Assessment of Interaural Attenuation in Infants and Young Children Using Bone-Conducted Auditory Brainstem Response.

OBJECTIVES: In hearing assessment, the term interaural attenuation (IAA) is used to quantify the reduction in test signal intensity as it crosses from the side of the test ear to the nontest ear. In the auditory brainstem response (ABR) testing of infants and young children, the size of the IAA of bone-conducted (BC) stimuli is essential for the appropriate use of masking, which is needed for the accurate measurement of BC ABR thresholds. This study aimed to assess the IAA for BC ABR testing using 0.5 to 4 kHz narrowband (NB) CE-chirp LS stimuli in infants and toddlers with normal hearing from birth to three years of age and to examine the effects of age and frequency on IAA. DESIGN: A total of 55 infants and toddlers with normal hearing participated in the study. They were categorized into three age groups: the young group (n = 31, infants from birth to 3 mo), middle-aged group (n = 13, infants aged 3-12 mo), and older group (n = 11, toddlers aged 12-36 mo). The participants underwent BC ABR threshold measurements for NB CE-chirp LS stimuli at 0.5 to 4 kHz. For each participant, one ear was randomly defined as the "test ear" and the other as the "nontest ear." BC ABR thresholds were measured under two conditions. In both conditions, traces were recorded from the channel ipsilateral to the test ear, whereas masking was delivered to the nontest ear. In condition A, the bone oscillator was placed on the mastoid of the test ear, whereas in condition B, the bone oscillator was placed on the mastoid contralateral to the test ear. The difference between the thresholds obtained under conditions A and B was calculated to assess IAA. RESULTS: The means of IAA (and range) in the young age group for the frequencies 0.5, 1, 2, and 4 kHz were 5.38 (0-15) dB, 11.67 (0-30) dB, 21.15 (10-40) dB, and 23.53 (15-35) dB, respectively. Significant effects were observed for both age and frequency on BC IAA. BC IAA levels decreased with age from birth to 36 mo. In all age groups, smaller values were observed at lower frequencies and increased values were observed at higher frequencies. CONCLUSIONS: BC IAA levels were both age and frequency dependent. The study found that the BC IAA values for lower stimulus frequencies were smaller than previously assumed, even in infants younger than 3 mo. These results suggest that masking should be applied in BC ABR threshold assessments for NB CE-chirp LS stimuli at 0.5, 1, and 2 kHz, even in young infants. Masking may not be necessary for testing at 4 kHz if a clear response is obtained at 15 dB normal-hearing level (nHL) in infants younger than 3 mo.

Comparison of hearing performance in patients with borderline indication for active middle ear or cochlear implants: clinical outcomes to guide preoperative counseling and decision making.

PURPOSE: The aim of the presented study was to compare the audiological benefit achieved in cochlear implant (CI) patients who, in principle, could still have been treated with an active middle ear implant (AMEI) with a group of AMEI users. METHODS: Results of 20 CI patients with a pure-tone average (PTA) of 70 dB HL prior to surgery were compared with a group of 12 subjects treated with a Vibrant Soundbridge (VSB). Pre-surgical comparison included PTA for air conduction and bone conduction, maximum speech recognition score for monosyllabic words (WRSmax), and aided monosyllabic word recognition at 65 dB SPL. One year after surgery, aided monosyllabic speech recognition score at 65 dB SPL was compared. RESULTS: Mean PTA for air conduction in the VSB group was significantly lower than in the CI group (4.8 dB, Z = - 2.011, p < 0.05). Mean PTA for bone conduction in the VSB group was also significantly lower than in the CI group (23.4 dB, Z = - 4.673, p < 0.001). WRSmax in the VSB group was significantly better than in the CI group (40.7%, Z = - 3.705, p < 0.001). One year after treatment, there was no significant difference in aided speech perception in quiet between both subject groups. CONCLUSION: Comparison of the two methods showed equivalent results for both treatments in subjects with a borderline indication. Not only pure-tone audiometry results but, particularly, speech perception scores pre-surgery should be taken into account in preoperative counseling.

