Acoustic Immittance Measures Research Articles

Audiological Characterization of Individuals with Cornelia de Lange Syndrome.

Introduction Cornelia de Lange Syndrome (CdLS) is a genetic disorder in which individuals may present sensorineural and/or conductive hearing loss, and the results of behavioral auditory assessments are not accurate. Objective To characterize the audiological profile of individuals with CdLS through behavioral, electroacoustic, and electrophysiological audiological assessments. Methods The study included 13 individuals of both sexes, aged between 3 and 26 years, with diagnoses confirmed through genetic studies. The following procedures were performed: medical history survey, otoscopy (pure-tone audiometry [PTA], speech audiometry, and acoustic immittance measures), and auditory brainstem response (ABR). Results In total 62.50% of the participants who underwent PTA had abnormal results (all of which were mild), with a predominance of bilateral conductive hearing loss (60%). Regarding tympanometry, 76.93% had abnormal results, most frequently type B (85.72% on the right and 88.89% on the left ear). Acoustic reflexes showed results compatible with tympanometry changes. Changes in ABR latency values compatible with middle-ear impairment were found in 8 of them (66.66%) - 3 had bilateral (37.50%), and 5 had unilateral impairments (62.50%). Conclusion Mild hearing loss was identified in 62.5% of the individuals with CdLS who underwent the behavioral audiological assessment. In the acoustic immittance measures, 76.9% of the participants presented a tympanometry curve characteristic of middle-ear changes. Acoustic reflexes were absent in 84.6% of the subjects. In the ABR, no changes were identified in auditory pathway integrity. On the other hand, changes in the absolute latency values were found, which are characteristic of conductive hearing loss.

Preliminary results of classifying otosclerosis and disarticulation using a convolutional neural network trained with simulated wideband acoustic immittance data

Current noninvasive methods of clinical practice often do not identify the causes of conductive hearing loss due to pathologic changes in the middle ear with sufficient certainty. Wideband acoustic immittance (WAI) measurement is noninvasive, inexpensive and objective. It is very sensitive to pathologic changes in the middle ear and therefore promising for diagnosis. However, evaluation of the data is difficult because of large interindividual variations. Machine learning methods like Convolutional neural networks (CNN) which might be able to deal with this overlaying pattern require a large amount of labeled measurement data for training and validation. This is difficult to provide given the low prevalence of many middle-ear pathologies. Therefore, this study proposes an approach in which the WAI training data of the CNN are simulated with a finite-element ear model and the Monte-Carlo method. With this approach, virtual populations of normal, otosclerotic, and disarticulated ears were generated, consistent with the averaged data of measured populations and well representing the qualitative characteristics of individuals. The CNN trained with the virtual data achieved for otosclerosis an AUC of 91.1 %, a sensitivity of 85.7 %, and a specificity of 85.2 %. For disarticulation, an AUC of 99.5 %, sensitivity of 100 %, and specificity of 93.1 % was achieved. Furthermore, it was estimated that specificity could potentially be increased to about 99 % in both pathological cases if stapes reflex threshold measurements were used to confirm the diagnosis. Thus, the procedures’ performance is comparable to classifiers from other studies trained with real measurement data, and therefore the procedure offers great potential for the diagnosis of rare pathologies or early-stages pathologies. The clinical potential of these preliminary results remains to be evaluated on more measurement data and additional pathologies.

Study of the peripheral and central auditory pathways in patients with mucopolysaccharidosis

ObjectiveTo investigate the peripheral and central auditory pathways in mucopolysaccharidosis (MPS) individuals. MethodThe research sample comprised 15 individuals (one female and 14 males), aged 8 to 46 years. The following procedures were used: medical history survey, otoscopy, speech and pure-tone threshold audiometry, acoustic immittance measures, and central auditory pathway assessment with brainstem auditory evoked potentials (BAEP) and long-latency auditory evoked potentials (LLAEP). ResultsThe pure-tone audiometry identified hearing loss in 13 individuals, and more than 90 % of the hearing loss was sensorineural. The degree of hearing loss was between mild to moderately severe with descendent configuration. Type A tympanogram predominated, and acoustic reflexes were present according to the types and degrees of hearing loss. Among the individuals with abnormal BAEP, longer wave III and V absolute latencies were the main findings. In addition, the unilateral absence of wave I was observed in two cases. In the LLAEP, longer latencies were observed in 14 individuals, and the most impaired components were the P1 and P3 in children and adolescents and the P2, N2 and P3 in adult individuals. ConclusionThe peripheral auditory pathway assessment revealed a predominantly sensorineural hearing loss, affecting mainly high frequencies, and in the central pathway was observed abnormal brainstem and cortical auditory processing in individuals with MPS.

