Percutaneous Bone Conduction Devices Research Articles

Tissue Classification After Bone-Anchored Hearing Implant Surgery: A Machine Learning Approach to Monitoring Skin Response.

Here, we aim to 1) expand the available evidence for the use of machine learning techniques for soft tissue classification after BCD surgery and 2) discuss the implications of such approaches toward the development of classification applications to aid in tissue monitoring. The application of machine learning techniques in the soft tissue literature has become a large field of study. One of the most commonly reported outcomes after percutaneous bone-conduction device (BCD) surgery is soft tissue health. Unfortunately, the classification of tissue around the abutment as healthy versus not healthy is a subjective process, even though such decisions can have implications for treatment (i.e., topical steroid versus surgical revision) and resources (e.g., clinician time). We built and tested a convolutional neural network (CNN) model for the classification of tissues that were rated as "green" (i.e., healthy), "yellow" (i.e., unhealthy minor), and "red" (i.e., unhealthy severe). Representative image samples were gathered from a regional bone-conduction amplification site (N = 398; 181 samples of green; 144 samples of yellow; 73 samples of red). The image samples were cropped, zoomed, and normalized. Feature extraction was then implemented and used as the input to train an advanced CNN model. Accuracy of image classification for the healthy ("green") versus not healthy ("yellow" and "red") model was approximately 87%. Accuracy of image classification for the unhealthy ("yellow") versus unhealthy ("red") model was approximately 94%. Monitoring tissue health is an ongoing challenge for BCD users and their clinicians not trained in soft tissue management (e.g., audiologists). If machine learning can aid in the classification of tissue health, this would have significant implications for stakeholders. Here we discuss how machine learning can be applied to tissue classification as a potential technological aid in the coming years.

Post-implantation clinical cost analysis between transcutaneous and percutaneous bone conduction devices

IntroductionBone conduction devices (BCD) are effective for hearing rehabilitation in patients with conductive and mixed hearing loss or single-sided deafness. Transcutaneous bone conduction devices (tBCD) seem to lead to fewer soft tissue complications than percutaneous BCDs (pBCD) but have other drawbacks such as MRI incompatibility and higher costs. Previous cost analyses have shown a cost advantage of tBCDs. The purpose of this study is to compare long-term post-implantations costs between percutaneous and transcutaneous BCDs.Materials and methodsRetrospective data from 77 patients implanted in a tertiary referral centre with a pBCD (n = 34), tBCD (n = 43; passive (tpasBCD; n = 34) and active (tactBCD; n = 9) and a reference group who underwent cochlear implantation (CI; n = 34), were included in a clinical cost analysis. Post-implantation costs were determined as the sum of consultation (medical and audiological) and additional (all post-operative care) costs. Median (cumulative) costs per device incurred for the different cohorts were compared at 1, 3 and 5 years after implantation.ResultsAfter 5 years, the total post-implantation costs of the pBCD vs tpasBCD were not significantly different (€1550.7 [IQR 1174.6–2797.4] vs €2266.9 [IQR 1314.1–3535.3], p = 0.185), nor was there a significant difference between pBCD vs tactBCD (€1550.7 [1174.6–2797.4] vs €1428.8 [1277.3–1760.4], p = 0.550). Additional post-implantation costs were significantly highest in the tpasBCD cohort at all moments of follow-up.ConclusionTotal costs related to post-operative rehabilitation and treatments are comparable between percutaneous and transcutaneous BCDs up to 5 years after implantation. Complications related to passive transcutaneous bone conduction devices appeared significantly more expensive after implantation due to more frequent explantations.

