Patient and Device Factors Contributing to Electrically Evoked Stapedial Reflex Thresholds in Cochlear Implanted Adults.

INTRODUCTION: Optimal cochlear implant (CI) outcomes are due to, at least in part, appropriate device programming. Objective measures, such as electrically evoked stapedial reflex thresholds (ESRTs), can be used to more accurately set programming levels. However, underlying factors that contribute to ESRT levels are not well understood. The objective of the current study was to analyze how demographic variables of patient sex and age, along with CI electrode location, influence ESRTs in adult CI recipients. METHODS: A single institution retrospective review was performed. Electronic medical records, CI programming records, and clinic database of postoperative computerized tomography were reviewed to gather information regarding patient demographics, ESRTs, and electrode array metrics including medial-lateral distance and scalar location. Linear mixed models were constructed to determine how demographic variables and electrode position influence ESRTs recorded in 138 adult CI recipients. RESULTS: ESRTs were significantly affected by recipient age, with older listeners demonstrating higher ESRT levels. On average, males had higher ESRT levels when compared to females. In a subset of the study sample, ESRT levels increased with increasing medial-lateral distance; however, there was not a statistically significant effect of electrode type (lateral/straight arrays compared to perimodiolar arrays). ESRTs were not affected by scalar location. DISCUSSION/CONCLUSIONS: The results suggest that key demographic and electrode position characteristics influence the level of ESRTs in adult CI recipients. While ESRTs are widely used to assist with CI programming, underlying factors are not well understood. The significant factors of aging and sex could be due to middle ear mechanics or neural health differences. However, further data are needed to better understand these associations.

Stapedial Reflex: A Possible Novel Biomarker of Early Bulbar Involvement in Amyotrophic Lateral Sclerosis Patients.

BACKGROUND AND AIM: Amyotrophic lateral sclerosis (ALS) is a neuromuscular progressive disorder, characterized by limb and bulbar muscle wasting and weakness. 30% of patients present a bulbar onset, while 70% a spinal outbreak, although most of them develop bulbar impairment later on. Due to the lack of an early biomarker of bulbar involvement, we chose to evaluate the role of stapedial reflex (SR) in order to predict preclinical bulbar impairment in ALS. MATERIALS AND METHODS: We enrolled 36 ALS patients. We assessed revised-ALS functional-rating-scale and SR for a total of 4 visits. We established the presence of SR, acoustic reflex latency test (ARLT), and SRs Decay. Patients who had not develop bulbar signs at fourth visit continued follow-up up to 15 months. Data were analyzed by using Mann-Whitney U test, Friedman test, and Cox regression analysis. RESULTS: We observed that SRs Decay at 500 and 1,000 Hz is the first parameter of SR to get altered in all ALS patients before the development of bulbar impairment. Twenty-eight patients developed bulbar impairment during the study. We highlighted a correlation between the progression rate of disease and both time of SRs Decay alteration and time of bulbar impairment from disease onset. Four patients who did not develop bulbar impairment had a progression rate lower than the other ones (p < 0.05). DISCUSSION AND CONCLUSIONS: This study shows that SR Decay test could be a sensitive measure for detecting pre-symptomatic bulbar involvement in ALS and could represent a simple, noninvasive, and useful biomarker of disease progression.

Stapedial reflex threshold predicts individual loudness tolerance for people with autistic spectrum disorders.

People with autism spectrum disorder (ASD) frequently show the symptoms of oversensitivity to sound (hyperacusis). Although the previous studies have investigated methods for quantifying hyperacusis in ASD, appropriate physiological signs for quantifying hyperacusis in ASD remain poorly understood. Here, we investigated the relationship of loudness tolerance with the threshold of the stapedial reflex and with contralateral suppression of the distortion product otoacoustic emissions, which has been suggested to be related to hyperacusis in people without ASD. We tested an ASD group and a neurotypical group. The results revealed that only the stapedial reflex threshold was significantly correlated with loudness tolerance in both groups. In addition to reduced loudness tolerance, people with lower stapedial reflex thresholds also exhibited higher scores on the Social Responsiveness Scale-2.