Analysis of wideband acoustic immittance measurements in patients with unilateral Ménière's disease

Objective:To investigate the characteristics of wideband acoustic immittance（WAI） measurements in patients with unilateral Ménière's disease（MD） and evaluate the clinical value of WAI in diagnosis of MD. Methods:WAI was performed in 30 patients with unilateral MD（30 ears for symptomatic and 30 ears for asymptomatic） and in 26 healthy individuals（52 ears）（control group）. The WAI measurements, including the frequency first appearing two peaks in energy absorbance（EA） tympanogram, resonance frequency（RF）, the peak value of absorbance（PVA）, the integral area of absorbance（IAA）, EA curve at peak pressure, were analyzed. Results:①The occurrence of two peaks in EA tympanogram in both the MD symptomatic and asymptomatic ear was observed in 27 ears（84.4%）, and 38 ears（70.4%） in the control group, with no significant difference in the frequency of first appearing in two peaks onset between the groups（all P>0.05）. ②The RF of the MD symptomatic ears was significantly lower than that of the asymptomatic ears（t=-3.544, P=0.001） and that of the control subjects（t=2.084, P=0.041）; there was no difference of RF between the MD asymptomatic ears and the control group（P>0.05）. ③The PVA were significantly lower in both MD symptomatic（t=4.240, P<0.01） and asymptomatic ears（t=4.202, P=0.001） than in controls. ④The IAA in MD symptomatic（t=3.295, P=0.001） and asymptomatic ears（t=3.193, P=0.003） was significantly lower than in the control group. ⑤Comparison of the EA curve at peak pressure of the three groups: the EAs of MD symptomatic ears were lower than those of the control group at the range of 1 059-2 911 Hz（all P<0.05）; the EAs of MD symptomatic ears were lower than those of MD asymptomatic ears within 1 000 Hz and 1 834-2 119 Hz（all P<0.05）; the EAs of MD asymptomatic ears were lower than those of the control group at the range of 515-2 748 Hz（all P<0.05）. Conclusion:Symptomatic ears in unilateral MD patients show alterations in some WAI measurements compared to asymptomatic ears and/or controls, suggesting that middle ear mechanical fuction of the affected side may be modified due to the endolymphatic hydrops. The clinical significance of WAI needs to be further explored in the context of evaluating MD.

Investigation of hearing loss in elderly vertigo and dizziness patients in the past 10 years.

Vertigo and hearing loss are both prevalent in the elderly. This study retrospectively analyzed hearing test results from elderly patients experiencing vertigo and dizziness at ENT outpatient over a 10-year period, in order to study the patterns of hearing loss in this patient population. Nine thousand three hundred eighty four patients over 50 years old underwent retrospective collection and screening of outpatient diagnosis, pure tone audiometry, acoustic immittance measurement (tympanogram) and auditory brainstem response (ABR) test. The patient's audiograms are divided into 7 subtypes according to a set of fixed criteria. Meanwhile, K-Means clustering analysis method was used to classify the audiogram. The Jerger classification of tympanogram in elderly patients with vertigo and dizziness showed the majority falling under type A. The leading audiogram shapes were flat (27.81% in right ear and 26.89% in left ear), high-frequency gently sloping (25.97% in right ear and 27.34% in left ear), and high-frequency steeply sloping (21.60% in right ear and 22.53% in left ear). Meniere's disease (MD; 30.87%), benign recurrent vertigo (BRV; 19.07%), and benign paroxysmal positional vertigo (BPPV; 15.66%) were the most common etiologies in elderly vestibular diseases. We observed statistically significant differences in hearing thresholds among these vestibular diseases (P < 0.001). K-Means clustering analysis suggested that the optimal number of clusters was three, with sample sizes for the three clusters being 2,747, 2,413, and 4,139, respectively. The ANOVA statistical results of each characteristic value showed P < 0.001. The elderly patients often have mild to moderate hearing loss as a concomitant symptom with vertigo. Female patients have better hearing thresholds than males. The dominant audiometric shapes in this patient population were flat, high-frequency gently sloping, and high-frequency steeply sloping according to a set of fixed criteria. This study highlights the need for tailored strategies in managing hearing loss in elderly patients with vertigo and dizziness.