Evaluation of Hearing Functions in Children with Celiac Disease and the Effect of Gluten-free Diet on these Functions.

OBJECTIVE: The present study aims to investigate the potential impact of celiac disease (CD) on hearing functions and assess the effect of a gluten-free diet (GFD) on this condition. MATERIALS AND METHODS: The study included 55 children with CD (110 ears) and 25 healthy controls (50 ears) matched for age and gender. The CD group was divided into adherent (n = 31) and nonadherent (n = 24) to GFD. Participants underwent tympanometry and pure tone audiometry assessments covering frequencies from 500 to 4000 Hz. RESULTS: Patients with CD showed significantly higher air and bone conduction hearing averages compared to the control group at frequencies of 500, 1000, 2000, and 4000 Hz for air conduction, and at 500 Hz for bone conduction (P < 0.05). Celiac patients, those who fully adhered to GFD, had notably higher air conduction hearing averages at 500, 2000, and 4000 Hz compared to healthy controls (P < 0.05). However, there was no difference in bone conduction hearing averages between the two groups. In contrast, celiac patients who did not comply with GFD had statistically significantly higher air and bone conduction hearing averages than the control group (P < 0.05), at frequencies of 500, 1000, and 4000 Hz for air conduction, and at 500 and 1000 Hz for bone conduction (P < 0.05). CONCLUSIONS: The study suggests that nonadherence to GFD may elevate the risk of hearing loss in children with CD. As a result, it is recommended to conduct hearing screenings for children with CD and underscore the importance of complying with GFD to mitigate further detrimental effects on hearing functions.

Bone-Anchored Hearing Devices for Single-Sided Deafness: A New Preoperative Evaluation Protocol and Widening of Indications Proposal.

INTRODUCTION: Bone-anchored hearing devices (BAHD) are well-known good solution for single-sided deafness (SSD). Despite power extension of recently introduced BAHD with implanted active transducer, with indications up to 65 dB Hl of bone conduction (BC) threshold on the implanted side, their indications for SSD still remain better than 25 dB on the good ear, with regards to bone conduction thresholds. The aim of this study was to assess the possibility to enlarge BAHD indications for SSD by means of a newly proposed candidacy evaluation protocol, which includes a new software-aided method. METHODS: 20 SSD patients (mean age 56 years, 9 females, and 11 males) were divided into two groups: group A (10 patients, BC <25 dB Hl on the hearing side) and group B (10 patients, BC between 25 and 35 dB Hl). Recipients were submitted to bisyllabic words speech audiometry in silence and to authors' newly proposed IFastSRT50 test by means of software which shift noise intensity of a single word list on the basis of correct recipient recognition responses. A sound speaker for signal (bisyllabic words) and noise (babble) was disposed at 1 m from the deaf side of the patient. An earphone covering only the good ear of the recipient was used in order to perform its air conduction masking with white noise. A BAHD test device was disposed on the mastoid of the deaf side. Both signal and masking intensities were set to 55 dB SPL in order to mask airway conduction on the good ear without masking its bone way interaural conduction from the BAHD tester. RESULTS: With BAHD tester turned off, no recognition was detected. Speech audiometry with BAHD tester turned on revealed mean values of 92% for group A and 89% for group B, with a difference of 3.0% (χ2 = 0.285 and p = 0.5935). As for IFastSRT50 with BAHD tester turned on, mean signal-to-noise ratio value to obtain 50% of recognition was -6.89 for group A and -6, with a difference of 0.89 (t = 1,201 and p = 0.2453). CONCLUSION: BAHD are confirmed to be a good solution for SSD cases. The absence of statistically significant differences in our two tested groups suggests that newer implanted active transducer device indications should be extended up to 35 dB Hl on the hearing ear. The IFastSRT50 is a reliable and quick method to enhance preoperative candidacy evaluation.