[General anesthesia influence on cochlear implant intraoperative testing]. / Vliianie obshchei anestezii na rezul'taty intraoperatsionnogo testirovaniia kokhlearnogo implanta.

In this article, we consider the influence of combined general anesthesia on the results of electrically-involved stapedial reflex threshold (esrt) registration. We pay a special attention to the anesthesia to exclude its influence on the esrt. This study included 52 patients with bilateral chronic neurosensory hearing impairment. We conducted a retrospective (from 2014 to 2016) and prospective (from 2017 to 2018) analysis of anesthesia protocols. Even though the inhaled anesthesia (sevoflurane in this case) has a depressive effect on esrt registration (the higher the minimal alveolar concentration of anesthetic agent, the higher the reflex threshold), our study shows a possibility of using it in an extended anesthesia monitoring. Inclusion of myorelaxants in cochlear implantation anesthesia protocol not only provides a safe anesthesia, but also does not prevent a timely intraoperative cochlear implant testing.

Evaluation of volatile and intravenous anesthetics, effects on the threshold of neuroresponse telemetry and the threshold of acoustically evoked stapedial reflex in children undergoing cochlear implant surgery.

BACKGROUND AND AIMS: Congenital hearing loss affects about 1 in every 1000 live births. Cochlear implant is an effective therapeutic method for aural rehabilitation in children suffering from severe-to-profound hearing loss. The aim of this study was to compare the effects of the intravenous and inhalational anesthesia techniques on neuroauditory threshold and stapedial reflex threshold responses. MATERIAL AND METHODS: After approval of the university ethics committee and obtaining written informed parental consent, 110 children with severe or profound bilateral sensorineural hearing loss undergoing cochlear implant surgery were randomly divided in two groups. The effects of the total intravenous anesthesia (propofol and remifentanil) and inhalation anesthesia (sevoflurane) techniques were evaluated on the neuroauditory threshold and stapedial reflex threshold responses of patients. Variations in systolic and diastolic blood pressures and mean arterial blood pressure were measured in both groups. RESULTS: No significant difference was observed in the following parameters: age, weight, duration of anesthesia, and surgery. No side effects was observed in the two groups. No significant difference was found in the Telemetry Neuroal Response Test (TNRT) reflex between the two groups (P = 0.294); however, the difference between the two groups was significant (P = 0.001) for Electrical Stapedial Reflex Threshold (ESRT) reflex. In the sevoflurane group, in 39 patients in the electrode 3 and in 17 patients in the electrode 9 (compared with 20 and 6 patients in the Propofol-remifentanil group) complete suppression of stapedial reflex existed. CONCLUSION: Our results suggest that, during the cochlear implant surgery, use of inhalation anesthetics should be avoided for achieving controlled hypotension because this may suppress or even fully eliminate stapedial reflex. Remifentanil and Propofol infusion has a slight effect on hearing thresholds and is recommended for determining hearing thresholds during cochlear implant surgeries.

Acoustic reflex patterns in amyotrophic lateral sclerosis.

The aim of the study is to investigate acoustic reflex testing in amyotrophic lateral sclerosis patients. Amplitude, latency, and rise time of stapedial reflex were recorded for 500 and 1000 Hz contralateral stimulus. Statistical analysis was performed by the Wilcoxon test and the level of significance was set at 5 %. Fifty-one amyotrophic lateral sclerosis patients and ten sex- and age-matched control subjects were studied. Patients were further divided in two groups: amyotrophic lateral sclerosis-bulbar (38 cases, with bulbar signs at evaluation) and amyotrophic lateral sclerosis-spinal (13 cases, without bulbar signs at evaluation). Stapedial reflex was present in all patients. There was a statistically significant difference in the mean amplitude, latency, and rise time between the amyotrophic lateral sclerosis patients as compared with the controls. Amplitude was lower in both the amyotrophic lateral sclerosis-bulbar and the amyotrophic lateral sclerosis-spinal patients than in the controls (p < 0.05) and rise time was longer in both patient groups compared with the controls (p < 0.05). These results confirm the presence of abnormal acoustic reflex patterns in amyotrophic lateral sclerosis cases with bulbar signs and, moreover, suggesting a possible subclinical involvement of the stapedial motor neuron even in amyotrophic lateral sclerosis-spinal patients. Amplitude and rise time seem to be good sensitive parameters for investigating subclinical bulbar involvement.