Predicting wideband real-ear-to-coupler differences in children using wideband acoustic immittance.

Individual differences in ear-canal acoustics introduce variability into hearing aid output that can affect speech audibility. Measuring ear-canal acoustics in young children can be challenging, and relying on normative real-ear-to-coupler difference (RECD) transforms can lead to large fitting errors. Acoustic immittance measures characterize the impedance of the ear and are more easily measured than RECD. Using 226 Hz tympanometry to predict the RECD is more accurate than using age-based average RECD values. The current study sought to determine whether wideband acoustic immittance measurements could improve predictions of wideband real-ear-to-coupler difference (wRECD). 150 children ages 2-10 years with intact tympanic membranes underwent wRECD and wideband acoustic immittance measures in each ear. Three models were constructed to predict each child's measured wRECD: the age-based average wRECD, 226 Hz admittance wRECD, and wideband absorbance wRECD. The average age-based wRECD model predicted the child's measured wRECD within 3 dB in 62% of cases, but both the 226 Hz admittance and wideband absorbance wRECD were within 3 dB in 90% of cases. Using individual 226 Hz or wideband absorbance to predict wRECD improved the accuracy and precision of transforms used for pediatric hearing aid fitting.

Hearing Thresholds at High Frequencies: Age as a Predictor of Values.

Introduction The audiological evaluation has the main objective of determining the integrity of the auditory system. Pure tone audiometry is a standardized behavioral procedure that aims to investigate auditory thresholds to describe auditory sensitivity. Despite being recognized since the mid-1960s, high frequency audiometry is still little used and explored in clinical practice, and its use is more considered as an audiological monitoring tool or as a research tool. Objective To analyze the audiological thresholds of high frequency audiometry in normal hearing individuals, and to verify the predictive capacity of age in the auditory thresholds of high frequency audiometry. Methods This is a retrospective, cross-sectional, and quantitative study that was approved by the Research Ethics Committee under number 5.039.583/21. The procedures were: clinical evaluation, pure tone audiometry, acoustic immittance measurements, and high frequency audiometry. All data collected from the exams were tabulated in an Excel spreadsheet and analyzed using appropriate statistical tests in the Statistical Package Social Sciences software. Results A total of 980 medical records were analyzed. The right and left ears presented similar tonal hearing thresholds for the frequencies of 12 kHz and 16 kHz. The threshold variance of 29.8% in the 12 kHz frequency can be explained by the variance of age, while, for the frequency of 16 kHz, this percentage is of 46.4%. Conclusion For 12 kHz hearing thresholds, an increase of 1 year leads to a 0.66 dBHL increase in hearing threshold. For 16 kHz hearing thresholds, an increase of 1 year leads to a 1.02 dBHL increase in hearing threshold.

Assessment of Middle Ear Function Using Wideband Acoustic Immittance: Current Practices and Future Prospects.

Acoustic immittance tests have been used in clinical practice for the assessment of middle ear function since the 1960s. In the following decades, single-frequency admittance tympanometry has become a staple test of middle ear function in routine audiological practice, and to a lesser extent, multifrequency tympanometry. The acoustic properties of middle ear are best understood through physiological assays of its gain spectrum, tested over a wide range of frequencies; i.e., the middle ear transfer function. Yet, clinical assessment with multi-frequency tympanometry has been limited to frequencies below 2000 Hz. Thanks to advances in probe characterization techniques, measurements of impedance at frequencies beyond 2,000 Hz have become possible. These advances ushered in a new frontier for acoustic immittance research and paved the way for a host of new wideband acoustic immittance (WAI) measures that promised improved clinical assessments through better approximation of the transfer function and acoustic mechanics of the middle ear. Translational and clinical research further developed and refined WAI for clinical use through establishment of clinical norms, emergence of data in ears with conductive disorders, and demonstrated improvements in test accuracy of WAI over single-frequency tympanometry for a variety of clinical populations. Together with emergence of commercially available systems, since the mid-2000s, these developments signal the emergence of WAI testing as a standard audiological tool for the assessment of the middle-ear function. Although clinical adoption of this promising diagnostic technology is lagging, widespread adoption is expected with further refinement of WAI measures, and as updated clinical practice guidelines recommend the incorporation of WAI testing into clinical test batteries (e.g., JCIH, 2019).[1]

Fundamental Concepts for Assessment and Interpretation of Wideband Acoustic Immittance Measurements.

