Normative data for TM electrocochleography measures.

OBJECTIVE: Establish normative data for tympanic electrocochleography (TM ECochG) parameters in normal hearing adults without Ménière's disease's (MD) symptoms. Describe TM ECochG variables that help to distinguish normal from MD ears. MATERIAL AND METHODS: We enrolled 100 subjects (N = 200 ears), 59 females, aged between 19 and 71 years from 09/2010 to 04/2014. Inclusion criteria: normal otomicroscopy, hearing thresholds ≤25 dB nHL from 250 to 4000 Hz, normal tympanogram, no symptoms of MD according to the AAO-HNS 1995 criteria and Gibson's score <7. We excluded subjects with dizziness, aural fullness or other symptoms of endolymphatic hydrops. The following parameters were analyzed: SP/AP amplitude ratio, SP/AP area ratio and the difference between AP latency with rarefaction and condensation stimuli. RESULTS: There was no significant difference between right and left ears (Intraclass correlation coefficient < 0.6). SP/AP amplitude ratio varied between 0.084 and 0.356 and SP/AP area ratio between 0.837 and 1.671 (percentiles 5 and 95). The AP latency difference to rarefaction and condensation clicks was between 0.0 and 0.333 ms. CONCLUSION: Normative data for TM ECochG parameters were established in 100 normal hearing subjects without MD. These data can be used to distinguish normal from pathological findings and in follow-up of MD patients.

Are auditory steady-state responses a good tool prior to pediatric cochlear implantation?

INTRODUCTION: ASSR allow frequency-specific evaluation in intensities up to 120dB HL and detection of residual hearing in patients with severe-to-profound hearing loss. AIM: to compare ASSR thresholds and behavioral test results in children with suspected severe-to-profound hearing loss. METHODS: Cross sectional study to compare ASSR and behavioral responses (VRA or audiometry) in 63 pediatric cochlear implant candidates (126 ears) aged between 6 and 72 months. We included children with normal otomicroscopy, absent responses to click-ABR and otoaccoustic emissions. We excluded children with inner ear malformations, auditory neuropathy spectrum disorder or who did not complete VRA or achieve EEG noise<30nV during the ASSR test. Air-conduction ASSR stimuli were continuous sinusoidal tones presented at 0.5, 1, 2 and 4kHz starting at 110dB HL. Behavioral thresholds were acquired with warble tones presented at 0.5, 1, 2 and 4kHz in each ear through insert or head phones at maximum presentation level of 120dB HL. RESULTS: Behavioral thresholds were obtained in 36.7% (185/504) of all frequencies in all subjects, 9% in intensities >110dB HL. Among 504 ASSR measurements, 53 thresholds were obtained (10.5%). Overall 89.5% of the tested frequencies did not show any response at 110dB HL. Most responses were at 500Hz. Mean differences between behavioral and ASSR thresholds varied from 0.09 to 8.94dB. Twenty-seven comparisons of behavioral and ASSR thresholds were obtained: 12 at 0.5kHz, 9 at 1kHz, 5 at 2kHz and 1 at 4kHz. Absent responses were observed in both tests in 38.1% at 0.5kHz, 52.4% at 1kHz, 74.6% at 2kHz and 81.0% at 4kHz. Specificity was>90% at 1, 2 and 4kHz. In ears with no behavioral response at 120dB HL all ASSR thresholds were in the profound hearing loss range, 90% of them were ≥110dB HL. CONCLUSION: Among 63 pediatric CI candidates, absent responses to high-intensity ASSR was the major finding (specificity>90%) predicting behavioral thresholds in the profound hearing loss range. These findings can be helpful to confirm the decision for cochlear implantation.

Evaluation of residual hearing in cochlear implants candidates using auditory steady-state response.

CONCLUSION: The correlations between behavioral and auditory steady-state response (ASSR) thresholds were significant at 500, 1000, 2000, and 4000 Hz. ASSR presented high sensitivity and specificity in the detection of residual hearing in cochlear implant candidates when compared with warble-tone audiometry. OBJECTIVES: To assess residual hearing in cochlear implant candidates by comparing the electrophysiological thresholds obtained in dichotic single-frequency ASSR with behavioral thresholds at 500, 1000, 2000, and 4000 Hz. METHODS: This was a comparative study between ASSR and warble-tone audiometry thresholds in 40 cochlear implant candidates (80 ears) before cochlear implantation with bilateral severe-to-profound sensorineural hearing loss. RESULTS: Thresholds were obtained in 62.5% of all frequencies evaluated in warble-tone audiometry and in 63.1% in the ASSR. ASSR sensitivity was 96% and specificity was 91.6%. Mean differences between behavioral and ASSR thresholds did not reach significance at any frequencies. Strong correlations between behavioral and ASSR thresholds were observed in 500, 1000, and 2000 Hz and moderate in 4000 Hz, with correlation coefficients varying from 0.65 to 0.81. On 90% of occasions, ASSR thresholds were acquired within 10 dB of behavioral thresholds.

Are Auditory Steady-State Responses Useful to Evaluate Severe-to-Profound Hearing Loss in Children?

