Update on first African clinical trial on earpopper for the treatment of otitis media with effusion [FCT/UATH/HREC/PR/330].

Background: Otitis media with effusion (OME) is a middle ear condition characterized by the accumulation of serous fluid. It is common, though not exclusive; among children with its attendant developmental consequence if missed or untreated in early life. OME could be managed surgically, pharmacologically, or physiologically. EarPopper is a medical device developed for physiologic management of OME, Eustachian tube dysfunction, and related problems. We aim to ascertain the suitability/efficiency of EarPopper® device for the treatment of OME in our setting. Methodology: This is a prospective interventional study of volunteers diagnosed with OME from four (4) medical centers in Abuja. Pneumatic otoscopy, video-otoscopy, tympanometry, and pure-tone audiometry were done to confirm the diagnosis. Serial EarPopper sessions were performed twice weekly for 2-12 weeks, and outcome was assessed using patients' reports. The reports include the EarPopper scoring system (ESS) and audiometric parameters (before and after therapy). Results: Forty-five patients (17 males and 28 females) aged between 3-56 years were enrolled. Thirty-five were diagnosed with bilateral OME and 10 unilateral. All patients had Type-B tympanometry tracing with mild-to-moderate conductive hearing losses and ESS of between 2.45% and 84%. Out of the 45 participants, 32 (71.1%) completed the treatment, whereas 13 (28.9%) were lost to follow-up. Duration of EarPopper treatment ranged from 2 to 12 weeks. The outcome revealed improvement in 26/32 (81.3%) with significant reduction in ESS (1% to 9.8%). Six patients 6/32 (18.9%) had persistence symptoms. These 18.9% had the propensity to progress to chronic OME. Conclusion: This study highly suggests good prospect in using EarPopper for the management of OME among Africans.

Résumé Contexte: L'otite séreuse est une affection de l'oreille moyenne caractérisée par l'accumulation de liquide séreux. Cette condition est courante chez les enfants (mais pas exclusivement) avec des conséquences développementales qui s'élabore si la diagnostique est manquées ou non traitées pendant les premières années de vie. L'otite séreuse peut être prise en charge chirurgicalement, pharmacologiquement ou physiologiquement. " EarPopper " est un appareil médical développé pour la gestion physiologique de l'otite séreuse, du dysfonctionnement de la trompe d'Eustache et des problèmes associés. Nous visons à déterminer la convenance/l'efficacité de l'appareil EarPopper® pour le traitement de l'otite séreuse dans notre environnement. Méthodologie: Il s'agit d'une étude interventionnelle prospective sur des volontaires ayant reçu un diagnostic de l'otite séreuse dans quatre (4) centres médicaux à Abuja. Une otoscopie pneumatique, une vidéo-otoscopie, une tympanométrie et une audiométrie tonale ont été réalisées pour confirmer le diagnostic. Des sessions EarPopper® en série ont été effectuées deux fois par semaine pendant 2 à 12 semaines, et les résultats ont été évalués à l'aide des rapports des patients. Les rapports incluent le système de notation EarPopper® (ESS) et les paramètres audiométriques (avant et après la thérapie). Résultats: Quarante-cinq patients (17 hommes et 28 femmes) âgés de 3 à 56 ans ont été inclus. Trente-cinq ont reçu un diagnostic de l'otite séreuse bilatérale et 10 unilatérales. Tous les patients avaient un tracé tympanométrique de type B avec des pertes auditives de transmission légères à modérées et une ESS comprise entre 2,45 % et 84 %. Sur les 45 participants, 32 (71,1 %) ont terminé le traitement, tandis que 13 (28,9 %) ont été perdus de vue. La durée du traitement EarPopper® variait de 2 à 12 semaines. Les résultats ont révélé une amélioration dans 26/32 patients (81,3%) avec une réduction significative de l'ESS (1% à 9,8%). Six patients (6/32 ; 18,9 %) on présentaient avec des symptômes persistants. Ces 18,9% avaient une propension à évoluer vers une otite séreuse chronique. Conclusion: Cette étude suggère fortement de bonnes perspectives d'utilisation d'EarPopper® pour la gestion de l'otite séreuse chez les Africains. Mots-clés: EarPopper®, l'otite séreuse, tympanométrie.