Assessment of middle ear impedance using noninvasive electroacoustic measurements has undergone successive developments since its first clinical application in the 1940s, and gained widespread adoption since the 1970s in the form of 226-Hz tympanometry, and applications in multifrequency tympanometry. More recently, wideband acoustic immittance (WAI) is allowing unprecedented assessments of the middle ear acoustic mechanics thanks to the ability to record responses over a wide range of frequencies. The purpose of this article is to present fundamental concepts for the assessment and interpretation of wideband measures, including a review of acoustic impedance and its relation to the mass, stiffness, and resistance components of the middle ear. Additionally, an understanding of the middle ear transfer function reveals the relationship between impedance and middle-ear gain as a function of frequency. Wideband power absorbance, a WAI measure, quantifies the efficiency of sound conduction through the middle ear over a wide range of frequencies, and can serve as an analogous clinical measure to the transfer function. The interpretation of absorbance measures in ears with or without a conductive condition using absorbance measured at ambient pressure and pressurized conditions (wideband tympanometry) is described using clinical case examples. This article serves as an introduction to the fundamental principles of WAI measurements.

The Rise and Fall of Aural Acoustic Immittance Assessment Tools.

Clinical assessment of middle ear function has undergone multiple transformations and developments since the first acoustic impedance measurements were made in human ears nearly a century ago. The decades following the development of the first acoustic impedance bridge by Metz in 1946 witnessed a series of technological advancements leading to the widespread use of single-frequency admittance tympanometry in the 1960s. In the 1970s, multi-frequency and multi-component tympanometry (MFT) emerged for clinical use, allowing for a better understanding of the middle ear acoustic-mechanical response at frequencies between 200 and 2,000 Hz. MFT has not gained widespread clinical adoption despite its advantages over single-frequency tympanometry. More recent technological developments enabled assessment for frequencies greater than 2,000 Hz, leading to the advent of wideband acoustic immittance measures with capabilities for comprehensive assessment of middle ear acoustic mechanics, and a great potential for use of acoustic immittance testing in various diagnostic practices. This article reviews important historical markers in the development and operation of middle ear assessment tools and analysis methods. Technical and clinical factors underlying the emergence and adoption of different acoustic immittance tests as a standard of clinical practice are described. In addition, we discuss the likelihood for widespread adoption of wideband acoustic immittance and wideband tympanometry in future clinical practice.

A longitudinal study of the peripheral and central auditory pathways in individuals with acute lymphoid leukemia

ObjectiveTo characterize the peripheral and central auditory pathways in individuals with Acute Lymphoid Leukemia (ALL) and compare assessment results before and during chemotherapy. MethodThe study included 17 subjects with ALL, divided into two age groups: 3 to 6 (11 individuals) and 7 to 16 years old (6 individuals). Each subject was evaluated twice (before and 3 to 6 months after chemotherapy treatment) with the following procedures: medical history survey, otoscopy, Pure-Tone Threshold (PTA) and speech audiometry, acoustic immittance measures, Brainstem Auditory Evoked Potentials (BAEP) and Long-Latency Auditory Evoked Potentials (LLAEP). ResultsPTA was normal. Tympanometry was abnormal in the second assessment in 2 individuals aged 3 to 6 years. One subject in each age group had absent ipsilateral acoustic reflexes. In high-frequency audiometry, 1 individual had abnormal results. BAEP was abnormal in 5 (first assessment) and 7 individuals (second assessment) aged 3 to 6 years and 2 (first assessment) and 1 individual (second assessment) aged 7 to 16 years. As for LLAEP, P1 latency was increased in 5 (first assessment) and 7 individuals (second assessment) aged 3 to 6 years. ConclusionNo hearing loss was identified in the behavioral audiological assessment. BAEP was more affected in the 3-to-6-year-old group, with greater impairment in the lower brainstem in the first and second assessments. In LLAEP, P1 was the most impaired component in children aged 3 to 6 years, and P2 and N2 were so for those 7 to 16 years old, especially in the second assessment.

