Monitoring Cochlear Health With Intracochlear Electrocochleography During Cochlear Implantation: Findings From an International Clinical Investigation.

OBJECTIVES: Electrocochleography (ECochG) is emerging as a tool for monitoring cochlear function during cochlear implant (CI) surgery. ECochG may be recorded directly from electrodes on the implant array intraoperatively. For low-frequency stimulation, its amplitude tends to rise or may plateau as the electrode is inserted. The aim of this study was to explore whether compromise of the ECochG signal, defined as a fall in its amplitude of 30% or more during insertion, whether transient or permanent, is associated with poorer postoperative acoustic hearing, and to examine how preoperative hearing levels may influence the ability to record ECochG. The specific hypotheses tested were threefold: (a) deterioration in the pure-tone average of low-frequency hearing at the first postoperative follow-up interval (follow-up visit 1 [FUV1], 4 to 6 weeks) will be associated with compromise of the cochlear microphonic (CM) amplitude during electrode insertion (primary hypothesis); (b) an association is observed at the second postoperative follow-up interval (FUV2, 3 months) (secondary hypothesis 1); and (c) the CM response will be recorded earlier during electrode array insertion when the preoperative high-frequency hearing is better (secondary hypothesis 2). DESIGN: International, multi-site prospective, observational, between groups design, targeting 41 adult participants in each of two groups, (compromised CM versus preserved CM). Adult CI candidates who were scheduled to receive a Cochlear Nucleus CI with a Slim Straight or a Slim Modiolar electrode array and had a preoperative audiometric low-frequency average thresholds of ≤80 dB HL at 500, 750, and 1000 Hz in the ear to be implanted, were recruited from eight international implant sites. Pure tone audiometry was measured preoperatively and at postoperative visits (FUV1 and follow-up visit 2 [FUV2]). ECochG was measured during and immediately after the implantation of the array. RESULTS: From a total of 78 enrolled individuals (80 ears), 77 participants (79 ears) underwent surgery. Due to protocol deviations, 18 ears (23%) were excluded. Of the 61 ears with ECochG responses, amplitudes were < 1 µV throughout implantation for 18 ears (23%) and deemed "unclear" for classification. EcochG responses >1 µV in 43 ears (55%) were stable throughout implantation for 8 ears and compromised in 35 ears. For the primary endpoint at FUV1, 7/41 ears (17%) with preserved CM had a median hearing loss of 12.6 dB versus 34/41 ears (83%) with compromised CM and a median hearing loss of 26.9 dB ( p < 0.014). In assessing the practicalities of measuring intraoperative ECochG, the presence of a measurable CM (>1 µV) during implantation was dependent on preoperative, low-frequency thresholds, particularly at the stimulus frequency (0.5 kHz). High-frequency, preoperative thresholds were also associated with a measurable CM > 1 µV during surgery. CONCLUSIONS: Our data shows that CM drops occurring during electrode insertion were correlated with significantly poorer hearing preservation postoperatively compared to CMs that remained stable throughout the electrode insertion. The practicality of measuring ECochG in a large cohort is discussed, regarding the suggested optimal preoperative low-frequency hearing levels ( < 80 dB HL) considered necessary to obtain a CM signal >1 µV.

Assessment of Hidden Hearing Loss in Normal Hearing Individuals with and Without Tinnitus.