Exploring the recruitment, ethical considerations, conduct and information dissemination of an audiology trial: a pretrial qualitative study (q-COACH).

INTRODUCTION: Randomised controlled trials (RCTs), while still considered the gold standard approach in medical research, can encounter impediments to their successful conduct and the dissemination of results. Pretrial qualitative research can usefully address some of these impediments, including recruitment and retention, ethical conduct, and preferred methods of dissemination. However, pretrial qualitative work is rarely undertaken in audiology. The Comparison of outcomes with hearing aids and cochlear implants in adults with moderately severe-to-profound bilateral sensorineural hearing loss (COACH) is a proposed RCT aiming to clarify when hearing aids (HAs) or cochlear implants (CIs) are the most suitable for different degrees of hearing loss and for which kinds of patients. q-COACH is a pretrial, qualitative study examining stakeholders' experiences of HAs and CIs, current clinical practices and stakeholders' perspectives of the design, conduct and dissemination plans for the proposed COACH study. METHODS: Twenty-four participants including general practitioners, audiologists, adult HA users, and adult support networks undertook either semi-structured individual or paired interviews and completed demographic questionnaires. Data were analysed thematically. RESULTS: Four key themes arose from this study: 1) rethinking sampling and recruitment strategies, 2) ethical considerations, 3) refining trial conduct, and 4) interconnected, appropriate and accessible methods of results dissemination. CONCLUSIONS: This qualitative investigation identified key considerations for the proposed RCT design, conduct and dissemination to help with successful implementation of COACH, and to indicate a plan of action at all RCT stages that would be acceptable to potential participants. By drawing on the perspectives of multiple key stakeholders and including a more general discussion of their experience and opinions of hearing loss, hearing device use and service availability, the study revealed experiential and ethical paradigms in which stakeholders operate. In so doing, q-COACH has exposed the benefits of preliminary qualitative investigations that enable detailed and rich understandings of the phenomenon at stake, forestalling problems and improving the quality of trial design, conduct and dissemination, while informing future RCT development discussions.

Association of Speech Processor Technology and Speech Recognition Outcomes in Adult Cochlear Implant Users.

OBJECTIVE: Determine association of advancements in speech processor technology with improvements in speech recognition outcomes. STUDY DESIGN: Retrospective cohort. SETTING: Tertiary referral center. PATIENTS: Adult unilateral cochlear implant (CI) recipients. INTERVENTION: Increasing novelty of speech processor defined by year of market availability. MAIN OUTCOME MEASURES: Consonant-Nucleus-Consonant (CNC) and Hearing in Noise Test (HINT) in quiet. RESULTS: From 1991 to 2016, 1,111 CNC scores and 1,121 HINT scores were collected from 351 patients who had complete data. Mean post-implantation CNC score was 53.8% and increased with more recent era of implantation (p < 0.001, analysis of variance [ANOVA]). Median HINT score was 87.0% and did not significantly vary with implantation era (p = 0.06, ANOVA). Multivariable generalized linear models were fitted to estimate the effect of speech processor novelty on CNC and HINT scores, each accounting for clustering of scores within patients and characteristics known to influence speech recognition outcomes. Each 5-year increment in speech processor novelty was independently associated with an increase in CNC score by 2.85% (95% confidence limits [CL] 0.26, 5.44%) and was not associated with change in HINT scores (p = 0.30). CONCLUSION: Newer speech processors are associated with improved CNC scores independent of the year of device implantation and expanding candidacy criteria. The lack of association with HINT scores can be attributed to a ceiling effect, suggesting that HINT in quiet may not be an informative test of speech recognition in the modern CI recipient. The implications of these findings with respect to appropriate interval of speech processor upgrades are discussed.