Audiological evaluation in children affected by myelomeningocele.

PURPOSE: The aim of the present study is to evaluate the auditory system in children affected by myelomeningocele and comparing the results with clinical neurological conditions. MATERIALS AND METHODS: Forty-three children, aged between 7 and 26 years, affected by myelomeningocele were investigated by means of subjective tonal audiometry and objective impedance audiometry (tympanometry and acoustic stapedial reflex). RESULTS: Audiological evaluation showed an alteration in 32 patients (74%%). Nine patients presented a mild hearing loss: bilateral in six cases (three sensorineural, one mixed, and two conductive) and unilateral in three cases (two mixed and one conductive). One patient had moderate unilateral conductive deafness and, finally another one severe unilateral sensorineural. Almost all patients with deafness were affected by myelomeningocele and Chiari II. Stapedial-cochlear reflex investigation showed an alteration in 30 patients (70%): 9 of these also showed deafness while the remaining 21 was normal hearing. In these 30 patients, we demonstrated the presence of myelomeningocele, hydrocephalus, and Chiari II malformation in 21 subjects (70%). CONCLUSION: Otoneurological evaluation is important in myelomeningocele not only at the birth but also in the follow-up. It could have an important prognostic role for neurological impairment.

Electrically evoked stapedial reflex threshold and behavioral method usefulness in the cochlear implant programming in pediatric population.

OBJETIVE: To determine the utility of the electrically evoked stapedial reflex test (ESRT) and behavioral method in the CIs programming as an objective method to identify MCL levels in the CIs programming in pediatric patients. METHOD: Cross-sectional cohort study that included 20 pediatric patients with postlingual deafness and CI unilateral. They were performed clinical history, tympanometry, ESRT and by free field audiometry, before and after programming modifications according to MCL levels obtained by ESRT were performed. ESRT threshold was assessed with individual 300 ms stimuli on the 12 electrodes and recorded through manual decay. Likewise, the maximum comfort threshold (MCL) of each electrode was obtained through a behavioral analysis. RESULTS: No significant differences were found between the ESRT and behavioral method in MCLs levels in each of the electrodes evaluated. In addition, the correlation coefficients were significant and located in a range of 0.55-0.81, higher in electrodes 7, 8, and 9 (r = 0.77, 0.76, and 0.81, respectively). However, the median hearing threshold established by the ESRT was significantly lower compared to the behavioral threshold (36.0 vs. 47.0 dB, p < 0.0001), regardless of age (p = 0.249) or the etiology of hearing loss (p = 0.292). The difference between the tests was in the number of times to do it, the ESRT was done once and the behavioral on average 4 ± 1 times. CONCLUSION: Similar MCL thresholds were obtained in both ESRT and behavioral test, establishing that both methods are reliable for use in pediatric patients; however, ESRT allows shortening the time to achieve normal hearing and language acquisition thresholds in a more optimal time.

The effect of cochlear implant age and duration of intervention on ESRT in children with cochlear implant.

