Implantable Bone Conduction and Bone-Anchored Hearing Aids
*Medicare has a policy.
Unilateral Conductive or Mixed Hearing Loss
Unilateral implantable bone conduction (bone-anchored) hearing aid may be considered medically necessary as an alternative to an air-conduction hearing aid in patients 5 years of age and older with a conductive or mixed hearing loss who meet ONE of the following medical criteria:
Meet the following audiologic criteria:
Bilateral Conductive or Mixed Hearing Loss
Bilateral implantable bone conduction (bone-anchored) hearing aid(s) may be considered medically necessary as an alternative to an air-conduction hearing aid in patients 5 years of age and older who meet the above audiologic criteria, AND have a symmetrically conductive or mixed hearing loss as defined by:
Single-sided Sensorineural Deafness and Normal Hearing in the Other Ear
An implantable bone-conduction (bone-anchored) hearing aid may be considered medically necessary as an alternative to a contralateral routing of sound (CROS) air-conduction hearing aid in patients 5 years of age and older with single-sided sensorineural deafness and normal hearing in the other ear.
Non-implanted Bone-conduction (bone-anchored) Hearing Aid
A BAHA® sound processor worn on the skull with a BAHA® Softband™ may be considered medically necessary in children under 5 years old who meet the conductive or mixed hearing loss criteria (see above), as an alternative to an air conduction hearing aid. The non-implanted use of the BAHA sound processor may be implemented as a pre-surgical trial in children under 5 years of age. (See Benefit Application).
Other Uses of implanted bone-conduction/bone-anchored hearing aids
Use of implantable bone-conduction (bone-anchored) hearing aids, including use in patients with bilateral sensorineural hearing loss is considered investigational.
Partially implantable magnetic bone conduction hearing systems using magnetic coupling for acoustic transmission (e.g. Otomga®Alpha 1, BAHA® Attract) are considered investigational.
A bone-conduction (bone-anchored) hearing aid is considered investigational for all other indications when the medical and audiologic criteria in this policy are not met; whether the device is attached to an implanted abutement or worn externally with a headband or softband.
In patients being considered for implantable bone-conduction (bone-anchored) hearing aid(s), skull bone quality and thickness should be assessed for adequacy to ensure stability of the implant. Additionally, patients (or caregivers) must be able to perform proper hygiene to prevent infection and ensure the stability of the implants and percutaneous abutments. Surgical implantation of the BAHA® device is not FDA approved for children younger than 5 years of age.
Unique clinical circumstances may justify individual consideration for use of the bone-conduction (bone-anchored) sound processor with headband or softband before 5 years of age, based on a review of applicable medical records to verify the medical necessity criteria listed in this policy are met. (See Benefit Application).
Note: The Audiant bone conductor is a type of electromagnetic bone conduction hearing device. This product is no longer actively marketed. However, patients with existing Audiant devices may require replacement, removal, or repair.
Note: Cochlear implants, used for the treatment of severe to profound deafness are addressed in a separate medical policy. (See Related Policies)
Conventional external hearing aids can be generally subdivided into air-conduction hearing aids and bone-conduction hearing aids. Air-conduction hearing aids require the use of ear molds, which may be problematic in patients with chronic middle ear and ear canal infections, atresia of the external canal, or an ear canal that cannot accommodate an ear mold. Bone-conduction hearing aids function by transmitting sound waves through the bone to the ossicles of the middle ear. Implantable, bone-anchored hearing aids (BAHA) and a partially implantable system have been investigated as alternatives to conventional bone-conduction hearing aids for patients with conductive or mixed hearing loss or in patients with unilateral single-sided sensorineural hearing loss.
In children under 5 years of age the transcutaneous use of the BAHA®, where the bone conduction-type hearing aid is held against the skin behind the ear, or at another bony location of the skull, by pressure from a headband or softband, has been used. The headband is soft plastic while the softband is soft elastic with a plastic disc-like snap connector either modeled or sewn into the band. A BAHA® sound processor is attached to the plastic connector and the band/headband adjusted to the size of the individual's head, secured with a Velcro® fastener (Velcro USA Inc., Manchester, NH). (See Appendix).
Hearing loss is described as conductive, sensorineural, or mixed, and can be unilateral or bilateral. Normal hearing is the detection of sound at or below 20 dB (decibel). The American Speech Language Hearing Association (ASLHA) has defined the degree of hearing loss based on pure-tone average (PTA) detection thresholds as mild (20 to 40 dB), moderate (40 to 60 dB), severe (60 to 80 dB), and profound (equal to or greater than 80 dB). PTA is calculated by averaging the hearing sensitivities (ie, the minimum volume that the patient hears) at multiple frequencies (perceived as pitch), typically within the range of 0.25-8 kHz.
