Visual evoked potential abnormalities in patients with COVID-19

SUMMARY OBJECTIVE: It has been suggested that diseases that may cause visual evoked potential abnormality, such as optic neuritis, may be associated with the coronavirus disease 2019. This study aimed to find out whether there are visual evoked potential abnormalities in coronavirus disease 2019 patients using pattern reversal visual evoked potential and flash visual evoked potential. METHODS: Patients with a history of coronavirus disease 2019 (coronavirus disease 2019 patients) and controls were included in this prospective case-control study. This study was conducted in the Clinical Neurophysiology Laboratory of Adana City Training and Research Hospital. Individuals without visual impairment were included. Coronavirus disease 2019 patients were required to have clinical features consistent with previous acute infection and a positive nose swab polymerase chain reaction test. Visual evoked potential was applied to coronavirus disease 2019 patients between July 2020 and July 2021. Controls consisted of patients without a history of chronic disease who underwent a visual evoked potential study between June 2017 and June 2018 due to headache or dizziness. Pattern reversal visual evoked potential and flash visual evoked potential were applied to all participants. N75, P100, and N135 waves obtained from pattern reversal visual evoked potential and P1, N1, P2, N2, P3, and N3 waves obtained from flash visual evoked potential were analyzed. RESULTS: A total of 44 coronavirus disease 2019 patients and 40 controls were included in the study. Age and gender were not different between the two groups. Pattern reversal visual evoked potential parameters were not different between the two groups. Right P2 latency was 114.4±21.1 and 105.5±14.7 ms in coronavirus disease 2019 patients and controls, respectively (p=0.031). Patients with P100 and P2 wave abnormalities were 6 (13.6%) and 13 (29.6%), respectively. CONCLUSION: This study showed that there may be visual evoked potential abnormalities in coronavirus disease 2019 patients.

Utilização do Potencial Auditivo de Estado Estável em lactentes com baixo risco para perda auditiva / Use of Auditory Steady State Response in infants at low risk for hearing loss / Uso del potencial auditivo de estado estacionario en bebés con bajo riesgo de pérdida auditiva

Introdução: Com base na necessidade do diagnóstico audiológico e da intervenção precoce na vida de uma criança com perda auditiva, faz-se necessário a elaboração de protocolos de avaliação auditiva que forneçam o maior número de informações. Objetivo: Analisar um programa de saúde auditiva infantil com relação à adesão à triagem auditiva e procedimentos de diagnóstico. Metodologia: Pesquisa de caráter transversal com análise quantitativa. Realizado em três etapas: 1ª etapa: triagem auditiva de neonatos de alojamento conjunto; 2ª etapa: reteste das falhas; 3ª etapa: diagnóstico audiológico dos lactentes que falharam nas etapas anteriores com a utilização do Potencial Evocado Auditivo de Estado Estável (PEAEE) em conjunto com o Potencial Evocado Auditivo de Tronco Encefálico (PEATE). Resultados: Em 2019, 1.898 neonatos foram triados e destes, 287 (15.2%) falharam na primeira testagem em pelo menos uma orelha. Um total de 197 (10.3%) foram retestados e 14 (0,73%) falharam em pelo menos uma orelha. Dez (0,52%) neonatos retornaram para diagnóstico compondo uma amostra homogênea de neonatos nascidos a termo. Um neonato apresentou perda auditiva unilateral. O tempo necessário para coleta de dados no PEAEE foi de 20 minutos. Conclusão: O PEAEE pode ser considerado uma alternativa a ser utilizado na bateria de testes na avaliação audiológica infantil, juntamente com outros procedimentos, utilizando-se do princípio de verificação cruzada e adicionando uma informação valiosa, especialmente com relação às baixas frequências. (AU)

Introduction: Based on the need for audiological diagnosis and intervention as soon as possible in the life of a child with hearing loss, it is necessary to elaborate of hearing evaluation protocols with high efficiency, which provide the greatest amount of information. Aim: To analyze a pediatric hearing health program regarding their adherence to hearing screening, failure rates, and diagnostic procedures. Method: This is a cross-sectional, descriptive, quantitative study, and consisted of tree stages: Performed in three steps: 1st step: hearing screening of rooming-in neonates; 2nd stage: retest of failures; 3rd stage: audiological diagnosis of infants who failed in the previous stages using the Steady State Response (ASSR) together with the Brainstem Evoked Response Audiometry (BERA). Results: In 2019, 1,898 infants were submitted to the program, of whom 287 (15.2%) failed the screening in at least one of the ears. A total of 197 (10.3%) infants attended the retest and 14 (0.73%) failed the TOAE in at least one of the ears. Ten (0.52%) infants returned for diagnosis. The sample was homogeneously full-term children. One child showed unilateral HL. The average amount of time required to collect information in the ASSR was 20 minutes. Conclusion: For diagnosis, ASSR can be an alternative to be used in the battery of examinations in pediatric hearing assessment along with the other procedures, using the cross-check principle and adding valuable information, especially regarding the low frequencies. (AU)

Introducción: En base a la necesidad de diagnóstico audiológico e intervención lo antes posibles en la vida de un niño con pérdida auditiva, es necesario elaborar protocolos de evaluación auditiva de alta eficiencia, que proporcionan la mayor cantidad de información. Objetivo: Analizar un programa de salud auditiva infantil en cuanto a la adherencia al tamizaje auditivo, tasa de fracaso y procedimientos diagnósticos. Metodología: Investigación transversal con análisis cuantitativo, Realizado en tres pasos: 1er paso: tamizaje auditivo de los neonatos en alojamiento conjunto; 2ª etapa: retest de fallas; 3ª etapa: diagnóstico audiológico de los lactantes que fracasaron en las etapas anteriores utilizando el Potencial Evocado Auditivo de Estado Estacionario junto con el Potencial Evocado Auditivo de Tallo Cerebral. Resultados: Em 2019, se cribaron 1,898 neonatos y de estos, 287 (15,2%) no pasaron la primera prueba en al menos un oído. Un total de 197 (10,3) fueron reevaluados y 14 (0,73%) fallaron en al menos un oído. Diez (0,52%) neonatos regresaron para diagnóstico, conformando una muestra homogénea de neonatos a término, con una edad gestacional media de 39 semanas y dos días. Un neonato tuvo pérdida auditiva unilateral. El tiempo de recogida de los resultados en el ASSR fue de 20 min. Conclusión: Para el diagnóstico, la ASSR puede considerarse una alternativa para ser utilizada en la batería de pruebas en la evaluación audiológica infantil, junto con otros procedimientos, utilizando el principio de verificación cruzada y agregando información valiosa, especialmente en lo que se refiere a las bajas frecuencia. (AU)

