Bone Conduction Hearing Implants Research Articles

Acute Otologic Infections in Pediatric Patients

AbstractThis article summarizes significant acute infections involving the pediatric temporal bone. First, the management of acute otitis media (AOM) is discussed, including the medical and surgical management of invasive intracranial and extracranial complications associated with advanced disease. The clinical and radiographic findings, microbiology, and management of acute mastoiditis are discussed in greater detail, followed by the presentation and treatment of acute otitis externa (AOE). Finally, we discuss infectious considerations in auditory implants. The indications and use of both cochlear implants (CI) and bone conduction hearing implants have rapidly expanded in children, requiring greater understanding of managing infections in the context of these devices.

Positioning a Novel Transcutaneous Bone Conduction Hearing Implant: a Systematic Anatomical and Radiological Study to Standardize the Retrosigmoid Approach, Correlating Navigation-guided, and Landmark-based Surgery

Anatomical and radiological evaluation improves safety and accuracy of the retrosigmoid approach for positioning a transcutaneous bone conduction implant and provides anatomical reference data for standardized, landmark-based implantation at this alternative site. The primary implantation site for the floating mass transducer of a novel bone conduction hearing implant is the mastoid. However, anatomical limitations or previous mastoid surgery may prevent mastoid implantation. Therefore, the retrosigmoid approach has been introduced as an alternative. Mastoid and retrosigmoid implantation sites were radiologically identified and evaluated in preoperative computed tomography scans of anatomical head specimens. Navigation-guided implantation was then performed in the retrosigmoid site (n = 20). The optimal retrosigmoid position was determined in relation to both the asterion and the mastoid notch as surgical landmarks in an anatomical coordinate system. Preoperative radiological analysis revealed spatial limitations in the mastoid in 45% of the specimens. Navigation-guided retrosigmoid implantation was possible without affecting the sigmoid sinus in all the specimens. The optimal implantation site was located 1.9 ± 0.1 cm posterior/1.7 ± 0.1 cm inferior to the asterion and 3.3 ± 0.2 cm posterior/2.1 ± 0.1 cm superior to the mastoid notch.Retrosigmoid skull thickness was 6.6 ± 0.4 mm, measured anatomically, 7.0 ± 0.4 mm, measured radiologically and 6.7 ± 0.5 mm, measured with the navigation software. The navigation-guided retrosigmoid approach seemed to be a reliable procedure in all the specimens. Measurements of bone thickness revealed the need for spacers in 95% of the specimens. Reference coordinates of the optimal implantation site are provided and can confirm image-guided surgery or facilitate orientation if a navigation system is not available.

Update on Bone-Conduction Auditory Brainstem Responses: A Review.

Auditory brainstem responses (ABR) have been used as a powerful and the most common objective tool to evaluate hearing sensitivity and to diagnose the types of hearing loss and neurological disorders, through the auditory peripheral pathway to a central level of the brainstem, since 1971. Although bone-conduction (BC) ABR could be an alternative to air-conduction (AC) ABR, as the former overcomes some limitations of the latter, the majority of clinicians rarely utilize it due to a lack of knowledge and no routine test administration. This review presents the weaknesses of AC ABR that apply to all clinical population, and discusses the development of BC ABR. The optimal placements of bone oscillators to obtain favorable clinical outcomes in infants, children, and adults, and the appropriate stimuli for BC ABR are examined. While providing absolute thresholds and latencies of BC ABR based on previous studies compared to AC ABR, this review includes clinical data of infants and young children with both normal hearing in terms of maturation, and with pathology such as congenital external auditory canal atresia. We recommend the future clinical application of BC ABR for candidacy as well as for patients with BC hearing implants.

Current Developments and Challenge of Implantable Bone Conduction Hearing Aids

Current Developments and Challenge of Implantable Bone Conduction Hearing Aids

Advances in the Field of Bone Conduction Hearing Implants.