OBJECTIVES: To evaluate the functions of cochlear structures and the distal part of auditory nerve as well as dead regions within the cochlea in individuals with normal hearing with or without tinnitus by using electrophysiological tests. MATERIALS AND METHODS: Nine individuals (ages: 21-59 years) with normal hearing with tinnitus were included in the study group. Thirteen individuals (ages: 25-60 years) with normal hearing without tinnitus were included in the control group. Immitancemetric examination, pure-tone audiometry (125Hz-16kHz), speech audiometry in quiet and noise environments, transient evoked otoacoustic emissions (TEOAEs), distortion product otoacoustic emissions (DPOAEs), threshold equalizing noise (TEN test (500Hz-4kHz), and ECochG tests, Beck Depression Questionnaire, Tinnitus Handicap Questionnaire, and Visual Analog Scale were performed. RESULTS: In the study group, three patients were found to have a minimal depression and six were found to have a mild depression. In pure-tone audiometry, the threshold (6-16 kHz) in the study group was significantly higher than that of the control group at all frequencies. In the study group, lower performance scores were obtained in speech discrimination in noise in both ears. In the control group, no dead region was detected in the TEN test whereas 75% of subjects in the study group had dead regions. DPOAE and TEOAE responses between study and control group subjects were not different. In the ECochG test, subjects in the study group showed an increase in the summating potential/action potential (SP/AP) ratio in both ears. CONCLUSION: Determination of the SP/AP ratio in patients with tinnitus may be useful in diagnosing hidden hearing loss. Detection of dead regions in 75% of patients in the TEN test may indicate that inner hair cells may be responsible for tinnitus.

Faster automatic ASSR detection using sequential tests.

Objective: Objective Response Detection (ORD) can be used for auditory steady-state response (ASSR) detection. In conventional ORD methods, the statistical tests are applied at the end of data collection ('single-shot tests'). In sequential ORD methods, statistical tests are applied repeatedly, while data is being collected. However, repeated testing can increase False Positive (FP) rates. One solution is to infer that response is present only after the test remains significant for a predefined number of consecutive detections (NCD). Thus, this paper describes a new method for finding the required NCD that control the FP rate for ASSR detection.Design: NCD values are estimated using Monte Carlo simulations.Study sample: ASSR signals were recorded from 8 normal-hearing subjects.Results: The exam time was reduced by up to 38.9% compared to the single-shot test with loss of approximately 5% in detection rate. Alternatively, lower gains in time were achieved for a smaller (non-significant) loss in detection rate. The FP rates at the end of the test were kept at the nominal level expected (1%).Conclusion: The sequential test strategy with NCD as the stopping criterion can improve the speed of ASSR detection and prevent higher than expected FP rates.

An Analysis of The Parameters Used In Speech ABR Assessment Protocols.

The aim of this study was to assess the parameters of choice, such as duration, intensity, rate, polarity, number of sweeps, window length, stimulated ear, fundamental frequency, first formant, and second formant, from previously published speech ABR studies. To identify candidate articles, five databases were assessed using the following keyword descriptors: speech ABR, ABR-speech, speech auditory brainstem response, auditory evoked potential to speech, speech-evoked brainstem response, and complex sounds. The search identified 1288 articles published between 2005 and 2015. After filtering the total number of papers according to the inclusion and exclusion criteria, 21 studies were selected. Analyzing the protocol details used in 21 studies suggested that there is no consensus to date on a speech-ABR protocol and that the parameters of analysis used are quite variable between studies. This inhibits the wider generalization and extrapolation of data across languages and studies.

Assessment Tools for Use in Patients with Ménière Disease: An Update.

A number of electrophysiological tests have been proposed for the initial diagnostic assessment or for the follow-up phase of patients affected by Ménière disease. The most common are: (i) vestibular evoked myogenic potentials (VEMPs); (ii) electrocochleography (ECochG); and (iii) otoacoustic emissions (OAEs). This paper presents the latest clinical developments with these 3 testing modalities. The PubMed, Embase, and Cinahl databases were searched from 2006 to December 2016. Full-text articles were obtained in cases where the title, abstract, or key words suggested that the study may be eligible for this review. The medical subject heading (MeSH) terms included the following: Ménière, hearing threshold, vestibule, otoacoustic emissions, inner ear, ECochG, VEMPs. There were 368 identified papers, out of which 87 were eligible for inclusion. Overall the data in the literature are still limited and the recommended procedures have not reached an international consensus. From the available data, one can conclude that none of the electrophysiological tests could be considered as pathognomonic, for the diagnosis of Ménière disease: presently, the tests could be mostly used in a supportive role to the clinical diagnosis. Hopefully, in the future, improved technology in electrophysiological testing could contribute to the development of better strategies for the diagnosis of Ménière disease.

