Comparison of auditory brainstem response and electrocochleography to assess the coupling efficiency of active middle ear implants.

Aim: This study aimed to compare the effectiveness of auditory brainstem response (ABR) and extracochlear electrocochleography (ECochG) in objectively evaluating the coupling efficiency of floating mass transducer (FMT) placement during active middle ear implant (AMEI) surgery. Methods: We enrolled 15 patients (mean age 58.5 ± 19.4 years) with mixed hearing loss who underwent AMEI implantation (seven ossicular chain and eight round window couplings). Before the surgical procedure, an audiogram was performed. We utilized a clinical measurement system to stimulate and record intraoperative ABR and ECochG recordings. The coupling efficiency of the VSB was evaluated through ECochG and ABR threshold measurements. Postoperatively, we conducted an audiogram and a vibrogram. Results: In all 15 patients, ABR threshold testing successfully determined intraoperative coupling efficiency, while ECochG was successful in only eight patients. In our cohort, ABR measurements were more practical, consistent, and robust than ECochG measurements. Coupling efficiency, calculated as the difference between vibrogram thresholds and postoperative bone conduction thresholds, was found to be more accurately predicted by ABR measurements (p = 0.016, R2 = 0.37) than ECochG measurements (p = 0.761, R2 = 0.02). We also found a non-significant trend toward better results with ossicular chain coupling compared to round window coupling. Conclusion: Our findings suggest that ABR measurements are more practical, robust, and consistent than ECochG measurements for determining coupling efficiency during FMT placement surgery. The use of ABR measurements can help to identify the optimal FMT placement, especially with round window coupling. Finally, we offer normative data for both techniques, which can aid other clinical centers in using intraoperative monitoring for AMEI placement.

Using a Bone Conduction Hearing Device as a Tactile Aid.

BACKGROUND: With the advent of cochlear implants, tactile aids for the profoundly deaf became obsolete decades ago. Nevertheless, they might still be useful in rare cases. We report the case of a 25-year-old woman with Bosley-Salih-Alorainy Syndrome and bilateral cochlear aplasia. METHODS: After it was determined that cochlear or brainstem implants were not an option and tactile aids were not available anymore, a bone conduction device (BCD) on a softband was tried as a tactile aid. The usual retroauricular position and a second position close to the wrist, preferred by the patient, were compared. Sound detection thresholds were measured with and without the aid. Additionally, three bilaterally deaf adult cochlear implant users were tested under the same conditions. RESULTS: At 250-1000 Hz, sounds were perceived as vibrations above approximately 45-60 dB with the device at the wrist. Thresholds were approximately 10 dB poorer when placed retroauricularly. Differentiation between different sounds seemed difficult. Nevertheless, the patient uses the device and can perceive loud sounds. CONCLUSIONS: Cases where the use of tactile aids may make sense are probably very rare. The use of BCD, placed, e.g., at the wrist, may be useful, but sound perception is limited to low frequencies and relatively loud levels.

An intracochlear electrocochleography dataset - from raw data to objective analysis using deep learning.

Electrocochleography (ECochG) measures electrophysiological inner ear potentials in response to acoustic stimulation. These potentials reflect the state of the inner ear and provide important information about its residual function. For cochlear implant (CI) recipients, we can measure ECochG signals directly within the cochlea using the implant electrode. We are able to perform these recordings during and at any point after implantation. However, the analysis and interpretation of ECochG signals are not trivial. To assist the scientific community, we provide our intracochlear ECochG data set, which consists of 4,924 signals recorded from 46 ears with a cochlear implant. We collected data either immediately after electrode insertion or postoperatively in subjects with residual acoustic hearing. This data descriptor aims to provide the research community access to our comprehensive electrophysiological data set and algorithms. It includes all steps from raw data acquisition to signal processing and objective analysis using Deep Learning. In addition, we collected subject demographic data, hearing thresholds, subjective loudness levels, impedance telemetry, radiographic findings, and classification of ECochG signals.

Performance with a new bone conduction implant audio processor in patients with single-sided deafness.