Potenciales evocados auditivos de tronco en neonatos nacidos a gran altitud / Brainstem auditory evoked potentials in newborn infants born in a high-altitude area

Introducción. Una forma no invasiva y segura de evaluar los parámetros neurofisiológicos en recién nacidos es la evaluación de los potenciales evocados auditivos del tronco encefálico (PEAT). Objetivo. Evaluar las latencias e intervalos de ondas de los PEAT en neonatos sanos nacidos a gran altitud (Cusco, 3399 msnm). Población y métodos. Estudio transversal y prospectivo. Se incluyeron neonatos menores a 14 días de vida, dados de alta a menos de 7 días de nacidos, evaluados para determinar los valores de los PEAT a intensidades sonoras de 70 dB, 80 dB y 90 dB. Se incluyeron las variables edad gestacional, peso al nacer, tipo de parto. Se calcularon las diferencias de las medianas de las latencias e intervalos de las ondas según edad gestacional y peso al nacer. Resultados. Se evaluaron 96 neonatos (17 pretérminos). Las medianas de las latencias de las ondas I a V a 90 dB fueron las siguientes: onda I 1,56 ms; onda II 2,74 ms; onda III 4,37 ms; onda IV 5,62 ms, onda V 6,63 ms. La latencia de la onda I para 80 dB fue de 1,71 ms y para 70 dB de 1,88 ms. Los intervalos para las ondas (I-III), (III-V) y (I-V) fueron de 2,8 ms, 2,2 ms y 5,0 ms respectivamente, sin diferencias entre intensidades (p >0,05). La prematuridad y el bajo peso estuvieron asociados a latencias de la onda I más prolongadas (p <0,05). Conclusiones. Se presentan valores ajustados de latencias e intervalos de los PEAT en neonatos nacidos a gran altitud. Se identificó que, a distintas intensidades sonoras, se ven diferencias en las latencias de las ondas, pero no en los intervalos entre ondas.

Introduction. A non-invasive and safe way to assess neurophysiological parameters in newborn infants is the evaluation of brainstem auditory evoked potentials (BAEPs). Objective. To assess the latencies and wave intervals of BAEPs in healthy newborn infants born in a high-altitude area (Cusco, 3399 MASL). Population and methods. Cross-sectional and prospective study. Newborn infants younger than 14 days of age, discharged less than 7 days after birth, were assessed to determine BAEP values at intensities of 70 dB, 80 dB, and 90 dB. The study variables were gestational age, birth weight, and type of delivery. The median differences in wave latencies and intervals were estimated according to gestational age and birth weight. Results. A total of 96 newborn infants (17 preterm infants) were assessed. The median latencies of waves I­V at 90 dB were for wave I: 1.56 ms, wave II: 2,74 ms, wave III: 4.37 ms, wave IV: 5.62 ms, and wave V: 6.63 ms. The latency of wave I for 80 dB was 1.71 ms and for 70 dB, 1.88 ms. Wave intervals (I­III, III­V, I­V) were 2.8 ms, 2.2 ms, and 5.0 ms, respectively, without differences among intensities (p > 0.05). Prematurity and low birth weight were associated with a longer wave I latency (p < 0.05). Conclusions. Here we describe adjusted BAEP latency and interval values for newborn infants born at high altitude. At different sound intensities, we identified differences in wave latencies, but not in interwave intervals.

The P300 Auditory Evoked Potential in Cochlear Implant Users: A Scoping Review

Abstract Introduction The P300 auditory evoked potential is a long-latency cortical potential evoked with auditory stimulation, which provides information on neural mechanisms underlying the central auditory processing. Objectives To identify and gather scientific evidence regarding the P300 in adult cochlear implant (CI) users. Data Synthesis A total of 87 articles, 20 of which were selected for this study, were identified and exported to the Rayyan search software. Those 20 articles did not propose a homogeneous methodology, which made comparison more difficult. Most articles (60%) in this review compare CI users with typical hearing people, showing prolonged P300 latency in CI users. Among the studies, 35% show that CI users present a smaller P300 amplitude. Another variable is the influence of the kind of stimulus used to elicit P300, which was prolonged in 30% of the studies that used pure tone stimuli, 10% of the studies that used pure tone and speech stimuli, and 60% of the studies that used speech stimuli. Conclusion This review has contributed with evidence that shows the importance of applying a controlled P300 protocol to diagnose and monitor CI users. Regardless of the stimuli used to elicit P300, we noticed a pattern in the increase in latency and decrease in amplitude in CI users. The user's experience with the CI speech processor over time and the speech test results seem to be related to the P300 latency and amplitude measurements.

Asymmetry of Occupational Noise Induced Hearing Loss: An Electrophysiological Approach

Abstract Introduction The question as to whether occupational noise exposure causes symmetrical or asymmetrical hearing loss is still controversial and incompletely understood. Objective Two electrophysiological methods (cortical evoked response audiometry: CERA and auditory steady state responses: ASSR) were used to address this issue. Method 156 subjects with a well-documented history of noise exposure, a wide range of noise induced hearing loss (NIHL) and without middle ear pathology underwent both a CERA and an ASSR examination in the context of an exhaustive medicolegal expert assessment intended for possible compensation. Results Whatever the method (CERA or ASSR), the average electrophysiological hearing thresholds (1-2-3 kHz) are significantly worse in the left ear. The right - left differences in CERA and ASSR thresholds are strongly correlated with each other. No significant effect of frequency is found. No correlation is observed between right - left differences in hearing thresholds and either age or degree of hearing loss. Conclusion In NIHL, there is an actual average right - left difference of about 2.23 dB, i.e., 3.2%, the left ear being more impaired.