Implications and attitudes of audiologists towards smartphone integration in hearing healthcare.

In a relatively short period of time, modern societies have been transformed by the ubiquitous uptake of advanced and portable mobile communication, computation, and sensors available on smartphones. Looking forward, it is anticipated that smartphones will have an increasingly important role in health management including the delivery of hearing healthcare and operation of hearing instruments. OBJECTIVE: This paper provides a brief overview of the role of smartphones in audiologic rehabilitation and hearing research and reports on the findings of a survey assessing attitudes of audiologists towards smartphone integration in hearing healthcare. DESIGN: A total of 258 audiologists working in the United States completed the 10-item survey. RESULTS: The key finding from the survey is that practitioners generally expressed a high willingness to integrate smartphone technology in patient care. Counterintuitively, it was observed that clinicians with the least number of years of experience had relatively more negative attitudes toward smartphone integration in hearing healthcare than clinicians with comparatively more years of experience. CONCLUSIONS: The findings suggest that the attitudes of audiologists likely do not represent a barrier regarding smartphone integration in audiologic rehabilitation.

Tracking of Noise Tolerance to Measure Hearing Aid Benefit.

BACKGROUND: The benefits offered by noise reduction (NR) features on a hearing aid had been studied traditionally using test conditions that set the hearing aids into a stable state of performance. While adequate, this approach does not allow the differentiation of two NR algorithms that differ in their timing characteristics (i.e., activation and stabilization time). PURPOSE: The current study investigated a new method of measuring noise tolerance (Tracking of Noise Tolerance [TNT]) as a means to differentiate hearing aid technologies. The study determined the within-session and between-session reliability of the procedure. The benefits provided by various hearing aid conditions (aided, two NR algorithms, and a directional microphone algorithm) were measured using this procedure. Performance on normal-hearing listeners was also measured for referencing. RESEARCH DESIGN: A single-blinded, repeated-measures design was used. STUDY SAMPLE: Thirteen experienced hearing aid wearers with a bilaterally symmetrical (≤10 dB) mild-to-moderate sensorineural hearing loss participated in the study. In addition, seven normal-hearing listeners were tested in the unaided condition. DATA COLLECTION AND ANALYSIS: Participants tracked the noise level that met the criterion of tolerable noise level (TNL) in the presence of an 85 dB SPL continuous discourse passage. The test conditions included an unaided condition and an aided condition with combinations of NR and microphone modes within the UNIQUE hearing aid (omnidirectional microphone, no NR; omnidirectional microphone, NR; directional microphone, no NR; and directional microphone, NR) and the DREAM hearing aid (omnidirectional microphone, no NR; omnidirectional microphone, NR). Each tracking trial lasted 2 min for each hearing aid condition. Normal-hearing listeners tracked in the unaided condition only. Nine of the 13 hearing-impaired listeners returned after 3 mo for retesting in the unaided and aided conditions with the UNIQUE hearing aid. The individual TNL was estimated for each participant for all test conditions. The TNT index was calculated as the difference between 85 dB SPL and the TNL. RESULTS: The TNT index varied from 2.2 dB in the omnidirectional microphone, no NR condition to -4.4 dB in the directional microphone, NR on condition. Normal-hearing listeners reported a TNT index of -5.7 dB using this procedure. The averaged improvement in TNT offered by the NR algorithm on the UNIQUE varied from 2.1 dB when used with a directional microphone to 3.0 dB when used with the omnidirectional microphone. The time course of the NR algorithm was different between the UNIQUE and the DREAM hearing aids, with the UNIQUE reaching a stable TNL sooner than the DREAM. The averaged improvement in TNT index from the UNIQUE directional microphone was 3.6 dB when NR was activated and 4.4 dB when NR was deactivated. Together, directional microphone and NR resulted in a total TNT improvement of 6.5 dB. The test-retest reliability of the procedure was high, with an intrasession 95% confidence interval (CI) of 2.2 dB and an intersession 95% CI of 4.2 dB. CONCLUSIONS: The effect of the NR and directional microphone algorithms was measured to be 2-3 and 3.6-4.4 dB, respectively, using the TNT procedure. Because of its tracking property and reliability, this procedure may hold promise in differentiating among some hearing aid features that also differ in their time course of action.

