Audiometric Measurements Research Articles

Hidden Hearing Loss? No Effect of Common Recreational Noise Exposure on Cochlear Nerve Response Amplitude in Humans.

This study tested hypothesized relationships between noise exposure and auditory deficits. Both retrospective assessment of potential associations between noise exposure history and performance on an audiologic test battery and prospective assessment of potential changes in performance after new recreational noise exposure were completed.Methods: 32 participants (13M, 19F) with normal hearing (25-dB HL or better, 0.25–8 kHz) were asked to participate in 3 pre- and post-exposure sessions including: otoscopy, tympanometry, distortion product otoacoustic emissions (DPOAEs) (f2 frequencies 1–8 kHz), pure-tone audiometry (0.25–8 kHz), Words-in-Noise (WIN) test, and electrocochleography (eCochG) measurements at 70, 80, and 90-dB nHL (click and 2–4 kHz tone-bursts). The first session was used to collect baseline data, the second session was collected the day after a loud recreational event, and the third session was collected 1-week later. Of the 32 participants, 26 completed all 3 sessions.Results: The retrospective analysis did not reveal statistically significant relationships between noise exposure history and any auditory deficits. The day after new exposure, there was a statistically significant correlation between noise “dose” and WIN performance overall, and within the 4-dB signal-to-babble ratio. In contrast, there were no statistically significant correlations between noise dose and changes in threshold, DPOAE amplitude, or AP amplitude the day after new noise exposure. Additional analyses revealed a statistically significant relationship between TTS and DPOAE amplitude at 6 kHz, with temporarily decreased DPOAE amplitude observed with increasing TTS.Conclusions: There was no evidence of auditory deficits as a function of previous noise exposure history, and no permanent changes in audiometric, electrophysiologic, or functional measures after new recreational noise exposure. There were very few participants with TTS the day after exposure - a test time selected to be consistent with previous animal studies. The largest observed TTS was approximately 20-dB. The observed pattern of small TTS suggests little risk of synaptopathy from common recreational noise exposure, and that we should not expect to observe changes in evoked potentials for this reason. No such changes were observed in this study. These data do not support suggestions that common, recreational noise exposure is likely to result in “hidden hearing loss”.

Prevalence of Hearing Loss in US Children and Adolescents

ImportanceThere have been concerns about increasing levels of hearing impairment in children and adolescents, especially in relation to noise exposure, because even mild levels of hearing loss can affect educational outcomes.ObjectiveTo further characterize changes in prevalence of hearing loss and noise exposures in the US pediatric population over time.Design, Setting, and ParticipantsThis is a retrospective analysis of demographic and audiometric data from the Third National Health and Nutrition Examination Survey (NHANES III, 1988-1994), NHANES 2005-2006, NHANES 2007-2008, and NHANES 2009-2010. The NHANES are nationally representative survey data sets collected and managed by the US National Center for Health Statistics, and this study includes a total of 7036 survey participants ages 12 to 19 years with available audiometric measurements.ExposuresHearing-related behaviors and risk factors such as history of ear infections, noise exposures, firearm use, and hearing protection use.Main Outcomes and MeasuresLevel of hearing loss measured by pure-tone audiometry, as well as high-frequency and low-frequency hearing loss and noise-induced threshold shifts.ResultsOverall, data from 7036 survey participants ages 12 to 19 years with available audiometric measurements were analyzed. The prevalence of hearing loss increased from NHANES III to NHANES 2007-2008 (17.0% to 22.5% for >15 dB hearing loss; absolute difference, 5.5%; 95% CI, 6.1%-10.3%) but decreased in the NHANES 2009-2010 to 15.2% (absolute difference, 7.2%; 95% CI, 2.0%-12.4%) with no significant overall secular trend identified. There was an overall rise in exposure to loud noise or music through headphones 24 hours prior to audiometric testing from NHANES III to NHANES 2009-2010. However, noise exposure, either prolonged or recent, was not consistently associated with an increased risk of hearing loss across all surveys. The most recent survey cycle showed that nonwhite race/ethnicity and low socioeconomic status are independent risk factors for hearing loss.Conclusions and RelevanceThis analysis did not identify significant changes in prevalence of hearing loss in US youth ages 12 to 19 years over this time period despite increases in reported noise exposures. No consistent associations were shown between noise exposure and hearing loss, though there was an association between racial/ethnic minority status and low socioeconomic status and increased risk of hearing loss. Ongoing monitoring of hearing loss in this population is necessary to elucidate long-term trends and identify targets for intervention.