Assessment of Cochlear Trauma During Cochlear Implantation Using Electrocochleography and Cone Beam Computed Tomography.

OBJECTIVE: To assess cochlear trauma during cochlear implantation by electrocochleography (ECoG) and cone beam computed tomography (CBCT) and to correlate intraoperative cochlear trauma with postoperative loss of residual hearing. METHODS: ECoG recordings to tone bursts at 250, 500, 750, and 1000 Hz and click stimuli were recorded before and after insertion of the cochlear implant electrode array, using an extracochlear recording electrode. CBCTs were conducted within 6 weeks after surgery. Changes of intraoperative ECoG recordings and CBCT findings were correlated with postoperative threshold shifts in pure-tone audiograms. RESULTS: Fourteen subjects were included. In three subjects a decrease of low-frequency ECoG responses at 250, 500, 750, and 1000 Hz occurred after insertion of the electrode array. This was associated with no or minimal residual hearing 4 weeks after surgery. ECoG responses to click stimuli were present in six subjects and showed a decrease after insertion of the electrode array in three. This was associated with a mean hearing loss of 21 dB in postoperative pure-tone audiograms. Scalar dislocation of the electrode array was assumed in one subject because of CBCT findings and correlated with a decrease of low-frequency ECoG responses and a complete loss of residual hearing. CONCLUSION: Hearing loss of ≤11 dB is not associated with detectable decrease in ECoG recordings during cochlear implantation. However, in a majority of patients with threshold shifts of >11 dB or complete hearing loss, an intraoperative decrease of high- or low-frequency ECoG signals occurs, suggesting acute cochlear trauma.

Refining the audiological assessment in children using narrow-band CE-Chirp-evoked auditory steady state responses.

OBJECTIVE: To demonstrate the feasibility and reliability of simultaneous binaural recording of auditory steady-state responses (ASSR) in young children using narrow-band CE-Chirps as stimuli. DESIGN: Prospective cohort study comparing ASSR thresholds to four frequency stimuli (0.5, 1, 2, and 4 kHz), with click-evoked auditory brainstem responses (ABR) and behavioral response audiometry. STUDY SAMPLE: Thirty-two young children (mean age 7.4 ± 5.2 months) referred for auditory assessment were evaluated. RESULTS: The mean duration for ABR recordings was 13.3 ± 7.2 min versus 22.9 ± 15.8 min for ASSR (p < 0.01). ASSR (means of 2 and 4 kHz thresholds) were highly correlated with ABR thresholds (R2 = 0.935, p < 0.001), though significantly different (3 ± 10.7 dB, p = 0.02). ASSR (means of 0.5, 1, 2, and 4 kHz thresholds) were highly correlated with mean behavioral response audiometry thresholds (R2 = 0.968, p < 0.001). ASSRs were highly and significantly correlated with behavioral response audiometry at 0.5, 1, 2, and 4 kHz (R2 = 0.845, 0.907, 0.929, and 0.859 respectively, p < 0.001). 87.5% and 90.7% ASSR thresholds were within a ± 10 dB range around their corresponding ABR and mean behavioral response audiometry thresholds. CONCLUSIONS: Narrow-band CE-Chirps allow a fast and reliable assessment of auditory thresholds in children, especially in the low-frequency range, by comparison with other stimuli.

A low cost setup for behavioral audiometry in rodents.