OBJECTIVE: To study the effect of cochlear implant age and duration of the intervention (auditory rehabilitation post-cochlear implantation) on ESRT in children with cochlear implants. METHODS: A total of 90 pre-lingual cochlear implant users were included. For the measurement of ESRTs the recipient's processor was connected to the programming pod and electrode numbers 22, 11 and 3 (apical, middle and basal), respectively, were activated to give stimulation sequentially and elicit deflection as a response. RESULTS: There were significant differences in the measured T, C and ESRT levels with respect to the duration of the intervention (auditory rehabilitation post-cochlear implantation) and cochlear implant age obtained at p < 0.05*, 0.01**. DISCUSSION: The differences in the T, C and ESRT levels after continued device usage and after attending auditory rehabilitation sessions post-cochlear implantation are subjected to optimal benefit from implantation during the critical period. CONCLUSION: The differences in T, C and ESRT levels can be utilised clinically to study the importance of duration of cochlear implant device usage and the importance of auditory rehabilitation post-cochlear implantation in children with cochlear implantation.

The Potential Significance of Reversed Stapes Reflex in Clinical Practice in Idiopathic Intracranial Hypertension.

Background: Stapes reflex test is a method of evaluating the involuntary muscle contraction of the stapedius muscle in response to a high-intensity sound stimulus. The formation of this reflex involves the intact function of the 7th nerve, brain stem, 8th nerve, and middle ear. Due to ease of administration and information yielded, the stapedial reflex is considered one of the most powerful differential diagnostic audiological procedures. Numerous studies have remarked on the fluid communication between the intracochlear and intracranial spaces through the cochlear aqueduct. Currently, the potential significance of a noninvasive audiological technique in the discrimination of raised intracranial pressure constitutes a crucial topic of interest. Methods: We have performed the pre-LP and post-LP detailed otorhinolaryngological investigations, including the detailed inspection, audiometric testing, tympanometry, and stapedial reflex in a total of four consecutive patients with IIH. Results: We found that the stapedial reflex was bilateral absent initially in two of the patients. However, the second stapedial reflex investigations after LP showed reversal of the reflex responses in both of the patients. Conclusions: We suggest some hypotheses and propose some clinical applications. Future studies focusing on the potential utility of this reflex in the monitorization of IIH may provide crucial perspectives.

Transient decrease in sound tolerance levels following hearing deprivation in normal-hearing subjects.

Objective: To determine the circadian influence on sound sensitivity produced by temporal hearing deprivation in healthy normal human subjects. Design: Participants underwent bilateral earplugging before completion of anthropometry, the author's developed questionnaire, the Hamilton Anxiety and Depression Inventory, pure tone audiometry (PTA), stapedial reflex thresholds (SRT), distortion products otoacoustic emissions input/output (DPOAE-I/O), and uncomfortable loudness levels (ULLs). Afterward, the participants were randomly divided into group A, starting at 8:00 a.m. and finishing at 8:00 p.m., and group B, starting at 4:00 p.m. and ending at 4:00 a.m. Serum cortisol levels and audiological test results were obtained at the beginning and end of the session and 24-h free urinary cortisol levels were measured. Study sample: Thirty healthy volunteers. Results: PTA was 2.68 and 3.33 dB HL in groups A and B, respectively, with no statistical difference between them. ULLs were significantly lower in group A compared to group B, with an average of 8.1 dB SPL in group A and 3.3 dB SPL in group B (p < 0.0001). A SRT shift was observed in group A, with no difference in group B, and a night shift in DPOAE-I/O in group B. Conclusions: Reduced loudness tolerance is demonstrated during daytime hearing deprivation in contrast to nighttime; this may be due to increased central gain in the awake cortex.

Twist and turn into chronic disorders of consciousness: Potential role of the auditory stapedial reflex.