Ten-year retrospective evaluation of therapeutic choices and related satisfaction in patients with auricular deformities

To adequately counsel future patients with auricular abnormalities, this study aimed to analyze the therapeutic choices patients make after consultation concerning their auricle and/or hearing. All patients who visited the auricle consultation between January 2010 and January 2020 were included. This comprises patients with all types of auricular anomalies of both congenital and acquired etiology. Follow-up was performed by telephone to obtain informed consent and to take a short nonvalidated questionnaire regarding their therapeutic choices and satisfaction with these choices. Patient characteristics and information regarding therapeutic choices after consultation were subsequently obtained from the patients' medical files. The main outcome parameters were the patients’ therapeutic choices regarding the auricle and hearing. A total of 134 patients (61.2%) were included with a mean follow-up of 3.85 years. For congenital and acquired etiologies, 72.8% and 18.2% declined reconstruction, 14.0% and 18.2% chose autologous, 5.3% and 0% chose alloplastic, 6.1% and 45.4% chose prosthetic, and 1.8% and 18.2% chose another type of reconstruction, respectively. A total of 54.9% declined hearing rehabilitation, while 38.2% chose percutaneous bone conduction device (BCD), 2.0% transcutaneous BCD, and 4.9% BCD on a softband. The overall satisfaction score was 8.7/10 concerning the auricle and 8.3/10 regarding hearing. In conclusion, most patients with a congenital etiology chose to wait or decided against auricular reconstruction, while patients with acquired etiologies mostly opted for reconstruction by a prosthesis. Patients or their caregivers were very satisfied with their choice, regardless of whether this implies reconstruction or no reconstruction, which emphasizes the importance of shared decision-making and thorough counseling.

NAL-NL2 Prescriptive Targets for Bone Conduction Devices With an Adaptation to Device Constraints in the Low Frequencies.

Objectives:To study the effectivity of a transformed NAL non-linear version 2 (NAL-NL2) gain prescription for percutaneous bone conduction devices (BCDs) and to investigate how to take into account output constraints for the lower frequencies.Design:The NAL-NL2 prescription was converted to a bone conduction prescription rule. Adaptations were needed, as this converted rule prescribes more output at low frequencies than the device delivers. Three adaptations with different audibility and compression were compared. Setting 1 (S1, “optimal audibility”) had most audibility due to adapted frequency-dependent compression, setting 2 (S2, “moderate audibility”) had moderate output reduction below 1 kHz, and setting 3 (S3, “reduced audibility, least distortion”) had most output reduction. Eighteen experienced BCD users rated their relative sound quality in paired comparisons for different sounds (own voice, mixed voices, traffic noise, and music). In addition speech intelligibility in quiet and noise were assessed.Results:The relative sound quality rating for the adapted prescriptions varied between the stimuli: more low-frequency sound was preferred for music (S1 over S3), and less low-frequency sound was preferred for the own voice (S2 and S3 over S1). No differences in quality rating were found for mixed voices or traffic noise. Speech intelligibility in quiet scores at 45 dB SPL was significantly lower for S3 than for S1. Speech intelligibility in noise was significantly reduced in all settings and S3 yielded significantly better speech intelligibility in noise than S1.Conclusions:With a moderate gain reduction for low frequencies to comply with device constraints the transformed NAL-NL2 prescription was found suitable for fitting BCDs. Perceived sound quality depended on the gain settings, but also on the sound spectra and how the sound was appreciated. A moderate gain reduction below 1 kHz seems to be the optimal adaptation as it has a neutral or positive relative sound quality for all stimuli without negative effects on Speech intelligibility. The NAL-NL2-BC prescribed a sufficient amount of gain, as indicated by the speech tests.

The Minimally Invasive Star-Shaped Incision Technique and the Linear Incision Technique With Tissue Preservation for Percutaneous Bone Conduction Devices: A Retrospective Cohort Study.

PurposeTo compare intra- and postoperative outcomes between the standard linear incision technique with tissue preservation (LITT-P) and the minimally invasive star-shaped incision (SSI).Study DesignA retrospective cohort study.MethodsPrimary outcomes evaluated operative time, implant survival, and intra-operative complications. A secondary outcome evaluated soft tissue tolerability assessed by the Holger's classification.ResultsA total of 38 implants were placed (19 LITT-P; 19 SSI). The median and mean surgical duration for the LITT-P group was statistically shorter than the SSI group (p = 0.0001). No intra-operative complications were reported for both surgical approaches. Five implants were lost during postoperative follow-up: one in the LITT-P and four in the SSI cohort. Both cohorts showed favorable soft tissue tolerability. Less Holgers 1 and 2 and more Holgers 3 soft tissue reactions were observed after the LITT-P compared to the SSI.ConclusionThe novel SSI approach could be an alternative option based on the theoretical benefits and found favorable (and similar) soft tissue outcomes. Implant loss and surgical time are aspects to investigate regarding long-term durability and warrant further research.