The contribution of concentric electrode-evoked potentials and nociceptive withdrawal reflex to the routine neurophysiological assessment of neuropathic pain: cross-sectional study / A contribuição dos potenciais evocados por eletrodo concêntrico e reflexo de retirada nociceptiva para a avaliação neurofisiológica de rotina da dor neuropática: estudo observacional transversal

ABSTRACT BACKGROUND AND OBJECTIVES: Conventional electrodiagnostic studies (EDX) are frequently used to support the diagnosis of peripheral neuropathic pain. However, routine EDX has poor diagnostic yield for identifying small fiber neuropathy, which may be cause of neuropathic pain in some patients. This study aimed to assess the gain in diagnostic yield brought by adding pain-related evoked potentials with concentric electrode (CN-PREP) and nociceptive withdrawal reflex (NWR) assessments to EDX. METHODS: Transversal observational accuracy study which included patients referred to routine EDX in a tertiary-care hospital who reported chronic neuropathic pain in their lower limbs. Besides routine EDX, subjects underwent CN-PREP and NWR assessments. Diagnostic yield and tolerability were examined and compared between test studies. RESULTS: The study enrolled 100 patients (54% female), with 57 ± 12 years. EDX was altered in 47% of all patients. The addition of CN-PREP alone, and NWR combined with CN-PREP increased diagnostic yield to 69% and 72%, respectively. CN-PREP proved to be well tolerable, while NWR was associated with higher test-related pain intensity and discontinuation rate (9% vs. 0%). Considering EDX as the reference test, CN-PREP sensitivity was 85.1% and specificity 58.5%. CONCLUSION: Combining CN-PREP with the routine EDX for patients with neuropathic pain is feasible and results in increased diagnostic yield. Conversely, the addition of NWR to the aforementioned tests provides little improvement to this yield and is less tolerable to the patient. Further studies are needed to determine the actual sensitivity and specificity of CN-PREP when compared to the gold-standard for small fiber neuropathy diagnosis, i.e. intraepidermal nerve fiber density assessment.

RESUMO JUSTIFICATIVA E OBJETIVOS: Estudos convencionais de eletrodiagnóstico (EDX) são frequentemente usados para apoiar o diagnóstico de dor neuropática periférica. No entanto, o EDX de rotina tem baixo rendimento diagnóstico para identificar neuropatia de pequenas fibras. O objetivo deste estudo foi avaliar o ganho no rendimento diagnóstico pela adição de avaliações de potenciais evocados relacionados à dor com eletrodo concêntrico (CN-PREP) e reflexo de retirada nociceptiva (NWR) ao EDX. MÉTODOS: Estudo de precisão observacional transversal que incluiu pacientes encaminhados para EDX de rotina com dor neuropática crônica em membros inferiores. Além do EDX de rotina, os indivíduos foram submetidos às avaliações CN-PREP e NWR. O rendimento diagnóstico e a tolerabilidade foram examinados e comparados entre os estudos de teste. RESULTADOS: O estudo envolveu 100 pacientes (54% mulheres), com 57 ± 12 anos. O EDX estava alterado em 47%. A adição de CN-PREP sozinho e NWR combinado com CN-PREP aumentou o rendimento diagnóstico para 69% e 72%, respectivamente. O CN-PREP provou ser bem tolerável, enquanto o NWR foi associado a maior intensidade de dor relacionada ao teste e taxa de descontinuação (9% vs. 0%). Considerando o EDX como teste de referência, a sensibilidade do CN-PREP foi de 85,1% e a especificidade de 58,5%. CONCLUSÃO: A combinação do CN-PREP com o EDX de rotina para pacientes com dor neuropática é viável e resulta em maior rendimento diagnóstico. Já a adição de NWR aos testes mencionados fornece pouca melhora nesse rendimento e é menos tolerável para o paciente. Mais estudos são necessários para determinar a real sensibilidade e especificidade do CN-PREP quando comparado ao padrão-ouro para diagnóstico de neuropatia de pequenas fibras, ou seja, a avaliação da densidade de fibras nervosas intraepidérmicas.

Wave V threshold among children with delayed speech and language, using brainstem evoked response audiometry – A cross-sectional study

Background: Brainstem Evoked Response Audiometry (BERA) is an objective test for audiometric assessment of children. As deprived linguistic skill is often associated with auditory impairment in initial years of life; early diagnosis and interventions are much needed. Aim and Objective: To detect Wave V, in the lowest intensity, as it is a reliable parameter to assess BERA threshold for hearing among different age group of children. Materials and Methods: This cross-sectional study included 250 children (n = 250) with impaired speech and 120 normal children. The case population was divided into four groups according to age – Group 1 (<1 year); Group 2 (1–3 years); Group3 (3–6 years); and Group 4 (6–12 years). Wave V threshold was determined by BERA (measure brainstem auditory evoked potential). Cases were also divided into two categories depending on unilateral or bilateral involvement of ear. Mean threshold of each group was compared with corresponding control group of similar age. The test of significance used was Mann–Whitney U-test. Intragroup comparison was done by Kruskal–Wallis test. Results: In Group 1, 91.7%; Group 2, 100%; Group 3; 88.6%, and Group 4; 85% of children were suffering from bilateral hearing loss. In all the groups, mean threshold was statistically significantly increased in comparison with control group. In intragroup comparison, there was no statistically significant difference of threshold among all the groups of cases in both of the ears. Conclusions: This study identified increased wave V threshold in children with impaired speech of all four groups. Thereby, it indicates the necessity of BERA as screening method.