Evaluation of Noise Exposure Secondary to Wind Noise in Cyclists.

Objective Determine if the noise levels of wind exposure experienced by cyclists reach levels that could contribute to noise-induced hearing loss. Study Design Industrial lab research. Setting Industrial wind tunnel. Subjects and Methods A commercial-grade electric wind tunnel was used to simulate different speeds encountered by a cyclist. A single cyclist was used during the simulation for audiometric measurements. Microphones attached near the ears of the cyclist were used to measure the sound (dB sound pressure level) experienced by the cyclist. Loudness levels were measured with the head positioned at 15-degree increments from 0 degrees to 180 degrees relative to the oncoming wind at different speeds (10-60 mph). Results Wind noise ranged from 84.9 dB at 10 mph and increased proportionally with speed to a maximum of 120.3 dB at 60 mph. The maximum of 120.3 dB was measured at the downwind ear when the ear was 90 degrees away from the wind. Conclusions Wind noise experienced by a cyclist is proportional to the speed and the directionality of the wind current. Turbulent air flow patterns are observed that contribute to increased sound exposure in the downwind ear. Consideration of ear deflection equipment without compromising sound awareness for cyclists during prolonged rides is advised to avoid potential noise trauma. Future research is warranted and can include long-term studies including dosimetry measures of the sound and yearly pre- and postexposure audiograms of cyclists to detect if any hearing loss occurs with long-term cycling.

Auditory Processing of Older Adults With Probable Mild Cognitive Impairment.

Studies suggest that deficits in auditory processing predict cognitive decline and dementia, but those studies included limited measures of auditory processing. The purpose of this study was to compare older adults with and without probable mild cognitive impairment (MCI) across two domains of auditory processing (auditory performance in competing acoustic signals and temporal aspects of audition). The Montreal Cognitive Assessment (Nasreddine et al., 2005) was used to classify participants as with or without probable MCI. In this cross-sectional study, participants (n = 79) completed 4 measures of auditory processing: Synthetic Sentence Identification with Ipsilateral Competing Message (Gates, Beiser, Rees, D'Agostino, & Wolf, 2002), Dichotic Sentence Identification (Fifer, Jerger, Berlin, Tobey, & Campbell, 1983), Adaptive Tests of Temporal Resolution (ATTR; Lister & Roberts, 2006; across-channel and within-channel subtests), and time-compressed speech (Wilson, 1993; Wilson, Preece, Salamon, Sperry, & Bornstein, 1994). Audiometry was also conducted. Those with probable MCI had significantly poorer performance than those without MCI on Synthetic Sentence Identification with Ipsilateral Competing Message, Dichotic Sentence Identification, and the ATTR within-channel subtest. No group differences were found for time-compressed speech, ATTR across-channel, or audiometric measures. Older adults with cognitive impairment not only have difficulty with competing acoustic signals but may also show poor temporal processing. The profile of auditory processing deficits among older adults with cognitive impairment may include multiple domains.

Characterization and Clinical Trials of the Prototype Ear Simulator Designed for Neonates Hearing Assessment