Sound amplification through the use of an air-conduction (AC) hearing aid can provide benefit to patients with sensorineural or mixed hearing loss. Contralateral routing of signal (CROS) is a system in which a microphone on the affected side transmits a signal to an air-conduction hearing aid on the normal or less affected side.
External bone-conduction hearing aids function by transmitting sound waves through the bone to the ossicles of the middle ear. The external devices must be closely applied to the temporal bone, with either a steel spring over the top of the head or with the use of a spring-loaded arm on a pair of spectacles. These devices may be associated with either pressure headaches or soreness.
The bone-anchored hearing aid (BAHA®) implant system works by combining a vibrational transducer coupled directly to the skill via a percutaneous titanium abutment that permanently protrudes through the skin. A sound processor (a hearing aid) attaches to the small titanium implant that is anchored in the temporal bone. Over a period of 3-6 months, the titanium fixture bonds with the surrounding tissue – a process known as osseointegration. The osseointegrated titanium fixture and abutment provide secure attachment of the sound processor allowing amplified and processed sound to be conducted via the skull bone directly to the cochlea. The lack of intervening skin permits the transmission of vibrations at a lower energy level than required for external bone-conducting hearing aids. Implantable bone-conduction hearing systems are primarily indicated for individuals with conductive or mixed sensorineural/conductive hearing loss, or as an alternative to an air-conduction hearing aid with CROS for individuals with unilateral sensorineural hearing loss.
BAHA® sound processors can also be used with the BAHA® Softband or headband. With this application there is no titanium implantation surgery. The sound processor is attached to the head using either a hard or soft headband. The amplified sound is transmitted transcutaneously to the bones of the skull for transmission to the cochlea, bypassing the outer and middle ear. This application may be used as a pre-surgical trial in children under 5 years of age.
Partially implantable magnetic bone-conduction hearing systems are available as an alternative to the bone-conduction hearing systems connected percutaneously via an abutment. With this technique, acoustic transmission occurs via magnetic coupling of the external sound processor and internally implanted device components. The bone-conduction hearing processor contains magnets that adhere externally to magnets implanted in shallow bone beds with the bone-conduction hearing implant. Since the processor adheres magnetically to the implant, there is no need for a percutaneous abutment to physically connect the external and internal components. To facilitate greater transmission of acoustics between magnets, skin thickness must be reduced to 4-5 mm over the implant when it is surgically placed.
There are 5 BAHA ® sound processors for use with the BAHA® auditory osseointegrated implant system manufactured by Cochlear Americas (Englewood, CO), that have received 510(k) clearance from the U.S. Food and Drug Administration (FDA):
The FDA cleared the BAHA® system for the following indications:
The BAHA® implant is FDA approved for use in children aged 5 years and older, and in adults.
BAHA® sound processors can also be used with the BAHA® Softband™. With this application, there is no implantation surgery. The sound processor is attached to the head using either a hard or soft headband. The amplified sound is transmitted transcutaneously to the cochlea through the bones of the skull. The non-surgical/transcutaneous application of the BAHA® processor using a headband or softband received FDA clearance in 2002 for use in children under the age of 5 years.
In November 2008, the OBC Bone Anchored Hearing Aid System (Oticon Medical, Kongebakken, Denmark) was cleared by the U.S. Food and Drug Administration (FDA) for marketing through the 510(k) process. Subsequently, additional bone conduction hearing systems have received 510(k) marketing clearance from the FDA including Otomag® (Sophono, Inc., Boulder, CO) and Ponto™ (Oticon Medical). The Ponto Pro processor can be used with the Oticon or BAHA® implants. In May 2011, Sophono, Inc. and Oticon Medical partnered to receive 510(k) marketing clearance from the FDA for the Otomag® Alpha 1(M), a partially implantable bone conduction hearing system. All of these devices were determined to be substantially equivalent to existing devices (e.g., the Xomed Audiant™, which was FDA cleared for marketing in 1986 but is no longer available). They share similar indications as the Cochlear Americas’ BAHA devices.
The 2 partially implantable magnetic bone-conduction devices that have received 510(k) clearance from FDA are:
Medical policies are systematically developed guidelines that serve as a resource for Company staff when determining coverage for specific medical procedures, drugs or devices. Coverage for medical services is subject to the limits and conditions of the member benefit plan. Members and their providers should consult the member benefit booklet or contact a customer service representative to determine whether there are any benefit limitations applicable to this service or supply. This policy does not apply to Medicare Advantage.
Benefit limitations regarding hearing aids may apply to these devices, specifically when the Implantable Bone- Conduction and Bone-Anchored Hearing Aid (BAHA®) device is used transcutaneously (on the surface of the skin of the head) held in place by a headband or softband and not implanted.
Usual frequency of replacement for BAHA parts
Adapted from Wisconsin Department of Health Services, available on line at: https://www.forwardhealth.wi.gov/WIPortal/Online%20Handbooks/Print/tabid/154/Default.aspx?ia=1&p=1&sa=28&s=2&c=10&nt=Cochlear+Implant+and+Bone-Anchored+Hearing+Aid+Surgeries. Last accessed February, 2015.
