Percutaneous Bone-anchored Hearing Aid Research Articles

The effect of percutaneous and transcutaneous BAHA on hearing and subjective auditory abilities: A comparative study.

Hearing loss significantly affects communication, social interactions, and the overall quality of life. The bone-anchored hearing aid (BAHA) is an implantable system that bypasses the outer and middle ear to directly stimulate the cochlea through bone conduction. This study aimed to compare hearing performance and subjective auditory ability improvements between transcutaneous and percutaneous BAHA devices using audiological assessments and Speech, Spatial and Qualities of Hearing Scale. This cross-sectional prospective study included 29 participants aged 14 to 69 years who had used BAHA for at least 6 months. Both Cochlear Baha System's percutaneous (connect) and transcutaneous (attract) implants were evaluated. Audiological assessments involved pure-tone audiometry, speech recognition threshold, and free-field (FF) audiometry, while subjective auditory ability was measured using the Turkish Speech, Spatial and Qualities of Hearing scale (Tr-SSQ). Significant improvements in FF audiometry averages and speech recognition thresholds were observed with BAHA compared to without BAHA (P < .001). Both implant types provided similar FF averages, speech audiometry results, and Tr-SSQ outcomes, with no significant differences between them. Tr-SSQ scores showed substantial satisfaction, indicating significant improvements in speech perception, spatial perception, and hearing quality with BAHA (P < .001). The findings align with previous research, demonstrating that BAHA is a reliable and effective solution for hearing rehabilitation. The study also emphasized the importance of using both audiological test results and daily hearing function scales to comprehensively evaluate the benefits of hearing rehabilitation in real-world environments. In conclusion, BAHA, regardless of the implant type, can provide predictable and lasting improvements in hearing thresholds and daily hearing abilities, making it a valuable option for patients with conductive hearing loss.

Reabilitação auditiva com sistemas Baha® transcutâneo e percutâneo

ABSTRACT Purpose Longitudinally verify the influence of auditory tonal thresholds obtained with transcutaneous and percutaneous bone-anchored hearing aids on speech perception in individuals with external and/or middle ear malformation and chronic otitis media. Methods Observational, retrospective, longitudinal follow-up study of 30 unilateral users of the transcutaneous and percutaneous Baha® system for the collection of secondary data on pure tone thresholds obtained through free field audiometry and sentence recognition threshold in silence and noise in conditions: without the prosthesis; at the time of activation; in the first month of use (post 1); and in the third month (post 2). Results There was a significant difference between pure tone thresholds obtained at frequencies of 3 and 4kHz with better results for the percutaneous technique at all evaluation moments. For both systems, better performance was observed in sentence recognition in silence and in noise, with a significant difference in activation (p&lt;0.001), but it remained stable during the other evaluation moments. The percutaneous system showed better benefit in recognizing sentences in noise only on activation (p=0.036), when compared to the transcutaneous system. Conclusion The percutaneous system provided better audibility for high frequencies; however, such audibility did not influence sentence recognition in the silent situation for both systems. For the noise situation, better responses were observed in the percutaneous system, however, the difference was not maintained over time.

Transcutaneous versus percutaneous bone-anchored hearing aids: A quality of life comparison

PurposeTo determine whether patients have improved quality of life outcomes with percutaneous bone conduction implant (p-BCI) versus transcutaneous bone conduction implant (t-BCI). Materials & methodsRetrospective chart review of patients who have undergone placement of a BCI in the Ascension St John Providence Health System from 2013 to 2018. Patient satisfaction of t-BCI and p-BCI was measured using a questionnaire that incorporated the Glasgow Benefit Inventory (GBI) and BAHA, aesthetic, hygiene & use (BAHU) survey. Key outcome variables were separated into 2 categories: (1) evaluation of wound healing and implant-associated complications, and (2) quality of life improvements. ResultsComparative analysis of the 27 p-BCI patients and 10 t-BCI patients showed overall positive benefit with no statistically significant difference on quality of life improvement between the two groups. Total complication rates for p-BCI (48.1 %) vs t-BCI (10 %) was marginally significant (p = 0.056). Rate of revision for p-BCI versus t-BCI was 14.8 % vs 0 %, respectively. ConclusionThis study provides a much-needed comparative insight in patient's experience with these two devices. Understanding which device is preferable in the patient's view will offer helpful information for guiding proper implant selection.