The number of marketed bone-conduction hearing implants (BCHIs) has been steadily growing, with multiple percutaneous devices and transcutaneous devices now available. However, studies assessing efficacy often have small sample sizes and employ different assessment methodologies. Thus, there is a paucity of evidence to guide clinicians to the most appropriate device for each patient. This paper outlines audiological guidelines for the latest devices, as well as research from the most up-to-date clinical trials. We also outline the evidence base for some potentially contentious issues in the field of bone conduction, including bilateral fitting of BCHIs in those with bilateral conductive hearing loss as well as the use of BCHIs in single-sided deafness (SSD). Bilateral fitting of BCHIs have been found to significantly increase the hearing thresholds in quiet and improve sound localization, but to give limited benefits in background noise. Studies conducted via multiple assessment questionnaires have found strong evidence of subjective benefits for the use of BCHIs in SSD. However, there is little objective evidence of benefit for SSD patients from sound localization and speech in noise tests.

Passive Transcutaneous Bone Conduction Hearing Implants: A Systematic Review.

To systematically review the literature on currently available passive transcutaneous bone conduction hearing implants (pTCBI) with regard to complications, audiological outcomes, and quality-of-life scores. MEDLINE, EMBASE, Scopus, and Cochrane Library. All identified English-language articles reporting on the implantation of currently available pTCBI's and their complications. Both pediatric and adult patients were included. No limitation was placed on study design or level of evidence. Complications, audiological outcomes including mean pure-tone average gain and mean speech reception threshold gain, and quality-of-life outcomes. Twenty-six articles were included in the review. Four hundred eighty-two pTCBIs have been reported in the literature. Major complications including skin breakdown, wound dehiscence, hematoma, seroma, and inability to use the device occurred in 5.2% of patients. Minor complications including pain and self-resolving erythema at the implant site occurred in 13.1% of the patients. The weighted mean pure-tone average gain of the two included devices was 28.4 ± 2.1 dB and the mean speech reception threshold gain was 32.9 ± 3.9 dB. Favorable quality-of-life scores have been demonstrated with pTCBIs. pTCBIs are a viable alternative to percutaneous devices in a carefully selected group of patients. These devices have demonstrated good audiological outcomes, low morbidity, and high patient satisfaction.

Investigating the race for the surface and skin integration in clinically retrieved abutments with two-photon microscopy

Bone conduction hearing implants can rehabilitate some types of hearing loss. A hydroxyapatite (HA)-coated skin-penetrating abutment was developed to allow for soft tissue preservation and increased skin-abutment adherence. Inflammation is thought to relate to bacterial infection of pockets around the abutment. Upon integration, the host’s ability to cover the abutment surface (“race for the surface”), and thus control and prevent competitive bacteria from colonizing it, is improved. However, the attachment mechanisms behind it are not clear. In this study, we applied two-photon microscopy to visualize tissue attachment on abutments retrieved from patients. Skin integration markers were validated and applied to four HA-coated abutments. Evidence of skin integration was found, including the presence of hemidesmosomes, a basement membrane, dermal collagen and vascularization. Cases with clinical signs of severe inflammation and evident biofilm formation showed limited skin integration based on these indicators, confirming the applicability of the “race for the surface” model.

The Use of Cone Beam Computed Tomography in Assessing the Insertion of Bone Conduction Hearing Implants.

This study aimed to compare postoperative cone beam CT (CBCT) imaging to implant stability quotient (ISQ) measurement and direct caliper measurements as a suitable technique to assess bone conduction hearing implant (BCHI) seating and insertion depth. In vitro, BCHIs were completely (n = 9) and partially inserted (n = 9) in bone blocks of different densities and subsequently scanned. Scans were processed using 3DSlicer 4.3.1 and Mathematica 10.3. ISQ measurements were obtained for all BCHIs mounted with different abutment lengths (9, 12, and 14 mm). CBCT imaging was performed for patients with a clinical indication. In vitro, 95% prediction intervals for partially inserted and completely inserted BCHIs were determined. ISQ values significantly decreased with partial insertion, low-density artificial bone, and longer abutment lengths. Evaluation of in vitro and in vivo 3D models allowed for assessment of insertion depth and inclination. CBCT imaging allows to study implant seating and insertion depth after BCHI surgery. This can be useful when visual confirmation is limited. It is possible to distinguish a partial BCHI insertion from a complete insertion in artificial bone blocks. This technique could prove to be a valuable research tool. In vitro, ISQ values for Ponto BCHIs relate to abutment length, insertion depth, and artificial bone density.

