Long-term Results of 185 Consecutive Osseointegrated Hearing Device Implantations: A Comparison Among Children, Adults, and Elderly

Paediatric percutaneous bone anchored hearing aid implant failures: Comparing the experience of a tertiary centre with a systematic review of the literature and meta-analysis

BACKGROUND

Despite the proven audiological benefits of Percutaneous Bone Anchored Hearing Aids (BAHAs) in paediatric patients with conductive or mixed hearing loss, their adoption has been limited due to concerns over implant failure and associated complications. This paper conducts a systematic review and meta-analysis to assess the prevalence of implant failure in paediatric populations, combined with a case series from our tertiary referral centre.

METHODS

A comprehensive literature search identified 562 articles, from which 34 were included in the review, covering 1599 implants in 1285 patients. Our retrospective case series included consecutive patients from our tertiary referral centre who underwent percutaneous BAHA implantation from 2003-2019.

RESULTS

Meta-analysis revealed an overall implant failure rate of 11%, predominantly attributed to traumatic extrusion. Our retrospective case series comprised 104 implantations in 76 patients, with a 4.8% failure rate.

DISCUSSION

Factors contributing to the lower-than-expected failure rates in the case series likely included consistent use of 4 mm fixtures from a single manufacturer and older age at implantation. The study underscores the need for standardised reporting formats in bone conduction implants research, given the systematic review's limitations in study design heterogeneity, especially with the expected rise in the adoption of novel active devices.

Audiologic outcomes and complications of active middle ear implantation in older adults

BACKGROUND

A few studies have reported the use of middle ear implants (MEIs) in older adults.

OBJECTIVES

To evaluate the audiologic outcomes and postoperative complications of MEIs in older adults.

METHODS

This retrospective study reviewed audiologic data and medical records from a single referral centre. We identified 34 patients aged ≥65 years who underwent middle ear implantation using the Vibrant Soundbridge^TM device. Preoperative audiometric testing and postoperative aided audiometric testing were performed to evaluate the functional hearing gain at 1 year postoperatively. Patients were divided into 2 groups depending on whether they underwent explantation because of poor hearing benefit.

RESULTS

Follow-up duration ranged from <1 to 5.3 years. The functional gain with MEIs significantly improved relative to the preoperative air conduction thresholds at 0.5, 1, 2, and 4 kHz. Eight patients underwent explantation and 7 lost their external audio processor devices. Those who removed their implants because of the poor hearing (group 1) showed significantly worse hearing thresholds at 1 kHz and speech discrimination scores than the others (group 2).

CONCLUSIONS AND SIGNIFICANCE

MEIs for auditory rehabilitation can provide improved speech recognition and significant functional gains in older adults. Patients must be given appropriate preoperative explanations regarding the expected outcomes.

The efficacy of bone-anchored hearing implant surgery in children: A systematic review

OBJECTIVE

To evaluate the efficacy of Bone-Anchored Hearing implants (BAHIs) in children and to elucidate the usage and outcomes of new surgical techniques and implants in this specific population.

DATA SOURCES

Embase and PubMed.

STUDY SELECTION

We identified studies evaluating surgical outcomes of BAHIs in children. Retrieved articles were screened using predefined inclusion and exclusion criteria. Critical appraisal included directness of evidence and risk of bias. Studies that successfully passed critical appraisal were included.

DATA EXTRACTION

Outcome measures included patient demographics, follow-up time, surgical technique (one-versus two-stage surgery), tissue handling technique (reduction versus preservation), type of implant used, and complications.

DATA SYNTHESIS

We selected 20 articles published between 2000 and 2017 for data extraction, encompassing 952 implanted BAHIs. The overall mean age at implantation was 8.6 years (range, 2-21 years). Adverse soft-tissue reactions occurred in 251 of the 952 implants (26.4%; range 0%-89% across studies). Revision surgery was performed in 16.8% (142 of the 845) of the implants. The total rate of implant loss, i.e. caused by OIF (n = 61), trauma (n = 33), recurrent infection (n = 15), elective removal due to insufficient benefit (n = 1), cosmetic reasons (n = 1), or unknown reason (n = 16), was 13.3% of the implants (127 out of 952; range 0%-40% across studies). Differences are seen in the type of implants used; wide-diameter implants seem to be superior in terms of implant survival, and similar in terms of adverse skin reactions, while one-stage surgery and soft-tissue preservation do not seem to result in higher implant loss rates or increased adverse skin reactions based upon limited amounts of literature.

CONCLUSION

In general, BAHIs are a safe method for hearing rehabilitation in children, although large differences between studies are observed. The outcomes of new surgical techniques and implant designs in the pediatric population seem promising, but more research is needed before definitive conclusions can be drawn.