This policy was created in October 2012 and updated regularly based on searches of the MEDLINE database, most recently through January, 2015. The evidence related to the use of bone-anchored hearing aid (BAHA) devices is characterized by observational studies that report pre-hearing and post-hearing outcomes in patients treated with BAHA. Many of these studies combine patients with differing underlying disease states and indications. No randomized controlled trials (RCTs) have compared implantable bone-conduction hearing aids to other hearing augmentation devices, or sham devices. Following is a summary of key findings.
Bone-Anchored Hearing Aids
Overall Efficacy of Bone-Anchored Hearing Aids
Systematic Reviews and Meta-Analysis
A systematic review by the Health Technology Assessment Program was published in 2011 on the use of BAHAs for bilateral hearing impairment. (1, 2) The authors noted that the quality of available studies on the use of BAHAs is weak. No studies with control groups were identified for the review. Cohort pre-post studies and cross-sectional comparative studies demonstrate improvements in hearing with use of BAHAs over conventional bone-conduction hearing aids or unaided hearing. However, whether improvements in hearing with BAHAs are greater than air-conduction hearing aids is uncertain. Additionally, bilateral use of BAHAs improved hearing outcomes in some patients over unilateral use, but the evidence was uncertain. Implant loss was noted to be between 6.1% and 19.4%. The authors noted hearing-specific quality of life improved, but overall quality of life did not differ.
Since the publication of the Health Technology Assessment Program systematic review, a number of observational studies have evaluated specific aspects of BAHA implantation or reported outcomes in specific populations. Several observational studies have suggested that newer-generation BAHAs with fully digital signal processors improve hearing to a greater degree than earlier-generation devices. (3,4)
In 2014, Farnoush et al. retrospectively compared BAHA placement with reconstruction of the external auditory canal for children and adolescents with congenital aural atresia or stenosis who were treated at a single institution from 1988 to 2011. (5) Sixty-eight patients were included, 49 who underwent external auditory canal reconstruction (EACR) and 19 who received a BAHA. Groups differed significantly in terms of age, presence of bilateral atresia, and presence of an associated syndrome. Audiologic data were available for 41 patients. At short-term (<6 months post-surgery) follow up, the BAHA group had larger hearing gains on air conduction than the EACR group (44.3 dB vs 20.0 dB; P<0.001); similarly, the BAHA group had larger hearing gains at long term (>1 year post-surgery) follow up (44.5 dB vs 15.3 dB; P<0.001). Quality of life scores and requirements for revision surgery did not differ significantly between the groups.
In 2010, Ramakrishnan and colleagues retrospectively reviewed bone-anchored and Softband-held conductive hearing aids in 109 children and young adults in a single center. (6) The patient population was somewhat unique in that many patients had craniofacial or genetic syndromes in addition to hearing loss (22 of 109). Criteria for the selection of the implanted device or the Softband were not described; however, the authors did note an uneven distribution by mean age, gender, and syndromic co-morbidity. Primary measures were the Glasgow Benefit Inventory or Listening Situation Questionnaire (parent version) administered at least 3 months following hearing aid intervention. Mean overall Glasgow Benefit Inventory scores were reported as +29 (range +11 to +72). The mean Listening Situation Questionnaire score of 17 was reported as less than a referral cutoff of 22. The authors conclude that this population benefits from bone-anchored and Softband-held conductive hearing aids based on mean scores. However, the study is limited due to a hetereogeneous patient population, a lack of pre-intervention measures, or a controlled comparator group.
In 2004, McLarnon and colleagues reported outcomes (benefits) for BAHAs by patient subgroups based on 69 of 94 (73%) patients who completed a questionnaire. (7) This study noted the greatest benefit in those with congenital ear disorders. It also showed benefit to restoring stereo hearing to patients with an acquired unilateral hearing loss after acoustic neuroma surgery.
In 2008, Tringali and colleagues surveyed patients using a BAHA to compare patient satisfaction by indication: 52 respondents with conductive or mixed hearing loss (44 with chronic otitis and 8 with malformation of the middle ear) compared with 118 with single-sided deafness (SSD) (2 after surgery for meningioma, idiopathic sudden deafness, and sensorineural hearing loss complicating surgery of the middle ear). (8) Levels of satisfaction and quality of life were significantly poorer in the SSD than in the conductive hearing loss (CHL) group, although generally good with the exception of sound localization.