This article aims to describe the characterization of the new prototype ear simulator for neonates and demonstrate its utility in clinical measurements. Experimental evaluations have been performed in order to demonstrate consistency with the theoretical model in acoustic transfer impedance. Temperature and atmospheric pressure dependency measurements have been applied for verification of the stability of the ear simulator in variable environmental conditions. Thus, the main objective of this study is to outline the benefits of the new ear simulator in audiometric measurements for neonates. Acoustic transfer impedance of the ear simulator has been determined and compared with the theoretical model, and its environmental dependence has been studied between 100 Hz and 10,000 Hz. A modified method usually applied for reciprocity calibration of microphones has been used in measurements. Comparison of the new ear simulator with the IEC 60318-4 ear simulator and a \(2\,\hbox {cm}^{3}\) coupler has been presented. The ear simulator has been used to calibrate acoustics stimuli from an audiometer (Interacoustics AD226 with Otometrics insert earphone) and two otoacoustic emission devices (Otodynamics Otoport and Interacoustics Titan). The consistency of experimental evaluations in acoustic transfer impedance with the theoretical model has been confirmed. In clinical trials, an audiometer and two otoacoustic emission devices were investigated and a smaller standard deviation of 1.0 dB, 0.8 dB and 0.7 dB at 1 kHz, 2 kHz and 4 kHz, respectively, has been achieved compared to the old \(2\,\hbox {cm}^{3}\) coupler which has a 1.5 dB, 1.8 dB and 1.9 dB standard deviations at same frequencies. Average differences and standard deviations between the two couplers (IEC 60318-4 and the universal ear simulator) are \(11.4 \pm 0.3\,\hbox {dB}\) at 1 kHz, \(11.0 \pm 0.1\,\hbox {dB}\) at 2 kHz and \(13.3 \pm 0.2\,\hbox {dB}\) at 4 kHz. These differences represent the error incurred by using an adult ear simulator for neonates applications. The new universal ear simulator designed especially for hearing assessments of neonates has been characterized and used in clinical trials. The consistency between theoretical model and experimental measurements has been approved. Clinical trials showed that a more accurate calibration of OAE and audiometers for neonates would be possible. However, further applications for different age groups and broader clinical trials should be planned. Intercomparisons between different laboratories and clinics can maintain the comparability of hearing measurements and higher impact.

Sensorineural Hearing Loss in Selective Immunglobulin A Deficiency.

To assess hearing functions in pediatric patients with selective immunoglobulin A (IgA) deficiency (SIGAD). Pure-tone audiometry, acoustic impedance, otoacoustic emission, and brainstem audiometric measurements were taken during a non-infectious period in 28 patients with SIGAD and 28 healthy children with normal otoscopic examination. The results of the hearing tests were compared between the two groups. Two male patients and one female patient in the SIGAD group were found to have sensorineural hearing loss (SNHL). However, a comparison of the average pure tone cut-off values at 0.5, 1, 2, and 4 kHz did not reveal any statistically significant difference between the groups (p>0.05). Pediatric patients with SIGAD may exhibit SNHL at certain frequencies and require follow-up for the potential development of hearing loss.

Intra- and Intersubject Variability in Audiometric Measures and Loudness Judgments in Older Listeners with Normal Hearing.

This research was to document intra- and intersubject variability in measures of pure tone thresholds, loudness discomfort levels, and the Contour test of loudness for tonal and speech stimuli across 8 to 10 repeated test sessions over a period of almost 1 year in a group of 11 normal-hearing, older middle-aged adults (39 to 73 years, mean of 56 years). The measured pure tone thresholds and loudness discomfort levels were determined to be stable across sessions, with variability on the order of 5 dB. The categorical judgments for the Contour test for both warbled tones and spondaic speech stimuli decreased over time in level required for categories greater than comfortable. This result contrasts with reports of a slight increase over time when young, normal-hearing adults were tested in comparable measures. The intrasubject variability in the Contour test results was greatest for the 4,000-Hz tonal stimulus for which the largest time effects were observed. The intersubject variability was typically greater than the intrasubject variability and typically increased as the loudness category increased, with some exceptions. The results from this study can be used to aid in power and sample size analyses using these measures in future studies designed to compare effects of treatments based on changes in loudness judgments over time.

Longterm Results of a Screening Procedure for Adult Cochlear Implant Candidates

This study gives an estimation of the long term outcome of a screening procedure for cochlear implant candidacy in hearing aid users.In a recent retrospective study, hearing aid performance and audiometric measures in 185 subjects (318 ears) were analyzed. In the context of 2 years follow-up, the outcome of the ipsilateral screening procedure was analyzed. For patients who did receive a cochlear implant, their audiometric outcome measures were viewed into relation to their preoperative results.From the 96 ears identified as cochlear implant candidates, 34 were provided with a cochlear implant. 222 ears were identified as hearing aid users. Only 4 of these 222 ears were provided with a cochlear implant. Cochlear implant recipients with a preoperative speech recognition score with hearing aids above zero showed a mean improvement of 65% points in Freiburg monosyllabics.The audiometry-based screening procedure enables an effective management of the referral process of cochlear implant candidates.