A novel method for objective in-situ measurement of audibility in bone conduction hearing devices - a pilot study using a skin drive BCD.

OBJECTIVE: Objective measurement of audibility (verification) using bone conduction devices (BCDs) has long remained an elusive problem for BCDs. For air conduction hearing aids there are well-defined and often used objective methods, and the aim of this study is to develop an objective method for BCDs. DESIGN: In a novel setup for audibility measurements of bone-anchored hearing aid (BAHA) attached via a soft band, we used a skin microphone (SM) on the forehead measuring in-situ sound field thresholds, maximum power output (MPO) and international speech test signal (ISTS) responses. STUDY SAMPLE: Five normal-hearing persons. RESULT: Using the electrical output of SM it was possible to objectively measure the audibility of a skin drive BCD, presented as an eSPL-o-gram showing thresholds, MPO and ISTS response. Normalised eSPL-o-gram was verified against corresponding FL-o-grams (corresponding force levels from skull simulator and artificial mastoid (AM)). CONCLUSION: The proposed method with the SM can be used for objective measurements of the audibility of any BCDs based on thresholds, MPO and speech response allowing for direct comparisons of hearing and BCD output on the same graph using an eSPL-o-gram. After normalisation to hearing thresholds, the audibility can be assessed without the need for complicated calibration procedures.

Differing Bilateral Benefits for Spatial Release From Masking and Sound Localization Accuracy Using Bone Conduction Devices.

OBJECTIVES: Normal binaural hearing facilitates spatial hearing and therefore many everyday listening tasks, such as understanding speech against a backdrop of competing sounds originating from various locations, and localization of sounds. For stimulation with bone conduction hearing devices (BCD), used to alleviate conductive hearing losses, limited transcranial attenuation results in cross-stimulation so that both cochleae are stimulated from the position of the bone conduction transducer. As such, interaural time and level differences, hallmarks of binaural hearing, are unpredictable at the level of the inner ears. The aim of this study was to compare spatial hearing by unilateral and bilateral BCD stimulation in normal-hearing listeners with simulated bilateral conductive hearing loss. DESIGN: Bilateral conductive hearing loss was reversibly induced in 25 subjects (mean age = 28.5 years) with air conduction and bone conduction (BC) pure-tone averages across 0.5, 1, 2, and 4 kHz (PTA 4 ) <5 dB HL. The mean (SD) PTA 4 for the simulated conductive hearing loss was 48.2 dB (3.8 dB). Subjects participated in a speech-in-speech task and a horizontal sound localization task in a within-subject repeated measures design (unilateral and bilateral bone conduction stimulation) using Baha 5 clinical sound processors on a softband. For the speech-in-speech task, the main outcome measure was the threshold for 40% correct speech recognition when masking speech and target speech were both colocated (0°) and spatially and symmetrically separated (target 0°, maskers ±30° and ±150°). Spatial release from masking was quantified as the difference between colocated and separated masking and target speech thresholds. For the localization task, the main outcome measure was the overall variance in localization accuracy quantified as an error index (0.0 = perfect performance; 1.0 = random performance). Four stimuli providing various spatial cues were used in the sound localization task. RESULTS: The bilateral BCD benefit for recognition thresholds of speech in competing speech was statistically significant but small regardless if the masking speech signals were colocated with, or spatially and symmetrically separated from, the target speech. Spatial release from masking was identical for unilateral and bilateral conditions, and significantly different from zero. A distinct bilateral BCD sound localization benefit existed but varied in magnitude across stimuli. The smallest benefit occurred for a low-frequency stimulus (octave-filtered noise, CF = 0.5 kHz), and the largest benefit occurred for unmodulated broadband and narrowband (octave-filtered noise, CF = 4.0 kHz) stimuli. Sound localization by unilateral BCD was poor across stimuli. CONCLUSIONS: Results suggest that the well-known transcranial transmission of BC sound affects bilateral BCD benefits for spatial processing of sound in differing ways. Results further suggest that patients with bilateral conductive hearing loss and BC thresholds within the normal range may benefit from a bilateral fitting of BCD, particularly for horizontal localization of sounds.

