Bone Conduction Implants Research Articles

The First Active Transcutaneous Bone Conduction Implant in Romania-Case Report of Permanent Conductive Hearing Loss Due to Cleft Palate

The First Active Transcutaneous Bone Conduction Implant in Romania-Case Report of Permanent Conductive Hearing Loss Due to Cleft Palate

Transcutaneous Baha Attract system: Long‐term outcomes of the French multicenter study

Bone conduction implants based on abutment-driven acoustic transmission result in good hearing outcomes; however, skin complications impact the quality of life (QOL) and possibly the viability of the device for many patients. The transcutaneous magnetic Baha® Attract technology was developed with the goal of minimising skin complications. To analyse surgical, auditory and QOL outcomes for patients implanted with the Baha® Attract. Prospective multicentre cohort study. Four French tertiary referral centres. Thirty-two patients implanted with the Baha® Attract, including 25 with conductive and mixed hearing loss and 7 with single-sided deafness. Postoperative follow-up involved the visual analysis of soft tissue adaptation and sound processor magnet strength measurement. The audiometric outcomes were evaluated in quiet and noise, and the QOL was assessed using three different questionnaires. After 12months of use, soft tissue was thinner, and mean magnet strength was significantly decreased (3.7-3.1, P<0.05) relative to measures during surgery. The speech recognition threshold in quiet significantly improved compared to unaided situation (73-44 dB HL respectively, P<0.001) as did functional gain in noise (+2.8). All QOL scores improved, and the APHAB questionnaire score correlated with the audiometric outcomes. The Baha® Attract technology results in significant hearing gain and improves QOL. Skin complications were not observed, although surgeons, audiologists and patients should be aware of soft tissue evolution during the first postoperative year. The reversibility of this implant is a major advantage that allows switching to another system if hearing degrades.

Retrospective Analysis of Hearing-Impaired Adult Patients Treated With an Active Transcutaneous Bone Conduction Implant.

To determine the therapeutic success and safety of an active transcutaneous bone conduction implant (tBCI) in adult patients with conductive or mixed hearing loss. Retrospective case review. Five university hospitals in Frankfurt, Hannover, Dresden, Würzburg, and Vienna. Data were analyzed from 61 patients (31 women, 30 men) with a mean age of 50 years (min. 26, max. 80). Forty patients had mixed, and 21 conductive hearing loss. Typical etiologies were history of otitis media (n = 20) and cholesteatoma (n = 17). Implantation of the active tBCI. Data were analyzed for the following time points: up to 6 months postoperatively ("short-term"), 6 to 37 months postoperatively ("long-term"), and the last available measurement per patient ("most recent"). Pure-tone audiometry (air and bone conduction, AC and BC) and sound field thresholds with warble tones (WT), word recognition scores with Freiburger monosyllables (WRS), as well as speech reception thresholds (SRT) using the Oldenburg sentence test (OLSA) in quiet (SRT) and in noise (signal-to-noise ratio, SNR) were collected. No significant changes in air- and bone-conduction thresholds were observed after implantation. A mean WRS improvement of 54% using the active tBCI was shown at the short-term assessment, i.e., a mean score of 79% compared with 25% in the unaided condition. Results remained stable, with a mean score of 75% at the long-term assessment. SRT in noise improved by 3.6 dB SNR in the implanted ear at the short-term assessment. Overall six adverse events and four serious adverse events were reported, resulting in a rate of 9.84 and 6.56%, respectively. The tBCI clearly improves speech intelligibility in patients with conductive or mixed hearing loss, showing stable results up to 1 year post-implantation.

The current status and applications of implantable bone-conduction devices

Implantable bone-conduction devices are characterized by the fact that the vibration is transmitted through bone conduction. The technology and surgical techniques in the application of implantable bone-conduction devices have developed considerably in recent years, experiencing a transformation from percutaneous to transcutaneous implantation. This article reviewed current developments in the types, surgical indications, and complications, as well as compared between the various bone-conduction devices to provid references for clinical application.