Difficult conversations: talking about cost in audiology consultations with older adults.

OBJECTIVE: Financial cost is a barrier for many older adults in their decision to obtain hearing aids (HAs). This study aimed to examine conversations about the cost of HAs in detail within initial audiology appointments. DESIGN: Sixty-two initial audiology appointments were video-recorded. The data were analysed using conversation analysis. STUDY SAMPLE: Participants included 26 audiologists, 62 older adults and 17 companions. RESULTS: Audiologists and clients displayed interactional difficulty during conversations about cost. Clients often had emotional responses to the cost of HAs, which were not attended to by audiologists. It was typical for audiologists to present one HA cost option at a time, which led to multiple rejections from clients which made the interactions difficult. Alternatively, when audiologists offered multiple cost options at once this led to a smoother interaction. CONCLUSIONS: Audiologists and clients were observed to have difficulty talking about HA costs. Offering clients multiple HA cost options at the same time can engage clients in the decision-making process and lead to a smoother interaction between audiologist and client in the management phase of appointments.

Examination of Insert Ear Interaural Attenuation (IA)Values in Audiological Evaluations.

PURPOSE: The purpose of this study was to evaluate Interaural Attenuation (IA) in frequency base in the insert earphones that are used in audiological assessments. METHODS: Thirty healthy subjects between 18-65 years of age (14 female and 16 male) participated in our study. Otoscopic examination was performed on all participants. Audiological evaluations were performed using the Interacoustics AC40 clinical audiometer and ER-3A insert earphones. IA value was calculated by subtracting good ear bone conduction hearing thresholds of the worst airway hearing threshold. RESULTS: In our measuring for 0.125-8.0 kHz frequency were performed in our audiometry device separately for each frequency. IA amount in the results we found in 1000 Hz and below frequencies about 75-110 dB range avarage is 89±5dB, in above 1000 Hz frequencies in 50-95 dB range and avarage it is changed to 69±5dB. CONCLUSION: According to the obtained findings the quantity of melting in the transition between the ears are increasing with the insert earphones. The insert earphone should be beside supraaural earphone that is routinely used in clinics. Difficult masking applications due to the increase in the value of IA can be easily done with insert earphones.

A practical guide to cochlear implantation in adults with long durations of monaural sound deprivation.

OBJECTIVE: This paper aims to summarize published findings by the authors and integrate these within current literature to support clinical guidelines when choosing an ear for cochlear implantation in adults with long-term monaural sound deprivation. STUDY SAMPLE: Four retrospective cohort studies based on data collected in five cochlear implantation centres with adults with bilateral hearing loss who used a single hearing aid for at least 15 years prior to unilateral or bilateral cochlear implantation. DESIGN: Review, integration and interpretation of retrospective cohort studies to support clinical recommendations. RESULTS: In this population, the prelingual nature of the hearing loss and the duration of bilateral significant hearing loss were the most reliable predictors of cochlear implantation outcomes. Importantly, the duration of sound deprivation in the ear to be implanted was not a significant predictor of speech recognition scores after cochlear implantation and should carry less weight in making recommendations. CONCLUSIONS: In most adults with postlingual hearing loss and long-term monaural sound deprivation, the sound-deprived sound deprivation ear should be preferred for implantation. For adults with prelingual deafness and monaural sound deprivation, the decision should weigh the risks of obtaining poorer results with the cochlear implant compared to the benefits of accessing binaural hearing.