Limiar Diferencial de mascaramento e potencial evocado auditivo de tronco encefálico em adultos normo-ouvintes com zumbido / Masking Level Difference and Auditory Brainstem ResponseIn Normal Hearing Adults With Tinnitus / Umbral de enmascaramiento diferencial y potencial evocado auditivo del tronco encefálico en adultos con audición normal y tinnitus

Introdução: O zumbido é uma ilusão auditiva consciente, uma sensação sonora não relacionada com uma fonte externa de estimulação. Objetivos: Caracterizar a Acufenometria, Limiar Diferencial de Mascaramento, o questionário de qualidade de vida Inventário de Desvantagem do Zumbido e Potencial Auditivo de Tronco Encefálico em adultos normo-ouvintes com zumbido, com a finalidade de comparar seus achados. Método: Vinte indivíduos do sexo feminino e masculino, entre 20 e 60 anos de idade, normo-ouvintes com queixa de zumbido, foram submetidos ao Acufenometria, Limiar Diferencial de Mascaramento, Inventário de Desvantagem do Zumbido e Potencial Evocado Auditivo de Tronco Encefálico. Resultados: AAcufenometriarevelou que o pitch médio foi de 4,3 KHz à orelha direita e 4,6 KHz à orelha esquerda. O loudness médio foi de 21,7 dBNS à orelha direita e 23,5 dBNS à orelha esquerda. O Limiar Diferencial de Mascaramento médio mostrou-se alterado. O Inventário de Desvantagem do Zumbido médio correspondeu à classificação de grau leve. O Potencial Evocado Auditivo de Tronco Encefálico apresentou parâmetros dentro da normalidade bilateralmente. Conclusão: Constatou-se que adultos normo-ouvintes com queixa de zumbido apresentam zumbido de pitch agudo bilateral com discreto impacto na qualidade de vida, condução adequada das vias auditivas até o tronco encefálico e comprometimento na identificação de sons na presença de ruído, demonstrando que o zumbido pode ter repercussões nas habilidades auditivas centrais. (AU)

Introduction: Tinnitus is a conscious auditory illusion, a sound perception unrelated to any external stimulus source. Objectives: To characterize the Acuphenometry, Masking Level Difference, the quality of life questionnaire Tinnitus Handicap Inventory and Auditory Brainstem Response in normal hearing adults with tinnitus, with the purpose of comparing the findings. Method: Twenty female and male individuals, between 20 and 60 years of age, normal hearing with complaints of tinnitus, underwent Acuphenometry, Masking Level Difference, Tinnitus Handicap Inventory and Auditory Brainstem Response. Results: The Acuphenometry showed the average pitch was 4.3 KHz to the right ear and 4.6 KHz to the left ear. The average loudness was 21.7 dBSL to the right ear and 23.5 dBs to the left ear. The average Masking Level Difference was altered. The average Tinnitus Handicap Inventory corresponded to the classification of mild grade. Auditory Brainstem Response showed parameters within normal range bilaterally. Conclusion: It was found that normal hearing adults with tinnitus complaints have bilateral acute pitch tinnitus with a slight impact on quality of life, appropriate conduction of auditory pathways to the brainstem and impaired identification of sounds in the presence of noise, demonstrating that tinnitus can have repercussions on central auditory skills. (AU)

Introducción: El tinnitus es una ilusión auditiva consciente, una sensación de sonido no relacionada con una fuente externa de estimulación. Objetivos: Caracterizar la coincidencia de tono y volumen, el umbral de enmascaramiento diferencial, el inventario de minusvalía para acúfenos y el potencial auditivo del tronco encefálico en adultos normoyentes con acúfenos, con el fin de comparar sus hallazgos. Método:Veinte sujetos masculinos y femeninos, con edades entre 20 y 60 años, audición normal con tinnitus, fueron sometidos a acúfenos, Umbral de Enmascaramiento Diferencial, Inventario de Desventajas de Tinnitus y Potenciales Evocados Auditivos del Tronco Encefalico. Resultados: La combinación de tono y volumen reveló que el tono promedio era de 4,3 KHz en el oído derecho y de 4,6 KHz en el oído izquierdo. Mientras que el volumen medio fue de 21,7 dBNS para el oído derecho y de 23,5 dBNS para el oído izquierdo. Se modificó el umbral diferencial de enmascaramiento promedio. El Inventario de Desventajas de Tinnitus promedio correspondió a la clasificación de grado leve. El Potenciales Evocados Auditivos del Tronco Encefalico presentó parámetros dentro del rango normal bilateralmente. Conclusión:Se encontró que los adultos normooyentes con quejas de tinnitus presentan tinnitus de tono alto bilateral con leve impacto en la calidad de vida, conducción adecuada de las vías auditivas al tronco encefálico y deterioro en la identificación de sonidos en presencia de ruido, demostrando que Tinnitus puede tener repercusiones en las habilidades auditivas centrales. (AU)

Contribuição do potencial evocado auditivo de estado estável na escolha do implante coclear ou aparelho de amplificação sonora em crianças com perda auditiva / Contribution of auditory steady state evoked potential to the election of cochlear implantation or hearing aid for children with hearing impairment / Contribución del potencial evocado auditivo de estado estable en la elección de implantación coclear o audífono en niños con deficiencia auditiva

Introdução: A deficiência auditiva em crianças prejudica a aquisição e o desenvolvimento da linguagem oral, o que pode ser minimizado com o diagnóstico e a confirmação da surdez nos primeiros meses de vida. O Potencial Evocado auditivo de estado estável (PEAEE) destaca-se diante dos demais potenciais evocados auditivos devido à facilidade de registro, à objetividade das respostas, à estimulação de várias frequências simultaneamente, em ambas as orelhas, além da identificação da audição residual. Objetivo: Verificar a contribuição do PEAEE na definição terapêutica (escolha do implante coclear ou aparelho de amplificação sonora) para a reabilitação auditiva de crianças. Método: Foram analisados os registros de 20 crianças de um mês a três anos de idade com perda auditiva neurossensorial de grau severo ou profundo bilateral e que foram submetidas ao PEAEE e ao potencial evocado auditivo de tronco encefálico frequência específica (PEATE-FE). Ambos realizados nas frequências de 500 Hz e 2000 Hz no equipamento Smart-EP Intelligent Hearing Systems®. Resultados: Houve diferença entre os exames quanto à ocorrência de resíduo auditivo, pois, um número significativo de indivíduos apresentou respostas ausentes no PEATE-FE e respostas presentes no PEAEE. Não ocorreu associação entre a presença de resíduo auditivo, o grau da perda e a idade da criança com o tipo de intervenção terapêutica. Conclusão: A presença de resíduo auditivo, a classificação do grau da perda e a idade da criança não influenciaram na conduta terapêutica final. (AU)