In auditory animal research it is crucial to have precise information about basic hearing parameters of the animal subjects that are involved in the experiments. Such parameters may be physiological response characteristics of the auditory pathway, e.g. via brainstem audiometry (BERA). But these methods allow only indirect and uncertain extrapolations about the auditory percept that corresponds to these physiological parameters. To assess the perceptual level of hearing, behavioral methods have to be used. A potential problem with the use of behavioral methods for the description of perception in animal models is the fact that most of these methods involve some kind of learning paradigm before the subjects can be behaviorally tested, e.g. animals may have to learn to press a lever in response to a sound. As these learning paradigms change perception itself (1,2) they consequently will influence any result about perception obtained with these methods and therefore have to be interpreted with caution. Exceptions are paradigms that make use of reflex responses, because here no learning paradigms have to be carried out prior to perceptual testing. One such reflex response is the acoustic startle response (ASR) that can highly reproducibly be elicited with unexpected loud sounds in naïve animals. This ASR in turn can be influenced by preceding sounds depending on the perceptibility of this preceding stimulus: Sounds well above hearing threshold will completely inhibit the amplitude of the ASR; sounds close to threshold will only slightly inhibit the ASR. This phenomenon is called pre-pulse inhibition (PPI) (3,4), and the amount of PPI on the ASR gradually depends on the perceptibility of the pre-pulse. PPI of the ASR is therefore well suited to determine behavioral audiograms in naïve, non-trained animals, to determine hearing impairments or even to detect possible subjective tinnitus percepts in these animals. In this paper we demonstrate the use of this method in a rodent model (cf. also ref. (5)), the Mongolian gerbil (Meriones unguiculatus), which is a well know model species for startle response research within the normal human hearing range (e.g. (6)).

Assessment of the central hearing system of sport divers.

OBJECTIVE: To investigate the effect of regular scuba diving on central processing sequences of sport divers who have no history of noise exposure or ear-related accidents using a comprehensive topographic examination of the central hearing system. DESIGN: Cross-sectional controlled comparison study. SETTINGS: General sports diving community. PARTICIPANTS: 81 sport divers with a mean of 300 dives each were compared with a control group of 81 non-divers. MAIN OUTCOME MEASURE: The participants were classified into three age groups. Hearing test results were combined for both ears. Examination included brainstem evoked response audiometry (BERA), cortical evoked response audiometry (CERA) and dichotic listening tests to screen for retrocochlear and central hearing disorders. Testing of brainstem latencies was performed in a gender-dependent manner. RESULTS: BERA showed a pathological extension of the I-V-latency in one diver. Magnetic tomographic imaging ruled out brainstem lesions. No reason for the measured latency could be detected. All other latencies (I-III, III-V and I-V) in both gender groups were within normal limits. No statistically significant differences between divers and non-divers could be detected. Dichotic listening showed no clinical abnormalities in any of the participants, but in the age group 18-29 years divers performed significantly better than non-divers (p = 0.01). CERA revealed no significant differences between divers and non-divers in the age group 18-29 years and 30-39 years, whereas divers in the age group 41-50 demonstrated significantly better test results (p = 0.045) (difference of the means: 4.18 dB). CONCLUSION: Dichotic listening and CERA did not reveal a significant reduction of central hearing performance in divers. Persistent on-shore BERA wave latency prolongations that were present in one study could not be confirmed in our study group. This first comprehensive topographic examination of the central hearing system of divers showed no abnormalities.

[Subjective intraoperative hearing self-assessment in patients after stapedotomy comparing to postoperative pure-tone audiometry]. / Subiektywna sródoperacyjna poprawa sluchu u chorych po stapedotomiach w porównaniu z wynikiem kontrolnego badania sluchu w audiometrii tonalnej progowej.

UNLABELLED: In otosclerosis patients the most common procedure followed at Otosurgical Dept. Medical University of Lodz is stapedotomy with insertion of teflon-piston prosthesis. When surgery is finished a whisper hearing test is done from the 1 meter distance for brief intraoperative hearing improvement assessment. There is a number of patient who report subjective intraoperative hearing improvement which is not confirmed by postoperative pure-tone audiometry (2-3rd post-op day). THE AIM OF THE STUDY: was the analysis of factors influencing stapedotomy (teflon-piston procedure) patients in which intraoperative hearing improvement was not confirmed by postoperative pure-tone audiometry. MATERIAL AND METHOD: Retrospective analysis of postoperative hearing results in patients who underwent stapedotomy (teflon-piston operation) at the Otosurgical Dept. Medical University of Lodz from 2005 to 2009. RESULTS: The total number of 142 stapedotomies were analyzed. In 27 ears no hearing improvement was reported (19.1%). Among them 18 reported intraoperative hearing improvement not confirmed on postoperative pure-tone audiometry and 9 cases intraopertively reported no hearing improvement. Patients in Group A (hearing improvement 1-2 month post stapedotomy)--12 cases (44.4%) with hearing improvement confirmed by pure-tone audiometry and Group B--5 cases (55.6%) in which no sign of hearing improvement in pure-tone audiometry was reported. CONCLUSION: In patients who intraopertively reported hearing improvement not supported by the pure-tone audiometry the following factors seem to play a vital role: a) strong suggestion and willingness of improvement after surgical treatment, b) specific condition of the whisper hearing test at the operating room environment, c) patient's stress during the surgery and strong fear of possible revision surgery.