Earlier case studies suggested that the BAHA was associated with improved hearing compared with earlier generations of bone-conduction devices and air-conduction hearing aid, (9,10) and produce acceptable hearing outcomes in individuals unable to receive an air-conduction hearing aid. (11,12)
Efficacy of Bilateral BAHA Devices in Conductive or Mixed Hearing Loss
Use of bilateral devices has been evaluated in patients with conductive or mixed hearing losses. A number of studies, published over several years, have demonstrated a consistent improvement in speech recognition in noise and in sound localization with bilateral devices
Janssen et al. (2012) conducted a systematic review to assess the outcomes of bilateral versus unilateral BAHA for individuals with bilateral permanent conductive hearing loss (CHL). (13) Their search strategy included studies of all languages published between 1977 and July 2011. Studies were included if subjects of any age had permanent bilateral CHL and bilateral implanted BAHAs. Outcome measures of interest were any subjective or objective audiologic measures, quality of life indicators, or reports of adverse events. Eleven studies met their inclusion criteria. All 11 studies were observational. There were a total of 168 patients in the 11 studies, 155 of whom had BAHAs and 146 of whom had bilateral BAHAs. In most studies, comparisons between unilateral and bilateral BAHA were intra-subject. Patients ranged from 5 to 83 years of age; 46% were male, and 54% were female. Heterogeneity of the methodologies between studies precluded meta-analysis, therefore a qualitative review was performed. Results from 3 of 11 studies were excluded from synthesis because their patients had been included in multiple publications. Adverse events were not an outcome measure of any of the included studies. (13) In general, bilateral BAHA was observed to provide additional objective and subjective benefit compared to unilateral BAHA. For example, the improvement in tone thresholds associated with bilateral BAHA® ranged from 2-15dB, the improvement in speech recognition patterns ranged from 4-5.4dB, and the improvement in the Word Recognition Score ranged from 1-8%. However, these results were based on a limited number of small observational studies consisting of heterogeneous patient groups that varied in age, severity of hearing loss, etiology of hearing loss, and previous amplification experience. (13)
Examples of individual studies include the following. In 2001, Bosman and others reported on findings from 25 patients who were using bilateral devices. (14) They found that both speech recognition in noise and directional hearing improved with the second device. In a 2004 publication, Priwin and colleagues reported similar findings in 12 patients with bilateral devices. (15) A consensus statement published in 2005 concluded that bilateral devices resulted in binaural hearing with improved directional hearing and improved speech-in-noise scores in those with bilateral conductive hearing loss and symmetric bone-conduction thresholds. (16) A number of additional studies that are cited in this report found benefits similar to those noted in the studies of the Bosman et al. and Priwin et al. reports. (14, 15) Positive outcomes continue to be reported: Dun et al (2010) (17) identified improvements in the Glasgow Benefit Inventory in children (n=23), while Ho et al (18) reported the same benefit in adults (n=93). Thus, based on these numerous studies, bilateral devices may be considered medically necessary when there is bilateral conductive or mixed hearing loss with symmetric bone-conduction thresholds.
Efficacy of BAHA Devices for Unilateral Sensorineural Hearing Loss
Several centers have reported on findings from observational studies designed to evaluate the benefits of BAHA for patients with unilateral sensorineural hearing loss, or single-sided deafness (SSD). Most of these studies have been retrospective. In 2014, Peters et al reported results from a systematic review of the use of BAHA devices with contralateral routing of sound systems for SSD. (19) The authors included 6 studies that met eligibility criteria, 5 of which were considered to have moderate to high directness of evidence and low to moderate risk of bias. The 5 studies evaluated included a total of 91 patients and were noted to have significant heterogeneity in the populations included. For speech perception in noise, there was not consistent improvement with aided hearing over unaided hearing in all environments. All studies reported equal sound localization in the aided and unaided conditions, and quality of life measures were similar for the aided and unaided conditions.
In one prospective study conducted within a hospital auditory implant center in the United Kingdom, Pai and colleagues reported significant improvement in the average score in all three sections (speech hearing, spatial hearing, other qualities) of the SSQ questionnaire following a BAHA implant in 25 adult patients. (20)
Zeitler et al. reported on a retrospective case series of 180 patients undergoing unilateral or bilateral BAHA for single-sided deafness with residual hearing in the implanted ear within a university medical center in the United States. (21) Significant improvement was reported in objective hearing measures (speech-in-noise and monosyllabic word tests) following BAHA® implantation. Subjective benefits from BAHA® varied across patients according to results from the Glasgow Hearing Aid Benefit Profile but patients with residual hearing in the affected ear tended toward improved satisfaction with their device postoperatively. (21) Nicolas et al (2013) undertook a retrospective review of 36 patients implanted with a BAHA® within a university medical center in France. (22) Their results showed an improvement in speech perception in noise with the BAHA®, but no improvement in sound localization based on a 2-year follow-up period. (22)
Baguley et al. (2006) reviewed the evidence for contralateral BAHAs® in adults with acquired unilateral sensorineural hearing loss. (23) None of the four controlled trials reviewed showed a significant improvement in auditory localization with the bone-anchored device. However, speech discrimination in noise and subjective measures improved with these devices; for these parameters, the BAHAs resulted in greater improvement than that obtained with the conventional air-conduction contralateral routing of signal (CROS) systems. The authors of this review did note shortfalls in the studies reviewed.