Audiological Results in SSD With an Active Transcutaneous Bone Conduction Implant at a Retrosigmoidal Position.

One option for patients with single sided deafness (SSD) who experience problems with insufficient hearing in different surroundings is the treatment with percutaneous bone-anchored hearing aids. Common medical problems associated to a skin penetrating abutment can be avoided by active transcutaneous bone conduction hearing implants. The purpose of our study was to evaluate the benefit of an active transcutaneous bone conduction hearing implant in patients with SSD. Patients suffering from SSD who are implanted with an active transcutaneous bone conduction hearing implant in retrosigmoidal position were audiologically analyzed. The audiological test battery included air and bone conduction thresholds, word recognition score (WRS) in quiet and speech intelligibility (Oldenburg Sentence Test [OLSA]) in noise. Patient satisfaction was evaluated with the Abbreviated Profile of Hearing Aid Benefit (APHAB) and the Bern-Benefit in Single-Sided Deafness (BBSS) questionnaire. The monosyllable WRS and the signal-to-noise ratio (SNR) assessed by the OLSA was significantly better in all aided conditions. Also, the APHAB categories ease of communication and reverberation and the average benefit in the BBSS improved significantly if using the device. The Bonebridge is a transcutaneous alternative to the well-established percutaneous bone conducting devices in patients with single sided deafness. An improvement in hearing in noise and quiet as well as a decrease of the head shadow effect can be expected.

UK tertiary centre experience of outcomes from osseointegrated transcutaneous magnetic bone conduction hearing system implanted in twenty-five patients using a linear incision technique.

Bone-anchored hearing aids are an established means of managing both single-sided and bilateral conductive or mixed hearing loss. Magnetic bone conduction hearing implants have been designed to provide an alternative bone conduction system to the existing aids which couple to a traditional percutaneous abutment. The BAHA® Attract (Cochlear Bone Anchored Solutions AB. Molnlycke, Sweden) system, which has been reviewed, uses an osseointegrated titanium implant coupled to an implantable magnet. This article is protected by copyright. All rights reserved.

Complications and parent satisfaction in pediatric osseointegrated bone‐conduction hearing implants

To assess long-term complication rate and parental satisfaction of osseointegrated bone conduction hearing implants (OBCHIs). Retrospective chart review of children undergoing OBCHIs. A retrospective chart review of children undergoing OBCHIs for the treatment of conductive, mixed, and single-sided sensorineural hearing loss in children. Forty-five subjects were identified with 0.3 to 10.4 years of follow-up. The mean/median age and age range at implant were 9.0/7.8 and 1.7 to 19.1 years. The underlying hearing loss for the cohort included conductive (N = 30), sensorineural (N = 7), and mixed (N = 8) hearing loss. Conductive hearing loss, caused by aural atresia (62.9), was the most common indication for implantation. Fifty-eight complications occurred in 29 subjects, most related to skin infection or overgrowth. Seventeen events required revision surgery, and 18 required oral antibiotics and/or office-based cauterization. Children under the age of 5 years were more likely to have failure of osseointegration or require revision surgery. Parents of 33 subjects underwent a phone interview; 76% rated the overall satisfaction as satisfied or very satisfied. A large percentage of children undergoing OBCHI develop postoperative complications, and up to 44% require revision surgery-a figure higher than generally reported and higher than in adults. No factors were found to adequately explain the higher complication rates in children compared to adults. Despite the occurrence of complications, parents viewed this device as satisfactory from many perspectives. 4. Laryngoscope, 127:2165-2170, 2017.

