos da RAEE aos da audiometria tonal em indivíduos com audição normal. Materiais e métodos: Foram incluídos neste estudo prospectivo de corte transversal 26 adultos (52 orelhas), de ambos os gêneros, com audiometria normal e sem queixas otológicas. Os pacientes foram submetidos a anamnese, otomicroscopia, audiometria e imitanciometria. A seguir, realizou-se avaliação de respostas auditivas de estado estável. Os resultados obtidos foram analisados estatisticamente e comparados entre si. Resultados: A diferença entre os limiares (em dB NA) obtidos em ambos os exames para cada frequência testada foi de 7,12 dB para 500 Hz; 7,6 dB para 1000 Hz; 8,27 dB para 2000 Hz e 9,71 dB para 4000 Hz, com limiares mais elevados na RAEE, em todas as frequências. Não houve diferença estatística entre as médias para cada frequência testada. Conclusão: Os limiares obtidos na RAEE foram comparáveis aos da audiometria tonal em indivíduos normouvintes; entretanto, não deve ser usado como único método de avaliação auditiva. .

Introduction: Auditory steady-state responses (ASSR) are an important tool to detect objectively frequency-specific hearing thresholds. Pure-tone audiometry is the gold-standard for hearing evaluation, although sometimes it may be inconclusive, especially in children and uncooperative adults. Aim: Compare pure tone thresholds (PT) with ASSR thresholds in normal hearing subjects. Materials and methods: In this prospective cross-sectional study we included 26 adults (n = 52 ears) of both genders, without any hearing complaints or otologic diseases and normal puretone thresholds. All subjects had clinical history, otomicroscopy, audiometry and immitance measurements. This evaluation was followed by the ASSR test. The mean pure-tone and ASSR thresholds for each frequency were calculated. Results: The mean difference between PTand ASSR thresholdswas 7,12 for 500 Hz, 7,6 for 1000 Hz, 8,27 for 2000 Hz and 9,71 dB for 4000 Hz. There were no difference between PT and ASSR means at either frequency. Conclusion: ASSR thresholds were comparable to pure-tone thresholds in normal hearing adults. Nevertheless it should not be used as the only method of hearing evaluation. .

Contribution of audiovestibular tests to the topographic diagnosis of sudden deafness

Sudden hearing loss (SHL) is an ENT emergency defined as sensorineural hearing loss (SNHL) > 30 dB HL affecting at least 3 consecutive tonal frequencies, showing a sudden onset, and occurring within 3 days. In cases of SHL, a detailed investigation should be performed in order to determine the etiology and provide the best treatment. Otoacoustic emission (OAE) analysis, electronystagmography (ENG), bithermal caloric test (BCT), and vestibular evoked myogenic potential (VEMP) assessments may be used in addition to a number of auxiliary methods to determine the topographic diagnosis. OBJECTIVE: To evaluate the contribution of OAE analysis, BCT, VEMP assessment, and magnetic resonance imaging (MRI) to the topographic diagnosis of SHL. METHOD: Cross-sectional and retrospective studies of 21 patients with SHL, as defined above, were performed. The patients underwent the following exams: audiometry, tympanometry, OAE analysis, BCT, VEMP assessment, and MRI. Sex, affected side, degree of hearing loss, and cochleovestibular test results were described and correlated with MRI findings. Student's t-test was used for analysis of qualitative variables (p < 0.05). RESULTS: The mean age of the 21 patients assessed was 52.5 ± 15.3 years; 13 (61.9%) were women and 8 (38.1%) were men. Most (55%) had severe hearing loss. MRI changes were found in 20% of the cases. When the audiovestibular test results were added to the MRI findings, the topographic SHL diagnosis rate increased from 20% to 45%. CONCLUSION: Only combined analysis via several examinations provides a precise topographic diagnosis. Isolated data do not provide sufficient evidence to establish the extent of involvement and, hence, a possible etiology...

Diagnostico precoce da deficiencia auditiva no primeiro ano de vida de criancas com alto risco atraves de audiometria de tronco cerebral / Early diagnosis of hearing loss in high-risk infants using auditory brainstem respons

O ouvido e um orgao fundamental na comunicacao humana. Uma deficiencia auditiva nao corrigida precocemente gera alteracoes irreversiveis, comprometendo de maneira global o processo de aprendizado...

Formas incomuns de apresentaçäo clínica da hiperplasia do tecido linfóide da rinofaringe / Uncommon forms of clinical presentation of nasopharyngeal hyperplastic lymphoid tissue

Os autores apresentam 2 casos de hiperplasia do tecido linfóide da rinofaringe, com aspectos clínicos e radiológicos incomuns. Säo discutidos os principais aspectos clínicos e radiológicos no diagnóstico diferencial entre hiperplasia linfóide e neoplasias