Lin et al. (2006) reported on use of the BAHAs in 23 patients with unilateral deafness, and noted that speech recognition in noise was significantly better with the BAHA® device than with the air-conduction CROS device. (24) While the report also comments that benefit was seen in those with moderate sensorineural hearing loss in the contralateral ear (25–50 dB), this conclusion was based on five patients. Larger studies are needed to support the use of BAHA for bilateral sensorineural hearing loss.
Two studies of BAHAs® for congenital unilateral conductive hearing impairment are reported by Kunst et al. In a 2008 study, aided and unaided hearing was assessed in 20 patients using sound localization and speech recognition-in-noise tests. (25) Many patients showed unexpectedly good unaided performance, however non-significant improvements were observed in favor of the BAHA. Six of 18 patients with a complete data set did not show any improvement at all; however compliance with BAHA use in this patient group was remarkably high suggesting patient benefit. The same authors evaluated 10 adults and 10 children using 2 disability-specific questionnaires and found an overall preference for the BAHA over unaided hearing in several specific hearing situations. (26) Improvement on the Glasgow children’s benefit inventory was most prominent in the learning domain. The 10 adults showed an already good score on the Speech, Spatial and Qualities of hearing scale in the unaided situation.
In 2010, Gluth et al. reported on 21 patients with profound unilateral sensorineural hearing loss followed for an average of 3.2 years after BAHA implantation. (27) Perceived benefits and satisfaction were reported to improve significantly in BAHA® users, and 81% continued using the device long term. However, severe local skin reactions were frequently experienced (38% Grade 2 and above).
Efficacy of BAHA Devices in Children Younger than Five Years of Age
A 2008 review article notes that for children younger than 5 years, other solutions (such as a bone conductor with transcutaneous coupling) should be utilized. (28) This recommendation is in agreement with the U.S. Food and Drug Administration (FDA) clearance of the osseointegration implant only for children 5 years of age and older, and adults. This is reflected in the policy statements.
The BAHA device has been investigated in children younger than 5 years in Europe and the United Kingdom. A number of reports describe experience with preschool children or children with developmental issues that might interfere with maintenance of the device and skin integrity. A 2-stage procedure is used in young children. In the first stage, the fixture is placed into the bone and allowed to fully develop osseointegration. After 3-6 months, a second procedure is performed to connect the abutment through the skin to the fixture. (29)
Marsella et al. (2012) have reported on their center’s experience in Italy with pediatric BAHA from the inception of their program in 1995 to December 2009. (30) A total of 47 children (21 females and 26 males) were implanted, seven of these were younger than 5 years. The functional gain was significantly better with BAHA than conventional bone-conduction hearing aids and there was no significant difference in terms of functional outcome between the seven patients receiving a BAHA at an age younger than five years and the rest of the patient cohort. Based on these findings, the study authors suggest that implantation of children at an age younger than five years can be conducted safely and effectively in such settings. (30) The conclusions are limited by the small number of children less than 5 years of age in the study and the limited power to detect a difference between younger and older children.
Davids et al. (2007) at the University of Toronto provided BAHA devices to children less than 5 years of age for auditory and speech-language development and retrospectively compared surgical outcomes for a study group of 20 children 5 years or younger and a control group of 20 older children. (31) Children with cortical bone thickness greater than 4 mm underwent a single-stage procedure. The interstage interval for children having 2-stage procedures was significantly longer in the study group in order to allow implantation in younger patients without increasing surgical or postoperative morbidity. Two traumatic fractures occurred in the study group versus 4 in the older children. Three younger children required skin site revision. All children were wearing their BAHA® devices at time of writing. McDermott et al. reported on the role of bone anchored hearing aids in children with Down syndrome in a retrospective case analysis and postal survey of complication rates and quality of life outcomes for 15 children aged 2 to 15 years. (32) All patients were using their BAHA® devices after follow-up of 14 months. No fixtures were lost; skin problems were encountered in 3 patients. All 15 patients had improved social and physical functioning attributed to improved hearing.
Safety and Adverse Events Related to Bone-Anchored Hearing Aids
In addition to the literature evaluating the effectiveness of BAHA devices in improving hearing, a number of studies have evaluated or reported specifically on complications related to BAHAs.