Wave propagation across the skull under bone conduction: Dependence on coupling methods.

This study is aimed at the quantitative investigation of wave propagation through the skull bone and its dependence on different coupling methods of the bone conduction hearing aid (BCHA). Experiments were conducted on five Thiel embalmed whole head cadaver specimens. An electromagnetic actuator from a commercial BCHA was mounted on a 5-Newton steel headband, at the mastoid, on a percutaneously implanted screw (Baha® Connect), and transcutaneously with a Baha® Attract (Cochlear Limited, Sydney, Australia), at the clinical bone anchored hearing aid (BAHA) location. Surface motion was quantified by sequentially measuring ∼200 points on the skull surface via a three-dimensional laser Doppler vibrometer (3D LDV) system. The experimental procedure was repeated virtually, using a modified LiUHead finite element model (FEM). Both experiential and FEM methods showed an onset of deformations; first near the stimulation area, at 250-500 Hz, which then extended to the inferior ipsilateral skull surface, at 0.5-2 kHz, and spread across the whole skull above 3-4 kHz. Overall, stiffer coupling (Connect versus Headband), applied at a location with lower mechanical stiffness (the BAHA location versus mastoid), led to a faster transition and lower transition frequency to local deformations and wave motion. This behaviour was more evident at the BAHA location, as the mastoid was more agnostic to coupling condition.

The sensitivity of bone conduction for dental implants.

Dental implants are connected to the alveolar bone by osseointegration. Dental implants could be used as a potential bone conduction (BC) hearing assistive device in the mouth. However, the BC threshold of dental implants has not been reported. The present study aimed to examine the pure tone auditory thresholds of normal human subjects to BC stimulation of the implants. Dental implants showed a significantly lower BC threshold than natural teeth and mastoids. Mandibular dental implants had BC sensitivity similar to that of maxillary dental implants. The BC threshold of anterior dental implants was significantly lower than that of posterior dental implants. Dental implants exhibited excellent BC properties.

Measurement and modeling of the mechanical impedance of human mastoid and condyle.

Bone conduction devices are used in audiometric tests, hearing rehabilitation, and communication systems. The mechanical impedance of the stimulated skull location affects the performance of the bone conduction devices. In the present study, the mechanical impedances of the mastoid and condyle were measured in 100 Chinese subjects aged from 22 to 67 years. The results show that the mastoid and condyle impedances within the same subject differ significantly and the impedance differences between subjects at the same stimulation position are mainly below the resonance frequency. The mechanical impedance of the mastoid is significantly influenced by age, and not related to gender or body mass index (BMI). While the mechanical impedance of the condyle is significantly affected by BMI, followed by gender, and not related to age. There are some differences in mastoid impedance between the Chinese and Western subjects. An analogy model predicts that the difference in mechanical impedance between the mastoid and condyle leads to a significant difference in the output force of the bone conduction devices. The results can be used to develop improved condyle and mastoid stimulators for the Chinese.

Transcutaneous and percutaneous bone conduction sound propagation in single-sided deaf patients and cadaveric heads.

OBJECTIVE: To investigate transcranial transmission (TT) and the dampening effect of the skin in patients and cadaver heads. DESIGN: In patients a pure tone bone conduction audiogram for ipsilateral and contralateral stimulation was performed. The TT was defined as the difference between ipsilateral and contralateral hearing thresholds. In cadaver heads ipsilateral and contralateral promontory motion was measured using a three-dimensional Laser Doppler Vibrometer system. STUDY SAMPLE: Seven single-sided deaf patients fitted with a Baha® Connect, fifteen single-sided deaf patients without a bone conduction hearing aid and five Thiel-embalmed cadaver heads were included. RESULTS: The TT decreased with increasing frequency in patients and cadaver heads. No significant difference was seen between patients and cadaver heads. Measurements on patients and cadaver heads showed increasing skin attenuation with increasing frequency. However, the dampening effect was 3-12 dB higher in patients than in cadavers at all frequencies. CONCLUSION: The TT was not significantly different for patients compared to cadaver heads. The value of promontory motion to estimate TT in patients need to be further evaluated. The skin attenuates a BC stimulus by 10-20 dB in patients and by a smaller amount in cadaver heads, probably due to changes in the properties of the Thiel-conserved skin.