BACKGROUND: Patients suffering from chronic disorders of consciousness (DOC), including minimally conscious state (MCS) and unresponsive wakefulness syndrome (UWS), typically show an awareness impairment paralleled by a significant reflex hyper-excitability, which depend on the cortical deafferentation following brain-damage-induced thalamocortical system deterioration. Nonetheless, recent studies have shown a residual preservation of cortico-subcortical pathways that may sustain residual fragments of awareness in some DOC patients. OBJECTIVE: The aim of our study was to assess whether the cortical modulation of auditory stapedial reflex (ASR) could be a marker of a higher degree of brain network connectivity, which is a fundamental prerequisite for awareness generation and maintenance. METHODS: We applied a repetitive transcranial magnetic stimulation (rTMS) protocol over the primary auditory area and measured the neuromodulation effects on ASR threshold (ASRt) in a DOC sample and a healthy control group (HC). RESULTS: We observed an ASRt reduction in all the HC and MCS individuals, in parallel to a better sound-induced motor responsiveness in MCS sample, while all the UWS patients, but two, did not show any significant ASRt modulation. CONCLUSION: We hypothesize that our conditioning protocol may have entrained and potentiated some spared cortico-subcortical networks that sustained the clinical and electrophysiological amelioration we found. Our data electrophysiologically demonstrate for the first time that primary the auditory area can influence ASR elicitation, and such finding may support the DOC differential diagnosis.

Time-varying auditory gain control in response to double-pulse stimuli in harbour porpoises is not mediated by a stapedial reflex.

Echolocating animals reduce their output level and hearing sensitivity with decreasing echo delays, presumably to stabilize the perceived echo intensity during target approaches. In bats, this variation in hearing sensitivity is formed by a call-induced stapedial reflex that tapers off over time after the call. Here, we test the hypothesis that a similar mechanism exists in toothed whales by subjecting a trained harbour porpoise to a series of double sound pulses varying in delay and frequency, while measuring the magnitudes of the evoked auditory brainstem responses (ABRs). We find that the recovery of the ABR to the second pulse is frequency dependent, and that a stapedial reflex therefore cannot account for the reduced hearing sensitivity at short pulse delays. We propose that toothed whale auditory time-varying gain control during echolocation is not enabled by the middle ear as in bats, but rather by frequency-dependent mechanisms such as forward masking and perhaps higher-order control of efferent feedback to the outer hair cells.

Pressurized Wideband Acoustic Stapedial Reflex Thresholds: Normal Development and Relationships to Auditory Function in Infants.

This study analyzed effects of pressurization on wideband acoustic stapedial-muscle reflex (ASR) tests in infants cared for in normal newborn (NN) and neonatal intensive care units (NICU). Effects of hearing-screening outcomes on ASR threshold measurements were also evaluated, and a subsequent longitudinal study established normative threshold ranges over the first year after birth. An initial experiment compared thresholds in newborns measured at ambient pressure in the ear canal and at the tympanometric peak pressure. ASR thresholds for broadband noise were higher for ears that did not pass newborn hearing screening and ASR threshold was 14 dB higher for real-ear compared to coupler conditions. Effects of pressurization were significant for ears that passed screening; thus, ASR testing in infants should be conducted at tympanometric peak pressure. ASR threshold was significantly higher for ears that referred on transient evoked otoacoustic emissions and Auditory Brainstem Response (ABR) screening tests and also for ears with conductive and sensorineural hearing loss diagnosed by ABR. Developmental ASR changes were significant over the first year for both normal and NICU infants. Wideband pressurized ASR thresholds are a clinically relevant measure of newborn hearing screening and diagnostic outcomes.

Weak Middle-Ear-Muscle Reflex in Humans with Noise-Induced Tinnitus and Normal Hearing May Reflect Cochlear Synaptopathy.