Introduction: Hearing impairment in children debilitates the acquisition and development of oral language, which can be minimized with diagnosis and confirmation of deafness in the first months of life. Auditory Steady State Evoked Potential (ASSEP) analysis stands out from others auditory evoked potentials due to the ease of recording, objectivity of the answers, stimulation of several frequencies simultaneously, in both ears, besides the identification of residual hearing. Purpose: Determine the contribution of the ASSEP for the therapeutic definition (election of cochlear implantation or hearing aid device) in hearing rehabilitation of children. Methods: The records of 20 children aged one month to three years with severe or profound bilateral neurosensory hearing loss, who were submitted to ASSEP and specific frequency brainstem auditory evoked potential (BAEP) analysis were analyzed. Both tests performed at frequencies of 500 Hz and 2000 Hz using the equipment Smart-EP Intelligent Hearing Systems®. Results: There was difference between the exams regarding the occurrence of residual hearing, since a significant number of individuals had absent responses on the BAEP and present responses on the ASSEP. There was no association between the presence of residual hearing, degree of hearing loss and the child's age with the type of therapeutic intervention. Conclusion: The presence of residual hearing, classification of the degree of loss and child's age exerted no influence on the final conduct. (AU)

Introducción: La deficiencia auditiva en niños hace daño a la adquisición y el desarrollo del lenguaje oral, que se puede minimizar con el diagnóstico y confirmación de la sordera en los primeros meses de vida. El Potencial Evocado de Estado Estable (PEAEE) se destaca de los demás potenciales evocados auditivos por la facilidad de registro, objetividad de las respuestas, estimulación de varias frecuencias simultáneamente, en ambos oídos, además de la identificación de audición residual. Objetivo: Verificar la contribución del PEAEE para la definición de las terapéuticas adoptadas (elección de implantación coclear o audífono) en la rehabilitación auditiva de niños. Método: Fueron analizados los registros de 20 niños de un mes a tres años de edad con pérdida auditiva sensorineural de grado severo o profundo bilateral y que fueron sometidas al PEAEE y al potencial evocado auditivo de tronco encefálico por frecuencia específica (PEATE-FE). Ambos se realizaron en las frecuencias de 500 Hz y 2000 Hz en el equipo Smart-EP Intelligent Hearing Systems®. Resultados: Hubo diferencia entre los exámenes con respecto a la ocurrencia de residuo auditivo, dado que, un número significativo de sujetos presentaron respuestas ausentes en PEATE-FE y respuestas presentes en PEAEE. No hubo asociación entre la presencia de residuo auditivo, el grado de pérdida y la edad del niño con el tipo de intervención terapéutica. Conclusión: La presencia de residuo auditivo, clasificación del grado de pérdida y edad del niño no influyeron en la conducta final. (AU)

The Effects of Monaural Stimulation on Frequency-Following Responses in Adults Who Can Sing in Tune and Those Who Cannot

Abstract Introduction Musicians have an advantage over non-musicians in detecting, perceiving, and processing nonverbal (i.e., environmental sounds, tones and others) and verbal sounds (i.e., consonant, vowel, phrases and others) as well as instrumental sounds. In contrast to the high skill of musicians, there is another group of people who are tone-deaf and have difficulty in distinguishing musical sounds or singing in tune. These sounds can originate in different ways, such as a musical instrument, orchestra, or the human voice. Objectives The objective of the present work is to study frequency-following responses (FFRs) in individuals who can sing in-tune and those who sing off-tune. Methods Electrophysiological responses were recorded in 37 individuals divided in two groups: (i) control group (CG) with professional musicians, and (ii) experimental group (EG) with non-musicians. Results There was homogeneity between the two groups regarding age and gender. The CG had more homogeneous responses in the latency of the FFRs waves when responses between the right and left ears were compared to those of the EG. Conclusions This study showed that monaural stimulation (right or left) in an FFR test is useful for demonstrating impairment of speech perception in individuals who sing off tune. The response of the left ear appears to present more subtlety and reliability when identifying the coding of speech sound in individuals who sing off tune.

The Effect of Different Stimulation Rates on Brainstem Auditory-Evoked-Potential Responses

Abstract Introduction Auditory-evoked potentials are influenced by several factors, including polarity, filter, stimulus intensity and stimulation rate. The presentation of higher rates of stimuli per second enables the collection of a greater number of responses in a given period of time, promoting a shorter testing time; however, the collected recordings are subject to changes related to wave morphology. Objectives To compare the brainstem auditory-evoked-potential responses with click stimulus with the most commonly used stimulation rates in the clinical practice. Methods The present cross-sectional analytical study was performed with fifteen participants of both genders and normal hearing thresholds. The brainstem auditoryevoked potential was performed at four different stimulation rates (21.1, 26.7, and 27.7 stimuli/s, and a rate determined based on a mathematical calculation using the a measurement of the transmission frequency of the power grid at the time of the examination). Results We observed that the rate of 21.1 stimuli/s showed the highest amplitudes for waves I, III, and V when compared with the other rates. The rate of 26.7 stimuli/s, when compared with 27.7 stimuli/s, showed a higher amplitude for wave V. The latency if wave V was significantly lower with the rate of 21.1 stimuli/s than with 27.7 stimuli/s. Conclusions The stimulation rate interferes with wave latencies and amplitudes; its decrease from 27.7 to 21.1 stimuli/s decreases the latency of wave V and increases the amplitues and improves the morphology of waves I, III and V. In addition, we found evidence that suggests an improvement in the visualization of wave III by adjusting the stimulation rate based on a measurement of the local transmission frequency of the power grid.