PURPOSE: The SAMBA 2 BB audio processor for the BONEBRIDGE bone conduction implant features a new automatic listening environment detection to focus on target speech and to reduce interfering speech and background noises. The aim of this study was to evaluate the audiological benefit of the SAMBA 2 BB (AP2) and to compare it with its predecessor SAMBA BB (AP1). METHODS: Prospective within-subject comparison study. We compared the aided sound field hearing thresholds, speech understanding in quiet (Freiburg monosyllables), and speech understanding in noise (Oldenburg sentence test) with the AP1 and AP2. Each audio processor was worn for 2 weeks before assessment and seven users with single-sided sensorineural deafness (SSD) participated in the study. For speech understanding in noise, two complex noise scenarios with multiple noise sources including single talker interfering speech were used. The first scenario included speech presented from the front (S0NMIX), while in the second scenario speech was presented from the side of the implanted ear (SIPSINMIX). In addition, subjective evaluation using the SSQ12, APSQ, and the BBSS questionnaires was performed. RESULTS: We found improved speech understanding in quiet with the AP2 compared to the AP1 aided condition (on average + 17%, p = 0.007). In both noise scenarios, the AP2 lead to improved speech reception thresholds by 1.2 dB (S0NMIX, p = 0.032) and 2.1 dB (SIPSINMIX, p = 0.048) compared to the AP1. The questionnaires revealed no statistically significant differences, except an improved APSQ usability score with the AP2. CONCLUSION: Clinicians can expect that patients with SSD will benefit from the SAMBA 2 BB by improved speech understanding in both quiet and in complex noise scenarios, when compared to the older SAMBA BB.

Using a cochlear implant processor as contralateral routing of signals device in unilateral cochlear implant recipients.

PURPOSE: In unilateral cochlear implant (CI) recipients, a contralateral routing of signals (CROS) device enables to receive auditory information from the unaided side. This study investigates the feasibility as well as subjective and objective benefits of using a CI processor as a CROS device in unilateral CI recipients. METHODS: This is a single-center, prospective cohort study. First, we tested the directionality of the CROS processor in an acoustic chamber. Second, we examined the difference of speech perception in quiet and in noise in ten unilateral CI recipients with and without the CROS processor. Third, subjective ratings with the CROS processor were evaluated according to the Client Oriented Scale of Improvement Questionnaire. RESULTS: There was a time delay between the two devices of 3 ms. Connection of the CROS processor led to a summation effect of 3 dB as well as a more constant amplification along all azimuths. Speech perception in quiet showed an increased word recognition score at 50 dB (mean improvement 7%). In noise, the head shadow effect could be mitigated with significant gain in speech perception (mean improvement 8.4 dB). This advantage was reversed in unfavorable listening situations, where the CROS device considerably amplified the noise (mean: - 4.8 dB). Subjectively, patients who did not normally wear a hearing aid on the non-CI side were satisfied with the CROS device. CONCLUSIONS: The connection and synchronization of a CI processor as a CROS device is technically feasible and the signal processing strategies of the device can be exploited. In contra-laterally unaided patients, a subjective benefit can be achieved when wearing the CROS processor.

Influence of Compression Thresholds and Maximum Power Output on Speech Understanding with Bone-Anchored Hearing Systems.

Bone-anchored hearing systems (BAHS) transmit sound via osseointegrated implants behind the ear. They are used to treat patients with conductive or mixed hearing loss, but speech understanding may be limited especially in users with substantial additional cochlear hearing losses. In recent years, BAHS with higher maximum power output (MPO) and more advanced digital processing including loudness compression have become available. These features may be useful to increase speech understanding in users with mixed hearing loss. We have tested the effect of 4 combinations of two different MPO levels (highest level available and level reduced by 12 dB) and two different compression thresholds (CT) levels (50 dB and 65 dB sound pressure level) in 12 adult BAHS users on speech understanding in quiet and in noise. We have found that speech understanding in quiet was not influenced significantly by any of the changes in these two fitting parameters. In contrast, in users with average bone-conduction (BC) threshold of 25 dB or more, speech understanding in noise was improved by +0.8 dB to +1.1 dB (p < 0.03) when using the higher MPO level. In this user group, there may be an additional, but very small benefit of +0.1 dB to +0.4 dB when using the lower rather than the higher CT value, but the difference was not statistically significant (p > 0.27). In users with better average BC thresholds than 25 dB, none of the improvement was statistically significant. Higher MPOs and possibly, to a lesser degree, lower CTs seem to be able to improve speech understanding in noise in users with higher BC thresholds, but even their combined effect seems to be limited.

Effects of intensive care unit ambient sounds on healthcare professionals: results of an online survey and noise exposure in an experimental setting.