Minimally Invasive Ponto Surgery compared to the linear incision technique without soft tissue reduction for bone conduction hearing implants: study protocol for a randomized controlled trial

BackgroundOver the last years, less invasive surgical techniques with soft tissue preservation for bone conduction hearing implants (BCHI) have been introduced such as the linear incision technique combined with a punch. Results using this technique seem favorable in terms of rate of peri-abutment dermatitis (PAD), esthetics, and preservation of skin sensibility. Recently, a new standardized surgical technique for BCHI placement, the Minimally Invasive Ponto Surgery (MIPS) technique has been developed by Oticon Medical AB (Askim, Sweden). This technique aims to standardize surgery by using a novel surgical instrumentation kit and minimize soft tissue trauma.MethodsA multicenter randomized controlled trial is designed to compare the MIPS technique to the linear incision technique with soft tissue preservation. The primary investigation center is Maastricht University Medical Center. Sixty-two participants will be included with a 2-year follow-up period. Parameters are introduced to quantify factors such as loss of skin sensibility, dehiscence of the skin next to the abutment, skin overgrowth, and cosmetic results. A new type of sampling method is incorporated to aid in the estimation of complications. To gain further understanding of PAD, swabs and skin biopsies are collected during follow-up visits for evaluation of the bacterial profile and inflammatory cytokine expression.The primary objective of the study is to compare the incidence of PAD during the first 3 months after BCHI placement. Secondary objectives include the assessment of parameters related to surgery, wound healing, pain, loss of sensibility of the skin around the implant, implant extrusion rate, implant stability measurements, dehiscence of the skin next to the abutment, and esthetic appeal. Tertiary objectives include assessment of other factors related to PAD and a health economic evaluation.DiscussionThis is the first trial to compare the recently developed MIPS technique to the linear incision technique with soft tissue preservation for BCHI surgery. Newly introduced parameters and sampling method will aid in the prediction of results and complications after BCHI placement.Trial registrationRegistered at the CCMO register in the Netherlands on 24 November 2014: NL50072.068.14. Retrospectively registered on 21 April 2015 at ClinicalTrials.gov: NCT02438618. This trial is sponsored by Oticon Medical AB.Electronic supplementary materialThe online version of this article (doi:10.1186/s13063-016-1662-0) contains supplementary material, which is available to authorized users.

The Bonebridge Bone Conduction Hearing Implant: indication criteria, surgery and a systematic review of the literature.

Hearing aids and implants employing bone conduction (BC) stimulation have a long tradition in the treatment of conductive or mixed hearing loss, with their indications being extended in the 2000s to include single-sided deafness (SSD). Existing percutaneous bone conduction implants (BCI) provide significant audiological gain but are associated with a high rate of complications. This has led to the development of passive transcutaneous BCIs; however, audiological benefit may be compromised. An active transcutaneous BCI, the Bonebridge, was recently introduced and first implanted in 2011 as part of a clinical trial. To introduce and assess the safety and effectiveness of the Bonebridge for individuals with conductive or mixed hearing loss, and SSD. Systematic review. The Cochrane Library, PubMed and OVIDSP (MEDLINE) and EMBASE were searched to identify papers on the Bonebridge published as of June 2014. No exclusion criteria were set on publication language, study design or reported outcomes. The literature found was supplemented by presentations from relevant conferences. Study selection, data extraction and study quality assessment were carried out by a single reviewer with any uncertainties resolved with consulting a second reviewer. Studies were synthesised narratively and results were tabulated. A total of 29 studies, 17 published and 12 presentations, were identified. The highest quality evidence was from three single-arm trials. In those assessing the safety of implantation, 6 of 117 patients experienced a minor adverse event with superficial revision surgery being required in one case. Studies demonstrated improved hearing thresholds and speech recognition with the Bonebridge when compared to no aiding in adults and children with either type of hearing loss. This was reflected in high device satisfaction rates. Data collected in the second year of device use further suggest the benefit to remain constant. The transcutaneous BCI system Bonebridge provides a valuable and stable audiological benefit to patients suffering from conductive or mixed hearing loss and SSD. With its active transcutaneous design, the Bonebridge offers a lower complication rate to percutaneous systems and higher and more reliable hearing gain compared to other transcutaneous or percutaneous systems. Moreover, the fast activation of the implant system enables the recipient of the system to benefit in a short time frame postoperatively from the intervention.

Safety and effectiveness of the Vibrant Soundbridge in treating conductive and mixed hearing loss: A systematic review.