Transcutaneous bone conductive implants in patients with conductive/mixed hearing loss: audiological outcomes in noise condition

Background: Recently, the use of transcutaneous bone conduction implants (BCIs) has been increased. However, scarce data about BCI hearing recovery in noise conditions have been reported.Objectives: To investigate the audiological benefits obtained with transcutaneous BCI-Sophono Alpha System in noise conditions. To evaluate post-implantation clinical outcomes and patient satisfaction levels.Materials and methods: Fourteen patients suffering from conductive or mixed hearing loss implanted with the Sophono Alpha System were evaluated. Patients underwent physical examination, free-field pure-tone and speech audiometry both in unaided and aided conditions. The matrix sentence test was employed with fixed noise at 65 dB, and with a fluctuating primary signal, in three different conditions of noise presentations (S0/N0, S0/Ncontra, S0/Nipsi).Results: Hearing gain, expressed as the difference between pre-implant AC and post-implant SAS free field, was on average 26.7 dB. The unaided speech recognition score in quiet conditions had a mean value of 64.6%, and improved after SAS implantation, achieving mean values of 98.2%. SRT50 with the matrix sentence test improved in all three conditions of noise presentation.Conclusions: Sophono Alpha System devices represent a valid treatment option for hearing rehabilitation of patients with conductive or mixed hearing loss. The audiological results regarding hearing gain in noise conditions were good.

Active Transcutaneous Bone Conduction Implant: Middle Fossa Placement Technique in Children With Bilateral Microtia and External Auditory Canal Atresia.

The aim of this study is to present the middle fossa technique (MFT) as an alternative for patients who cannot undergo traditional surgery for active transcutaneous bone conduction implants (ATBCI) due to their altered anatomy or desire for future aesthetic reconstruction. A case series descriptive study was designed. The MFT was developed. Preoperative and postoperative information from 24 patients with external auditory canal atresia (EACA) and implanted with ATBCI was reviewed. A total of 24 children with bilateral EACA received implants in the middle cranial fossa. Their average age was 12. Of these patients, eight had an associated congenital disorder: Goldenhar Syndrome, Treacher Collins Syndrome or the Pierre Robin Sequence. The average follow-up was at 17 months (ranging from between 2- and 36 mo) and there were no major complications. Four patients showed skin erythema at the processor site after turn on, which was solved by lowering the magnet strength. One patient had a scalp hematoma that required puncture drainage. The hearing thresholds went down on average from 66.5 to 25.2 dB 1 month after turn on. Speech recognition improved respectively from 29.4% without and 78.9% with a bone conduction hearing aid to 96.4%. MFT placement of the ATBCI was proven to be safe and effective and a viable option for treating pediatric patients with EACA who cannot receive implants at the sinodural angle or in the retrosigmoidal position because of their altered anatomy and/or desire for future aesthetic reconstruction.

Resultados auditivos del sistema activo de conducción ósea Bonebridge® en hipoacusias conductivas o mixtas

ObjectiveThe active transcutaneous bone conduction implant Bonebridge®, is indicated for patients affected by bilateral conductive/mixed hearing loss or unilateral sensorineural hearing loss, showing hearing outcomes similar to other percutaneous bone conduction implants, but with a lower rate of complications. The aim of this study was to analyze the hearing outcomes in a series of 26 patients affected by conductive or mixed hearing loss and treated with Bonebridge®. Methods26 of 30 patients implanted with Bonebridge® between October 2012 and May 2017, were included in the study. We compared the air conduction thresholds at the frequencies 500, 1000, 2000, 3000, 4000Hz, the SRT50% and the percentage of correct answers at an intensity of 50dB with and without the implant. Results“Pure tone average” with the implant was 34.91dB showing an average gain of 33.46dB. Average SRT 50% with the implant was 34.33dB, whereas before the surgery no patient achieved 50% of correct answers at a sound intensity of 50dB. The percentage of correct answers at 50dB changed from 11% without the implant to 85% with it. We only observed one complication consisting of an extrusion of the implant in a patient with a history of 2 previous rhytidectomies. ConclusionsThe hearing outcomes obtained in our study are similar to those published in the literature. Bonebridge® represents an excellent alternative in the treatment of conductive or mixed hearing loss, and with a lower rate of complications.

Horizontal sound localisation accuracy in individuals with conductive hearing loss: effect of the bone conduction implant

Objective: The objective of this study is to quantify the effect of the Bone Conduction Implant (BCI) on sound localisation accuracy in subjects with conductive hearing loss (CHL).Design: The subjects were tested in a horizontal sound localisation task in which localisation responses were objectively obtained by eye-tracking, in a prospective, cross-sectional design. The tests were performed unaided and unilaterally aided. The stimulus used had a spectrum similar to female speech and was presented at 63 and 73 dB SPL. The main outcome measure was the error index (EI), ranging from 0 to 1 (perfect to random performance).Study sample: Eleven subjects (aged 21–75 years, five females) with BCI participated in the study. Their mixed/conductive hearing loss was either unilateral (n = 5) or bilateral (n = 6).Results: Three of five subjects (60%) with unilateral CHL, and four of six subjects (67%) with bilateral CHL showed significantly improved sound localisation when using a unilateral BCI (p < .05). For the subjects with bilateral CHL, a distinct linear relation between aided sound localisation and hearing thresholds in the non-implant ear existed at 73 dB SPL (18% decrease in the EI per 10 dB decrease in pure-tone average, r = 0.98, p < .001).Conclusions: Individuals with mixed/conductive hearing loss may benefit from a unilateral BCI in sound localisation.