Functional and patient-reported outcomes of bone-anchored hearing aids (BAHA): A prospective case series study

ObjectiveThe purpose of this study was to evaluate the functional and patient-reported outcomes, and their correlation, after percutaneous bone-anchored hearing aid (BAHA) implantation. MethodsA prospective study was conducted between January 2018 and December 2020 in a tertiary care center. All adult patients who were implanted with a percutaneous BAHA device during this evaluation period were included in the study. Complete auditory function and patients reported outcome measures (PROMs) were assessed in the preoperative period and 6 months after the implant activation. The PROMs included a generic form (Medical Outcome Study 36 Short Form Healthy Survey (MOS SF-36)), and three disease-specific forms (Hearing Handicap Inventory (HHI), Satisfaction with Amplification in Daily Life Scale (SADLS), and Tinnitus Handicap Inventory (THI)). ResultsTwenty-two patients with an average age of 53 years were included in the study. The overall functional gain with the BAHA in sound-field pure tone average (PTA) was 29 dB, with no statistically significant differences according to surgical indication (F(3,18) = 2.319, p = 0.110). The greater the preoperative air-bone gap, the greater the functional gain obtained (r = 0.505, p < 0.05). In the PROMs, we found a significant improvement in HHI scores (p < 0.005) and a significant increase in overall SADLS scores (p < 0.05) with the use of percutaneous BAHA devices. We did not verify any statistically significant correlation between functional and PROMs results. ConclusionsThe BAHA is a safe and effective alternative hearing rehabilitation option in selected patients. The PROMs results prove patient's overall satisfaction.

Surgical Solution for the Transformation of the Percutaneous Bone Anchored Hearing Aid to a Transcutaneous System in Complicated Cases.

Bone-anchored hearing aids (BAHAs) have been used for multiple types of hearing loss both in pediatric and adult cases. In the last decades, the percutaneous BAHA® Connect System (Cochlear Ltd., Sydney, Australia) was replaced by the fully implanted transcutaneous, magnet-based BAHA® Attract System (Cochlear Ltd., Sydney, Australia). Since the implantable part of the Attract device is fully covered with soft tissue, skin complications that were frequently observed in the percutaneous system, could be eliminated. As an outcome of this important advantage of the Attract System, conversion of the percutaneous into a transcutaneous system should be considered. In the following methodology report, a possible surgical technique is described. The method can easily be adopted to different conditions in which the replacement of the percutaneous device is necessary.

Resultados audiológicos y de calidad de vida en pacientes con transición del sistema Baha Connect® a Baha Attract®

Introducción: los implantes auditivos de conducción ósea percutáneos han sido usados de forma exitosa. Sin embargo, un número importante de pacientes reportan reacciones en piel repetitivas. Los implantes auditivos transcutáneos son una alternativa que pueden solventar estas complicaciones. Con este estudio queremos describir los resultados audiológicos y de calidad de vida en pacientes que requirieron transición del sistema percutáneo a transcutáneo.Metodología: estudio observacional descriptivo, se incluyeron pacientes con implante auditivo percutáneo que requirieron transición a sistema transcutáneo. Se evaluó el desempeño auditivo utilizando una prueba con fondo ruidoso y se aplicó la escala de calidad de vida “Glasgow Benefit Inventory”-GBI.

Long-term soft tissue outcomes for hydroxyapatite-coated bone-anchored hearing implant surgery.

To investigate skin-related postoperative outcomes following a tissue preservation technique in percutaneous hydroxyapatite-coated bone-anchored hearing aid (BAHA) abutment implantation. A retrospective medical records review of adult patients, who underwent single-stage BAHA implantation between July 2013 and November 2017 at a tertiary centre was conducted. Surgical procedures were performed by a single surgeon using a linear incision soft tissue preservation technique. Patients were reviewed at 1week, 4weeks, 3months, 6months, and annually postoperatively and soft tissue reactions were graded using Holger's score RESULTS: There were 102 patients included with a slight female preponderance (female:male 56:46). There were 586 follow-up episodes during the study period. From the recorded follow-up episodes, Holger's scores were documented as follows: Holger score 0 (89%); 1 (7%); 2 (2%); 3 (1.9%). Three patients (3%) required peri-abutment soft tissue excision (Holger 3) and insertion of longer abutments. One patient (1%) reported atraumatic implant loss. The BAHA was re-implanted in two patients (2%) due to traumatic dislodgement. There was a statistically significant association (p = 0.009) when the mean time to minor skin complications was compared with mean time to a significant skin reaction. Tissue preservation technique is the procedure of choice for BAHA abutment implant surgery. It confers excellent soft tissue outcomes and an excellent implant survival rate.

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

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

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.

Pediatric unilateral sensorineural hearing loss: implications and management.