miR-210 regulates the inflammation of otitis media with effusion by inhibiting the expression of hypoxia-inducible factor (HIF)-1a.

Otitis media with effusion (OME) is the major cause of hearing impairment in children. miR-210 plays a critical role in inflammatory diseases, however, its role in OME is unknown. In this study, the miR-210 level in serum and middle ear effusion of is significantly down-regulated in serum, middle ear effusion from OME patients (100 cases) compared with healthy volunteers (50 cases). The expression of miR-210 is closely related to inflammatory factors and bone conduction disorder in patients with OME. In the in vitro study，the miR-210 level is significantly reduced in culture supernatant of lipopolysaccharide (LPS) treated human middle ear epithelial cells (HMEECs). miR-210 overexpression inhibited the LPS-induced in inflammatory cytokines production, cell viability reduction and cell apoptosis. Bioinformatics and dual-luciferase reporter assay showed that HIF-1a was a target gene of miR-210. The biological effects of miR-210 on cell viability, cell apoptosis and inflammation cytokines in LPS-induced HMEECs were reversed by HIF-1a overexpression. Furthermore, phosphorylation of NF-κB p65 was significantly decreased by miR-210 mediated HIF-1a in LPS-induced HMEECs. This study suggested that miR-210 may play a role in OME. Further studies are warranted to assess miR-210 as a potential target for the diagnosis and treatment of OME.

Effectiveness of Bone Conduction Hearing Aids in Young Children with Congenital Aural Atresia and Microtia.

BACKGROUND The aim of this study was to assess the effectiveness of bone conduction hearing aids in children under 2 years old who have congenital microtia and atresia. MATERIAL AND METHODS This prospective study involved 42 children under 2 years old with congenital microtia and atresia who were divided into 2 groups: 21 with unilateral defect and 21 with bilateral defect. All children were provided with bone conduction hearing aids on a softband. Air and bone auditory thresholds were assessed by auditory brainstem responses (ABRs). The LittlEARS questionnaire was used to evaluate auditory development at baseline and after 6 months of hearing aids use. Behavioral observation audiometry (BOA) was used to assess auditory thresholds and compare aided and unaided hearing. RESULTS After 6 months of hearing aid use, the total score of the LittlEARS questionnaire in children with unilateral defect was 24±5.60, while children with bilateral defect achieved a result of 26.29±6.17. Hearing thresholds in both groups with bone conduction hearing aids improved significantly and approached the normal level. CONCLUSIONS Our results confirm that bone conduction hearing aids provide an effective method of auditory rehabilitation for children with conductive and mixed hearing loss caused by microtia and atresia. Using bone conduction hearing aids in such children is crucial for proper hearing, speech, and language development.

Effects of tympanic membrane perforation, middle ear cavity volume, and mastoid aeration on hearing impairment.

AIMS: To investigate the effects of the location and size of tympanic membrane (TM) perforation and middle ear cavity volume on conductive hearing loss in patients with TM perforation. METHODS: Data were collected via a retrospective medical chart review. RESULTS: We enrolled 128 patients with a mean age of 45.6 ± 10.1 years. The mean perforation size was 21.2 ± 8.6% of the TM area, and the mean air-bone gap (ABG) was 20.2 ± 8.6 dB HL on pure tone audiometry. Patients were divided into two groups based on mean ABG. Patients with a large ABG had a significantly larger TM perforation area and smaller mastoid volume. The TM perforation was most commonly located in the central section. However, regression analyses showed that the proportion of the perforated TM area was the only independent predictor of a large ABG (odds ratio, 1.053; 95% confidence interval, 1.022-1.085; p = 0.001). When we analyzed the frequencies in which hearing loss occurred due to TM perforation, we confirmed that hearing loss occurred mainly in the low-frequency range. CONCLUSION: In patients with TM perforation, conductive hearing loss occurs mainly at low frequencies and in proportion to the size of the TM perforation.