Chronic tinnitus is a prevalent hearing disorder, and yet no successful treatments or objective diagnostic tests are currently available. The aim of this study was to investigate the relationship between the presence of tinnitus and the strength of the middle-ear-muscle reflex (MEMR) in humans with normal and near-normal hearing. Clicks were used as test stimuli to obtain a wideband measure of the effect of reflex activation on ear-canal sound pressure. The reflex was elicited using a contralateral broadband noise. The results show that the reflex strength is significantly reduced in individuals with noise-induced continuous tinnitus and normal or near-normal audiometric thresholds compared with no-tinnitus controls. Due to a shallower growth of the reflex strength in the tinnitus group, the difference between the two groups increased with increasing elicitor level. No significant difference in the effect of tinnitus on the strength of the middle-ear muscle reflex was found between males and females. The weaker reflex could not be accounted for by differences in audiometric hearing thresholds between the tinnitus and control groups. Similarity between our findings in humans and the findings of a reduced middle-ear muscle reflex in noise-exposed animals suggests that noise-induced tinnitus in individuals with clinically normal hearing may be a consequence of cochlear synaptopathy, a loss of synaptic connections between inner hair cells (IHCs) in the cochlea and auditory-nerve (AN) fibers that has been termed hidden hearing loss.

[The application of acoustic stapedial reflex in hearing screening of infants].

Nowadays,the newborn hearing screening has carried out in China generally.Acoustic stapedial reflex,which could detect problems in the stapedial reflex pathway,is one of the general screening tools.Because of the immatureness of hearing system and poor cooperation of infants,we should build new standards of infants when testing acoustic stapedial reflex.The paper has summarized the studies about acoustic stapedial reflex on infants,which may guide the clinical work.

Membrane fluidity does not explain how solvents act on the middle-ear reflex.

Some volatile aromatic solvents have similar or opposite effects to anesthetics in the central nervous system. Like for anesthetics, the mechanisms of action involved are currently the subject of debate. This paper presents an in vivo study to determine whether direct binding or effects on membrane fluidity best explain how solvents counterbalance anesthesia's depression of the middle-ear reflex (MER). Rats were anesthetized with a mixture of ketamine and xylazine while also exposed to solvent vapors (toluene, ethylbenzene, or one of the three xylene isomers) and the amplitude of their MER was monitored. The depth of anesthesia was standardized based on the magnitude of the contraction of the muscles involved in the MER, determined by measuring cubic distortion product oto-acoustic emissions (DPOAEs) while triggering the bilateral reflex with contralateral acoustic stimulation. The effects of the aromatic solvents were quantified based on variations in the amplitude of the DPOAEs. The amplitude of the alteration to the MER measured in anesthetized rats did not correlate with solvent lipophilocity (as indicated by logKow values). Results obtained with the three xylene isomers indicated that the positions of two methyl groups around the benzene ring played a determinant role in solvent/neuronal cell interaction. Additionally, Solid-state Nuclear Magnetic Resonance (NMR) spectra for brain microsomes confirmed that brain lipid fluidity was unaffected by solvent exposure, even after three days (6h/day) at an extremely high concentration (3000ppm). Therefore, aromatic solvents appear to act directly on the neuroreceptors involved in the acoustic reflex circuit, rather than on membrane fluidity. The affinity of this interaction is determined by stereospecific parameters rather than lipophilocity.

Effect of stylet removal on neural response telemetry and stapedial reflex thresholds during cochlear implantation.

OBJECTIVE: The purpose of this study was to analyze changes in neural response telemetry (NRT) and electrically evoked stapedial reflex thresholds (ESRT) before and after stylet withdrawal during cochlear implant surgery. METHODS: Thirty children (21-92 months old) who were candidates for cochlear implantation took part in this study. In all of them Nucleus Contour Advance was implanted. NRT and ESRT responses were recorded initially with the stylet in and then when the stylet was taken out during the implant procedure. The recordings were performed in the basal, middle, and apical areas of the electrode array. RESULTS: The threshold levels required to obtain NRT and ESRT responses after stylet removal were lower. This decrease was observed in all parts of the cochlea. It was statistically significant in all areas with the exception of the basal ESRT measurements. CONCLUSION: Withdrawing the stylet results in better NRT and ESRT responses, most probably due to a favorable position change of the electrode array within the scala tympani.

Classical Neo-stapedotomy.