The choice of distracting task can affect the quality of auditory evoked potentials recorded for clinical assessment.

Auditory evoked potential (AEP) recordings often require subjects to ignore the stimuli and stay awake. In the present experiment, early (ABR), middle (MLR), and late latency (LLR) AEPs were recorded to compare the effect of five different distracting tasks: (1) doing nothing eyes open, (2) reading, (3) watching a movie, (4) solving a three-digit sum, and (5) doing nothing eyes closed (or counting the stimuli for LLR). Results showed that neither the amplitudes nor the latencies of the ABR, MLR, or LLR were affected by task. However, the amount of pre-stimulus activity (noise) or amplitude rejection was significantly and differently affected by the distracting task. For the ABR, the math task was the noisiest but, for the MLR, the amount of noise was greater when watching a movie. As for the LLR, reading and watching a movie yielded the lowest percentage of rejected traces. In conclusion, the choice of distracting task depends on the AEP being measured and should be chosen to improve the quality of the AEP traces and thus reduce recording time.

Initial audiologic assessment of infants referred from well baby, special care, and neonatal intensive care unit nurseries.

PURPOSE: The purpose of the study was to evaluate the effectiveness of a 2-hr initial audiologic assessment appointment for infants referred from area universal newborn hearing screening (UNHS) programs to a clinical audiology department in an urban hospital. METHOD: A prospective auditory brainstem response (ABR)-based protocol, including clicks, frequency-specific tone bursts, and bone-conducted stimuli, was administered by 10 audiologists to 375 infants. Depending on the ABR findings, additional test options included distortion product otoacoustic emissions (DPOAEs), high-frequency tympanometry, and/or otologic examination. RESULTS: In 88% of the 2-hr test sessions, at least 4 ABR threshold estimates were obtained (i.e., bilateral clicks and either a 500- or 1000-Hz tone burst and a 4000-Hz frequency tone burst for the better ear). The incidence of hearing loss was significantly different across nursery levels: 18% for Level I (well baby), 29% for Level II (special care), and 52% for Level III (neonatal intensive care unit). Hearing loss type was defined at the initial assessment for 35 of the 51 infants with bilateral hearing loss based on bone-conduction ABR, latency measures, DPOAEs, high-frequency tympanometry, and/or otologic examination. CONCLUSIONS: Our findings indicate that a 2-hr test appointment is appropriate for all nursery levels to diagnose severity and type of hearing loss in the majority of infants referred from UNHS. Examination by an otolaryngologist within 24-48 hr further defines the hearing loss and facilitates treatment plans.

Periodogram based tests for distortion product otoacoustic emissions.

Distortion product otoacoustic emissions (DPOAEs) are an important nonbehavioral measure of cochlear function, which provides a close analogue of the behavioral pure-tone audiogram. DPOAEs are sinusoidal distortion products (DPs) produced by nonlinearities in the healthy cochlea. Detection of DPs is accomplished in the Fourier domain with a periodogram based test. The test compares the power in the DP periodogram bin to a noise estimate derived from a certain number of the surrounding bins. Statistical properties of this test to date have only been examined by constructing receiver operator characteristics curves derived from DPOAE measurements in normal and hearing impaired individuals. In this paper the null distribution of this order-statistic based test is explicitly derived, and via simulations intended to mimic the nonwhite features of real-ear noise measurements, the power of the test is demonstrated. These simulations demonstrate that a local F test is more powerful than this DPOAE test, with critical values that are easier to calculate. Although the power of both tests increase with an increasing number of bins, the improvement is negligible at around four bins. Since the power of both tests decrease at lower DP frequencies, it is not recommended to use a large number of bins.