The purpose of this review is to summarize current studies detailing the impact of unilateral sensorineural hearing loss in children and the most current modalities of treatment used in its management. Current studies corroborate historic views on the impact of unilateral sensorineural hearing loss on patient wellbeing and academic success and stress the use of additional surveillance and studies to diagnose those patients that may pass standard screening practices and suffer from lack of prompt and proper care. With respect to management, notable findings include the continuous development of improved conventional and contralateral routing of signal amplification devices that may act to provide alternatives to percutaneous bone-anchored hearing aid implantation. These include improvements in more conventional hearing aid technology, so as to bridge the performance gap with the classical bone-anchored hearing aid implant, and the development of partially implanted transcutaneous bone conduction hearing devices. Due to dissatisfaction with sound localization, a new and significant development is the burgeoning accumulation of research on cochlear implantation for the treatment of unilateral sensorineural hearing loss in children. With advances in technology in historic modalities of treatment, and the advent of new modalities such as cochlear implantation, the clinician has a wide armamentarium by which to provide treatment to patients based on clinical circumstances and patient desires.

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

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

Retrieved bone-anchored percutaneous amputation prosthesis showing maintained osseointegration after 11 years—a case report

The patient is a woman born in 1960. She suffered a high transfemoral amputation due to a tumor in 1976. In 1993, she was enrolled for treatment with a custom-designed bone-anchored implant solution. The surgery was performed in 2 stages, Briefly, at stage 1 of surgery (S1), a titanium fixture was implanted in residual femoral bone after reaming of the intramedullary canal, and using a 3-D centering guide and fluoroscopy to ensure proper positioning. At stage 2 of surgery (S2) 6 months later, a full skin thickness flap was trimmed of subcutaneous fat and sutured to the distal end of the femoral bone, essentially according to the surgical technique developed for percutaneous bone-anchored hearing aids (Tjellstrom 1989). In conjunction with S2, a skin-penetrating abutment was inserted into the fixture and secured via an abutment screw. Following S2, the rehabilitation included a gradual increase of the load on the implant, the fitting of an external prosthesis to the abutment, increased activity, and prosthetic use. In 1998, the titanium fixture fractured at the distal end, and a custom-made abutment was installed to try to avoid fixture removal. This abutment failed in 2000, and was exchanged. In 2004, the fixture fractured again due to fatigue, and it was removed. The distal part was loose and was easily removed, while the proximal part was drilled out with a trephine burr together with a surrounding tissue collar. The fixture with surrounding bone was immersed in 4% formalin. The patient was successfully revised with a new implant and has not suffered from any new fracture. Specimen preparation The specimen was dehydrated and embedded in LR White (London Resin Co. Ltd., UK) and divided into 2 pieces through the long axis by use of a diamond band saw. One part was used for preparation of a toluidine blue stained ground section for histological and histomorphometrical analysis using light microscopy. The counter part of the block was divided further into one smaller part at the apical end, containing 7 threads intended for micro-CT analysis in a Skyscan 1172. The rest was polished with grit paper to create an even surface, and then sputter-coated with gold (approximately 10 nm) and analyzed by scanning electron microscopy (SEM).

Analysis and Design of RF Power and Data Link Using Amplitude Modulation of Class-E for a Novel Bone Conduction Implant

This paper presents analysis and design of a radio frequency power and data link for a novel Bone Conduction Implant (BCI) system. Patients with conductive and mixed hearing loss and single-sided deafness can be rehabilitated by bone-anchored hearing aids (BAHA). Whereas the conventional hearing aids transmit sound to the tympanic membrane via air conduction, the BAHA transmits sound via vibrations through the skull directly to the cochlea. It uses a titanium screw that penetrates the skin and needs life-long daily care; it may cause skin infection and redness. The BCI is developed as an alternative to the percutaneous BAHA since it leaves the skin intact. The BCI comprises an external audio processor with a transmitter coil and an implanted unit called the bridging bone conductor with a receiver coil. Using amplitude modulation of the Class-E power amplifier that drives the inductive link, the sound signal is transmitted to the implant through the intact skin. It was found that the BCI can generate enough output force level for candidate patients. Maximum power output of the BCI was designed to occur at 5-mm skin thickness and the variability was within 1.5 dB for 1-8-mm skin thickness variations.