Does the EarPopper(®) device improve hearing outcomes in children with persistent otitis media with effusion? A randomised single-blinded controlled trial.

OBJECTIVE: To provide an independent evaluation of the efficacy and safety of the EarPopper(®) in improving hearing outcomes in children with otitis media with effusion (OME) and reducing the ventilation tube insertion rate. STUDY DESIGN: Randomised single-blinded controlled trial. SETTING: The Ear Nose and Throat Department of a district general hospital (Heatherwood and Wexham Park). PARTICIPANTS AND METHODS: Twenty-nine children aged between 4 and 11 years diagnosed with persistent OME lasting at least 3 months with an average hearing of 25 dBHL or worse in the better ear were randomised to a treatment or control group for 7 weeks using random computer-generated codes. Syndromic children, children with developmental delay, previous grommets and cleft palate were excluded. The audiologists were blinded at the final post-treatment audiogram. RESULTS: After the seven-week period, the mean improvement in air conduction across all frequencies was 10.9 dBHL in the treatment group (P < 0.001) and 3.6 dBHL in the control group (P = 0.201). At every frequency, the treatment group had larger improvements in air conduction, the largest being at 4 kHz where the mean air conduction in both ears improved by 14.8 dBHL. Compliance with the EarPopper(®) was over 90%, the only side-effect reported being discomfort in the ears immediately after use which resolved and did not affect compliance. The ventilation tube insertion rate was 53.3% in the treatment group and 78.6% in the control group. Median follow-up time for all patients is 47.7 months. CONCLUSION: Our study shows that the EarPopper(®) is a safe, effective treatment option for children with hearing loss from persistent OME, and it reduces the rate of ventilation tube insertion. More studies with larger sample sizes are required to support our findings.

A Browser-Server-Based Tele-audiology System That Supports Multiple Hearing Test Modalities.

INTRODUCTION: Millions of global citizens suffering from hearing disorders have limited or no access to much needed hearing healthcare. Although tele-audiology presents a solution to alleviate this problem, existing remote hearing diagnosis systems support only pure-tone tests, leaving speech and other test procedures unsolved, due to the lack of software and hardware to enable communication required between audiologists and their remote patients. This article presents a comprehensive remote hearing test system that integrates the two most needed hearing test procedures: a pure-tone audiogram and a speech test. MATERIALS AND METHODS: This enhanced system is composed of a Web application server, an embedded smart Internet-Bluetooth(®) (Bluetooth SIG, Kirkland, WA) gateway (or console device), and a Bluetooth-enabled audiometer. Several graphical user interfaces and a relational database are hosted on the application server. The console device has been designed to support the tests and auxiliary communication between the local site and the remote site. RESULTS: The study was conducted at an audiology laboratory. Pure-tone audiogram and speech test results from volunteers tested with this tele-audiology system are comparable with results from the traditional face-to-face approach. CONCLUSIONS: This browser-server-based comprehensive tele-audiology offers a flexible platform to expand hearing services to traditionally underserved groups.

Paired comparisons of nonlinear frequency compression, extended bandwidth, and restricted bandwidth hearing aid processing for children and adults with hearing loss.