Tinnitus and leisure noise

Objective: To study the relationship of life-time noise exposure and experience of tinnitus. Design: Audiometric measures included otoscopy, pure tone air- and bone-conduction hearing threshold levels (HTL) and otoacoustic emissions (OAEs). Participants completed questionnaires including demographic information, past hearing health, history of participation in loud leisure activities, and attitudes to noise. Study sample: A representative sample (1435) of the young (11–35 years old) Australian population. Results: Of the sample, 63% indicated they experienced tinnitus in some form. There was no correlation of tinnitus experience with HTL or OAE amplitudes. Although median octave band HTLs for those who experienced tinnitus “all the time” were slightly higher for those who did not, neither group exhibited HTLs outside clinically-normal values. Of those who experienced tinnitus a direct correlation was found between frequency of experience of tinnitus and increasing cumulative, life-time noise exposure. Those who experienced tinnitus were more likely to report noticing deterioration in their hearing ability over time and to report difficulty hearing in quiet and/or noisy situations. Conclusions: Experience of tinnitus was found throughout this young population but not associated with HTLs or variation in OAE amplitudes. Males experienced ‘permanent’ tinnitus at significantly greater rate than females.

Audiometric Comparison Between the First Patients With the Transcutaneous Bone Conduction Implant and Matched Percutaneous Bone Anchored Hearing Device Users

The transcutaneous bone conduction implant (BCI) is compared with bone-anchored hearing aids (BAHAs) under the hypothesis that the BCI can give similar rehabilitation from an audiological as well as patient-related point of view. Patients suffering from conductive and mixed hearing losses can often benefit more from rehabilitation using bone conduction devices (BCDs) rather than conventional air conduction devices. The most widely used BCD is the percutaneous BAHA, with a permanent skin-penetrating abutment. To overcome issues related to percutaneous BCDs, the trend today is to develop transcutaneous devices, with intact skin. The BCI is an active transcutaneous device currently in a clinical trial phase. A potential limitation of active transcutaneous devices is the loss of power in the induction link over the skin. To address this issue, countermeasures are taken in the design of the BCI, which is therefore expected to be as effective as percutaneous BCDs. An early observational study with a matched-pair design was performed to compare BCI and BAHA groups of patients over several audiometric measurements, including speech audiometry and warble tones thresholds with and without the device. Additionally, questionnaires were used to assess the general health condition, benefit, and satisfaction level of patients. No statistically significant difference was detected in any of the audiological measurements. The outcome of patient-related measurements was slightly superior for BCI in all subscales. Results confirm the initial hypothesis of the study: the BCI seems to be capable of providing as good rehabilitation as percutaneous devices for indicated patients.

Integrative versus Conventional Therapy of Chronic Otitis Media with Effusion and Adenoid Hypertrophy in Children: A Prospective Observational Study

Background: Chronic otitis media with effusion (COME) and adenoid hypertrophy (AH) are common entities in the pediatric population. The conventional treatment approach (conventional medicine; COM) involved mainly surgery after a period of close observation. In this study, we aimed to introduce an integrative, non-invasive approach (integrative medicine; IM) for COME, AH, and associated episodes of recurrent acute otitis media, and compared outcomes with conventional treatment. Methods: We conducted a prospective, non-randomized study in an integrative primary care pediatric practice and a conventional pediatric otolaryngological clinic, where treatment modality was determined by patient preference. Out of a total 101 patients aged 1-8 years, integrative therapy was chosen by 46, and conventional treatment by 55. All patients had COME and AH diagnosed by an otolaryngologist and had moderate to severe hearing impairment. COM treatment was based on close observation over time, nasal decongestants and surgical intervention. In contrast, the IM involved a complex personalized approach with non-invasive interventions, non-allopathic medications, diet and patient education. Results: The number of surgical interventions (adenoidectomy, pressure-equalization tube insertion, myringotomy) was significantly less in the IM cohort (1 of 28 vs. 15 of 35 in the COM group, p < 0.001). The frequency of antibiotic use was significantly less in the IM group (p < 0.001). The frequency of analgesic use was also significantly less in the IM group (p = 0.029). Improvement in tympanometric measures (normal A-type curve) was higher in IM patients compared to expected spontaneous remission during the observation period. Improvement in audiometric measures (intact hearing) of IM patients was also higher than expected compared to spontaneous remission during the observation period. Conclusion: Compared to conventional treatment, integrative treatment of patients with COME and AH showed significantly lower invasive surgical intervention rates and significantly decreased antibiotic and analgesic use. The integrative treatment was effective, safe and well tolerated.