In 2013, Kiringoda et al. reported on a meta-analysis of complications related to BAHA implants. Included in the meta-analysis were 20 studies that evaluated complication in 2134 adult and pediatric patients who received a total of 2310 BAHA implants. (33) While the quality of available studies was considered poor and lacking in uniformity, complications related to BAHA implants were mostly minor skin reactions. The incidence of Holgers grade 2 to 4 skin reactions was 2.4% to 38.1% in all studies (grade 2, red and moist tissue; grade 3, granulation tissue; and grade 4, infection leading to removal of the abutment). The incidence of failed osseointegration was 0% to 18% in adult and mixed population studies and 0% to 14.3% in pediatric population studies. The incidence of revision surgery was 1.7% to 34.5% in adult and mixed population studies and 0.0% to 44.4% in pediatric population studies. Implant loss occurred in 1.6% to 17.4% in adult and mixed population studies and in 0.0% to 25% in pediatric studies.
In 2012, Dun et al. assessed soft tissue reactions and implant stability of 1,132 percutaneous titanium implants for bone conduction devices through a retrospective survey of 970 patients undergoing implants between September 1988 and December 2007 at the University Medical Center in the Netherlands. (34) The study investigators also examined device usage and comparisons between different patient age groups (children, adults, and the elderly) over a five-year follow-up period. Implant loss was 8.3%. In close to 96% of cases, there were no adverse soft tissue reactions. Significantly more soft tissue reactions and implant failures were observed in children compared with adults and the elderly (p < 0.05). Implant survival was lower in patients with mental retardation compared with patients without mental retardation (p = 0.001). (34)
In 2010, Hobson et al. reviewed complications on 602 patients at a tertiary referral center over 24 years and compared their observed rates to those published in 16 previous studies. (35) The overall observed complication rate of 23.9 % (144 of 602) is similar to other published studies (complication rate 24.9% + 14.85). The most common complications were soft tissue overgrowth, skin infection, and fixture dislodgement. The observed rate of revision surgery of 12.1% (73 of 602) was also similar to previously published rates of 12.7%. Top reasons for revision surgery were identical to observed complications. In 2011, Wallberg et al. reported on the status of 150 implants placed between 1977 and 1986 and followed for a mean of 9 years. (36) Implants were lost in a total of 41 patients (27%). The reasons for implant loss were: removal in 16 patients, osseointegration failure in 17 patients, and direct trauma in 8 patients. In the remainder of 132 patients with implant survival, BAHAs were still being used by 119 patients (90%) at the end of follow-up. For children, implant complications were even more frequent, as reported by Kraai et al. in a follow-up evaluation of 27 implants placed in children ages 16 years or younger between 2002 and 2009. (37) In this retrospective report, soft tissue reactions occurred in 24 patients (89%); removal of the implant or revision surgery was required in 10 patients (37%); 24 patients (89%) experienced soft tissue overgrowth and infection; and 7 patients experienced implant trauma. Chronic infection and overgrowth at the abutment prevented use of the implant in 3 patients (11%).
In 2014, Allis et al. conducted a prospective observational cohort study with a retrospective historical control to evaluate complication rates of skin overgrowth, infection, and the need for revision surgery associated with a BAHA implant with a longer (8.5 mm) abutment. (38) Twenty-one subjects were treated with the 8.5 mm abutment implant from 2011 to 2012 and were compared with 23 subjects treated with a 5.5 mm-abutment implant from 2010 to 2011. Groups were generally similar at baseline, with the exception that the 8.5 mm abutment implant patients were older (62 years vs 48 years, P=0.012). Patients in the longer abutment group were less likely to experience infection (10% vs 43%; P=0.02), skin overgrowth (5% vs 41%; P=0.007), and need for revision (10% vs 45%; p=0.012).
Also in 2014, Calvo Bodnia et al. reported results from a retrospective cohort study of patients implanted with a BAHA implant at a single center from 2004 to 2012, with a focus on implant loss, adverse skin reactions, skin overgrowth, and discomfort leading to device removal. (39) The authors reviewed 185 implantations in 176 patients. Ten patients were younger than 16 years (11 implantations), 117 were between 17 to 64 years (121 implantations), and 49 patients were between 65 and 86 years (53 implantations). Adverse skin reactions occurred in 14% of patients, and spontaneous implant loss occurred in 3.8%, at a mean of 2.5 years. The abutment was removed because of discomfort and/or no benefit in 10% overall.
In another retrospective cohort study, Rebol reported skin/soft tissue reactions for 47 patients implanted with BAHA devices. (40) Over 9 years of follow up, the percentage of patients with skin inflammation of 2 or greater on Holger’s skin inflammation grading system ranged from 6% to 22%. Three patients with grade 4 inflammation required fitting of a longer abutment due to skin thickening.
In a large retrospective cohort study of 763 BAHA implants in 571 patients treated at a single institution from 1977 to 2011, Larsson et al. (2014) reported on rates of implant loss and removal. (41) A total of 141 implants (18%) were lost over a mean follow up of 6.6 years, 109 (14%) due to loss of osseointegration and 21 (3%) due to trauma, with 11 elective removals.