Complications of bone-conduction hearing implants (BCHI) implantation surgery

PURPOSE

Bone-conduction Hearing Implants (BCHIs) are surgically implanted hearing devices. As the implantation surgery involves soft tissue dissection through periosteum and drilling of skull, complications related to the skin and soft tissue remain common despite several modifications of surgical techniques over the years. This study aims to evaluate a single centre's BCHI implantation complication rates over time, identify the effects of surgical modifications, and compare these to data from the literature.

MATERIALS AND METHODS

A retrospective case review was performed on all patients who received BCHI implantation from 2013 to 2018. 11 complication rates over time were recorded. Changes to practice occurring during the study period were also recorded and their effects on complication rates were identified. A literature search was performed to identify the complication rates reported in the literature and compared with that of our cohort.

RESULTS

162 BCHI implantations were performed over the 5 years. 23 articles were included in the study after the literature review process. In our cohort, complications related to skin and soft tissue were most common, which was in line with that reported in the literature. Complication rates have overall decreased following the introduction of innovative practices, including adoption of minimally-invasive single-stage procedures and the training of specialist nurses.

CONCLUSIONS

In this study we have highlighted the changes in complication rates of BCHI implantation over time at a single centre with reference to changes in clinical practice. Continued review of practice and on-going technological developments will facilitate continued reductions in complications of BCHI surgery.

Medical, Technical and Audiological Outcomes of Hearing Rehabilitation with the Bonebridge Transcutaneous Bone-Conduction Implant: A Single-Center Experience

Bone-conduction implants are a standard therapeutic option for patients with conductive, unilateral, or mixed hearing loss who either do not tolerate conventional hearing aids or can benefit from surgery. The aim of this study was to evaluate long-term medical and technical outcomes, and audiological results with the Bonebridge transcutaneous bone-conduction implant. This retrospective study included all patients implanted with a bone-conduction hearing implant at a tertiary medical referral center between March 2012 and October 2018. Medical and technical outcomes included the mean length of implant usage, medical and technical complications (skin and wound infection, lack of benefit, technical failure), explantations and revisions, coupling approaches, implant failure rate, implant survival and the implant loss for added follow-up years. Auditory results were measured by functional hearing gain and the Freiburger monosyllabic test at 65 dB sound pressure level. Sixty-four patients were included in the study; five of these were implanted bilaterally (69 devices). Five unilaterally implanted patients were lost to follow-up. The mean follow-up was 27.1 months (range: 0.2 months–6.3 years). The mean implant usage was 25.9 months (range: 0.2 months–6.3 years). Fifty-seven implants (89.1%) were in use at the end of the follow-up period. Complications occurred in six ears (9.4%). Five implants (7.8%) were explanted without reimplantation. Device failure occurred in one implant (1.6%), which was possibly caused by recurrent head trauma. The rate of implant loss due to technical device failure (damage to device) was 1 per 72 follow-up years. The mean improvement on the Freiburger monosyllabic test (52.1%, p = 0.0001), and in functional hearing gain across frequencies (26.5 dB, p = 0.0001) was significant. This single-center follow-up reveals the medical and technical reliability of a transcutaneous bone-conduction implant for hearing rehabilitation because complication and revision rates were low. The majority of patients still used the device at the end of the observation period. Implantation resulted in favorable hearing outcomes in comparison to that of unaided conditions. Cautious patient selection mainly regarding co-morbidities, the history of chronic otologic diseases and proper surgical technique seems to be crucial in reducing complications.

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

OBJECTIVE

This study examines the incidence and management of traumatic loss or osseointegration failure of percutaneous bone conduction implants in children.

STUDY DESIGN

Case series.

SETTING

Pediatric tertiary care institution.

PATIENTS

Children who underwent percutaneous osseointegrated implant placement from 1996 to 2016.

INTERVENTIONS

Clinical evaluation and revision surgery after implant loss.

MAIN OUTCOME MEASURES

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.

RESULTS

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.

CONCLUSION

Traumatic injury or osseointegration failure leads to loss of percutaneous bone conduction implants in approximately 15% of children. Revision surgery is often successful.

Subdural Hematoma: A Rare Adverse Complication From Bone-Anchored Hearing Aid Placement

OBJECTIVE

Bone-anchored hearing aids (BAHA) are bone conduction hearing aids commonly implantated by Ear, Nose, and Throat surgeons. We present the first documented case of a subdural hematoma secondary to primary fixation of a BAHA.

PATIENT

We present a 65-year-old male patient undergoing a left sided BAHA for bilateral chronic ear infections and difficulty wearing conventional hearing aids. The procedure was uneventful, however, the patient developed a postoperative large acute left temporoparietal intracerebral hematoma associated with an ipsilateral acute subdural hematoma. This required emergency transfer to the local tertiary neurosurgical center for a left decompressive craniotomy and evacuation of the hematoma.

RESULTS

The patient required a prolonged stay on an intensive care unit and was eventually discharged to the community for on-going neurological rehabilitation.