BACKGROUND: Noise levels on intensive care units (ICUs) are typically elevated. While many studies reported negative effects of ICU ambient sounds on patients, only few investigated noise as a factor to influence well-being or performance in healthcare professionals. METHODS: An online survey in the German-speaking part of Switzerland was conducted to assess how ICU soundscapes are subjectively perceived by healthcare professionals. The questionnaire was answered by 348 participants. Additionally, effects of noise on working memory performance were evaluated in an experimental noise exposure setting. Twenty-six healthcare professionals and 27 healthy controls performed a 2-back object-location task while being exposed to either ICU or pink noise. RESULTS: Survey results demonstrate that a majority of participants was aware of heightened noise levels. Participants reported that mostly well-being, performance, and attention could be reduced, along with subjective annoyance and fatigue by ICU ambient sounds. Although no significant effects of noise exposure on working memory performance was observed, self-assessments revealed significantly higher stress levels, increased annoyance and distraction ratings as well as decreased confidence in performance after ICU-noise exposure. CONCLUSION: Subjective assessments indicate that heightened noise levels on ICUs induce annoyance, with heightened stress levels, impaired well-being, and reduced performance being potential consequences. Empirical evidence with objective and physiological measures is warranted.

Influence of maximum power output on speech understanding with bone anchored hearing systems.

Background: Maximum power output (MPO) levels of bone anchored hearing systems (BAHS) vary between different devices, but are significantly lower than those of conventional hearing aids, potentially limiting speech understanding.Aims/objectives: To investigate, how MPO influences speech understanding in quiet and in noise in BAHS users.Materials and methods: 12 adult BAHS users with a bilateral conductive hearing loss and additional sensorineural hearing components between 4 and 45 dB (500-4000 Hz) participated in the study. Speech understanding was measured at 65 dB in quiet and in noise with 4 different MPO level settings, covering the approximate range of MPOs found in currently available BAHS devices.Results: Speech understanding in quiet and in noise decreased with increasing sensorineural hearing loss. MPOs levels did not influence speech understanding in quiet significantly. In contrast, speech understanding in noise was better with higher MPOs (average improvement in signal-to-noise ratio +3.2 dB, p < .001), but only if the sensorineural hearing loss component was above approximately 35 dB.Conclusions and significance: At normal conversational levels, higher MPOs have little or no influence on speech understanding in quiet with BAHS. However, they can improve speech understanding in noise for users with additional sensorineural hearing loss.

Speech Understanding and Sound Localization with a New Nonimplantable Wearing Option for Baha.

OBJECTIVE: To measure the audiological benefit of the Baha SoundArc, a recently introduced nonimplantable wearing option for bone conduction sound processor, and to compare it with the known softband wearing option in subjects with normal cochlear function and a purely conductive bilateral hearing loss. METHODS: Both ears of 15 normal hearing subjects were occluded for the time of the measurement, yielding an average unaided threshold of 49 dB HL (0.5 - 4 kHz). Soundfield thresholds, speech understanding in quiet and in noise, and sound localization were measured in unaided conditions and with 1 or 2 Baha 5 sound processors mounted on either a softband or a SoundArc device. RESULTS: Soundfield thresholds and speech reception thresholds were improved by 19.5 to 24.8 dB (p<.001), when compared to the unaided condition. Speech reception thresholds in noise were improved by 3.7 to 4.7 dB (p<.001). Using 2 sound processors rather than one improved speech understanding in noise for speech from the direction of the 2nd device and sound localization error by 23° to 28°. No statistically significant difference was found between the SoundArc and the softband wearing options in any of the tests. CONCLUSIONS: Bone conduction sound processor mounted on a SoundArc or on a softband resulted in considerable improvements in hearing and speech understanding in subjects with a simulated, purely conductive, and bilateral hearing loss. No significant difference between the 2 wearing options was found. Using 2 sound processors improves sound localization and speech understanding in noise in certain spatial settings.

Reliability of scapular kinematics estimated with three-dimensional motion analysis during shoulder elevation and flexion.

BACKGROUND: Knowing the reliability of three-dimensional motion analysis to evaluate scapular kinematics during upper limb movements is essential to plan further research dedicated to understanding scapulothoracic joint movements relative to the global shoulder motion. RESEARCH QUESTION: The aim of this study was to assess the intra-subject as well as intra- and interrater reliability of scapulothoracic joint angles during shoulder elevation in scapular plane and shoulder flexion. METHODS: Twenty healthy participants (26.6 ± 3.5 years) were asked to perform maximum shoulder elevation in scapular plane as well as shoulder flexion. Reliability was assessed using the intraclass correlation coefficient (ICC) and its 95% confidence interval of scapular kinematics (rotation, tilting, pro-retraction) at each degree of global motion (shoulder elevation or shoulder flexion) between 0° to 150°. RESULTS: ICCs above 0.60 were accepted as good indicators for reliability. Intra-subject reliability was found to be very high (>0.9 for most part) for all scapulothoracic joint angles during both movements. Intra- and interrater reliability also showed good reliability being above 0.60 for the most part (except scapula tilting during shoulder elevation). Scapular kinematics showed low reliability during the respective first 10° and 20° of shoulder elevation and shoulder flexion. Furthermore, decreasing reliability was found above 120° of shoulder elevation or flexion. SIGNIFICANCE: This study generally showed good to high levels of reliability in the range of interest (20-120°) in evaluating scapula kinematics in healthy adults during shoulder elevation and flexion; these results are important for future research providing a better understanding of scapular kinematics.