Early Osia® 2 bone conduction hearing implant experience: Nationwide controlled-market release data and single-center outcomes.

PURPOSE: Bone conduction hearing devices are a well-established treatment option for conductive or mixed hearing losses as well as single-sided deafness. The Osia® 2 System is an active osseointegrated device where a surgically implanted titanium fixture supports a newly developed piezoelectric actuator that is placed under the skin. METHODS: Nationwide data collected during a controlled-market release (CMR) of the Cochlear™ Osia® 2 System as well as outcomes at single, tertiary-level private practice Otology/Neurotology center were retrospectively reviewed. Key learnings from surgeons and audiologists are discussed. RESULTS: During the CMR period, 23 surgeons performed 44 operations on 43 recipients. The mean age of recipients was 44 years and mean surgery duration was 52 min. The most commonly used incision was postauricular but anterior to the device (78%). Five complications were observed during the CMR, none of which were device related. Twenty-one audiologists performed 33 Osia® 2 activations during the CMR. The mean age of this group was 47 years, and the mean duration of each activation appointment was 55 min. Single-center data at the authors' institution demonstrated an average additional PTA4 gain with the Osia® 2 patients of 9.6 dB compared to Baha Attract and 10.2 dB compared to Baha Connect. CONCLUSION: The Cochlear™ Osia® 2 System represents a significant advance in auditory osseointegrated implant technology. Digital piezoelectric stimulation delivers high power outputs, improves high frequency gain for optimal speech perception, and maintains safety while providing excellent patient satisfaction.

Bone-conducted vestibular and stretch reflexes in human neck muscles.

In normal humans, tapping the forehead produces a neck muscle reflex that is used clinically to test vestibular function, the cervical vestibular evoked myogenic potential (cVEMP). As stretch receptors can also be activated by skull taps, we investigated the origin of the early and late peaks of the bone-conducted cVEMP. In twelve normal participants, we differentially stimulated the vestibular and neck stretch receptors by applying vibration to the forehead (activating both vestibular and stretch receptors) and to the sternum (activating mainly stretch receptors). Patients with bilateral vestibulopathy (BVP; n = 26) and unilateral vestibular loss (uVL; n = 17) were also investigated for comparison. Comparison of peaks in normal subjects suggested that the early peaks were vestibular-dependent, while the later peaks had mixed vestibular and stretch input. The late peaks were present but small (1.1 amplitude ratio) in patients with BVP and absent VEMPs, confirming that they do not strictly depend on vestibular function, and largest in age-matched controls (1.5 amplitude ratio, p = 0.049), suggesting that there is an additional vestibular reflex at this latency (approx. 30 ms). Patients with uVL had larger late peaks on the affected than the normal side (1.4 vs 1.0 amplitude ratio, p = 0.034). The results suggest that the early responses in SCM to skull vibration in humans are vestibular-dependent, while there is a late stretch reflex bilaterally and a late vestibular reflex in the contralateral muscle.

Mapping the vestibular cerebellar evoked potential (VsCEP) following air- and bone-conducted vestibular stimulation.