Assessment of medial olivocochlear system function in pre-term and full-term newborns using a rapid test of transient otoacoustic emissions.

This study was conducted to investigate maturation of the medial olivocochlear efferent system (MOCS) in pre- and full-term neonates using Quickscreen (Otodynamics Ltd) and to confirm previous findings on transient otoacoustic emission (TEOAE) suppression in neonates. MOCS maturation was investigated in 46 neonates born at the Chaim Sheba Medical Center, Tel Hashomer, Israel, using Quickscreen. All neonates were normal with no family history of general or auditory disease and no risk factors for hearing impairment. MOCS function appears gradually in human pre-term neonates and is considered to reach maturity shortly after term birth. The clinical value of MOCS testing in specific populations of newborns at risk for hearing and/or brainstem function can be legitimately raised as activation of the MOCS clearly alters cochlear output. The present results can be interpreted to support the testing of infants at risk of developing abnormal MOCS function using a commercially available rapid TEOAE measurement system.

Hearing assessment by recording multiple auditory steady-state responses: the influence of test duration.

The influence of test duration on the precision of hearing thresholds estimated by recording multiple auditory steady-state responses (ASSRs) was investigated. ASSR thresholds at four frequencies in both ears were assessed in 10 normal-hearing and 10 hearing-impaired subjects. The precision of the estimated hearing thresholds was compared for ASSR recordings of 5, 10 and 15 min per intensity level, corresponding to total test durations of approximately 30, 55 and 70 min for hearing-impaired ears. Furthermore, an intensity step size of 10 dB was compared to a step size of 5 dB. The mean difference scores averaged over the four frequencies were 15 +/- 10, 12 +/- 9 and 11 +/- 8 dB after recordings of 5, 10 and 15 min respectively. The corresponding Pearson correlation coefficients were 0.93, 0.95 and 0.96. Increasing the length of the separate recordings increases the precision of the estimates, independent of tested frequency. A compromise between both will have to be made. With a total test duration of approximately 1 h, four hearing thresholds in both ears can be estimated with a standard error of the estimate of 8 dB.

A implementação de programa de triagen auditiva neonatal universal em um hospital universitário brasileiro / Universak newborn hearing screeening program assessment in a Brazilian university

Objetivo: avaliar os resultados de implementação do Programa de Triagem Auditiva Neonatal Universal (PT aNU) no Hospital Universitário da Universidade de São Paulo (HU-USP), São Paulo, SP. Casuística e Métodos: Programaou-se a avaliação universal por triagem auditiva...

Cost comparison of auditory brainstem response versus magnetic resonance imaging screening of acoustic neuroma.

The cost-effectiveness of current diagnostic approaches employed in patients with suspected acoustic neuroma was evaluated. Currently, patients with signs and symptoms suggestive of acoustic neuroma, such as sudden unilateral hearing loss and/or tinnitus, undergo auditory brainstem response (ABR) screening tests to rule out this condition. If the ABR is normal, acoustic neuroma can be ruled out. However, if the ABR is abnormal, magnetic resonance imaging (MRI) or computed tomography is necessary to confirm the diagnosis. When one considers the total costs of this screening approach, one can ask whether straight MRI screening of all of these patients would be a more cost-effective approach to diagnosing this condition. A retrospective chart review of patient records obtained from the acoustic diagnostics laboratory at Hotel Dieu Hospital, Kingston, Ontario, was performed. A database of patients who have undergone ABR testing over the past 2 years was compiled and analyzed to assess how many of them went on to receive MRI. The total costs (based on Ontario Health Insurance Plan [OHIP] fee schedule rates) of this approach were compared with the estimated costs of straight MRI screening performed on the same patient population. By making such an analysis, decisions regarding the most cost-effective approach to screening for acoustic neuroma can be objectively assessed.