A novel bone conduction implant (BCI): Engineering aspects and pre-clinical studies

Percutaneous bone anchored hearing aids (BAHA) are today an important rehabilitation alternative for patients suffering from conductive or mixed hearing loss. Despite their success they are associated with drawbacks such as skin infections, accidental or spontaneous loss of the bone implant, and patient refusal for treatment due to stigma. A novel bone conduction implant (BCI) system has been proposed as an alternative to the BAHA system because it leaves the skin intact. Such a BCI system has now been developed and the encapsulated transducer uses a non-screw attachment to a hollow recess of the lateral portion of the temporal bone. The aim of this study is to describe the basic engineering principals and some preclinical results obtained with the new BCI system. Laser Doppler vibrometer measurements on three cadaver heads show that the new BCI system produces 0–10 dB higher maximum output acceleration level at the ipsilateral promontory relative to conventional ear-level BAHA at speech frequencies. At the contralateral promontory the maximum output acceleration level was considerably lower for the BCI than for the BAHA.SumarioLos auxiliares auditivos anclados al hueso (BAHA) en forma percutánea son hoy en día una alternativa importante de rehabilitación para pacientes que sufren de pérdidas auditiva conductivas o mixtas. A pesar de su éxito, ellos se asocian con algunos problemas, tales como infecciones de la piel, pérdida accidental o espontánea del implante óseo, o el rechazo del paciente al tratamiento por razones de estigma. Se ha prop-uesto un novedoso sistema de implante de conducción ósea (BCI) que deja la piel intacta, como una alternativa al sistema BAHA. El sistema de BCI ha sido ya desarrollado y el transductor encapsulado utiliza una unión sin tornillo a un receso hueco en la porción lateral del hueso temporal. El objetivo de este estudio es describir los principios básicos de ingeniería y algunos resultados pre-clínicos obtenidos con el nuevo sistema BCI. Mediciones con un vibrómetro Laser Doppler sobre tres cabezas de cadáver muestran que el nuevo sistema BCI produce un nivel más alto de aceleración máxima de salida de 0–10 dB en el promontorio ipsilateral, en relación con el BAHA convencional a la altura del oído, en las frecuencias del lenguaje. En el promontorio contralateral, el nivel máximo de aceleración de salida fue considerablemente más bajo para el BCI que para el BAHA.

Bone-Anchored Hearing Aid Surgery in Older Adults: Implant Loss and Skin Reactions

We evaluated the clinical outcome measures of fixture loss and skin reactions in older-adult users of percutaneous bone-anchored hearing aids (BAHAs). We performed a retrospective analysis of 224 older adults (at least 60 years of age) who underwent implantation of 248 implants with the simplified Nijmegen surgical technique between January 1995 and May 2007. During a mean follow-up of 39 months (range, 0 to 144 months), 16 of the 248 implants were lost (6.5%). The causes were failed osseointegration in 9 cases, trauma in 6 cases, and implant loss in irradiated bone in 1 case. There were no losses due to infection. Implant loss was not significantly correlated with age. In 40 implants (16.9%), severe skin reactions of Holgers grade 2 or more were observed. Skin revision surgery was performed around 6 implants (2.4%). None of the patients had an 8.5-mm abutment to overcome severe skin reactions. The outcome of BAHA surgery in older adults was favorable. The rate of implant loss was comparable with that in the overall population of BAHA recipients. There were low risks of severe skin reactions or developing thick skin around the implant.

Percutaneous Versus Transcutaneous Bone Conduction Implant System

Percutaneous bone-anchored hearing aid (BAHA) is an important rehabilitation alternative for patients who have conductive or mixed hearing loss. However, these devices use a percutaneous and bone-anchored implant that has some drawbacks reported. A transcutaneous bone conduction implant system (BCI) is proposed as an alternative to the percutaneous system because it leaves the skin intact. The BCI transmits the signal to a permanently implanted transducer with an induction loop system through the intact skin. The aim of this study was to compare the electroacoustic performance of the BAHA Classic-300 with a full-scale BCI on a cadaver head in a sound field. The BCI comprised the audio processor of the vibrant sound bridge connected to a balanced vibration transducer (balanced electromagnetic separation transducer). Implants with snap abutments were placed in the parietal bone (Classic-300) and 15-mm deep in the temporal bone (BCI). The vibration responses at the ipsilateral and contralateral cochlear promontories were measured with a laser Doppler vibrometer, with the beam aimed through the ear canal. Results show that the BCI produces approximately 5 dB higher maximum output level and has a slightly lower distortion than the Classic-300 at the ipsilateral promontorium at speech frequencies. At the contralateral promontorium, the maximum output level was considerably lower for the BCI than for the Classic-300 except in the 1-2 kHz range, where it was similar. Present results support the proposal that a BCI system can be a realistic alternative to a BAHA.