Vestibular cerebellar evoked potentials (VsCEPs) were recorded from over the occipital and cerebellar regions of the scalp using bone-conducted (BC) stimuli applied at the mastoids (impulsive accelerations and 500 Hz) and 500 Hz acoustic tones (AC). Ten healthy subjects were tested. Electrodes were positioned over the midline (Oz, Iz, CBz) and at 3, 6 and 9 cm intervals lateral to the midline electrodes bilaterally. Additional electrodes were also positioned over posterior neck muscles (SPL1 and SPL2). The largest evoked potentials on average were recorded from the electrodes 3 and 6 cm lateral to the Iz and CBz midline locations. BC stimuli produced short latency potentials on the side contralateral to the stimulated mastoid and were dependent on stimulus polarity. Positive polarity stimuli produced biphasic VsCEPs at approximately 12 and 17 ms (P12-N17) for BC impulses and 10 and 15 ms (P10-N15) for BC 500 Hz stimuli. Following the initial excitation, there was a period of suppression of background activity lasting an average of 16.8 ms for positive polarity BC impulses. Negative polarity stimuli produced later VsCEPs both for BC impulses (P20-N26) and BC 500 Hz (P13-N18). VsCEPs to AC 500 Hz stimuli lateralised to the contralateral side and were larger for right than left ear stimulation. Stimulus polarity (condensation and rarefaction) did not alter the timing of the VsCEPs to AC 500 Hz tones. No evoked response was recorded to somatosensory (median and radial nerve) stimulation. Four patients with cerebellar disease were tested and two showed abnormal VsCEPs with initial negativities. VsCEPs show distinct mapping over the posterior fossa and are likely to reflect climbing fibre responses via crossed otolith-cerebellar pathways.

Effectiveness of Bone Conduction Stimulation Applied Directly to the Otic Capsule Measured at Promontory: Assessment in Cadavers.

INTRODUCTION: The aims of this study included: (a) to develop a method of direct acoustic bone conduction (BC) stimulation applied directly to the otic capsule, (b) to investigate the effect of different stimulation sites on the promontory displacement amplitude, and (c) to find the best stimulation site (among 2 located directly on the otic capsule and 1 standard site approved for clinical use) that provides the greatest transmission of vibratory energy. METHODS: Measurements were performed on 9 cadaveric whole human heads. A commercial scanning laser Doppler vibrometer was used. The promontory displacement was recorded in response to BC stimulation delivered by an implant at 3 sites: BC1 on the squamous part of the temporal bone, BC2 on the ampulla of the lateral semicircular canal, and BC3 between the semicircular canals. The displacement of the promontory was analyzed in detail. RESULTS: The results show that BC1 caused an overall smaller promontory displacement than both sites BC2 and 3. BC3 stimulation is more efficient than that at BC2. CONCLUSIONS: BC is an effective method of acoustic stimulus delivery into the inner ear, with the effectiveness increasing when approaching closer to the cochlea. Placing the implant directly on the labyrinth and thus applying vibrations directly to the otic capsule is possible and very effective as proved in this study. The results are encouraging and represent the potential of new stimulation sites that could be introduced in the field of BC hearing rehabilitation as the possible future locations for implantable BC hearing devices.

Bone Conduction Trial Device to Eliminate the Effect of Transcranial Attenuation: A Prospective Observational Study in Single-Sided Deaf Subjects.

OBJECTIVES: The contact miniTM (CM) is a nonimplantable, digital bone conduction device (BCD) consisting of 2 isolated units: an electronic housing, including the microphone, and a vibrator housing. The study investigated whether the CM can be used as an alternative test device for a BCD trial in single-sided deaf (SSD) adults with the microphone placed at the SSD ear and the vibrator at the normal-hearing (NH) ear (i.e., cross position). METHODS: Twenty SSD adults (mean age: 50 [±13.2] years) participated in a 2-week BCD trial with the CM on the headband in cross position. Prior to the trial, the subjects performed adaptive speech-in-noise tests in an unaided condition. After the trial, speech-in-noise tests were performed with the CM in cross position (CMcross) and ipsilateral position, i.e., both units at the SSD ear (CMipsi). Five different speech-in-noise configurations were used (S0N0; S0NNH; S0NSSD; S0°NNH+SSD; and SSSDNNH). Speech reception thresholds (SRT) were analyzed comparing the unaided, the CMcross condition, and the CMipsi condition. RESULTS: Friedman's test revealed no significant differences in SRTs between the CMcross, CMipsi, and the unaided condition for the S0N0, S0NNH, S0NSSD, and S0°NNH+SSD configuration. However, in the SSSDNNH configuration, a significant effect was found (p < 0.001). Wilcoxon pairwise comparisons with Bonferroni correction indicated that SRTs in the CMcross condition were significantly lower (i.e., better speech understanding) than those in the unaided (p < 0.001) and the CMipsi condition (p < 0.05). CONCLUSION: The CM may be a good alternative for patients with SSD, resulting in significantly better speech recognition when noise is presented to the NH ear and speech to the SSD ear. As the speech recognition results are better in the cross than the ipsilateral position, the CMcross might help to overcome the negative effect of transcranial attenuation during BCD trials.