Cost-effective diagnosis of acoustic neuromas: a philosophical, macroeconomic, and technological decision.

OBJECTIVE: Our goals were to define the most sensitive techniques of acoustic neuroma diagnosis, to examine their relative costs, and to propose diagnostic modality selection given the rarity of acoustic neuroma incidence and given the other costs that society faces in more commonly encountered diseases. METHODS: We conducted a MEDLINE search of the English language from 1966 to 2001 using the following keywords: acoustic neuroma, acoustic tumor, vestibular schwannoma, diagnosis, cost effectiveness, MRI, auditory brainstem response, brainstem audiometric evoked response, incidence, and prevalence. RESULTS: Although magnetic resonance imaging with gadolinium remains the most sensitive diagnostic modality in the discovery of acoustic neuromas, its cost may be prohibitive for some societies. CONCLUSION: Which modality to use in acoustic neuroma diagnosis is just as much a philosophical and macroeconomic question as a technological one. CLINICAL SIGNIFICANCE: The cost of a timely diagnosis of acoustic neuromas must be weighed against using resources for other, more pressing, health concerns.

[Assessment of transient evoked otoacoustic emission (TEOAE) in preterm newborns with low birth weight]. / Badanie wplywu krótkiego czasu trwania ciazy i niskiej masy urodzeniowej noworodków na wystepowanie emisji otoakustycznej wywolanej trzaskiem (TEOAE).

Transient evoked otoacoustic emission (TEOAE) is accepted as a good and universal test for screening of the cochlea function in newborns. This method is particularly useful in the newborn group with risk-factors of hearing losses. Early identification of the cochlear pathology gives possibility of supplying with hearing aid and rehabilitation. In this study 300 newborns were tested with TEOAE, especially patients whose birth weight was below 1500 g and were born preterm--below 33 hbd. The study did not indicate any tendency of changing TEOAE in newborns with hypotrophy. Hypotrophy does not seem to influence the cochlea function monitored by TEOAE analysis.

A audiometria tonal liminar e/ou avaliação instrumental confirmam posteriormente a audiometria de tronco cerebral obtida precocemente em crianças deficientes atuditivas? / Does Pure Tone Threshold Audiometry and/or Behavorial Auditory Assessment Confirm Subsequent Response Obtained Precociously in Children with Auditive Deficiency?

Esta pesquisa foi realizada a partir do levantamento dos diagnósticos audiológicos obtidos através da audiometria de tronco cerebral (ATC), realizada precocemente, e da audiometria tonal liminar (ATO e/ou avaliação instrumental (AI), realizadas anos depois nas mesmas 30 crianças com deficiência auditiva em atendimento no setor de Audiologia Educacional do Serviço de Atendimento Fonoaudiológico da Universidade Federal de Santa Maria, com o objetivo de compara-loa e verificar a concordância existente entre eles. Resultados: A comparação, levando em conta os graus de perda auditiva obtidos através dos três procedimentos de avaliação considerados, mostrou uma concordância de 97,30% dos diagnósticos nas perdas auditivas de grau profundo, 77,78% no grau severo, 57,15% no grau moderado e de 33,33% no grau moderadamente-severo. No geral, do ponto de vista clínico, verificou-se concordância diagnóstica em 57 (95,00%) das 60 orelhas pesquisadas.

This research was made after survey of the audiologics diagnostics obtained through of the auditory brainstem response (ABR), pure tone threshold audiometry (PTA) and/or behavioral auditory assessment (BAA) made in 30 children with auditive deficiency with the purpose of to compare and Check the agreement between them. Results: In the comparison of the diagnostics of the grades of hearing loss obtained watched a agreement of 97,30% of the diagnostics in the hearing losses of profound grade, 77,78% in the severe grade, 57,15% in the moderate grade and 33,33% in the moderately-severe; in general, of the clinical point of view, watched diagnostic agreement in 57 (95,00%) of the 60 ears researched.