BACKGROUND: Preference for speech and music processed with nonlinear frequency compression (NFC) and two controls (restricted bandwidth [RBW] and extended bandwidth [EBW] hearing aid processing) was examined in adults and children with hearing loss. PURPOSE: The purpose of this study was to determine if stimulus type (music, sentences), age (children, adults), and degree of hearing loss influence listener preference for NFC, RBW, and EBW. RESEARCH DESIGN: Design was a within-participant, quasi-experimental study. Using a round-robin procedure, participants listened to amplified stimuli that were (1) frequency lowered using NFC, (2) low-pass filtered at 5 kHz to simulate the RBW of conventional hearing aid processing, or (3) low-pass filtered at 11 kHz to simulate EBW amplification. The examiner and participants were blinded to the type of processing. Using a two-alternative forced-choice task, participants selected the preferred music or sentence passage. STUDY SAMPLE: Participants included 16 children (ages 8-16 yr) and 16 adults (ages 19-65 yr) with mild to severe sensorineural hearing loss. INTERVENTION: All participants listened to speech and music processed using a hearing aid simulator fit to the Desired Sensation Level algorithm v5.0a. RESULTS: Children and adults did not differ in their preferences. For speech, participants preferred EBW to both NFC and RBW. Participants also preferred NFC to RBW. Preference was not related to the degree of hearing loss. For music, listeners did not show a preference. However, participants with greater hearing loss preferred NFC to RBW more than participants with less hearing loss. Conversely, participants with greater hearing loss were less likely to prefer EBW to RBW. CONCLUSIONS: Both age groups preferred access to high-frequency sounds, as demonstrated by their preference for either the EBW or NFC conditions over the RBW condition. Preference for EBW can be limited for those with greater degrees of hearing loss, but participants with greater hearing loss may be more likely to prefer NFC. Further investigation using participants with more severe hearing loss may be warranted.

Automatic quality assessment and peak identification of auditory brainstem responses with fitted parametric peaks.

The recording of the auditory brainstem response (ABR) is used worldwide for hearing screening purposes. In this process, a precise estimation of the most relevant components is essential for an accurate interpretation of these signals. This evaluation is usually carried out subjectively by an audiologist. However, the use of automatic methods for this purpose is being encouraged nowadays in order to reduce human evaluation biases and ensure uniformity among test conditions, patients, and screening personnel. This article describes a new method that performs automatic quality assessment and identification of the peaks, the fitted parametric peaks (FPP). This method is based on the use of synthesized peaks that are adjusted to the ABR response. The FPP is validated, on one hand, by an analysis of amplitudes and latencies measured manually by an audiologist and automatically by the FPP method in ABR signals recorded at different stimulation rates; and on the other hand, contrasting the performance of the FPP method with the automatic evaluation techniques based on the correlation coefficient, FSP, and cross correlation with a predefined template waveform by comparing the automatic evaluations of the quality of these methods with subjective evaluations provided by five experienced evaluators on a set of ABR signals of different quality. The results of this study suggest (a) that the FPP method can be used to provide an accurate parameterization of the peaks in terms of amplitude, latency, and width, and (b) that the FPP remains as the method that best approaches the averaged subjective quality evaluation, as well as provides the best results in terms of sensitivity and specificity in ABR signals validation. The significance of these findings and the clinical value of the FPP method are highlighted on this paper.

Patient-centred audiological rehabilitation: perspectives of older adults who own hearing aids.

OBJECTIVE: Patient-centred care is a term frequently associated with quality health care. Despite extensive literature from a range of health-care professions that provide description and measurement of patient-centred care, a definition of patient-centredness in audiological rehabilitation is lacking. The current study aimed to define patient-centred care specific to audiological rehabilitation from the perspective of older adults who have owned hearing aids for at least one year. DESIGN: Research interviews were conducted with a purposive sample of older adults concerning their perceptions of patient-centredness in audiological rehabilitation, and qualitative content analysis was undertaken. STUDY SAMPLE: The participant sample included ten adults over the age of 60 years who had owned hearing aids for at least one year. RESULTS: Data analysis revealed three dimensions to patient-centred audiological rehabilitation: the therapeutic relationship, the players (audiologist and patient), and clinical processes. Individualised care was seen as an overarching theme linking each of these dimensions. CONCLUSIONS: This study reported two models: the first model describes what older adults with hearing aids believe constitutes patient-centred audiological rehabilitation. The second provides a guide to operationalised patient-centred care. Further research is required to address questions pertaining to the presence, nature, and impact of patient-centred audiological rehabilitation.

Availability of audiological equipment and protocols for paediatric assessment and hearing aid fitting in Gauteng, South Africa.

