No abstract available.
Audiometry, Evoked Response ; Edema ; Masks

Objective: To assess the usage of the “Baah” Test compared to the AABR (Automated Auditory Brainstem Response) in detecting hearing loss of neonates in the community setting. Methods: This is a retrospective cross-sectional study. The targeted sample population are infants less than a month old who underwent screening at a testing facility in Malolos, Bulacan spanning the years 2011 and 2012. Results: A total of 201 infants were included in the study, with a mean age of 10.77 days with a standard deviation of 7.79. The ratio of males to females was almost equal at 1:1.01. For infants who passed hearing screening on at least one ear, 96% (193 infants) correlated with the results of “Baah” testing. For those with bilateral refer results on AABR, 4 out of the 6 correlated with the “Baah” Test. Conclusion There is potential in using the “Baah” Test as a tool for hearing loss assessment of infants in situations wherein the usual hearing screening tests are inaccessible. It makes use of little resources, and though it does have its limitations in assessing for unilateral hearing loss (as the test cannot test ears in isolation), it would be able to identify infants likely to have bilateral hearing loss.
Audiometry, Evoked Response ; Infant, Newborn

No abstract available.
Audiometry, Evoked Response* ; Brain Stem* ; Humans

BACKGROUND AND OBJECTIVES:Electrocochleography is the only proven investigation and diagnostic tool to demonstrate the endolymphatic hydrops at this time. We designed this study to assess the characteristics of transtympanic electrocochleographic findings and to estimate the clinical value of the test results in the patients with Meniere's disease. MATERIALS AND METHOD:Electrocochleographic duration and amplitude were measured in a clinically defined definite Meniere's disease group and the results were compared with those from a normal hearing control group. RESULTS:The summating potential (SP)/action potential (AP) amplitude ratio was significantly different among study groups with 0.40+/-.10 in the bilateral Meniere's group, 0.34+/-.08 in the unilateral Meneire's group and 0.22+/-.08 in the normal group (p<0.01). The elevated SP/AP ratio in the patients with such a relatively long duration of Meniere's disease in this study was mainly due to the decreased AP amplitude rather than the enhanced SP amplitude. CONCLUSION:Measuring electrocochleography and demonstrating the elevated SP/AP ratio could be quite valuable to diagnose the patients with Meniere's disease. The recognition of decreased AP amplitude might be helpful to understand the cochlear pathologic status in the patients with Meniere's disease.
Audiometry, Evoked Response* ; Endolymphatic Hydrops ; Hearing ; Humans ; Meniere Disease*

No abstract available.
Action Potentials* ; Atrial Natriuretic Factor* ; Audiometry, Evoked Response* ; Reference Values*

The etiology and pathophysiology of Meniere's disease (MD) remain controversial and incompletely understood. Diagnosis of MD is decided according to the diagnostic criteria proposed by the American Academy of Otolaryngology-Head and Neck Surgery (AAO) (1995), which is based on clinical symptoms. It would be of great value to have an objective clinical test for the diagnosis of endolymphatic hydrops. Various tests like electrocochleography, vestibular evoke myogenic potential and cochlear hydrops analysis masking procedures have been applied for detecting endolymphatic hydrops. Any of single objective tests is not perfect for the diagnosis of MD. However, considering AAO guideline is not enough for the diagnosis, additive objective tests for MD become essential. We evaluated the objective tests for MD and also surveyed preferred tests among Korean otologic society members.
Audiometry, Evoked Response ; Edema ; Endolymphatic Hydrops ; Masks ; Meniere Disease ; Neck

OBJECTIVE: Determine the frequency-specific thresholds of auditory steady state response (ASSR) of Filipino children with absent auditory brainstem response (click-ABR) results.METHODS: This is a cross-sectional study analyzing the frequency-specific thresholds of auditory steady state response (ASSR) of Filipino children with absent auditory brainstem response (click-ABR) results. The study population comprised of 99 pediatric patients referred for hearing assessment using electrophysiologic techniques at the Ear Unit of the Philippine General Hospital. The subjects underwent hearing threshold evaluation using both evoked-potential techniques (click ABR and ASSR) within a one-month period from January 2009 to March 2014. The ASSR results of patients with absent click-ABR were collected and analyzed.RESULTS: There were 99 patients who underwent both ABR and ASSR. Of the 65 patients with absent ABR thresholds results, 13 patients had unilateral absent ABR while 52 had bilateral absent ABR results. The data of hearing tests from the combined 117 ears with absent ABR hearing tests were collected. The proportion of children with ASSR thresholds with absent ABR per frequency were -500 Hz- 45/117 (38.5%); -1000 Hz- 76/117 (64.0%); -2000 Hz- 63/117 (53.8%); and -4000 Hz- 41/117 (35.0%). The proportion of children with ASSR thresholds with absent ABR per number of frequencies were: -4 frequencies- 19/117 (16.2%); -3 frequencies- 32/117 (27.4%); -2 frequencies- 22/117 (18.8%); and -1 frequency- 44/117 (37.6%)CONCLUSION: In the absence of click- ABR response, ASSR may provide information about the levels of severe to profound hearing loss among children. The criteria of selection of candidates for intervention (hearing aids or cochlear implantation) should include results from hearing evaluation not only from behavioral and ABR thresholds but also from ASSR thresholds. This may ensure that exclusion of some children with severe and profound hearing loss who may benefit from the intervention will be minimized.
Human ; Male ; Female ; deafness ; Audiometry, Evoked Response ; hearing ;