Ex vivo Evaluation of a New Drill System for Placement of Percutaneous Bone Conduction Devices.

The procedure for installation of a percutaneous bone-conducting device has undergone significant improvements since its introduction 40 years ago. Today, the linear incision technique with tissue preservation (LITT-P) and the minimally invasive procedure (MIPS) are the most commonly used approaches. In both these techniques, a gradual increase of the osteotomy using a three-step drilling sequence is utilized, as this approach can allow a stepwise deepening and widening of the osteotomy in the mastoid and can prevent bone overheating. A new minimally invasive procedure (MONO) has been developed that allows an osteotomy to be performed and enables complete removal of the bone volume in one single drill step for a 4 mm implant using a novel parabolic twist drill. Here, the feasibility of the MONO procedure was qualitatively and quantitatively evaluated in terms of the dura response to drill trauma in comparison with the outcomes achieved with guide drills used for the LITT-P and MIPS techniques. Fresh frozen temporal bone from a human cadaver was subjected to penetration by three drills beyond the base of the mastoid bone to different depths. The sites were evaluated, and the damage to and possible penetration of the dura were determined. The results showed that for a drill depth exceeding mastoid bone thickness by not more than 1 mm, damage to the dura was limited or nonexistent, whereas for a drill depth exceeding bone thickness by 2 mm, damage increased, or the dura was penetrated. There was a trend toward more damage and penetration for both the round burr and MIPS guide drill compared with the MONO drill bit. From this experimental ex vivo study, it can be concluded that if the dura is encountered, the MONO system is not more inclined to penetrate the dura than the conventional LITT-P and MIPS systems.

Hearing-Related Quality of Life in 75 Patients With a Percutaneous Bone Conduction Device.

Objective:To evaluate long-term hearing-related quality of life (HRQoL) and device use in bone conduction (BCD) users. Furthermore, to assess differences between indications and changes in HRQoL over time.Study design:Prospective questionnaire survey.Setting:Tertiary referral center.Patients:Seventy-five patients with a percutaneous BCD.Main outcome measures:Glasgow Benefit Inventory (GBI) at 3 and 12 months postoperatively, Glasgow Health Status Inventory (GHSI) preoperatively, and 6 and 36 months postoperatively, device use at 6, 12, and 36 months. Changes over time were assessed and outcomes were compared between indications.Results:After implantation, 97% of all patients reported a positive benefit on the GBI total. The GHSI total had improved with median 15 points (Interquartile range [IQR] 12). At 36 months, median device use was 15 hours/day (IQR 10) and one nonuser was reported. Patients with bilateral hearing loss (BHL) showed greater improvement on the GHSI total (median 18 vs 14, p < 0.0001) and used their devices more frequently (median 16 vs 8 h/day, p < 0.0001) than patients with unilateral HL (UHL). Postoperative GHSI and GBI scores were consistent over time, in the entire patient population and for every indication. Between 6 and 36 months, device use was stable over time, except for patients with single-sided deafness (SSD; median −6.4 h/day, p = 0.009).Conclusion:The BCD improves HRQoL in patients with BHL, in patients with unilateral conductive/mixed hearing loss and in patients with SSD. Patients with BHL experienced a greater improvement in hearing status compared to patients with UHL. Although use decreased over time in SSD patients, device use was high for every indication.

Surgical Considerations for an Osseointegrated Steady State Implant (OSIA2®) in Children.

Surgical Considerations for an Osseointegrated Steady State Implant (OSIA2®) in Children.

Investigating Real-World Benefits of High-Frequency Gain in Bone-Anchored Users with Ecological Momentary Assessment and Real-Time Data Logging.