BACKGROUND: Accurate diagnosis and management of hearing loss (HL) is based on valid and accurate ear-specific and frequency-specific information. This is especially relevant as non-optimal hearing amplification as part of early hearing detection and intervention programmes may result in further delays in the speech and language development of children with HL. Audiological measures utilised may vary according to the age, cognitive ability and physical ability of the infant or child. It is therefore important to compare and critically evaluate current clinical practice in order to recommend guidelines for paediatric audiology in South Africa. OBJECTIVES: To determine the availability of audiological equipment and clinical protocols used by audiologists in Gauteng for paediatric audiological assessment and hearing aid (HA) fitting. METHOD: A descriptive, cross-sectional survey research design was utilised to describe the availability of clinical audiological equipment and protocols used by audiologists in Gauteng, South Africa for paediatric assessment and HA fitting. Eighteen audiology departments, eleven public hospitals and seven private practices were included in the study. RESULTS: Results revealed the limited availability of departmental protocols within departments for paediatric assessment and HA fitting. Although there appeared to be a wide variety of equipment available to audiologists in public sector hospitals and private practice, a lack of high-frequency tympanometers and equipment for real ear measurements was revealed. CONCLUSION: These findings highlight the need for the development and use of current, evidence-based practice guidelines for paediatric audiological assessment and HA fitting in South Africa. These guidelines should include a list of essential equipment required for paediatric assessment and HA fitting. Current, evidence-based practice guidelines for paediatric HA fitting are important in ensuring that secondary developmental delays associated with a delay in early intervention for children with HL are reduced.

Curtis's cephaloscope: deafness and the making of surgical authority in London, 1816-1845.

Aural surgery is a branch of nineteenth-century medicine and surgery providing specialized treatment for ear diseases. During the 1830s, faced with a "popular prejudice" against the curability of deafness as well as intraprofessional rivalries and continuous accusations of quackery, aurists found their surgical authority questioned and their field's value threatened. In an attempt to bolster aural surgery's reputation, in 1841, the aurist John Harrison Curtis (1778-1856) introduced his new diagnostic instrument, the cephaloscope, which could not only improve diagnosis but also provide approaches for regulating aural knowledge, thus strengthening aural surgery's authority. This article examines the motives underlying Curtis's introduction of the cephaloscope and the meanings it held for the occupational group at large.

Pediatric applications of wideband acoustic immittance measures.

Wideband acoustic immittance (WAI) measures have potential capability to improve newborn hearing screening outcomes and middle ear diagnosis for infants and children. To fully capitalize on these immittance measures for pediatric hearing care, developmental and pathologic effects need to be fully understood. Published literature on wideband immittance (reflectance, absorbance, tympanometry, and acoustic reflexes) is reviewed in this article to determine pathologic effects in newborns, infants, and children relative to standard audiologic tests such as otoacoustic emissions (OAEs), standard tympanometry, air and bone conduction auditory brainstem response, and otoscopy. Infants and children with surgically confirmed otitis media with effusion have lower absorbance in the mid-frequency range (1 to 3 kHz) for the affected ear(s). Newborns that do not pass OAE screening at birth also have lower absorbance for frequencies from 1 to 3 kHz, suggesting that nonpass results are frequently associated with middle ear issues at birth. In Newborn Hearing Screening Programs, WAI may help to interpret hearing screening results. Conclusions are limited by the fact that the true status of the middle ear and cochlea are not known for newborns and infants in studies that use OAE or tympanometry as the reference standard. Likelihood ratios for reflectance against surgery gold standards range from diagnostically suggestive to informative. Although some of the results are promising, limited evidence and methodological considerations restrict the conclusions that can be drawn regarding the diagnostic accuracy of WAI technologies in infants and children. Additional investigations using stronger gold standard comparisons are needed to determine which tools can most accurately predict middle ear status in the pediatric population.

Assessment of ear disorders using power reflectance.