CONCLUSION

This is a rare and devastating complication BAHA surgery. Otologist, general ENT surgeons, and neurosurgeons should be aware of this life-threatening complication of BAHA surgery.

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

OBJECTIVE

To investigate skin-related postoperative complications from tissue preservation approaches in percutaneous bone conduction device (BCD) implantations.

DATA SOURCES

PubMed, Embase, and Cochrane Library.

STUDY SELECTION

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.

DATA EXTRACTION

Outcome measures included patient demographics, surgery time, follow-up time, and complications reported by Holgers classification.

DATA SYNTHESIS

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.

CONCLUSION

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.

A comparison study of complications and initial follow-up costs of transcutaneous and percutaneous bone conduction devices

Background:

The percutaneous osseointegrated bone conduction device can be associated with more soft tissue complications when compared to the magnetic transcutaneous osseointegrated bone conduction device. This study aimed to determine whether fewer soft tissue complications may result in the transcutaneous osseointegrated bone conduction device being a lower cost option in hearing rehabilitation.

Methods:

This retrospective case note review included adult patients who underwent implantation with the transcutaneous Cochlear Attract (n = 22) or percutaneous Cochlear DermaLock (n = 25) bone-anchored hearing aids between September 2013 and December 2014. The number of post-operative clinic appointments, complications and treatments undertaken, and calculated cost average, were compared between the two groups.

Results:

Although the transcutaneous device was slightly more expensive than the percutaneous device, the percutaneous device was associated with a greater number of soft tissue complications and, as a result, the percutaneous device had significantly higher follow-up costs in the first six months following surgery.

Conclusion:

The transcutaneous osseointegrated bone conduction device may represent a more cost-effective method of hearing rehabilitation compared to the percutaneous osseointegrated bone conduction device.

Baha implant as a hearing solution for single-sided deafness after retrosigmoid approach for the vestibular schwannoma: surgical results

Skull base tumors and, in particular, vestibular schwannoma (VS) are among the etiological reasons for single-sided deafness (SSD). Patients with SSD have problems in understanding speech in a noisy environment and cannot localize the direction of sounds. Baha is one of the most frequently used systems for SSD compensation. Out of 38 patients with SSD after retrosigmoid removal of VS who underwent testing with Baha softband, 16 were satisfied and were indicated for Baha implantation. Two surgical approaches have been used-the Nijmegen linear incision technique with subdermal thinning (Group I, implant BI300) and fast surgery technique without subdermal thinning (Group II, implant BIA400). The duration of the surgery, the implant stability measured by Ostell, and skin or soft tissue reactions in long range follow-up were evaluated and compared between Group I and II. There was a difference in duration of surgery, in Group II procedures averaged significantly faster (p > 0.001). In both groups, there was a similar trend of the gradual increase of implant stability. In the Group I and II, there was comparable rate of the skin or soft tissue reactions grade 0, I, II, or III. We have proved Baha to be a suitable possibility for SSD patients after the removal of VS, regardless of the approach. After the retrosigmoid approach to the VS, the key step of Baha implantation must be to reach intact healthy bone to avoid implantation into scar tissue.

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).

Percutaneous bone-anchored hearing implant surgery: inside or outside the line of incision?

The objective of this historical cohort study was to compare soft tissue reactions in adults after bone-anchored hearing implant (BAHI) surgery when the percutaneous implant is placed inside or outside the line of incision. All adult patients who received a percutaneous BAHI between 1 January 2010 and 31 January 2014 in our tertiary referral centre were identified. Patients were selected if operated by two surgeons, who perform the same standardised linear incision technique with one of them placing the implant outside the incision while the other prefers placement inside the line of incision. A total of 202 patients and 211 implants were included in the case analysis. The results showed the registration of a soft tissue reaction Holgers ≥1 in 47 implants (49.0 %) placed outside the incision compared to 70 implants (60.9 %) which were placed inside the line of incision. An adverse soft tissue reaction, Holgers ≥2, was noticed in 17 implants (17.7 %), respectively, 20 implants (17.4 %). No significant differences were found between the two groups for both the presence of soft tissue reactions Holgers ≥1 (p = 0.322) and a Holgers score ≥2 (p = 0.951). During the follow-up three implants were lost (1.4 %) and in 18 of 211 implants one or multiple revisions were performed (8.5 %). In conclusion, this study did not show any differences in the presence of postsurgical (adverse) soft tissue reactions between placement of the percutaneous BAHI inside or outside the line of incision.