A functional and anatomical comparison between two passive transcutaneous bone conduction implants in children

ObjectiveTo compare anatomical and functional outcomes of two passive transcutaneous bone conduction implant systems: Sophono™ and BAHA Attract™. Materials and methodsTwenty patients, affected by bilateral conductive hearing loss, underwent unilateral transcutaneous bone conduction implant surgery. Ten children received a Sophono™ implant (6 males, 4 females, mean age 11 years, mean unaided Pure Tone Average (PTA) 0.25-4kHz = 69.70dB HL) and 10 a BAHA Attract™ system (7 males, 3 females, mean age 19 years, mean unaided PTA0.25-4kHz = 66.40dB HL). The following outcomes were considered: incidence of local complications, hearing aid benefit, hearing aid gain and changes in quality of life (QOL), as measured by the Glasgow Children's Benefit Inventory (GCBI). ResultsOne patient in the Sophono group experienced magnet-related skin decubitus, while two patients (one per group) had skin hyperemia in the area overlying the magnet. The mean BAHA-aided threshold was 23.70dB, whereas the mean Sophono-aided threshold was 31.60dB. The mean gain was significantly different for lower frequencies, the BAHA having better functional outcomes. All patients reported an improvement in their QOL. ConclusionGiven the lower thickness of the internal magnet, the Sophono™ system might be more suitable for younger children, whereas BAHA offered better functional results. Both systems can be considered valid and safe options for the functional rehabilitation of conductive hearing loss in children, provided that precautions are observed, such as a gradual use of the device and use of the least powerful magnets in the first months after the activation.

Transmastoid implantability of an active transcutaneous bone conduction implant in adults with regard to the underlying pathology: a radiological simulation study

Objectives: To compare the feasibility of transmastoid implantation of an active transcutaneous bone conduction device (BCD) in the most important pathologies of the temporal bone and the impact of implant lifts in adulthood.Methods: First, clinical predominant pathologies for implantation of this BCD were evaluated by a literature review. Then, high-resolution CT of 240 temporal bones with neuro-otologic diseases (NOD), chronic otitis media (COM), or cholesteatoma, respectively, were investigated regarding their implantability, using a radiological simulation program.Results: Chronic inflammatory diseases (CID) of the temporal bone with or without cholesteatoma account for most adults scheduled for an active BCD. Complete implantation was possible in almost all cases with NOD as well as COM, requiring an implant lift in 50% of COM and 20% of NOD (p = .025) cases. In contrast, in subjects with cholesteatoma, implantation required an additional tool in 92% of cases, leading to 59% implantability rate in these temporal bones.Conclusion: Adult subjects with CID of the temporal bone show more limiting anatomical conditions for transmastoid placement of an active transcutaneous BCD than those with single-sided deafness. Implant lifts increase the implantability significantly in subjects with COM and particularly in those with cholesteatoma.

Current Developments and Challenge of Implantable Bone Conduction Hearing Aids

Current Developments and Challenge of Implantable Bone Conduction Hearing Aids

Hearing Rehabilitation in Congenital Middle Ear Malformation.

Microtia and atresia cause significant conductive hearing loss of up to 60 dB HL. The bilateral cases suffer from severely restricted communication abilities and require immediate acoustic stimulation. There is also growing evidence that unilateral cases benefit from an early and selective stimulation of the affected side. Hearing restoration can be performed in selected cases of minor malformation by classic middle ear reconstruction. However, the majority of patients presumably benefit better from a hearing aid. There are 3 main types: active middle ear implants, active bone conduction implants and passive bone conduction implants. All implants improve speech perception, speech recognition, the signal-to-noise ratio and directional hearing. The extent varies among implants and requires further studies. Decision making on the implant type depends on the extent of malformation and hence the preoperative imaging. New scoring systems provide reliable risk stratification. Second it depends on the age of the patient. The active middle ear implants provide a selective stimulation of the affected side and are beneficial if implanted in the first years of life during the maturation period of the auditory system. In conclusion, hearing rehabilitation of congenital atresia should be performed as early as possible. This includes not only the bilateral but also the unilateral affected patients.