Vestibular migraine screening in a migraine-diagnosed patient population, and assessment of vestibulocochlear function.

The primary aim of this study is to do a vestibular migraine scan in a population of patients with migraine diagnosis using the most recent standardized diagnosis criterion which is International Classification of Headache Disorders (ICHD) 3 Beta and to identify the epidemiological data. The second part of the study involves performing several vestibulocochlear tests on patients who received vestibular migraine (VM) diagnosis to collect data that may be important for diagnostic purposes by comparing the patients with normal population when necessary. Blind, cross-sectional study. Tertiary referral hospital. One hundred patients were scanned for VM using ICHD 3 Beta guideline. In order to evaluate the vestibulocochlear functions of the patients with VM diagnosis, audiometry, tympanometry, electrocochleography (EcochG), computerized dynamic posturography (CDP) and video head impulse test (vHIT) were performed; besides in order to evaluate the significance of the results of the tests, second group was formed with migraine patients without any vestibular complaints and control group was formed from healthy population when needed. VM prevalence was determined to be 21% in migraine patients which is much higher than stated in current literature. No significant difference was observed between migraine and VM patients with respect to audiometric and tympanometric measurements. According to the CDP results, balance defects were present in VM patients, even during attack-free periods. EcochG data suggests average SP/AP scores of VM patients are significantly higher than migraine patients. Furthermore, the number of patients who exceeded a limit value of 0.4 or 0.5 in SP/AP scores was significantly higher in VM patients than in migraine patients. Also vHIT results show that nearly half the VM patients, which is a significant ratio, have saccadic movements and this is thought to be compatible with peripheral vestibular involvement. Our results suggest VM disease is more common than previously thought. We believe that further EcochG-based studies would shed light on the controversial topic on the intersection and disjunction sets of MD and VM diseases. Although the results of the present study are compatible with peripheral vestibular effects, it is not possible to rule out another central mechanism at some other level.

Effects of age and hearing loss on coding frequency and amplitude modulation

Is phase-locking to temporal fine structure (TFS) selectively affected by hearing loss or ageing? This question has clinical relevance because audiometric measures may be insensitive to TFS deficits linked to auditory neuropathy/dyssynchrony and synaptopathy (“hidden hearing loss”). Previous work has suggested that slow-rate FM is coded via phase-locking to TFS, whereas fast-rate FM is converted to amplitude modulation (AM) via cochlear filtering. This hypothesis was tested by correlating performance in slow- and fast-rate FM with performance in tasks known to reflect TFS coding (interaural-time-difference detection, ITD) and cochlear filtering (forward masking patterns). Subjects with clinically normal hearing at low frequencies between the ages of 20 and 80 years were tested, with approximately 10 subjects per decade. Effects of low- and high-frequency hearing loss were also examined, while controlling for age. Although correlations were found between all measures of FM and AM, no clear specific effect of age was found on TFS coding (independent of AM coding). Preliminary results with hearing-impaired listeners suggest an effect of cochlear filtering that may not be specific to the fast-rate FM detection. Overall, the results do not provide strong evidence for TFS-specific deficits with either age or hearing loss. [Work supported by NIH grant R01DC005216.]