OBJECTIVE: To evaluate Auditory Steady-State Responses (ASSR) at high intensities in pediatric cochlear implant candidates and to compare the results to behavioral tests responses. METHODS: This prospective study evaluated 42 children with suspected severe-to-profound hearing loss, aged from 3 to 72 months. All had absent ABR and OAE responses. ASSR were evoked using binaural single frequency stimuli at 110 dB HL with a 10 dB down-seeking procedure. ASSR and behavioral test results were compared. RESULTS: Forty-two subjects completed both ASSR and behavioral evaluation. Eleven children (26.2%) had bilateral responses. Four (9.5%) showed unilateral responses in at least two frequencies, all confirmed by behavioral results. Overall 61 ASSR responses were obtained, most (37.7%) in 500 Hz. Mean thresholds were between 101.3 and 104.2 dB HL. Among 27 subjects with absent ASSR, fifteen had no behavioral responses. Seven subjects showed behavioral responses with absent ASSR responses. No spurious ASSR responses were observed at 100 or 110 dB HL. CONCLUSION: ASSR is a valuable tool to detect residual hearing. No false-positive ASSR results were observed among 42 children, but in seven cases with absent ASSR, the test underestimated residual hearing as compared to the behavioral responses.

Comparative study between pure tone audiometry and auditory steady-state responses in normal hearing subjects.

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.

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. .

Comparação entre respostas auditivas de estado estável e avaliação comportamental em crianças candidatas ao implante coclear / Comparison between Auditory Steady-State Responses and behavioral audiometry in pediatric cochlear implant candidates

INTRODUÇÃO: As Respostas Auditivas de Estado Estável permitem avaliação frequência específica em intensidades de até 120 dB NA e a detecção de audição residual em pacientes com perda auditiva severo-profunda. O objetivo deste estudo é comparar os limiares à RAEE e os resultados da avaliação comportamental em crianças com suspeita de surdez severo-profunda. MÉTODO: Estudo transversal para comparar respostas à RAEE e por audiometria com reforço visual (VRA) em 63 crianças candidatas ao implante coclear (126 orelhas) com idade entre 6 e 72 meses. Foram incluídas crianças com otomicroscopia normal, ausência de respostas ao PEATE clique a 90 dB NA e às emissões otoacústicas. Foram excluídas crianças com malformações de orelha interna, doenças do espectro da neuropatia auditiva, ou que não completaram a avaliação comportamental ou não atingiram ruído eletroencefalográfico < 30 nV durante a RAEE. Foram utilizados estímulos com tons contínuos sinusoidais (100% AM e 20% FM) nas frequências de 500, 1000, 2000 e 4000 Hz em intensidade máxima de 110 dB NA. Os limiares à VRA foram obtidos por tom warble nas frequências de 500, 1000, 2000 e 4000 Hz em cada orelha através de fones de inserção (ER-5A) ou tipo casco (TDH-39). A intensidade máxima de estimulação foi de 120 dB NA em cada frequência. RESULTADOS: Limiares comportamentais foram obtidos em 36,7% (185/504) de todas as frequências em todas as crianças, 9% em intensidade maior que 110 dB NA. Entre as 504 medidas da RAEE em 63 indivíduos, 53 limiares foram obtidos (10,5%). Ao todo, 89,5% das frequências testadas não apresentaram nenhuma resposta em 110 dB NA. A distribuição dos limiares à RAEE foi semelhante à da avaliação comportamental. A maioria das respostas foram em 500 Hz, diminuindo nas frequências agudas. A diferença média entre os limiares à VRA e à RAEE variou entre 0,09 e 8,94 dB. Foram realizadas 27 comparações entre RAEE e VRA: 12 em 500 Hz, 9 em 1000 Hz, 5 em 2000 Hz e 1 em 4000 Hz. Respostas...

Introduction and Objective: ASSR allows frequency-specific evaluation in intensities up to 120 dB HL and detection of residual hearing in patients with severe-toprofound hearing loss. The aim of this study was to compare ASSR thresholds and behavioral test results in children with suspected severe-to-profound hearing loss. Methods: A cross sectional study was carried out to compare ASSR and Visual Reinforcement Audiometry (VRA) responses in 63 pediatric cochlear implant candidates (126 ears) aged between 6 to 72 months. We included children with normal otomicroscopy findings, absent responses to click-ABR at 90 dB HL and otoaccoustic emissions. We excluded children with inner ear malformations, auditory neuropathy spectrum disorder or who did not complete VRA or achieve EEG noise < 30 nV during the ASSR test. Air-conduction ASSR stimuli were continuous sinusoidal tones (100% AM and 20% FM) presented at 0.5, 1, 2 and 4 kHz starting at the maximum presentation level of 110 dB HL. VRA thresholds were acquired with warble tones presented at 0.5, 1, 2 and 4 KHz in each ear through ER-tone 5A or TDH-39 phones. Maximum presentation level was 120 dB HL for each frequency. Results: Behavioral thresholds were obtained in 36.7% (185/504) of all frequencies in all subjects, 9% were in intensities > 110 dB HL. Among 504 ASSR measurements from 63 subjects, 53 thresholds were obtained (10.5%). Overall 89.5% of the tested frequencies did not show any response at 110 dB HL. The distribution of ASSR responses was similar to the behavioral test results. Most responses were at 500 Hz, decreasing among the higher frequencies. Mean differences between behavioral and ASSR thresholds varied from 0.09 to 8.94 dB. Overall, 27 comparisons of behavioral and ASSR thresholds were obtained: 12 at 0.5 KHz, 9 at 1 KHz, 5 at 2 KHz and 1 at 4 KHz. Absent responses were observed in both tests in 38.1% at 0.5 KHz, 52.4% at 1 KHz, 74.6% at 2 KHz and 81.0% at 4 KHz. The specificity was > 90% at 1,...