Purpose: To compare listening ability (speech reception thresholds) and real-life listening experience in users with a percutaneous bone conduction device (BCD) with two listening programs differing only in high-frequency gain. In situ real-life experiences were recorded with ecological momentary assessment (EMA) techniques combined with real-time acoustical data logging and standard retrospective questionnaires. Methods: Nineteen experienced BCD users participated in this study. They all used a Ponto 4 BCD from Oticon Medical during a 4-week trial period. Environmental data and device parameters (i.e., device usage and volume control) were logged in real-time on an iPhone via a custom iOS research app. At the end of the trial period, subjects filled in APHAB, SSQ, and preference questionnaires. Listening abilities with the two programs were evaluated with speech reception threshold tests. Results: The APHAB and SSQ questionnaires did not reveal any differences between the two listening programs. The EMAs revealed group-level effects, indicating that in speech and noisy listening environments, subjects preferred the default listening program, and found the program with additional high-frequency gain too loud. This finding was corroborated by the volume log—subjects avoided the higher volume control setting and reacted more to changes in environmental sound pressure levels when using the high-frequency gain program. Finally, day-to-day changes in EMAs revealed acclimatization effects in the listening experience for ratings of “sound quality” and “program suitability” of the BCD, but not for ratings of “loudness perception” and “speech understanding”. The acclimatization effect did not differ among the listening programs. Conclusion: Adding custom high-frequency amplification to the BCD target-gain prescription improves speech reception in laboratory tests under quiet conditions, but results in poorer real-life listening experiences due to loudness.

Sound localization with bilateral bone conduction devices

PurposeTo investigate sound localization in patients bilaterally fitted with bone conduction devices (BCDs). Additionally, clinically applicable methods to improve localization accuracy were explored.MethodsFifteen adults with bilaterally fitted percutaneous BCDs were included. At baseline, sound localization, (un)aided pure-tone thresholds, device use, speech, spatial and qualities of hearing scale (SSQ) and York hearing-related quality of life (YHRQL) questionnaire were measured. Settings to optimize sound localizing were added to the BCDs. At 1 month, sound localization was assessed again and localization was practiced with a series of sounds with visual feedback. At 3 months¸ localization performance, device use and questionnaire scores were determined again.ResultsAt baseline, one patient with congenital hearing loss demonstrated near excellent localization performance and four other patients (three with congenital hearing loss) localized sounds (quite) accurately. Seven patients with acquired hearing loss were able to lateralize sounds, i.e. identify whether sounds were coming from the left or right side, but could not localize sounds accurately. Three patients (one with congenital hearing loss) could not even lateralize sounds correctly. SSQ scores were significantly higher at 3 months. Localization performance, device use and YHRQL scores were not significantly different between visits.ConclusionIn this study, the majority of experienced bilateral BCD users could lateralize sounds and one third was able to localize sounds (quite) accurately. The localization performance was robust and stable over time. Although SSQ scores were increased at the last visit, optimizing device settings and a short practice session did not improve sound localization.

The Merits of Bilateral Application of Bone-Conduction Devices in Children With Bilateral Conductive Hearing Loss.

This study aims to characterize lateralization of sounds and localization of sounds in children with bilateral conductive hearing loss (BCHL) when listening with either one or two percutaneous bone conduction devices (BCDs). Sound lateralization was measured with the minimum audible angle test in which children were asked to indicate from which of the two visible speakers the sound originated. Sound localization was measured with a test in which stimuli were presented from speakers that were not visible to the children. In the sound localization test, 150 ms broadband noise bursts were presented, and sound level was roved over a 20-dB range. Because speakers were not visible the localization response was not affected by any visual cue. The sound localization test provides a clear distinction between lateralization and localization of sounds. Ten children with congenital BCHL and one child with acquired BCHL participated. Both lateralization and sound localization were better with bilateral BCDs compared with the unilaterally aided conditions. In the bilateral BCD condition, lateralization was close to normal in nearly all the children. The localization test demonstrated lateralization rather than sound localization behavior when listening with bilateral BCDs. Furthermore, in the unilateral aided condition, stimuli presented at different sound levels were mainly perceived at the same location. This study demonstrates that, in contrast to listening with two BCDs, children demonstrated difficulties in lateralization of sounds and in sound localization when listening with just one BCD (i.e., one BCD turned off). Because both lateralization and sound localization behavior were tested, it could be demonstrated that these children are more able to lateralize than localize sounds when listening with bilateral BCDs. The present study provides insight in (sub-optimal) sound localization capabilities of children with congenital BCHL in the unilateral-aided and bilateral-aided condition. Despite the sub-optimal results on sound localization, this study underlines the merits of bilateral application of BCDs in such children.