Audiological Results with the SAMBA Audio Processor in Comparison to the Amadé for the Vibrant Soundbridge.

BACKGROUND: Since its introduction in 1996, the Vibrant Soundbridge (VSB) has been upgraded with several improved generations of processors. As all systems are compatible, implanted patients can benefit from new technologies by upgrading to the newest processor type available. OBJECTIVES: The aim of this study was to compare the performance of the new (current) SAMBA processor with the previous Amadé processor. METHODS: Twenty subjects monaurally implanted with a VSB and the Amadé processor tested the new SAMBA processor for a trial period of 4 weeks. We measured air conduction and bone conduction thresholds, unaided thresholds, and aided free field thresholds with both devices. Speech performance in quiet using the Freiburg monosyllabic test at 65 dB SPL (S0) was compared. The speech intelligibility in noise was determined using the Oldenburg sentence test measured in different listening conditions (S0NVSB/S0Ncontra) and microphone settings (omni/directional vs. adaptive directivity). RESULTS: Word recognition scores in quiet with the SAMBA were still significantly lower than with the Amadé after the 4 weeks trial period but improved over the following year. Speech intelligibility with the SAMBA was significantly better than with the Amadé in omnidirectional mode and comparable with the Amadé in directional mode. Hence, the adaptive directionality provides an advantage in difficult hearing situations such as noisy environments. The subjective benefit was evaluated using the Abbreviated Profile of Hearing Aid Benefit and the Speech, Spatial and Qualities-C questionnaire. Results of the questionnaires demonstrate an overall higher level of satisfaction with the new SAMBA speech processor than with the older processor. CONCLUSION: The SAMBA enables similar speech perception in quiet but more flexible adaptation in acoustically challenging environments compared to the previous Amadé processor.

The vibrating ossicular prosthesis in children and adolescents: a retrospective study.

PURPOSE: The primary objective of the retrospective study was to collect speech intelligibility data on children and adolescents implanted with the vibrating ossicular prosthesis (VORP) 503. METHODS: This was a retrospective, multicentre study on 55 children and adolescents from 6 German clinics aged between 5 and 17 years suffering from mixed or conductive hearing loss implanted with a VORP 503. Pre- and postoperative bone-conduction pure tone thresholds were measured at 0.5, 1, 2 and 4 kHz, and word recognition scores in the unaided and VORP 503-aided conditions using monosyllabic speech intelligibility tests measured at 65-dB sound pressure level (SPL) were determined. RESULTS: Mean pre- and postoperative bone-conduction thresholds remained unchanged, showing the preservation of inner ear hearing. Speech intelligibility assessed in quiet at 65-dB SPL improved on average from 24.5% (SD ± 25.4) unaided to 86.4% (SD ± 13.4) aided. The average improvement of 61.9% (SD ± 25.3) was clinically and statistically significant. A total of three complications were found in the medical records of 55 subjects. The responsible investigators judged these events as procedure related. CONCLUSION: The treatment of children suffering from conductive or mixed hearing loss with the VORP 503 implant demonstrates excellent aided benefit in terms of speech understanding and only minor complications.