Objective The tests of three types of auditory evoked potentials （AEPs） were performed on normal young adults, to understand the frequency characteristics of different testing methods and the relationship between response threshold and pure tone audiometry threshold of different methods, and to discuss the forensic value of 3 types of AEPs to evaluate hearing function. Methods Twenty normal young adults were selected, their standard pure tone audiometry threshold, short-term pure tone audiometry threshold and the response threshold of 3 types of AEPs （tone burst-auditory brainstem response, 40 Hz auditory event-related potential and slow vertex response） at 0.5 kHz, 1.0 kHz, 2.0 kHz and 4.0 kHz were recorded. The relationship between the response threshold and standard pure tone audiometry threshold, short-term pure tone audiometry threshold of 3 types of AEPs at different frequencies as well as the differences between different types of AEPs were analyzed. Results The short-term pure tone audiometry threshold was higher than the standard pure tone audiometry threshold at each frequency. The response threshold and standard pure tone audiometry threshold of the 3 types of AEPs all had a certain correlation, and the response threshold of the 3 types of AEPs was higher than short-term pure tone audiometry threshold and standard pure tone audiometry threshold at each frequency. The differences in the differences between the response threshold and standard pure tone audiometry threshold of the 3 types of AEPs at different frequencies had statistical significance. Linear regression mathematical models were established to infer the standard pure tone audiometry threshold （hearing level） from response threshold （sound pressure level） of 3 types of AEPs of normal young adults. Conclusion When using response threshold of different types of AEPs to estimate pure tone audiometry threshold, conversion and correction are needed. Combined use of different types of AEPs could improve the accuracy of hearing function evaluation.
Audiometry, Evoked Response ; Audiometry, Pure-Tone ; Auditory Threshold ; Evoked Potentials, Auditory ; Evoked Potentials, Auditory, Brain Stem ; Hearing ; Humans ; Young Adult

BACKGROUND AND OBJECTIVES: Electrocochleography (ECoG) is a sensitive evoked-response test for evaluating changes in cochlear function. We investigated the extratympanic ECoG in noise-induced temporary and permanent threshold shift to evaluate the usefulness of ECoG in the early detection and monitoring of noise-induced hearing loss (NIHL). SUBJECTS AND METHOD: Fifteen healthy ears were exposed to noise to induce temporary threshold shift (TTS). Pure-tone audiometry and ECoG were performed before (control-group), immediately after (TTS-group), and 24 hours after the exposure. And ECoG was measured in 27 ears with noise-induced permanent threshold shift (PTS-group). RESULTS: The mean amplitude of SP (summating potential) was greatest in the TTS-group. The largest increment in the SP/AP (action potential) ratio was also observed in the TTS-group. The mean ratios of control-, TTS-, and PTS-group were 0.22+/-0.11, 0.46+/-0.18 and 0.37+/-0.10, respectively. The PTS-group showed the smallest mean amplitude of AP. CONCLUSION: The results of this study suggest that SP, AP and the SP/AP ratio might be sensitive parameters reflecting the changes of cochlear function in NIHL.
Audiometry, Evoked Response* ; Audiometry, Pure-Tone ; Ear ; Hearing Loss, Noise-Induced* ; Noise

BACKGROUND AND OBJECTIVES: Early detection and monitoring are the most important measures in the prevention of development and progression of noise-induced hearing loss (NIHL). Electrocochleography (ECoG) is known as a sensitive evoked-response test to evaluate changes in cochlear function. Through the investigation about the changes of ECoG in development of noise-induced temporary threshold shift (NITTS), we intended to evaluate the usefulness of ECoG on early detection of NIHL. MATERIALS AND METHODS: Ten healthy adult participants (20 ears) were exposed to 90.3~105.0 dB broad-band noise for 3 hours in a computer-game room. Pure-tone audiometry (PTA) and ECoG were performed before the exposure, immediately after and 24 hours after the exposure. RESULTS: Before the exposure, mean PTA threshold was 6.1+/-2.6 dB, which was significantly increased to 12.0+/-3.2 dB immediately after the exposure, and recovered to 5.5+/-2.4 dB at 24 hours later. Marked increment of SP/AP (summating potential/action potential) ratio was observed simultaneously with the development of TTS and was normalized after its resolution. The mean ratio was 0.23+/-0.17 before the exposure, 0.43+/-0.16 on TTS phase, and 0.24+/-0.18 on resolution. CONCLUSION: The result of this study suggest that SP/AP ratio of ECoG might have applicability for early detection and monitoring of NIHL.
Adult ; Audiometry, Evoked Response* ; Audiometry, Pure-Tone ; Hearing Loss, Noise-Induced ; Humans ; Noise