International survey of cochlear implant candidacy

Background: The goal of this work was to determine international differences in candidacy based on audiometric and speech perception measures, and to evaluate the information in light of the funding structure and access to implants within different countries.Method: An online questionnaire was circulated to professionals in 25 countries. There were 28 respondents, representing the candidacy practice in 17 countries.Results: Results showed differences in the funding model between countries. Unilateral implants for both adults and children and bilateral implants for children were covered by national funding in approximately 60% of countries (30% used medical insurance, and 10% self-funding). Fewer countries provided bilateral implants routinely for adults: national funding was available in only 22% (37% used medical insurance and 41% self-funding). Main evolving candidacy areas are asymmetric losses, auditory neuropathy spectrum disorders and electro-acoustic stimulation. For countries using speech-based adult candidacy assessments, the majority (40%) used word tests, 24% used sentence tests, and 36% used a mixture of both. For countries using audiometry for candidacy (70–80% of countries), the majority used levels of 75–85 dB HL at frequencies above 1 kHz. The United Kingdom and Belgium had the most conservative audiometric criteria, and countries such as Australia, Germany, and Italy were the most lenient. Countries with a purely self-funding model had greater flexibility in candidacy requirements.

Audiometric Characteristics of a Dutch DFNA10 Family With Mid-Frequency Hearing Impairment.

Mutations in EYA4 can cause nonsyndromic autosomal dominant sensorineural hearing impairment (DFNA10) or a syndromic variant with hearing impairment and dilated cardiomyopathy. A mutation in EYA4 was found in a Dutch family, causing DFNA10. This study is focused on characterizing the hearing impairment in this family. Whole exome sequencing was performed in the proband. In addition, peripheral blood samples were collected from 23 family members, and segregation analyses were performed. All participants underwent otorhinolaryngological examinations and pure-tone audiometry, and 12 participants underwent speech audiometry. In addition, an extended set of audiometric measurements was performed in five family members to evaluate the functional status of the cochlea. Vestibular testing was performed in three family members. Two individuals underwent echocardiography to evaluate the nonsyndromic phenotype. The authors present a Dutch family with a truncating mutation in EYA4 causing a mid-frequency hearing impairment. This mutation (c.464del) leads to a frameshift and a premature stop codon (p.Pro155fsX). This mutation is the most N-terminal mutation in EYA4 found to date. In addition, a missense mutation, predicted to be deleterious, was found in EYA4 in two family members. Echocardiography in two family members revealed no signs of dilated cardiomyopathy. Results of caloric and velocity step tests in three family members showed no abnormalities. Hearing impairment was found to be symmetric and progressive, beginning as a mid-frequency hearing impairment in childhood and developing into a high-frequency, moderate hearing impairment later in life. Furthermore, an extended set of audiometric measurements was performed in five family members. The results were comparable to those obtained in patients with other sensory types of hearing impairments, such as patients with Usher syndrome type IIA and presbyacusis, and not to those obtained in patients with (cochlear) conductive types of hearing impairment, such as DFNA8/12 and DFNA13. The mid-frequency hearing impairment in the present family was found to be symmetric and progressive, with a predominantly childhood onset. The results of psychophysical measurements revealed similarities to other conditions involving a sensory type of hearing impairment, such as Usher syndrome type IIA and presbyacusis. The study results suggest that EYA4 is expressed in the sensory cells of the cochlea. This phenotypic description will facilitate counseling for hearing impairment in DFNA10 patients.

Can use of a cold light source in endoscopic middle ear surgery cause sensorineural hearing loss?

Objectives: To investigate possible sensorineural hearing loss created by the use of a cold light source in patients undergoing endoscopic tympanoplasty surgery. Materials and Methods: The medical records of 203 patients, who underwent endoscopic Type 1 tympanoplasty surgery in our ear, nose, and throat clinic between 2012 and 2015, were checked retrospectively. Ninety-one patients were male and 112 were female, and their mean age was 34.4 ± 11.2 years. Results of audiometric measurements performed during the preoperative period and repeated 1 and 3 months postsurgery were compared to each other. Results: The mean duration of the operations was determined to be 52.4 ± 9.1 min. In addition, average preoperative bone-conduction was 11.4 ± 7.4 dB nHL. However, it was 9.57 ± 7.1 dB nHL and 9.51 ± 7.4 dB nHL, respectively, in the 1st and 3rd postoperative months. Levels of postoperative average bone-conduction at the 1st and 3rd month, as well as the thresholds of bone-conduction at 500, 1000, and 2000 Hz, were significantly lower than the preoperative results (P 0.05). Conclusion: Based on our findings, the increased heat generated by the use of a cold light source during an endoscopic tympanoplasty surgery is unlikely to cause the development of sensorineural hearing loss.