For many years, the therapeutic approach for conductive and/or mixed hearing loss has consisted of middle ear surgery with replacement of defect ossicles, and if possible the application of a hearing aid. Advances in technology have led to the introduction of electronmagnetic active implantable devices such as the Vibrant Soundbridge (VSB). With its various coupling techniques for different pathophysiological situations in the middle ear, the VSB offers greater improvement in the hearing performance of affected persons. PubMed, OvidSP (MEDLINE), EMBASE (DIMDI), the National Institue for Health research (NIHR) Centre for Reviews and Dissemination (including the National Health Service Economic Evaluation Database, Database of Abstracts of Reviews of Effects, and Health Technology Assessment), and the Cochrane Library were searched to identify articles published between January 2006 and April 2014 that evaluated the safety and effectiveness of the VSB in comparison to no intervention, bone conduction hearing implants (BCHI), and middle ear surgery plus hearing aids for adults and children with conductive or mixed hearing loss. Study selection and data extraction was carried out by multiple reviewers. Study quality was assessed using the Oxford Centre for Evidence-Based Medicine levels of evidence (2011); and a checklist available from the Evidence Analysis Library, Academy of Nutrition and Diabetics. Thirty-six publications were identified: 19 on VSB outcomes in 294 individuals, 13 on BCHI outcomes in 666 individuals, and four on middle ear surgery plus hearing aid outcomes in 43 individuals. Two systematic reviews were also identified. Heterogeneous outcome measures made it difficult to summarize data. In general, the VSB proved to be safe and effective when compared to no intervention and BCHI, and provided more and consistent hearing gain compared to middle ear surgery plus conventional hearing aids. As demonstrated in the literature, the VSB as an active device offers an effective alternative for patients with various middle ear pathologies, particularly with mixed hearing loss and failed previous tympanoplasties when classical ossiculoplasty could not provide enough functional gain. This new strategy in hearing rehabilitation has led to an improved quality of hearing and life. Laryngoscope, 126:1451-1457, 2016.

Bonebridge Implantation for Conductive Hearing Loss in a Patient with Oval Window Atresia

The occurrence of oval window atresia is a rare anomaly with conductive hearing loss. Traditional atresia surgeries involve challenging surgical techniques with risks of irreversible inner ear damage. Recent reports on Bonebridge (Medel, Innsbruck, Austria), a novel implantable bone conduction hearing aid system, assert that the device is safe and effective for conductive hearing loss. We present a case of Bonebridge implantation in an eight-year-old girl with bilateral oval window atresia.

Can the Hydroxyapatite-Coated Skin-Penetrating Abutment for Bone Conduction Hearing Implants Integrate with the Surrounding Skin?

Percutaneous implants, such as bone conduction hearing implants, suffer from complications that include inflammation of the surrounding skin. A sealed skin-abutment interface can prevent the ingress of bacteria, which should reduce the occurrence of peri-abutment dermatitis. It was hypothesized that a hydroxyapatite (HA)-coated abutment in conjunction with soft tissue preservation surgery should enable integration with the adjacent skin. Previous research has confirmed that integration is never achieved with as-machined titanium abutments. Here, we investigate, in vivo, if skin integration is achievable in patients using a HA-coated abutment. One titanium abutment (control) and one HA-coated abutment (case) together with the surrounding skin were surgically retrieved from two patients who had a medical indication for this procedure. Histological sections of the skin were investigated using light microscopy. The abutment was qualitatively analyzed using scanning electron microscopy. The titanium abutment only had a partial and thin layer of attached amorphous biological material. The HA-coated abutment was almost fully covered by a pronounced thick layer of organized skin, composed of different interconnected structural layers. Proof-of-principle evidence that the HA-coated abutment can achieve integration with the surrounding skin was presented for the first time.

New developments in bone-conduction hearing implants: a review.