Unilateral and Bilateral Audiological Benefit With an Adhesively Attached, Noninvasive Bone Conduction Hearing System.

OBJECTIVE: To assess the audiological benefit of a noninvasive, adhesively attached bone conduction device (BCD1) in subjects with induced bilateral conductive hearing loss. Secondary objectives were to evaluate the additional benefit of bilateral fitting compared with unilateral fitting and to compare the outcomes with bone conduction devices attached to a softband (BCD2). STUDY DESIGN: Prospective nonrandomized crossover study. SETTING: Tertiary referral center. PATIENTS: Fifteen subjects with induced bilateral conductive hearing loss. MAIN OUTCOME MEASURES: Sound field thresholds, speech understanding in quiet and in multinoise were assessed in unaided, unilateral, and bilateral treatment conditions. In addition, sound localization was evaluated in uni- and bilateral treatment conditions. RESULTS: The outcomes of BCD1 and BCD2 were comparable. Sound field thresholds improved by 24.6 dB (BCD1) and 24.8 dB (BCD2) in the unilateral and 26.8 dB (BCD1) and 25.1 dB (BCD2) in the bilateral treatment condition. Speech reception thresholds (SRTs) in quiet improved by 20.0 dB (BCD1) and 21.7 dB (BCD2) in the unilateral and by 22.7 dB (BCD1) and 21.5 dB (BCD2) in the bilateral condition. If speech was presented from the front, SRTs in noise were improved by 3.6 dB and 4.2 dB (unilateral) and by 4.5 dB and 4.4 dB (bilateral) for BCD1 and BCD2, respectively. With speech presented from the unilateral side, SRTs were improved by 4.0 dB and 4.7 dB (unilateral) and 3.8 dB and 4.8 dB (bilateral) compared with the unaided situation. If noise was presented from the contralateral side, small differences (-0.6 dB and -0.1 dB) were observed. Bilateral fitting brought additional benefits for speech understanding in noise and sound localization. CONCLUSIONS: Both bone conduction devices seem to be a valid treatment for patients with conductive hearing loss and minor sensorineural hearing loss component.

Occupational kneeling and squatting: development and validation of an assessment method combining measurements and diaries.

OBJECTIVES: As knee-straining postures such as kneeling and squatting are known to be risk factors for knee disorders, there is a need for effective exposure assessment at the workplace. Therefore, the aim of this study was to develop a method to capture knee-straining postures for entire work shifts by combining measurement techniques with the information obtained from diaries, and thus avoiding measuring entire work shifts. This approach was applied to various occupational tasks to obtain an overview of typical exposure values in current specific occupations. METHODS: The analyses were carried out in the field using an ambulatory measuring system (CUELA) to assess posture combined with one-day self-reported occupational diaries describing the durations of various work tasks. In total, 242 work shifts were measured, representing 81 typical tasks from 16 professions. Knee-straining postures were analysed as daily time intervals for five different postures. The accuracy of the method was examined by comparing the results to measurements of entire work shifts. RESULTS: Unsupported kneeling was the most widely used knee posture in our sample (median 11.4 % per work shift), followed by supported kneeling (3.0 %), sitting on heels (1.1 %), squatting (0.7 %), and crawling (0.0 %). The daily time spent in knee-straining postures varied considerably, both between the individual occupations, within an occupation (e.g. parquet layers: 0.0-88.9 %), and to some extent even within a single task (e.g. preparation work of floor layers (22.0 ± 23.0 %). The applied measuring method for obtaining daily exposure to the knee has been proven valid and efficient randomly compared with whole-shift measurements (p = 0.27). CONCLUSIONS: The daily degree of postural exposure to the knee showed a huge variation within the analysed job categories and seemed to be dependent on the particular tasks performed. The results of this study may help to develop an exposure matrix with respect to occupational knee-straining postures. The tested combination of task-based measurement and diary information may be a promising option for providing a cost-effective assessment tool.