Contribution of spectral pinna cues for sound localization in children with congenital unilateral conductive hearing loss after hearing rehabilitation

Congenital unilateral conductive hearing loss (UCHL) jeopardizes directional hearing and speech perception in noisy conditions. Potentially, children with congenital UCHL can benefit from fitting a hearing device, such as a bone-conduction device (BCD). However, the literature reports limited benefit from fitting a BCD, and often, surprisingly, relatively good sound localization in the unaided condition is reported. In this study, we hypothesized that the limited benefit with a BCD is related to (i) insufficient access to binaural cues and (ii) relying on monaural spectral pinna cues for sound localization in the horizontal plane. Directional hearing was tested in seventeen children with congenital UCHL (age 6–19) using a percutaneous BCD. Additionally, a mold was placed in the pinna of the normal-hearing ear to diminish direction-dependent spectral pinna cues. Relatively good localization in azimuth was found in the unaided hearing condition in the majority of the children. Sound localization improved when listening with a BCD, and no correlation between age of implantation and aided localization performance was found. When the mold was inserted, the unaided and aided localization abilities of most children deteriorated. Interestingly, in the children with poor localization performance in the unaided condition, sound localization improved significantly with the BCD, and was hardly affected by molding the pinna of the normal-hearing ear. These observations indicate that the majority of these children rely on spectral pinna cues to localize sounds, independent of listening with or without their device. In conclusion, an important reason for the limited benefit of BCD fitting in children with congenital UCHL might be ascribed to an effective coping strategy (use of spectral pinna cues) that still plays a dominant role after BCD fitting.

Management of Traumatic Injury and Osseointegration Failure in Children With Percutaneous Bone Conduction Implants.

This study examines the incidence and management of traumatic loss or osseointegration failure of percutaneous bone conduction implants in children. Case series. Pediatric tertiary care institution. Children who underwent percutaneous osseointegrated implant placement from 1996 to 2016. Clinical evaluation and revision surgery after implant loss. This study compares the characteristics of children who experienced traumatic loss of implant to those who did not to calculate odds ratios (ORs) describing the risk of injury and investigate device utilization after implant failure. One hundred forty-seven children received percutaneous bone conduction devices; 129 were followed for at least 1 year. Trauma occurred in 19 of 129 cases (15%). Among children with traumatic injury, mean age at initial surgery was 5 years (SD = ±3.3), and 42% had a developmental delay. Among children without traumatic injury, mean age at initial surgery was 6.5 years (SD = ±4.4), and 28% had a developmental delay. Multivariate logistic regression found no significant differences in age, sex, or developmental delay associated with implant loss. In five of 19 traumatic cases (26%), the implant remained in situ due to either skull fracture or abutment loss. In the remaining 14 of 19 cases (74%), there was osseointegration failure with extrusion of the implant. Seventeen children underwent revision surgery utilizing previously placed "sleeper," or backup, osseointegrated implant, and 14 (82%) of these continued to use their device. Two patients with extruded implants did not undergo revision surgery. Traumatic injury or osseointegration failure leads to loss of percutaneous bone conduction implants in approximately 15% of children. Revision surgery is often successful.