Mismatch Negativity in Children and Adolescents with Autism Spectrum Disorder

Abstract Introduction Individuals with autism spectrum disorder (ASD) have abnormalities in auditory perception and sensitivity. The mismatch negativity (MMN) component of the evoked potential demonstrates a brain detection response to an auditory change due to memory, and enables the identification of changes in the auditory system. Objectives To analyze MMN responses in children and adolescents with ASD and compare them with those of a control group. Methods Cross-sectional and comparative study. The sample was composed of 68 children and adolescents, divided into study group (SG), which contained those diagnosed with ASD, and the control group (CG), which contained those with typical development, normal hearing thresholds, and without hearing complaints. All participants were submitted to peripheral and central electrophysiological auditory evaluations. For the electrophysiological auditory evaluation and MMN recording, the electrodes were fixed in the following positions: Fz (active electrode), M1 and M2 (reference electrodes), and on the forehead (ground electrode). Auditory stimuli were presented in both ears simultaneously, with a frequency of 1,000 Hz for the frequent stimulus, and of 2,000 Hz for the rare stimulus, in an intensity of 80 dBNA. Results Latency and amplitude values were increased in the SG, with a statistically significant difference in comparison with the CG. In the MMN analysis, there was no statistically significant difference in the comparison between right and left ears and between genders. Conclusions Children and adolescents with ASD had higher latency and amplitude values in the MMN component than the individuals in the CG.

Subjective Visual Vertical and Vestibular Evoked Myogenic Potential in Meniere's disease,

Abstract Objective To evaluate otolith function by comparing the findings of the Subjective Visual Vertical, the cervical Vestibular Evoked Myogenic Potential and the ocular Vestibular Evoked Myogenic Potential tests in patients in the inter-crisis period of unilateral definite Meniere's disease. Methods The sample consisted of an experimental group (n = 22; 10 men and 12 women, mean age 47.32 ± 12.82 years) with definite unilateral Meniere's disease and a control group (n = 14; 5 men and 9 women, with a mean age of 41.64 ± 13.45 years). They all underwent vestibular evaluation by means of Subjective Visual Vertical with the bucket method and, cervical and ocular Vestibular Evoked Myogenic Potential tests. The data were collected and subjected to statistical analysis. Results The results of the comparison of the Subjective Visual Vertical, the cervical Vestibular Evoked Myogenic Potential, the ocular Vestibular Evoked Myogenic Potential and, the association of cervical Vestibular Evoked Myogenic Potential with the ocular Vestibular Evoked Myogenic Potential showed no significant difference, indicating concordance among the tests. Conclusion The identified abnormalities and the concordance between the combined proportion of the Subjective Visual Vertical, the cervical Vestibular Evoked Myogenic Potential and the ocular Vestibular Evoked Myogenic Potential findings indicate that the association of these three tests contributes to the identification of sustained and transient otolith dysfunction in the inter-crisis of unilateral definite Meniere's disease. Level of evidence 2.

Rhinal and hippocampal event-related potentials as epileptogenic zone markers in the pre-surgical evaluation of temporal epilepsies: a systematic review / Potenciais evocados rinais e hipocampais como marcadores da zona epileptogênica na avaliação pré-cirúrgica das epilepsias temporais: uma revisão sistemática

Abstract Background Cognitive event-related potentials (ERPs) allow for lateralization of the epileptogenic zone (EZ) to estimate the reserve of memory in the contralateral non-epileptogenic hemisphere, and to investigate the prognosis of temporal lobe seizure control in unilateral temporal lobe epilepsy (TLE). Objective To define the accuracy of cognitive evoked anterior mesial temporal lobe (AMTL-N400) and P600 potentials in detecting the epileptogenic zone in temporal lobe epilepsy (TLE), and second, to evaluate the possibility of using them as markers of cognitive outcome. Methods The systematic review using Medline/PubMed, Embase, and Lilacs database was conducted in September 2021. Only articles published in English from 1985 to June 2021 were included. We searched for studies with: (1) depth intracranial electroencephalography (iEEG) recordings analysis of rhinal and hippocampal activity (2) correlations between ERP results obtained in the mesial temporal regions (AMTL-N400 and P600) and the epileptogenic zone. Results Six out of the seven studies included in this review defined the laterality of the epileptogenic zone (EZ) during presurgical investigation using ERPs. One study showed that the contralateral AMTL-N400 predicts seizure control. Another study found correlation between the amplitudes of the right AMTL-N400 and postoperative memory performance. Conclusions There is evidence that the reduced amplitude of the AMTL-N400 has high accuracy in identifying the epileptogenic zone, as it does in estimating the extent of seizure control and memory impairment in postoperative patients.

Resumo Antecedentes Potenciais relacionados a eventos (PREs) cognitivos permitem a lateralização da zona epileptogênica (ZE), estimar a reserva de memória no hemisfério contralateral não-epileptogênico, e estimar o prognóstico pós-operatório em pacientes com epilepsia do lobo temporal (ELT) unilateral quanto ao controle de crises. Objetivo Definir a acurácia dos potenciais evocados cognitivos do lobo temporal mesial anterior (LTMA-N400) e P600 na detecção da zona epileptogênica na epilepsia do lobo temporal (ELT), além de avaliar a possibilidade de usá-los como marcadores de desfecho cognitivo. Métodos A revisão sistemática foi realizada em setembro de 2021 usando as bases de dados Medline/PubMed, Embase e Lilacs. Apenas artigos publicados em inglês no período entre 1985 e junho de 2021 foram incluídos. Buscamos estudos com: (1) análises dos registros de electroencefalografia intracraniana (EEGi) da atividade rinal e hipocampal (2) correlações entre os resultados de PREs obtidos nas regiões temporais mesiais (AMTL-N400 e P600) e a zona epileptogênica. Resultados Seis dos sete estudos incluídos nesta revisão definiram a lateralidade da zona epileptogênica (ZE) durante a investigação pré-cirúrgica usando PREs. Um estudo mostrou que o AMTL-N400 contralateral prediz o controle das crises. Outro estudo encontrou correlação entre as amplitudes do AMTL-N400 direito e o desempenho da memória pós-operatória. Conclusões Há evidências de que a amplitude reduzida do AMTL-N400 tem alta precisão na identificação da zona epileptogênica, assim como na estimativa do prognóstico quanto ao controle de crises a longo prazo e prejuízo da memória em pacientes submetidos à cirurgia ressectiva.