The different kinds of bone-conduction devices (BCDs) available for hearing rehabilitation are growing. In this paper, all BCDs currently available or in clinical trials will be described in categories according to their principles. BCDs that vibrate the bone via the skin are referred to as skin-drive devices, and are divided into conventional devices, which are attached with softbands, for example, and passive transcutaneous devices, which have implanted magnets. BCDs that directly stimulate the bone are referred to as direct-drive devices, and are further divided into percutaneous and active transcutaneous devices; the latter have implanted transducers directly stimulating the bone under intact skin. The percutaneous direct-drive device is known as a bone-anchored hearing aid, which is the BCD that has the largest part of the market today. Because of some issues associated with the percutaneous implant, and to some extent because of esthetics, more transcutaneous solutions with intact skin are being developed today, both in the skin-drive and in the direct-drive category. Challenges in developing transcutaneous BCDs are mostly to do with power, attachment, invasiveness, and magnetic resonance imaging compatibility. In the future, the authors assume that the existing percutaneous direct-drive BCD will be retained as an important rehabilitation alternative, while the transcutaneous solutions will increase their part of the market, especially for patients with bone-conduction thresholds better than 35 dB HL (hearing level). Furthermore, the active transcutaneous direct-drive BCDs appear to be the most promising systems, but to establish more detailed inclusion criteria, and potential benefits and drawbacks, more extensive clinical studies are needed.

C202 埋め込み型骨導補聴器の経皮伝送法の最適化および音質評価(C2-1 医療・福祉機器)

C202 埋め込み型骨導補聴器の経皮伝送法の最適化および音質評価(C2-1 医療・福祉機器)

First European Multicenter Results With a New Transcutaneous Bone Conduction Hearing Implant System

To investigate safety and efficacy of a new transcutaneous bone conduction hearing implant, over a 3-month follow-up period. Prospective, single-subject repeated-measures design in which each subject serves as his/her own control. Departments of Otolaryngology at 4 hospitals in Germany and Austria. Subjects were 12 German-speaking adults who suffered from conductive or mixed hearing loss. The upper bone conduction threshold limit was set to 45 dB HL at frequencies between 500 Hz and 4 kHz. Implantation of a transcutaneous bone conduction hearing implant. Subjects' speech perception (word recognition scores and SRT 50%) and audiometric thresholds (air conduction, bone conduction and sound field at frequencies 500 Hz to 8 kHz) were assessed preoperatively, 1 month postoperatively and 3 months postoperatively. The subjects were monitored for adverse events and given a questionnaire to assess their satisfaction levels. Speech perception as measured by word recognition scores and SRT 50% improved on average about 78.8% and 25 dB HL, respectively, 3 months after implantation. Aided thresholds also improved postoperatively at all tested frequencies and continued to improve from 1 to 3 months postoperatively. Air conduction and bone conduction thresholds showed no significant changes, confirming that subjects' residual unaided hearing was not deteriorated by the treatment. Only minor adverse events were reported and resolved by the end of the study. The new transcutaneous bone conduction implant was demonstrated to be safe and effective in adults up to 3 months of device use.

A New Semi-Implantable Transcutaneous Bone Conduction Device

Patients with air-bone-gaps that cannot be corrected successfully by tympanoplasty or with mixed hearing loss may be treated with bone conducting hearing aids. Their disadvantages are the obvious external fixation components or the biological and psychosocial problems of open implants. We have developed a new partially implantable Bone Conduction Hearing Device (BCHD) without a percutaneous abutment and have been using them clinically for over 6 years. The principle of these BCHD is a magnetic coupling and acoustic transmission between implanted and external magnets. The goal of this study was to evaluate its clinical and audiologic results in patients with unilateral or bilateral congenital aural atresia. Magnets are implanted into shallow bone beds in a 1-step procedure. The skin above the magnets is slightly thinned. The external device fixed with counter magnets in a base plate. Twenty-one patients who have been implanted due to congenital atresia showed up for this follow-up study. The follow-up period was 19.3 ± 12.2 months, with a range of 0.2 to 46.6 months. The average age of the patients at the time of implantation was 12.4 years with a wide range from 6.0 to 50.0 years. The average hearing gain was 31 ± 8 dB, and the suprathreshold word recognition tests increased by 57% ± 23%. Strength of the magnetic force that the patients had chosen themselves measured 0.9 ± 0.4 N with a range from 0.3 to 1.8 N. Skin thickness over the implants measured sonographically was 3.9 ± 0.8 mm (range, 2.5-5.6 mm). This new bone conducting hearing device only needs one operation, has a very low risk for complication, and a hearing gain similar to other bone conducting hearing aids. We have found high comfort and safety of this system and conclude that it could be a valuable alternative to other conventional or percutaneous bone conducting hearing solutions.