Effect of transducer attachment on vibration transmission and transcranial attenuation for direct drive bone conduction stimulation

Direct drive bone conduction devices (BCDs) are used to rehabilitate patients with conductive or mixed hearing loss by stimulating the skull bone directly, either with an implanted transducer (active transcutaneous BCDs), or through a skin penetrating abutment rigidly coupled to an external vibrating transducer (percutaneous BCDs). Active transcutaneous BCDs have been under development to overcome limitations of the percutaneous bone anchored hearing aid (BAHA), mainly related to the skin penetration. The attachment of a direct drive BCD to the skull bone can differ significantly between devices, and possibly influence the vibrations’ transmission to the cochleae.In this study, four different attachments are considered: (A) small-sized flat surface, (B) extended flat surface, (C) bar with a screw at both ends, and (D) standard bone anchored hearing aid screw. A, B, and C represent three active transcutaneous options, while D is for percutaneous applications. The primary aim of this study was to investigate how the different transcutaneous attachments (A, B, and C) affect the transmission of vibrations to the cochleae to the ipsilateral and the contralateral side. A secondary aim was to evaluate and compare transcranial attenuation (TA, ipsilateral minus contralateral signal level) between transcutaneous (A, B, and C) and percutaneous attachments (D).Measurements were performed on four human heads, measuring cochlear promontory velocity with a LDV (laser Doppler vibrometer) and sound pressure in the ear canal (ECSP) with an inserted microphone. The stimulation signal was a swept sine between 0.1 and 10 kHz. The comparison of ipsilateral transmission between transcutaneous adaptors A, B, and C was in agreement with previous findings, confirming that: (1) Adaptor C seems to give the most effective transmission for frequencies around 6 kHz but somewhat lower in the mid frequency range, and (2) keeping a smaller contact area seems to provide advantages compared to a more extended one. The same trends were seen ipsilaterally and contralaterally. The observed TA was similar for adaptors A, B, and C at the mastoid position, ranging -10-0 dB below 500 Hz, and 10–20 dB above. A lower TA was seen above 500 Hz when using adaptor D at the parietal position.

Determining fitting ranges of various bone conduction hearing aids.

To define fitting ranges for nine bone conduction devices (BCDs) over different frequencies based on the device's maximum power output (MPO) and to validate the assessment of MPO of BCDs in the ear canal. Maximum power output (MPO) is an important characteristic when fitting BCDs. It is the highest output level a device can deliver and is one of the major determinants of a device's fitting range. A skull simulator can be used to verify MPO of percutaneous BCDs. No such simulator is available for active and passive transcutaneous devices. The MPO of nine different BCDs was assessed either by real-ear measurements and/or with skull simulator measurements. MPO and cross-validation of the methods using the Bland-Altman method. Percutaneous BCDs have higher MPO levels compared to active and passive transcutaneous devices. This results in a wide dynamic range of hearing for percutaneous devices. Moreover, the assessment of MPO by real-ear measurements was validated. Based on MPO data, fitting ranges were defined for nine BCDs over seven frequencies.

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

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

A Systematic Review on Complications of Tissue Preservation Surgical Techniques in Percutaneous Bone Conduction Hearing Devices.

To investigate skin-related postoperative complications from tissue preservation approaches in percutaneous bone conduction device (BCD) implantations. PubMed, Embase, and Cochrane Library. We identified studies on BCDs including the opted surgical technique and derived complications. Retrieved articles were screened using predefined inclusion criteria. Critical appraisal included directness of evidence and risk of bias. Studies that successfully passed critical appraisal were included. Outcome measures included patient demographics, surgery time, follow-up time, and complications reported by Holgers classification. We selected 18 articles for data extraction; encompassing 381 BCDs implanted using non-skin thinning approaches. Four studies reported an implantation technique using the punch method (81 implants), 13 studies applied the linear incision technique without soft tissue reduction (288 implants) and one study used the Weber technique (12 implants). Holgers 3 was described in 2.5% following the punch technique, in 5.9% following the linear incision technique, and in no implants following the Weber technique. One patient was mentioned having Holgers 4, skin overgrowth was reported in 6 patients, and 10 studies compared their non-skin thinning technique with a skin-thinning technique. Overall, the soft tissue preservation technique had a similar or superior complication rate, shorter surgical time, and better and faster healing, compared with the soft tissue reduction technique. Tissue preservation surgical techniques for percutaneous BCDs have limited postoperative skin complication rates. Moreover, these techniques are suggested to have at least similar complications rates compared with skin-thinning techniques.