Utility of 3D printed temporal bones in pre-surgical planning for complex BoneBridge cases.

With the advent of single-sided hearing loss increasingly being treated with cochlear implantation, bone conduction implants are reserved for cases of conductive and mixed hearing loss with greater complexity. The BoneBridge (BB, MED-EL, Innsbruck, Austria) is an active fully implantable device with no attenuation of sound energy through soft tissue. However, the floating mass transducer (FMT) part of the device is very bulky, which limits insertion in complicated ears. In this study, 3D printed temporal bones of patients were used to study its utility in preoperative planning on complicated cases. Computed tomography (CT) scans of 16 ears were used to 3D print their temporal bones. Three otologists graded the use of routine preoperative planning provided by MED-EL and that of operating on the 3D printed bone of the patient. Data were collated to assess the advantage and disadvantage of the technology. There was a statistically significant benefit in using 3D printed temporal bones to plan surgery for difficult cases of BoneBridge surgery compared to the current standard. Surgeons preferred to have the printed bones in theatre to plan their drill sites and make the transition of the planning to the patient's operation more precise. 3D printing is an innovative use of technology in the use of preoperative planning for complex ear surgery. Surgical planning can be done on the patient's own anatomy which may help to decrease operating time, reduce cost, increase surgical precision and thus reduce complications.

Sound Localization in Patients With Congenital Unilateral Conductive Hearing Loss With a Transcutaneous Bone Conduction Implant.

There is no consensus regarding the benefit of implantable hearing aids in congenital unilateral conductive hearing loss (UCHL). This study aimed to measure sound source localization performance in patients with congenital UCHL and contralateral normal hearing who received a new bone conduction implant. Evaluation of within-subject performance differences for sound source localization in a horizontal plane. Tertiary referral center. Five patients with atresia of the external auditory canal and contralateral normal hearing implanted with transcutaneous bone conduction implant at the Medical University of Vienna were tested. Activated/deactivated implant. Sound source localization test; localization performance quantified using the root mean square (RMS) error. Sound source localization ability was highly variable among individual subjects, with RMS errors ranging from 21 to 40 degrees. Horizontal plane localization performance in aided conditions showed statistically significant improvement compared with the unaided conditions, with RMS errors ranging from 17 to 27 degrees. The mean RMS error decreased by a factor of 0.71 (p < 0.001). Analysis revealed improved sound localization performance in a horizontal plane with the activated transcutaneous bone conduction implant. Some patients with congenital UCHL might be capable of developing improved horizontal plane localization abilities with the binaural cues provided by this device.

Direct cost comparison of minimally invasive punch technique versus traditional approaches for percutaneous bone anchored hearing devices

BackgroundMinimally Invasive Ponto Surgery (MIPS) was recently described as a new technique to facilitate the placement of percutaneous bone anchored hearing devices.The procedure has resulted in a simplification of the surgical steps and a dramatic reduction in surgical time while maintaining excellent patient outcomes. Given these developments, our group sought to move the procedure from the main operating suite where they have traditionally been performed. This study aims to test the null hypothesis that MIPS and open approaches have the same direct costs for the implantation of percutaneous bone anchored hearing devices in a Canadian public hospital setting.MethodsA retrospective direct cost comparison of MIPS and open approaches for the implantation of bone conduction implants was conducted. Indirect and future costs were not included in the fiscal analysis.A simple cost comparison of the two approaches was made considering time, staff and equipment needs. All 12 operations were performed on adult patients from 2013 to 2016 by the same surgeon at a single hospital site.ResultsMIPS has a total mean reduction in cost of CAD$456.83 per operation from the hospital perspective when compared to open approaches. The average duration of the MIPS operation was 7 min, which is on average 61 min shorter compared with open approaches.ConclusionThe MIPS technique was more cost effective than traditional open approaches. This primarily reflects a direct consequence of a reduction in surgical time, with further contributions from reduced staffing and equipment costs. This simple, quick intervention proved to be feasible when performed outside the main operating room. A blister pack of required equipment could prove convenient and further reduce costs.