Características clínicas y los resultados de los Potenciales Evocados Visuales por Flash en niños menores de 5 años

Introducción: Los potenciales evocados visuales (PEV) evalúan la vía visual mediante pequeñas respuestas neuroeléctricas de la corteza occipital. Constituyen un examen no invasivo para determinar la función visual en prematuros, recién nacidos, lactantes, niños con malformaciones cerebrales enfermedades metabólicas o retraso mental. Objetivo: Describir las características clínicas y los resultados de los Potenciales Evocados Visuales por Flash en niños menores de 5 años en el periodo de diciembre de 2017 a diciembre de 2018. Materiales y Métodos: Diseño observacional, descriptivo, ambispectivo con componente analítico. Los pacientes incluidos niños de 0 a 5 años de edad que se realizaron PEV en el Hospital Pediátrico en el período de diciembre de 2017 a diciembre de 2018. Muestreo no probabilístico de casos consecutivos. Variables principales: Edad, sexo, procedencia, profesional que solicitó el estudio, motivo de solicitud del estudio, datos maternos y perinatales, resultados del PEV. Los datos fueron analizados con SPSSv 21, utilizando estadística descriptiva. Resultados: Se estudiaron 110 pacientes que se realizaron PEV, la mediana de edad fue de 32 meses, predominó el sexo masculino, procedieron del departamento Central (63,6%). La mayoría de los pacientes presentaban Parálisis cerebral infantil (PCI), los neurólogos solicitaron mayormente el estudio. De los antecedentes perinatales, se evidenció que, a menor edad gestacional, menor peso de nacimiento, menor Apgar y antecedente de hospitalización perinatal, los valores de latencia y amplitud para la onda P100 en ambos ojos presentaban alteraciones, siendo esta relación estadísticamente significativa. Conclusión: Aunque en su mayoría los resultados de PEV fueron normales existe una relación importante entre los antecedentes perinatales y la alteración del resultado especialmente con respecto al Apgar a los 1 min mostrando una relación inversa.

Introduction: Visual evoked potentials (VEP) evaluate the visual pathway through small neuroelectric responses from the occipital cortex. They constitute a non-invasive test to determine visual function in premature babies, newborns, infants, children with brain malformations, metabolic diseases or mental retardation. Objective: To describe the clinical characteristics and the results of Flash Visual Evoked Potentials in children under 5 years of age during the time period from December 2017 to December 2018. Materials and Methods: This was an observational, descriptive and ambispective design with an analytical component. The patients included children from 0 to 5 years of age who underwent VEP at the Pediatric Hospital in the period from December 2017 to December 2018. We used non-probabilistic sampling of consecutive cases. Main variables: Age, sex, place of residence, professional who requested the study, reason for requesting the study, maternal and perinatal data, VEP results. Data were analyzed with SPSSv 21, using descriptive statistics. Results: 110 patients who underwent VEP were studied, the median age was 32 months, the male sex predominated, most lived in the Central department (63.6%). Most of the patients had infantile cerebral palsy (ICP), neurologists most frequently requested the study. Using the perinatal history, we determined that a lower gestational age, lower birth weight, lower Apgar score, and a history of perinatal hospitalization were associated with alterations in the latency and amplitude values for the P100 wave in both eyes, this relationship was statistically significant. Conclusion: Although the majority of the VEP results were normal, there is an important relationship between the perinatal history and the alteration of the result, especially with respect to the Apgar at 1 min, which shows an inverse relationship.

Potenciais evocados auditivos de tronco encefálico em indivíduos com doença de Parkinson: revisão de literatura / Brainstem auditory evoked potentials in individuals with Parkinson's disease: literature review

Objetivo: investigar a integridade da via auditiva por meio do Potencial Evocado Auditivo de Tronco Encefálico (PEATE) em indivíduos com Doença de Parkinson (DP) por meio de uma revisão integrativa da literatura. Métodos: foram utilizadas as bases de dados Embase, Google acadêmico, Scielo, bem como o portal eletrônico completo da Biblioteca Virtual da Saúde, com os seguintes descritores: DP (Parkinson Disease ou Parkinsonian Disorders) e PEATE (Evoked Potentials, Auditory, Brain Stem ou Evoked Potentials, Auditory). Foram selecionados artigos nacionais e internacionais, sem limitação de ano ou idioma. Os estudos foram descritos e analisados qualitativamente e quantitativamente quanto à latência absoluta e à amplitude das ondas I, III e V, e quanto aos interpicos I-III, III-V e I-V. Resultados: após exclusão dos títulos repetidos, 420 artigos foram encontrados, sendo que 17 atenderam aos critérios de inclusão. Nos resultados do PEATE, estudos descreveram o aumento da latência de todas as ondas, principalmente das ondas III e V e, também, aumento dos interpicos I-V e III-V. Conclusão: indivíduos com DP apresentam neurodegeneração das vias auditivas centrais com diminuição na velocidade de transmissão neural do estímulo acústico.

Purpose: investigate the integrity of the auditory pathway through the Brainstem Auditory Evoked Potential (BAEP) in individuals with Parkinson's Disease (PD) through an integrative literature review. Methods: Embase, Academic Google, Scielo databases were used, as well as the complete electronic portal of the Virtual Health Library, with the following descriptors: PD (Parkinson Disease or Parkinsonian Disorders) and BAEP (Evoked Potentials, Auditory, Brain Stem or Evoked Potentials, Auditory). National and international articles were selected, without limitation of year or language. The studies were described and analyzed qualitatively and quantitatively regarding the absolute latency and amplitude of waves I, III and V, and regarding the interpeaks I-III, III-V and I-V. Results: After excluding repeated titles, 420 articles were found, however only 17 met the inclusion criteria. In the ABR results, studies described the increase in latency of all waves, especially waves III and V, and also an increase in interpeaks I-V and III-V. Conclusion: individuals with PD present neurodegeneration of the central auditory pathways with a decrease in the neural transmission speed of the acoustic stimulus.