Different techniques for surgically implanting BAHA devices and specific BAHA designs are under investigation to yield improved safety outcomes. Fontaine et al. (2014) compared complication rates after 2 different surgical techniques for BAHA implantation among 32 patients treated from 2004 to 2011. (42) Complications requiring surgical revision occurred in 20% of cases who underwent a skin flap implantation method (N=20) and in 38% of cases who underwent a full-thickness skin graft implantation method (N=21; P=0.31). Hultcrantz et al (2014) reported shorter surgical times and fewer cases of numbness and peri-implant infections in 12 patients treated with a non-skin-thinning technique, compared with 24 patients treated with either a flap or dermatome implantation technique. (43) In a comparison of 2 types of BAHA devices, one with a 4.5 mm diameter implant with a rounded 6 mm abutment (N=25) and one with a 3.75 mm diameter implant with a conically-shaped 5.5 mm abutment (N=52), Nelissen et al (2014) reported that implant survival was high for both groups over 3 years of follow up, although the conically-shaped abutment had greater stability. (44) Singham et al (2014) reported results of a BAHA implantation technique without soft tissue reduction in conjunction with a longer device abutment in 30 patients. (45) While 25 patients had no post-operative complications, 3 developed pain requiring soft-tissue reduction
Partially Implantable Magnetic Bone-Conduction Hearing Aids
In 2011, Seigert reported on the use of a partially implantable bone conduction hearing system (Otomag®) that uses magnetic coupling for acoustic transmission. (46) This hearing system is reported to have been implanted in more than 100 patients followed in the past 5 years, but results are only presented on 12 patients. Since the acoustics must pass through the skin rather than by direct bone stimulation through an abutment on the BAHA-type implants, Seigert reports sound attenuation is reduced by less than 10 dB. The preliminary results of the partially implantable hearing system in 8 unilaterally and 4 bilaterally implanted patients showed average hearing gains of 31.2 ± 8.1 dB in free field pure tone audiogram. The free field suprathreshold speech perception at 65 dB increased from 12.9% preimplantation to 72.1% postimplantation.
In 2013 Hol et al. reported on a comparison of BAHA percutaneous implants to partially implantable magnetic
transcutaneous bone-conduction hearing implants using the Otomag® Sophono device in 12 pediatric patients, ranging in age from 5 to 12 years, with congenital unilateral CHL. (47) Sound field thresholds, speech recognition threshold and speech comprehension at 65 dB were somewhat better in patients with the BAHA implant (n=6) than the partially implantable hearing implant (n=6). Using a skull simulator, output was 10 to 15 dB lower with the partially implantable device than the BAHA device.
O’Niel et al. (2014) reported outcomes for 10 pediatric patients with conductive hearing loss treated with the Otomag Sophono device at a single center. (48) A total of 14 ears were implanted with no surgical complications. The skin complication rate was 35.7%, including skin breakdown (n=2) and pain and erythema (n=5); negative outcomes resulted in 5 (36%) of 14 ears having significant enough difficulties to discontinue use for a period. The mean aided pure-tone average was 20.2 dB hearing level, with a mean functional gain of 39.9 dB hearing level. Patients without skin complications consistently used their devices, with an average daily use of 8 to 10 hours.
Centric et al. (2014) also reported outcomes for 5 pediatric patients treated with the Otomag Sophono device at a single center. (49) Etiologies of hearing loss were heterogeneous and included bilateral moderate or severe conductive hearing loss and unilateral sensorineural hearing loss. The average improvement in pure-tone average was 32 dB hearing level and the average improvement in speech response threshold was 28 dB hearing level. All patients were responding in the normal to mild hearing loss range in the operated ear after device activation.
In a similar study, Marsella et al. (2014) reported outcomes for 6 pediatric patients treated with the Otomag Sophono device at a single center. (50) All subjects had bilateral conductive or mixed hearing loss, and 3 had associated syndromes. Patients ranged in age from 5 to 17 years. Post-operatively, one patient experienced ulceration of the skin under the magnet, which was successfully treated, and one patient experienced pain associated with the device leading to discontinuation of device use. The median improvement in pure-tone average was 33 dB hearing level and the median free-field pure tone average (0.5-3 kHz) with the device was 32.5 dB hearing level.
In addition to studies of currently FDA-approved partially-implantable bone-conduction devices, a number of case series were identified which evaluate the Bonebridge implant, which is not currently cleared for marketing in the US. (51-55)
Non-implanted BAHA with Softband
In 2010, Christensen et al. reported on a retrospective five-year case review of ten children, with ages ranging from 6 months to 16 years of age, with bilateral conductive hearing loss due to congenital aural atresia (CAA) and/or microtia. The case-review study participants initially trialed the use of traditional bone-conduction hearing aids, then proceeded to the externally worn BAHA® with Softband™, and eventually to a unilateral implanted BAHA®. The devices were assessed for functional gain and hearing threshold measures at 500, 1000, 2000, and 4000 Hz frequencies. The findings of the report showed a statistically significant improvement when using the externally worn BAHA® with Softband™ over traditional bone-conduction hearing aids. (56)
Ongoing and Unpublished Clinical Trials
A search of online site ClinicalTrials.gov at the time of the 2015 policy review found the following studies.