Habilidades auditivas em adultos jovens com e sem percepção de zumbido: um estudo de comparações

ABSTRACT Purpose Objective: To analyze auditory information processing responses in young adult subjects with tinnitus disorder. Methods A descriptive and quantitative study was conducted, involving 36 subjects aged between 19 and 35 years. The subjects were divided into two groups: Group 1 (20 subjects with chronic tinnitus) and Group 2 (16 subjects without tinnitus). All participants underwent medical history assessment, Visual Inspection of the External Auditory Canal, Pure-Tone Audiometry, Speech Audiometry, Acoustic Immittance Measures, and used Behavioral Central Auditory Processing Tests as an evaluation tool - Dichotic Digits Test (TDD), Frequency Pattern Test, Speech in Noise, Masking Level Difference, and Gap in Noise (GIN). Results Statistically significant differences were found between the groups for TDD responses in the left ear and for GIN in both ears. Conclusion Young adults with chronic tinnitus exhibit impairments in binaural integration and temporal resolution skills.

Conductive Hearing Loss Estimated From Wideband Acoustic Immittance Measurements in Ears With Otitis Media With Effusion.

Previous work has shown that wideband acoustic immittance (WAI) is sensitive to the volume of effusion present in ears with otitis media with effusion (OME). Prior work also demonstrates that the volume of the effusion appears to drive, or at least play a significant role in, how much conductive hearing loss (CHL) a child has due to a given episode of OME. Given this association, the goal of this work was to determine how well CHL could be estimated directly from WAI in ears with OME. Sixty-three ears from a previously published study on OME (ages 9 months to 11 years, 2 months) were grouped based on effusion volume (full, partial, or clear) determined during tympanostomy tube placement surgery and compared with age-matched normal control ears. Audiometric thresholds were obtained for a subset of the 34 ears distributed across the four groups. An electrical-analog model of ear-canal acoustics and middle-ear mechanics was fit to the measured WAI from individual ears. Initial estimates of CHL were derived from either (1) average absorbance or (2) the model component thought to represent damping in the ossicular chain. The analog model produced good fits for all effusion-volume groups. The two initial CHL estimates were both well correlated (87% and 81%) with the pure-tone average hearing thresholds used to define the CHL. However, in roughly a third of the ears (11/34), the estimate based on damping was too large by nearly a factor of two. This observation motivated improved CHL estimates. Our CHL estimation method can estimate behavioral audiometric thresholds (CHL) within a margin of error that is small enough to be clinically meaningful. The importance of this finding is increased by the challenges associated with behavioral audiometric testing in pediatric populations, where OME is the most common. In addition, the discovery of two clusters in the damping-related CHL estimate suggests the possible existence of two distinctly different types of ears: pressure detectors and power detectors.

Audiological profile and cochlear functionality in Williams syndrome.

to evaluate cochlear functionality in Williams syndrome (WS) individuals. a study with 39 individuals, being 22 with WS aged between 7 and 17 years, 15 male and 7 female, and 17 individuals with typical development and normal hearing. All individuals were evaluated using pure tone audiometry, acoustic immittance measurements, and Transient Evoked Otoacoustic Emissions (TEOAE). The audiological profile in individuals with WS was analyzed, and TEOAE responses were compared between WS individuals without hearing loss and typical developmental individuals. The hearing loss was observed in 50% of patients, being 78.95% sensorineural and 21.05% mixed. This hearing loss was predominantly mild to moderate, affecting mainly frequencies above 3 kHz. As for TEOAE, there was a higher incidence of absence and lower amplitude responses in individuals with WS. WS individuals have hair cell dysfunction, mainly in the basal region of the cochlea. Thus, TEOAE analysis is an important clinical resource to be considered in the routine audiological evaluation.