Three-year experience with the Sophono in children with congenital conductive unilateral hearing loss: tolerability, audiometry, and sound localization compared to a bone-anchored hearing aid.

Bone conduction devices (BCDs) are advocated as an amplification option for patients with congenital conductive unilateral hearing loss (UHL), while other treatment options could also be considered. The current study compared a transcutaneous BCD (Sophono) with a percutaneous BCD (bone-anchored hearing aid, BAHA) in 12 children with congenital conductive UHL. Tolerability, audiometry, and sound localization abilities with both types of BCD were studied retrospectively. The mean follow-up was 3.6 years for the Sophono users (n = 6) and 4.7 years for the BAHA users (n = 6). In each group, two patients had stopped using their BCD. Tolerability was favorable for the Sophono. Aided thresholds with the Sophono were unsatisfactory, as they did not reach under a mean pure tone average of 30 dB HL. Sound localization generally improved with both the Sophono and the BAHA, although localization abilities did not reach the level of normal hearing children. These findings, together with previously reported outcomes, are important to take into account when counseling patients and their caretakers. The selection of a suitable amplification option should always be made deliberately and on individual basis for each patient in this diverse group of children with congenital conductive UHL.

Three year experience with the cochlear BAHA attract implant: a systematic review of the literature.

BackgroundBone conduction devices are widely used and indicated in cases of conductive, mixed or single sided deafness where conventional hearing aids are not indicated or tolerated. Percutaneous bone-conduction devices gave satisfactory hearing outcomes but were frequently complicated by soft tissue reactions. Transcutaneous bone conduction devices were developed in order to address some of the issues related to the skin-penetrating abutment. The aim of this article is to present a systematic review of the indications, surgical technique and audiological, clinical and functional outcomes of the BAHA Attract device reported so far.MethodsA systematic computer-based literature search was performed on the PubMed database as well as Scopus, Cochrane and Google Scholar. Out of 497 articles, 10 studies and 89 reported cases were finally included in our review.ResultsThe vast majority of implanted patients were satisfied with the aesthetics of the device scoring highly at the Abbreviated Profile of Hearing Aid Benefit, Glasgow Benefit Inventory and Client Oriented Scale of Improvement. Overall, hearing outcomes, tested by various means including speech in noise, free field hearing testing and word discrimination scores showed a significant improvement. Complications included seroma or haematoma formation, numbness around the area of the flap, swelling and detachment of the sound processor from the external magnet.ConclusionsThe functional and audiological results presented so far in the literature have been satisfactory and the complication rate is low compared to the skin penetrating Bone Conduction Devices. Further robust trials will be needed to study the long-term outcomes and any adverse effects.

Long-term Compliance and Satisfaction With Percutaneous Bone Conduction Devices in Patients With Congenital Unilateral Conductive Hearing Loss.

Patients with congenital unilateral conductive hearing loss (UCHL) can either be watchful monitored or treated surgically through the fitting of a percutaneous bone conduction device (BCD) or, in some cases, atresia repair. The current study evaluated the long-term compliance and satisfaction with a percutaneous BCD in this specific population. Fifty-three consecutive patients with congenital UCHL treated with a percutaneous BCD in our tertiary referral center between 1998 and 2011 were identified. Clinical and audiological data were retrospectively gathered from the patients' files. The patients were interviewed by telephone about their current device usage status and were asked to complete the Speech, Spatial and Qualities of Hearing Scale (SSQ). Compliance with the BCD was 56.6% after a mean follow-up of 7 years. The mean age at implantation of the users (22 years) was significantly higher than that of the nonusers (10 years). The mean time of device usage before the patients stopped using the BCD was 5 years. The primary reasons mentioned for quitting the BCD were experiencing excess background noise and/or subjectively not receiving enough benefit. Objectively measured features of binaural processing affected by the BCD were found to correlate with long-term BCD usage. The SSQ revealed significant improvement in the aided condition compared with the nonaided condition in the users, in contrast to the nonusers. The current disappointing long-term compliance figures indicate the need for an even more careful and individualized approach with life-long follow-up when fitting BCDs in this specific population, especially in children.