Preservation of stapedius muscle and incudo-stapedial joint during stapedotomy for otosclerosis is the motto of the dat. The Study was carried out in 500 patients. In Group A (n = 140), the stapedius muscle and incudostapedial joint were preserved. In Group B (n = 360), the stapedius muscle was cut. One month after surgery in Group A patients, the Stapedius-Reflex (SR) was evoked in 75% and three months later in 90%. The mean Loudness Discomfort Level (LDL) after one month of surgery in Group A was 95dB while three months after it was increased to 110dB. Speech discrimination score (SDS) in Group A with 80 dB suprathreshold is 93% and in Group B it is only 72%. This study established the fact that the preservation of stapedial muscle and incudo stapedial join is beneficial and essential, whenever possible, in the surgery for otosclerosis.

Avaliação eletrofisiológica do nervo auditivo em pacientes normo-ouvintes com ausência do reflexo estapediano / Electrophysiological evaluation of the auditory nerve in normal hearing patients with absence of stapedial reflex

Introdução: O reflexo estapediano é uma contração do músculo estapédio, localizado na orelha média, induzido por um estímulo acústico intenso. É esperado que indivíduos com limiares auditivos dentro dos padrões de normalidade tenham reflexos estapedianos presentes, desde que haja integridade de orelha média. Entretanto, tem sido observada a existência de sujeitos ouvintes normais, com ausência de reflexo estapediano, o que pode sugerir a ausência do músculo estapédio ou até mesmo alteração do nervo auditivo (neuropatia). O Potencial Evocado de Tronco Encefálico (PEATE) é um exame objetivo e complementar da audição que avalia o funcionamento do nervo vestíbulo-coclear. Objetivo: O presente estudo foi realizado com o objetivo de se analisar os achados da avaliação eletrofisiológica do nervo auditivo, através do PEATE, em pacientes normo-ouvintes, sem queixas auditivas, com ausência do reflexo estapediano, confirmado pela Imitanciometria. Método: Foram estudados 68 sujeitos de ambos os sexos da faixa etária de 18 a 30 anos, sem queixas auditivas. Os procedimentos realizados compreenderam anamnese, inspeção do meato acústico interno, audiometria tonal liminar, logoaudiometria, imitanciometria e PEATE. Resultados: Os exames de PEATE da amostra populacional mostraram resultados dentro do padrão de normalidade com presença de onda I, III e V tendo os valores de latência absoluta e interpicos dentro dos padrões de normalidade, sugerindo integridade das vias auditivas centrais. Conclusão: A ausência dos reflexos estapedianos em pacientes normo-ouvintes, sem queixa auditiva por si só não é suficiente para diagnosticar a existência de neuropatia auditiva, necessitando ser empregado o exame de PEATE.

Introduction: The stapedial reflex is a stapedial muscle contraction located in the middle ear, induced by an intense acoustic stimulus. It is expected that individuals with auditory thresholds within the normality standards have stapedial reflexes once there is integrity of the middle ear. However, the existence of normal hearing persons, with absence of stapedial reflex, has been observed, which may suggest the absence of the stapedial muscle or even the alteration of the auditory nerve (neuropathy). The AEP (Encephalic Trunk Audition Evoked Potential) is an objective and complimentary exam of hearing that evaluates the functioning of the cochleovestibular nerve. Objective: This study was carried out aiming to review the auditory nerve electrophysiological evaluation findings, through AEP, in normal hearing patients without auditory complaints and with absence of the stapedial reflex, confirmed by imitanciometry. Method: We studied 68 individuals of both sexes and aged from 18 to 30 years without auditory complaints. The procedures carried out comprised anamnesis, internal acoustic meatus inspection, threshold tonal audiometry, logoaudiometry, imitanciometry and AEP. Results: The AEP exams of the population sample showed outcomes within the normality standard with presence of wave I, III and V, with absolute latency values and interpeaks within the normality standards, which suggested integrity of the central auditory passages. Conclusion: The absence of stapedial reflexes in normal hearing patients, without auditory complaint is not sufficient by itself to diagnose the existence of auditory neuropathy and requires application of the AEP exam.