Impact of Reconstructing Intercostal Artery on Spinal Cord Circulation During Open Surgery for Thoracoabdominal Aortic Aneurysm

ABSTRACT Introduction: We evaluated the outcomes of the selective intercostal artery reconstruction for preventing spinal cord injury during thoracoabdominal aortic aneurysm repair. Methods: We retrospectively assessed 84 consecutive patients who underwent thoracoabdominal aortic aneurysm repairs between 2004 and 2016. The mean age of the patients was 57.3 years. We performed preoperative multidetector computed tomography in 74 patients (88.0%) to identify the Adamkiewicz artery. Spinal cord injury preventive measures included motor evoked potential monitoring, hypothermia induction, Adamkiewicz artery or other intercostal artery reconstruction, and cerebrospinal fluid drainage. Results: The hospital death rate was 5.9%, and paraplegia occurred in four patients (4.7%). The Adamkiewicz artery or other intercostal arteries were reconstructed selectively in 46 patients (54.7%). Of these patients, 41 underwent postoperative multidetector computed tomography, which revealed occlusion of the reconstructed grafts in 23 patients (56.0%). There was no paraplegia in the patients who underwent reconstruction of the Adamkiewicz artery, which was patent on postoperative multidetector computed tomography. Univariate analysis showed no significant effect of various risk factors on the development of spinal cord injury. Conclusion: Outcome of open surgery for thoracoabdominal aortic aneurysm in our institution regarding spinal cord injury was satisfactory. The benefits of Adamkiewicz artery reconstruction remain inconclusive, and further larger studies are required to identify its validation for spinal cord protection in thoracoabdominal aortic aneurysm repair.

Role of visual evoked potential as a window to detect functional changes that occur without signs of diabetic retinopathy in fundoscopy: Case series involving symptomatic overt diabetic pregnant women

Diabetic retinopathy (DR) is a microvascular complication associated with diabetes mellitus. Pregnancy is a major risk factor for DR in diabetic women. Recent evidenced suggests that in course of DR functional changes including damage of pre-ganglionic and ganglionic cells in retina precede structural microvascular changes. A number of studies in the past have highlighted the role of pattern visual evoked potential (VEP) in detecting such functional changes. However, the study of VEP changes in diabetic pregnancies remains unexplored. This case series has the objective of exploring VEP changes in symptomatic OVD cases, who had no signs of DR on fundoscopy. We present two cases of overt diabetic women who complaint of straining of eyes, headache, and difficulty in reading during pregnancy. Complete ophthalmic examination was done in both the cases followed by a VEP test. VEP test was done as a part of a research project. The ethical clearance for the project was obtained from the Institute’s Ethics Committee before the commencement of the study. Fundoscopic examination in both cases revealed that the retina was within normal limits with no signs of retinopathy. In Case 1, P100 latency was increased for the left eye and was normal for the right eye during the first visit. While P100 latency was increased for both left and right eye during the second visit. There was a substantial increase in P100 latency for both eyes in second visit as compared to first visit. In Case 2, P100 latency was increased for both left and right eye and amplitude decreased for the left eye. This is a case series consisting of symptomatic overt diabetic pregnant women who had increased P100 latency despite no signs of retinopathy in fundoscopy. The previous studies have reported that multiple follow-ups with ophthalmoscopy may not be cost-effective in diabetic pregnant women. VEP provides a window for detection of early functional changes that may help identify at risk patients for follow-up and early intervention.

Research status and prospect on the cerebral vision in myopic patients / 中华实验眼科杂志

The visual signal generated by the eye receiving external light stimulation reaches the visual center through the visual pathway and is processed and integrated by the visual center to form a subjective sensation called cerebral vision.Cerebral vision reflects the function of the whole visual nervous system from the retina to the visual cortex.Abnormal cerebral vision has been found in myopes using electrophysiology, magnetic resonance imaging (MRI) and functional near-infrared spectroscopy (fNIRS). The abnormal electrophysiological results are mainly found in patients with high myopia and pathological myopia.MRI shows abnormal changes in the structure and function of several vision-related brain regions in patients with high myopia.Recently, by applying near-infrared brain function imaging technology combined with self-developed equipment, our team conducted a series of studies on the brain function of myopic patients and found that adult patients with moderate myopia and patients with pathological myopia have the abnormal cerebral vision.The mechanism of neural regulation of eye accommodation in myopic children needs further investigation.In this article, we reviewed the current status and outlook of myopic brain vision research in terms of myopia classification, myopic brain vision research methods, and myopic visual electrophysiology, MRI, and fNIRS studies.

Distinction and processing of common artifact in clinical visual electrophysiology / 中华实验眼科杂志

Objective:To explore the common causes and solutions for artifacts in clinical visual electrophysiological examination.Methods:A cross-sectional study was performed.The clinical visual electrophysiological examination results of 25 001 cases were collected from 2012 to 2020 at the Southwest Hospital/Southwest Eye Hospital, Third Military Medical University (Army Medical University). Artifacts were identified and analyzed according to the standard waveform provided by the International Society for Clinical Electrophysiology of Vision.The characteristics and causes of the artifact were analyzed.The solutions to reduce and eliminate the artifact were proposed.This study adhered to the Declaration of Helsinki.The study protocol was approved by the Ethics Committee of the Southwest Hospital/Southwest Eye Hospital, Third Military Medical University (Army Medical University) (No.KY2020053).Results:There were 60 typical artifacts identified among the 25 001 cases.Common causes of the artifacts were classified as three categories, the factors related to subjects, environment, or instruments.Among the 60 cases, 42(70.0%) were caused by tension in head and facial muscles of patients, 9(15.0%) due to blinking of patients, 4(6.7%) resulted from 50 Hz power frequency artifact, 2(3.3%) arisen from abnormal amplifier, and 3(5.0%) for other reasons.The strategies to avoid artifact were as follows.First, examiners could inform patients of the examination process in advance to help patients to relax and avoid the influencing factors, such as muscle tension in head and face, blinking, inattention and so on; second, high-quality 50 Hz hardware wave trap was recommended to reduce 50 Hz artifact, with good ground connection and removing of the high-power electrical appliances near the visual electrophysiological instrument; third, clean the skin sufficiently to reduce the reference electrode impedance to less than 1 kΩ.Conclusions:There is a variety of artifact waveforms and causes.The technicians should make correct judgments and handle the artifact in time to provide more accurate examination results.The doctors should know about artifact, which is helpful for better interpretation of visual electrophysiological examination reports.