Percutaneous bone-anchored hearing implant surgery: dermatome versus linear incision technique

The objective of this historical cohort study is to identify if there are differences in soft tissue reactions and skin thickening between implantation of the percutaneous bone-anchored hearing implant (BAHI) using the dermatome or linear incision technique. All adult patients who received a BAHI between August 2005 and January 2013 were selected. One surgeon performed all procedures and only the dermatome and linear incision technique were used. A total of 132 patients/implants were included and significantly more patients with risk factors were seen in the linear incision cohort. A soft tissue reaction Holgers ≥1 was present in 18 patients (40.9 %) in the dermatome compared to 36 patients (40.9 %) in the linear incision group. A Holgers ≥2 was noticed in 9 (20.5 %) and 19 (21.6 %) patients, respectively. Skin thickening was described in 14 (31.8 %) and 11 patients (12.5 %) in, respectively, the dermatome and linear incision cohort, which was a significant difference (p = 0.001). Nevertheless, therapeutic interventions were effective. In conclusion, there was no significant difference in (adverse) soft tissue reactions; however, skin thickening was more present in the dermatome technique. In addition, significantly more patients with risk factors were allocated to the linear incision technique. Based on these results, the linear incision is advocated as preferred technique.

Vibrant SoundBridge combined with auricle reconstruction for bilateral congenital aural atresia

OBJECTIVES

To report an integrating surgical method of Vibrant SoundBridge (VSB) implant and auricle reconstruction.

METHODS

4 cases of congenital bilateral external/middle ear malformation were enrolled. All of them were diagnosed as bilateral bony atresia and grade III microtia. Stapes vibroplasty was performed for all subjects in one operation with auricle reconstruction stage 3. The clinical information and hearing outcomes were analyzed.

RESULTS

Satisfied aesthetic outcomes were confirmed by sculptured outline and symmetric shape on both sides. Mean improvement in hearing threshold with VSB activation was 25.9 dB HL, while mean scores of speech recognition test were 21.8-46.3%.

CONCLUSION

Combined surgical method of VSB implant and aesthetic reconstruction is safe and efficient for congenital external/middle ear malformation case.

Laser-Modified Surface Enhances Osseointegration and Biomechanical Anchorage of Commercially Pure Titanium Implants for Bone-Anchored Hearing Systems

Osseointegrated implants inserted in the temporal bone are a vital component of bone-anchored hearing systems (BAHS). Despite low implant failure levels, early loading protocols and simplified procedures necessitate the application of implants which promote bone formation, bone bonding and biomechanical stability. Here, screw-shaped, commercially pure titanium implants were selectively laser ablated within the thread valley using an Nd:YAG laser to produce a microtopography with a superimposed nanotexture and a thickened surface oxide layer. State-of-the-art machined implants served as controls. After eight weeks' implantation in rabbit tibiae, resonance frequency analysis (RFA) values increased from insertion to retrieval for both implant types, while removal torque (RTQ) measurements showed 153% higher biomechanical anchorage of the laser-modified implants. Comparably high bone area (BA) and bone-implant contact (BIC) were recorded for both implant types but with distinctly different failure patterns following biomechanical testing. Fracture lines appeared within the bone ~30-50 μm from the laser-modified surface, while separation occurred at the bone-implant interface for the machined surface. Strong correlations were found between RTQ and BIC and between RFA at retrieval and BA. In the endosteal threads, where all the bone had formed de novo, the extracellular matrix composition, the mineralised bone area and osteocyte densities were comparable for the two types of implant. Using resin cast etching, osteocyte canaliculi were observed directly approaching the laser-modified implant surface. Transmission electron microscopy showed canaliculi in close proximity to the laser-modified surface, in addition to a highly ordered arrangement of collagen fibrils aligned parallel to the implant surface contour. It is concluded that the physico-chemical surface properties of laser-modified surfaces (thicker oxide, micro- and nanoscale texture) promote bone bonding which may be of benefit in situations where large demands are imposed on biomechanically stable interfaces, such as in early loading and in compromised conditions.

Switching from a percutaneous to a transcutaneous bone anchored hearing system: the utility of the fascia temporalis superficialis pedicled flap in case of skin intolerance

OBJECTIVES

To present the option to use a Fascia Temporalis Superficialis pedicled flap for the implantation of a transcutaneous magnetic osseointegrated auditory implant in selected revision procedures.

BACKGROUND

Osseointegrated auditory implants represent a reliable option for patients. Skin intolerance and aesthetic issue are two clear limitations of percutaneous system. Magnetic transcutaneous devices have been developed to overcome such drawbacks. The current new experience of such a device shows that they are well tolerated in primary cases. However, switching from a previous percutaneous system raises the question of skin tolerance. Hence, previous implanted abutments with skin penetration and skin reduction are more likely cause to skin intolerance and complication.

METHODS

We described here the option to use a Fascia Temporalis Superficialis flap to cover the implanted magnet.

CONCLUSION

When switching from percutaneous osseointegrated auditory implant to transcutaneous system in case of high risk of skin intolerance, this procedure may provide sufficient tissue coverage to prevent skin intolerance, pain and delayed extrusion.