This article describes the effect of various pathologies on power reflectance (PR) and absorbance measured in human adults. The pathologies studied include those affecting the tympanic membrane, the middle-ear ossicles, the middle-ear cavity, the inner ear, and intracranial pressure. Interesting pathology-induced changes in PR that are statistically significant have been reported. Nevertheless, because measurements of PR obtained from normal-hearing subjects have large variations and some pathology-induced changes are small, it can be difficult to use PR alone for differential diagnosis. There are, however, common clinical situations without reliable diagnostic methods that can benefit from PR measurements. These conditions include ears with a normal-appearing tympanic membrane, aerated middle-ear cavity, and unknown etiology of conductive hearing loss. PR measurements in conjunction with audiometric measurements of air­bone gap have promise in differentiating among stapes fixation, ossicular discontinuity, and superior semicircular canal dehiscence. Another possible application is to monitor an individual for possible changes in intracranial pressure. Descriptions of mechanisms affecting PR change and utilization of PR measurements in clinical scenarios are presented.

Factors that introduce intrasubject variability into ear-canal absorbance measurements.

Wideband immittance measures can be useful in analyzing acoustic sound flow through the ear and also have diagnostic potential for the identification of conductive hearing loss as well as causes of conductive hearing loss. To interpret individual measurements, the variability in test­retest data must be described and quantified. Contributors to variability in ear-canal absorbance­based measurements are described in this article. These include assumptions related to methodologies and issues related to the probe fit within the ear and potential acoustic leaks. Evidence suggests that variations in ear-canal cross-sectional area or measurement location are small relative to variability within a population. Data are shown to suggest that the determination of the Thévenin equivalent of the ER-10C probe introduces minimal variability and is independent of the foam ear tip itself. It is suggested that acoustic leaks in the coupling of the ear tip to the ear canal lead to substantial variations and that this issue needs further work in terms of potential criteria to identify an acoustic leak. In addition, test­retest data from the literature are reviewed.

Alternative ear-canal measures related to absorbance.

Several alternative ear-canal measures are similar to absorbance in their requirement for prior determination of a Thévenin-equivalent sound source. Examples are (1) sound intensity level, (2) forward pressure level, (3) time-domain ear-canal reflectance, and (4) cochlear reflectance. These four related measures are similar to absorbance in their utilization of wideband stimuli and their focus on recording ear-canal sound pressure. The related measures differ from absorbance in how the ear-canal pressure is analyzed and in the type of information that is extracted from the recorded response. Sound intensity level and forward pressure level have both been shown to be better as measures of sound level in the ear canal compared with sound pressure level because they reduced calibration errors due to standing waves in studies of behavioral thresholds and otoacoustic emissions. Time-domain ear-canal reflectance may be used to estimate ear-canal geometry and may have the potential to assess middle ear pathology. Cochlear reflectance reveals information about the inner ear that is similar to what is provided by other types of otoacoustic emissions, and may have theoretical advantages that strengthen its interpretation.

An overview of wideband immittance measurements techniques and terminology: you say absorbance, I say reflectance.

This article reviews the relationships among different acoustic measurements of the mobility of the tympanic membrane, including impedance, admittance, reflectance, and absorbance, which the authors group under the rubric of immittance measures. Each of these quantities is defined and related to the others. The relationship is most easily grasped in terms of a straight rigid ear canal of uniform area terminated by a uniform middle ear immittance placed perpendicular to the long axis of the ear canal. Complications due to variations from this geometry are discussed. Different methods for measuring these quantities are described, and the assumptions inherent within each method are made explicit. The benefits of wideband measurements of these quantities are described, as are the benefits and limitations of different components of immittance and reflectance/absorbance. While power reflectance (the square of the magnitude of pressure reflectance) is relatively invariant along the length of the ear canal, it has the disadvantage that it ignores phase information that may be useful in assessing the presence of acoustic leaks in ear-canal measurements and identifying other potential error sources. A combination of reflectance and impedance magnitude and angle give a more complete description of the middle ear from measurements in the ear canal.