Evaluation of Performance With an Adaptive Digital Remote Microphone System and a Digital Remote Microphone Audio-Streaming Accessory System.

One purpose of this study was to evaluate the improvement in speech recognition obtained with use of 2 different remote microphone technologies. Another purpose of this study was to determine whether a battery of audiometric measures could predict benefit from use of these technologies. Sentence recognition was evaluated while 17 adults used each of 2 different hearing aids. Performance was evaluated with and without 2 different remote microphone systems. A variety of audiologic measures were administered to determine whether prefitting assessment may predict benefit from remote microphone technology. Use of both remote microphone systems resulted in improvement in speech recognition in quiet and in noise. There were no differences in performance obtained with the 2 different remote microphone technologies in quiet and at low competing noise levels, but use of the digital adaptive remote microphone system provided better speech recognition in the presence of moderate- to high-level noise. The Listening in Spatialized Noise–Sentence Test Prescribed Gain Amplifier (Cameron & Dillon, 2010) measure served as a good predictor of benefit from remote microphone technology. Each remote microphone system improved sentence recognition in noise, but greater improvement was obtained with the digital adaptive system. The Listening in Spatialized Noise–Sentence Test Prescribed Gain Amplifier may serve as a good indicator of benefit from remote microphone technology.

DPOAE measurements in comparison to audiometric measurements in hemodialyzed patients

ObjectiveTo investigate the early detection of the damage of cochlear activity by using distortion product otoacoustic emissions (DPOAE) (DP-gram) comparing to the results of the impedance audiometry. MethodsWe examined 53 patients including 43 hemodialyzed patients, and 10 controls. First it was applied a tympanometry, and then in normal results we applied impedance audiometry and DPOAE (DP-gram). ResultsWe found sensorineural hearing loss in 67% of audiometric results of the hemodialyzed patients and there was a decrease of the DPOAE amplitude in 77% of hemodialyzed patients. In the control group there was one patient (10%) with neurosensorial in high frequencies hearing loss in both measurements with audiometry and DPOAE. ConclusionsThere is a sensorineural hearing loss observed in most of the patients with chronic renal failure. DPOAE audiogram shows lower amplitudes than impedance audiometry and it can be used for the early detection of cochlear damage.

Audiometry-Based Screening Procedure for Cochlear Implant Candidacy.

This study defines a screening procedure for cochlear implant (CI) candidacy in hearing aid users by using simple audiometric measures. Within this retrospective study, hearing aid performance and audiometric measures in 185 subjects (318 ears) were analyzed. By means of a linear Naive Bayes classifier, the pure-tone average and the maximum monosyllabic score (PB(max)) were used to predict the aided monosyllabic word score and CI candidacy. The two parameters PB(max) and four-frequency hearing threshold average can be used to predict speech perception with hearing aids with reasonable accuracy for screening purposes. The classification has a sensitivity of 87% and a specificity of 91%. The classification can be represented by a simple linear formula. CI candidacy can be predicted based on commonly used audiometric measures.Cochlear implant candidacy may be considered if the difference between the average pure-tone threshold (in decibels) and PBmax (in percent) exceeds 8.

Hearing loss and Alzheimer's disease

Recent studies suggest that subjects with hearing loss are more likely to develop Alzheimer's disease. Hearing loss can be consecutive to presbycusis and/or to central auditory dysfunction. Standard audiometric measures (pure tone and speech intelligibility) allow the diagnosis of presbycusis. However, to demonstrate central auditory dysfunction, specific audiometric tests are needed such as noisy and/or dichotic tests. Actually, no consensus exists to investigate hearing loss in people with Alzheimer's disease though hearing loss may be an early manifestation of Alzheimer's disease. Until now, investigations and clinical procedure related to the diagnosis of Alzheimer's disease ignored the hearing ability of the patient. However, the major part of care management and investigations implies the patient's communication ability with the caregivers. Hearing loss may be one of the most unrecognized deficit in subjects with Alzheimer's disease. Auditory rehabilitation could benefit to the patient in order to lessen cognitive decline, but this must be investigated during longitudinal studies in order to clearly demonstrate their efficiency.