Measurement and Analysis of Feedback and Nonlinearities for the Codacs Direct Acoustic Cochlear Implant

Acoustic feedback is a very common problem in hearing instruments. Not only does it occur in common behind-the-ear or in-the-ear hearing aids, it also affects bone conduction implants, middle ear implants, and more recent devices, such as the direct acoustic cochlear implant (DACI). In this paper, we present the data and analysis relating to the feedback path characterization of the Cochlear™ Codacs™ DACI, performed on fresh frozen cadaver heads in four different measurement sessions. The general objectives were the following: 1) To measure and analyze the feedback path of the system and check for possible specimen-dependent variabilities; 2) To assess whether this feedback path is affected by an incorrect implantation; 3) To check for nonlinear behavior; and 4) To determine differences between tissular and airborne feedback. The data analysis reveals that the feedback seems to be dependent on the specific head morphology of the implanted specimen, and that an incorrect implantation might strongly affect the feedback path; additionally, the analysis reveals that some nonlinear behavior at high stimulus levels can be expected and, finally, that the feedback path is characterized by a tissular feedback component with a rather different frequency content compared to the airborne feedback component.

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.

Adverse skin reactions following percutaneous bone conduction implant surgery using the linear incision technique with and without subcutaneous tissue reduction

Conclusions: Adverse skin reactions were equally distributed among age groups, surgical technique, or presence of a retroauricular incision. Implant loss was observed more frequently in children when compared to adults and elderly.Objective: A bone conduction (osseointegrated) implant can be used for rehabilitation of patients with conductive hearing loss or single-sided deafness. The surgical technique has been modified to minimize adverse skin reactions and other complications. Two commonly used techniques are the linear incision technique with subcutaneous tissue reduction and the technique without tissue reduction. The primary aim is to compare the complication rate between the two surgical techniques.Methods: Retrospective study on all bone conduction implant cases implanted between April 1990 and July 2014 at a tertiary referral center. Skin reactions were graded by Holgers’ scale (grade 0–1: ‘normal’, grade 2–3: ‘adverse’). The worst follow-up available was reported.Results: Of the 289 bone conduction implants, 25 were implanted in children, 220 in adults, and 44 in elderly. Implant loss occurred in 2.8% of all cases: 8.0% in children, 2.3% in adults, and 2.3% in the elderly. Skin overgrowth was seen in 4.2%: 4% in children, 4.8% in adults, and 3.5% in the elderly. No differences were observed in the amount of adverse skin reactions (16.8% vs 14.7%) or skin overgrowth (4.6% vs 2.9%) between the surgical techniques. There was no difference in adverse skin reactions if the patient had a retroauricular incision (14.4% with vs 17.8% without prior incision).

PMD66 - HEARING RESTORATION, QUALITY OF LIFE, AND SAFETY OUTCOMES IN BONE-CONDUCTION DEVICES FOR PATIENTS WITH CONDUCTIVE OR MIXED HEARING LOSS OR SINGLE-SIDE DEAFNESS

To provide a comprehensive literature review on the various bone-conduction devices (BCDs) available, including bone-anchored hearing aids (BAHAs). A comprehensive search strategy was defined to perform a literature review of the data available to date on the different types of marketed BCDs for hearing rehabilitation in patients presenting with conductive hearing loss (CHL), mixed hearing loss (MHL), or single-side deafness (SSD). A search was conducted on December 22nd, 2015 on the PubMed, EMBASE and Google Scholar databases. Search criteria included patients presenting with CHL, MHL or SSD, and implanted with percutaneous (pBCI) or transcutaneous (tBCI) bone conduction implants. Non-systematic reviews, case reports and clinical studies on <5 patients were excluded. The literature analysis specifically examined the type of implantation (pBCI vs. tBCI), the principle of operation (active device, i.e. direct drive to the skull bone vs. passive device, i.e. skin drive), or by indication. 1,223 potentially relevant publications were identified; on full review, 95 studies met eligibility criteria. Hearing restoration, QoL and patient-reported outcomes measures have been increasingly documented for each technology in recent years. While the tBCIs seemed to be associated with a lower rate of skin complications than pBCIs, all the other parameters (clinical outcomes and QoL) seemed to be similarly distributed across all devices. The available data are still insufficient and the measurements’ sensitivities do not allow for a robust comparison between the different types of implants. The evidence base to support any differentiation between ‘passive’ and ‘active’ implants is insufficient, and direct comparison data is scarce. Future clinical studies and case reports should continue to investigate the clinical efficacy and safety outcomes related to the use of these devices, so as to provide physicians a more refined patient selection rationale and evidence-based practice pathways according to each device’s characteristics.

Bone Conduction Implant, clinical trial of a new transcutaneous implant and results so far

Bone Conduction Implant, clinical trial of a new transcutaneous implant and results so far