Prevalência de Dores Musculares e análise da Qualidade de Vida e Saúde Auditiva em Trabalhadores de Postos de Combustíveis

Introduction Gas station attendants are exposed to loud sounds and chemical compounds, working in rotating shifts and inadequate postures. Objective Describe the prevalence of musculoskeletal symptoms which affects those workers and evaluate the quality of life at work, correlating them with hearing evaluation. Method A cross-sectional study, with a control group, with 15 participants without exposure and other 20 with exposition. The Nordic Questionnaire of Musculoskeletal Symptoms and the Quality-of-Life Questionnaire at Work, short version, were used for evaluations. The exams performed were Tone Limit Audiometry, Acoustic Immittance Measurements and Brainstem Auditory Evoked Potential. Results The prevalent symptoms in the exposed group were pain in neck/cervical spine and hip/lower members, and the lumbar region. Hearing alterations were observed in 30% of the gas station attendants. There was a correlation between age and quality of life at work. Conclusion It is believed that the pain found can be a consequence of prolonged standing posture and lack of physical activity; symptoms that could be minimized by the adoption of ergonomic measures. However, although some audiological exams presented alterations, they were not enough to interfere in the quality of life at work, that was satisfactory for the groups. Keywords: Musculoskeletal; Noise. Solvents; Occupational exposure; Quality of life; Hypoacusis; Ototoxicity; Occupational Health.

The influence of otitis media with effusion on middle-ear impedance estimated from wideband acoustic immittance measurements.

The goal of this work was to estimate the middle-ear input impedance ( Zme) from wideband acoustic immittance (WAI) measures and determine whether Zme improves the clinical utility of WAI. The data used in this study were from a previously reported set of WAI measurements in ears with otitis media with effusion [OME; Merchant, Al-Salim, Tempero, Fitzpatrick, and Neely (2021). Ear Hear., published online]. Ears with OME were grouped based on effusion volume, which was confirmed during tube surgery. Zme was estimated from the measured ear-canal impedance. An electrical-analog model of ear-canal acoustics and middle-ear mechanics was used to model the ear canal and Zme. The model results fit the measured responses well for all conditions. A regression approach was used to classify the responses of different variable types to effusion volume groups and determine the specificity and sensitivity of the binary classifications. The Zme magnitude increased with increasing effusion volume. The area under the receiver operating characteristic curve (AUC) was compared for binary decisions of the OME categories. The Zme estimate resulted in a clinically meaningful improvement in the AUC for distinguishing healthy ears from ears with OME. Overall, these results suggest that Zme estimation may provide useful information of potential clinical value to improve the diagnostic utility of WAI measurements for OME.

Acoustic immittance measures and middle ear assessment: Current practice by South African audiologists.

BackgroundLimited research exists regarding South African audiologists’ practice with acoustic immittance. This study was part of a bigger study titled ‘Wideband acoustic immittance in adults living with human immunodeficiency virus’.ObjectivesThe purpose of the study was to explore current practice of South African audiologists regarding acoustic immittance measures, and to explore their perceived knowledge and views on acoustic immittance advancements.MethodA quantitative survey with a cross sectional design was employed. An electronic questionnaire was distributed to participants via professional associations of audiologists. Data was analysed through descriptive and inferential statistics.ResultsMost audiologists worked in private practice and conducted tympanometry with 226Hz probe tone and ipsilateral acoustic reflexes. There was no association between clinical setting, levels of qualification, and the use of tympanometry. None of the participants included multifrequency and multicomponent tympanometry (MFT) and/or wideband acoustic immittance (WAI) in their test battery. Most of the participants were not familiar with MFT and WAI. Familiarity with MFT and WAI were only associated with the level of qualification. Limited training and lack of equipment were major barriers to conducting some of the acoustic immittance measures. Most participants believed that they would include MFT and/or WAI in their test battery if they had access to the equipment.ConclusionCurrent findings raise training and clinical implications for the South African audiologists, including training institutions. These findings provide motivation for strategic resource allocation, planning and distribution of audiology clinics in the country if positive preventive audiology outcomes are to be achieved.

Measurements of ear-canal cross-sectional areas from live human ears with implications for wideband acoustic immittance measurements.

Wideband acoustic immittance (WAI) measures are noninvasive diagnostic measurements that require an estimate of the ear canal's area at the measurement location. Yet, physical measurements of the area at WAI probe locations are lacking. Methods to measure ear-canal areas from silicone molds were developed and applied to 169 subjects, ages 18-75 years. The average areas at the canal's first bend and at 12 mm insertion depth, which are likely WAI probe locations, were 63.4 ± 13.5 and 61.6 ± 13.5 mm2, respectively. These areas are substantially larger than those assumed by current FDA-approved WAI measurement devices as well as areas estimated with acoustical methods or measured on cadaver ears. Left and right ears from the same subject had similar areas. Sex, height, and weight were not significant factors in predicting area. Age cohort was a significant predictor of area, with area increasing with decade of life. A subset of areas from the youngest female subjects did not show an effect of race on area (White or Chinese). Areas were also measured as a function of insertion depth of 4.8-13.2 mm from the canal entrance; area was largest closest to the canal entrance and systematically decreased with insertion depth.