Nijmegen Results with Application of a Bone-Anchored Hearing Aid in Children: Simplified Surgical Technique

A retrospective analysis was performed to evaluate the clinical outcome of percutaneous bone-anchored hearing aid (BAHA) application in children with the outcome measures of fixture loss and skin reactions. An analysis was done of 93 of the 101 children 16 years of age or younger who underwent the simplified Nijmegen surgical technique between January 1994 and July 2007. Twenty-one of 129 fixtures (16.3%) were lost or removed. In 12 cases, osseointegration failed. The majority of the fixture losses (86%) occurred within 1 year after surgery. No differences were found between 3 age groups or between fixture lengths (seven 3-mm implants versus fourteen 4-mm implants). The BAHA fixtures were less stable in children than in adults. In 8 cases, Holgers grade 4 skin reactions were noted at an average (+/-SD) of 5.5 +/- 4.7 months after surgery, ie, significantly sooner than the milder reactions (p = 0.001). In 28 cases (22%), skin reactions of Holgers grades 2 to 4 were observed. Revision surgery to reduce subcutaneous scar tissue was necessary in 22 implants (17%). Fixture loss was more frequent in children than in adults. The age of the child and the length of the fixture did not appear to influence fixture stability. Children should undergo frequent checkups at the outpatient clinic.

Intralesional triamcinolone acetonide injection in hypertrophic skin surrounding the percutaneous titanium implant of a bone-anchored hearing aid

We present a patient with persistent hypertrophic skin surrounding the percutaneous implant of a bone-anchored hearing aid system, successfully treated with intralesional applied corticosteroids. Case report and review of the world literature concerning bone-anchored hearing aid implantation and intralesional applied corticosteroids for the treatment of hypertrophic scars and keloids. Eight weeks after revision surgery to reduce surplus skin and subcutaneous scar tissue overgrowing the abutment, skin and subcutaneous scar tissue overgrowth reoccurred. As an alternative to yet another surgical procedure, the hypertrophic skin was treated with intralesional injections of triamcinolone acetonide. Three weeks after the treatment, a satisfying result was seen, and no subsequent relapse was observed. To our knowledge, this is the first, photographically well documented case report of a patient with persistent hypertrophic skin surrounding a percutaneous bone-anchored hearing aid implant, successfully treated with intralesional applied corticosteroids.

The BAHA Softband: A new treatment for young children with bilateral congenital aural atresia

To evaluate the validity of a bone-anchored hearing aid (BAHA) Softband (fitted unilaterally and bilaterally) in young children with bilateral congenital aural atresia. Two children with severe bilateral congenital conductive hearing loss, who had been fitted with a transcutaneous BAHA Softband at the age of 3 and 28 months, respectively. The latter child had been fitted with a conventional bone-conduction hearing aid at the age of 3 months; at 28 months, this child had received the BAHA Softband and after 5 months of unilateral application, the BAHA Softband was fitted bilaterally. Follow-up in the two children was 31 and 17 months, respectively. Using the artificial mastoid, gain and maximum output were studied in this new transcutaneous application of the BAHA, with the BAHA Classic and the BAHA Compact as sound processor. Results were compared to those obtained with a conventional bone-conduction device (Oticon E 300 P). Aided thresholds and sound lateralization scores were assessed with double visual reinforcement audiometry (VRA). To test the validity of the BAHA Softband, the speech and language development of the children was assessed by means of age-appropriate tests (the preverbal Symbolic play test and the Dutch non-speech test for receptive and expressive language and the Dutch version of the Reynell language test). The electro-acoustic measurements showed minor differences in gain between the three devices. At a reduced volume setting, the mean input level at which the output levelled off was largely comparable between the BAHA Classic and the conventional device, but somewhat poorer with the BAHA Compact. Both children showed speech and language development that was in accordance with their cognitive development. The BAHA Softband was a valid intervention in children with congenital bilateral aural atresia who were too young for percutaneous BAHA application.

Ten-year experience with percutaneous bone-anchored hearing aids: a 3- to 10-year follow-up Markham Stouffville Hospital, 1990 to 2000.

Patients with bilateral conductive hearing losses continue to be a source of frustration for both otologists and audiologists. Efforts to rehabilitate their hearing have included medical and surgical treatment, as well as the use of conventional hearing aids and, less frequently, conventional bone-conduction hearing aids. In the late 1980s, a percutaneous bone-anchored hearing aid (BAHA) developed by Dr. A. Tjellström, as an offshoot of Dr. P. I. Brånemark's work on osseointegration of titanium and bone, became commercially available. The BAHA has become a high-performing, comfortable, and aesthetically pleasing sound processor. The results of a 10-year BAHA program based at Markham Stouffville Hospital are summarized. In particular, a retrospective review of the 76 patients implanted between 1990 and 1997 is reported (i.e., a 3- to 10-year follow-up). Recent innovations to the design of the BAHA will be described that will further improve the quality of life for these patients.