Studies for bone-conduction hearing implant devices
Studies for partially implantable transcutaneous BAHA
Summary of Evidence
The available evidence for unilateral or bilateral implantable bone-conduction (bone-anchored) hearing aid(s) consists of observational studies that report pre- post differences in hearing parameters after treatment with BAHA. While this evidence is not idea, it is sufficient to demonstrate improved net health outcome for patients 5 years of age or older in certain situations. The evidence supports the use of these devices in patients with conductive or mixed hearing loss who meet other medical and audiologic criteria. For patients with single-sided sensorineural deafness, a binaural hearing benefit may be provided by way of contralateral routing of signals to the hearing ear. There is evidence that bilateral devices improve hearing to a greater degree than do unilateral devices. Bone-anchored hearing aids may be considered as an alternative to air-conduction devices in these patients. Due to the lack of both high-quality evidence and FDA approval, other uses of implanted bone-conduction (bone-anchored) hearing aids, including use in children younger than 5 years and patients with bilateral sensorineural hearing loss, BAHA are unproven. In hearing impaired children younger than 5 years of age, to facilitate early speech and language development, the use of a BAHA® with a headband or softband as a presurgical trial may be warranted based on a review of the medical records.
The available evidence for partially implantable bone-conduction hearing systems is preliminary and limited to small, single-center case studies. Therefore, conclusions on net health outcomes cannot be made, and partially implantable bone-conduction hearing systems are considered investigational.
Practice Guidelines and Position Statements
American Academy of Otolaryngology-Head and Neck Surgery
The American Academy of Otolaryngology-Head and Neck Surgery has a position statement on the use of implantable hearing devices that was revised in 2013 and states that the Academy “considers the implantation of a percutaneous or transcutaneous bone conduction hearing device, placement of a bone conduction oral appliance, and implantation of a semi-implantable hearing device or totally implantable hearing device to be acceptable procedures for the relief of hearing impairment when performed by, or in collaboration with, a qualified otolaryngologist-head and neck surgeon.” (57)
U.S. Preventive Services Task Force Recommendations
Medicare National Coverage
The Medicare Benefit Policy Manual provides detailed information about Medicare coverage, benefits and exclusions related to osseointegrated implants as prosthetic devices .(58, 59)
Implantation or replacement of electromagnetic bone conduction hearing device in temporal bone
Removal or repair of electromagnetic bone conduction hearing in temporal bone
Implantation, osseointegrated implant, temporal bone, with percutaneous attachment to external speech processor/cochlear stimulator; without mastoidectomy
Replacement (including removal of existing device), osseointegrated implant, temporal bone, with percutaneous attachment to external speech processor/cochlear stimulator; without mastoidectomy
Auditory osseointegrated device, includes all internal and external components
Auditory osseointegrated device, external sound processor, replacement
Auditory osseointegrated device, external sound processor, used without osseointegration, body worn, includes headband or other means of external attachment
External recharging system for battery (external) for use with implantable neurostimulator
Type of Service
Place of Service
Figure 1 source: http://emedicine.medscape.com/article/1989565-overview#showall
Figure 2 source:
New policy. Policy includes statement about medical necessity criteria for use of BAHA with headband or softband for children less than 5 years of age; that was not addressed in the BC policy. A table of frequency of BAHA replacement parts is included in the benefit application section. This policy replaces 7.01.03.
Replace policy. Updated with literature review and references renumbered. Policy statements unchanged.
Replace policy. Added “magnetic” and “BAHA Attract” to last investigational policy statement. Clarified Benefit Application statement. Rationale updated with literature review through February 2014. Simplified Medicare National Coverage statement. References 3, 25, 34 added; others renumbered/removed. In appendix, revised figures 1-2, added source hyperlinks. Policy statement changed as noted. ICD-9 and ICD-10 codes removed from the policy; these are not utilized in adjudication and were informational only.
Annual Review. Policy updated with literature review through January, 2015. References 3-5, 19, 36-43, 46-55, 57, 59 added. Rationale section reorganized. Policy statements unchanged.
Disclaimer: This medical policy is a guide in evaluating the medical necessity of a particular service or treatment. The Company adopts policies after careful review of published peer-reviewed scientific literature, national guidelines and local standards of practice. Since medical technology is constantly changing, the Company reserves the right to review and update policies as appropriate. Member contracts differ in their benefits. Always consult the member benefit booklet or contact a member service representative to determine coverage for a specific medical service or supply. CPT codes, descriptions and materials are copyrighted by the American Medical Association (AMA).