Electrophysiological and Behavioral Evaluation of Auditory Processing in Adults with Dysphonia.

Introduction Dysphonia is an oral communication disorder. The voice and hearing are interrelated aspects. Hearing is an important sensory input for monitoring the vocal pattern. The relation between hearing abilities and dysphonia represents a contribution both in scientific and in clinical terms, especially in cases in which satisfactory results are not achieved in the therapeutic process. Objective To characterize long-latency auditory evoked potential (P300) with tonal and complex stimuli, and to make a behavioral evaluation of auditory processing in adults with behavioral dysphonia. Method The sample used for the present study consisted of 20 subjects from both genders with ages ranging from 18 and 58, who were diagnosed with behavioral dysphonia. The evaluations occurred in a single 2-hour session, in which the procedures of clinical history, pure tone and speech audiometries, acoustic immittance measures, and behavioral and electrophysiological evaluations of auditory processing were performed. Results The descriptive measures of P3 latency elicited by tonal and complex stimuli showed similar results for the right and left ears, without statistically significant differences. In the qualitative analysis, the results observed were within the normality patterns for the P3 component for both tonal and complex stimuli. As for the behavioral evaluation of auditory processing, abnormal results were observed in 100% of the sample. Abnormalities were found in the auditory skills of ordering and temporal resolution and figure-background obtained from the duration pattern, random gap detection, and dichotic tests (syllables and words), respectively. Conclusion The evaluated patients presented central auditory processing disorder, evidenced by behavioral assessment.

Wideband Acoustic Immittance in Cochlear Implant Recipients: Reflectance and Stapedial Reflexes.

to characterize differences in wideband power reflectance for ears with and without cochlear implants (CIs), to describe electrically evoked stapedial reflex (eSR)-induced changes in reflectance, and to evaluate the benefit of a broadband probe for reflex threshold determination for CI recipients. It was hypothesized that reflectance patterns in ears with CIs would be consistent with increased middle ear stiffness and that reflex thresholds measured with a broadband probe would be lower compared with thresholds obtained with a single-frequency probe. Eleven CI recipients participated in both wideband reflectance and eSR testing. Ipsilateral reflexes were measured with three probes: a broadband chirp (swept from 200 to 8000 Hz), a 226 Hz tone, and a 678 Hz tone. Wideband reflectance measures acquired from 28 adults without CIs and with normal middle ear function served as a normative data set for comparison. Considering the group data, average reflectance was significantly greater for ears with CIs across 250 to 891 Hz and 4238 to 4490 Hz compared with the normative data set, although individual reflectance curves were variable. Some CI recipients also had low 226 Hz admittance, which contributed to the group finding, considering the control group had clinically normal 226 Hz admittance by design. Electrically evoked stapedial reflexes were measurable in nine of 14 ears (64.3%) and in 24 of 46 electrodes (52.5%) tested. Reflex-induced changes in reflectance patterns were unique to the participant/ear, but similar across activators (electrodes) within a given ear. In addition, reflectance values at or above 1000 Hz were affected most by activating the stapedial reflex, even in ears with clinically normal 226 Hz admittance. This is a higher-frequency range than has been reported for acoustically evoked reflex-induced reflectance changes and is consistent with increased middle ear stiffness at rest. Electrically evoked reflexes could be measured more often with the 678 Hz or the broadband probe compared with the 226 Hz probe tone. Although reflex thresholds were lower with the broadband probe compared with the 678 Hz probe in 16 of 24 conditions, this was not a statistically significant finding (Wilcoxon signed-rank test; p = 0.072). The applications of wideband acoustic immittance measurements (reflectance and reflexes) should also be considered for ears with CIs. Further work is needed to describe changes across time in ears with CIs to more fully understand the reflectance pattern indicating increased middle ear stiffness and to optimize measuring eSRs with a broadband probe.