Audiological effect of bone-anchored hearing aid

The bone-anchored hearing aid (BAHA) has proved to be a valuable alternative to conventional air and bone conduction hearing aids for patients suffering from chronic otitis media or bilateral aural atresia. The BAHA gave better sound quality and greater comfort than conventional hearing aids (HAs), but only 1 study has been done in Japan. We implanted BAHAs in 6 hard-of-hearing patients in the last 2 years. One patient suffered skin problems around the abutment and used the BAHA only briefly. Free-field audiometry, the speech discrimination test (SDT), and the speech recognition test (SRT) were conducted in all subjects. They were evaluated either with the HA or BAHA. The SDT and SRT showed better hearing results in quiet for the BAHA than the conventional HA, but there was a minimum difference in SDT and SRT in noise. Subjects assessed the HA and BAHA using questionnaires. Subjects reported that the BAHA offers a number of important advantages, including greater cosmetic acceptability, improved speech intelligibility, and better sound quality.     

Clinical experience with the bone-anchored hearing aid

Patients operated on for chronic otitis media sometimes have problems with persistent discharge from the ear when using a conventional hearing aid with an ear mould located in the ear canal. A new technique where a hearing aid for bone-conducted sound is mounted on an osseointegrated titanium screw located in the mastoid area is available. The method was evaluated in a routine clinical setting outside the centre of development. Eight patients were fitted with the new hearing aid. All improved regarding the drainage from the ears. The patients were all very satisfied with the hearing results and with the hearing aid, from a practical as well as from a cosmetic point of view. No complications were noted during an observation period of minimum 12 months.     

Results of the bone-anchored hearing aid in unilateral hearing loss

OBJECTIVES: The advantages of binaural hearing are well established and universally accepted. However, a tendency remains to withhold the benefits of binaural hearing to adults and children with one normal ear. The purpose of this study is to demonstrate the benefit of the bone-anchored hearing aid (BAHA) in a group of patients with unilateral conductive or mixed hearing loss. STUDY DESIGN: This is a prospective study of nine patients (five males and four female patients) with conductive or mixed hearing loss who met the criteria for BAHA except for having normal hearing in the other ear. They had congenital aural atresia or mastoidectomies secondary to chronic ear infections with or without cholesteatoma or had a temporal bone tumor excised METHODS: Patients had evaluations before and after implantation, including audiological testing and responses to a standardized hearing handicap questionnaire. Statistical analyses of the data were made using the Wilcoxon signed rank test and the paired Student t test for repeated measures. RESULTS: All patients had tonal and spondee threshold improvement with BAHA when compared with thresholds before treatment. Speech recognition performance in BAHA-aided conditions was comparable to the patient's best score in unaided condition. Patients reported a significant improvement in their hearing handicap scores with the BAHA. CONCLUSIONS: The use of BAHA has significantly improved the hearing handicap scores in patients with unilateral conductive or mixed hearing loss. The proven safety and efficacy of the device promote its use in unilateral cases that traditionally had been left unaided.     

Results of pediatric bone-anchored hearing aid implantation

INTRODUCTION: The bone-anchored hearing aid (BAHA) system uses an osseointegrated titanium implant to propagate sound directly to the inner ear through the bones of the skull, bypassing the impedance of the skin and subcutaneous tissues. Children as young as 18 months have had hearing rehabilitated with this device. OBJECTIVES: The goals were to evaluate the efficacy of patient selection criteria, the safety and effectiveness of the implantation procedure, and the level of patient satisfaction after BAHA implantation in children. METHODS: The records of all pediatric patients implanted in Edmonton were retrospectively reviewed. Twenty patients, who received 25 implants, with postimplantation follow-up of 6 months or greater, were included. The average follow-up was 3 years, 7 months. RESULTS: Of 20 original implants, 3 were lost owing to trauma, whereas 2 failed to osseointegrate. All were successfully reimplanted. Complications related to the implants included three instances of skin necrosis around the abutment. All patients and caregivers reported greater than 95% improvement in patient-identified listening situations. Pure-tone averages improved from a mean of 49 dB for the better hearing ear preoperatively to 16 dB with the BAHA set at normal listening levels. CONCLUSIONS: The BAHA provides a safe and effective means of rehabilitation of conductive or mixed hearing loss in the pediatric population. Our patients report a high level of satisfaction and continued use of their devices.     

The bone-anchored hearing aid for children: recent developments

In 1984 the Bone-Anchored Hearing Aid, or BAHA, system was introduced. Its transducer is coupled directly to the skull percutaneously to form a highly effective bone-conduction hearing device. Clinical studies on adults with conductive hearing loss have shown that the BAHA system outperforms conventional bone-conduction hearing aids. Therefore, the next step was to apply the BAHA system in children with congenital or acquired conductive hearing loss. Reviewed data showed that, on average, such children benefited significantly more from the BAHA than from reconstructive surgery. Thus, BAHA application appears to be the best option to achieve normal communication and speech and language development in children with bilateral conductive hearing loss. However, in children under the age of three to four years, a conventional solution must be applied, e.g. a bone conductor with a transcutaneous coupling, because they are too young to undergo BAHA implant surgery. In the case of unilateral congenital conductive hearing loss, there is no convincing evidence in the clinical literature for early intervention. In summary, the BAHA system can be considered a new, indispensable tool for children with bilateral conductive hearing loss.     

The bone-anchored hearing aid: quality-of-life assessment

OBJECTIVES: To assess the impact of a bone-anchored hearing aid (BAHA) on the quality of life (QOL) of adults and to test the hypothesis that a BAHA improves QOL because otorrhea and/or skin irritations decrease. DESIGN: Prospective postal-based questionnaire study using validated health-related QOL instruments, combined with hearing-aid-related questions. PATIENTS AND METHODS: The study included 56 consecutive adult patients with acquired conductive or mixed hearing loss who were scheduled for BAHA implantation at the University Medical Centre Nijmegen, Nijmegen, the Netherlands. All 56 patients completed the 36-Item Short-Form Health Survey (SF-36), the EuroQol-5D (EQ-5D), and the Hearing Handicap and Disability Inventory (HHDI); 36 patients had been using an air-conduction hearing aid (ACHA) and 20 patients a conventional bone-conduction hearing aid (CBHA). Questionnaires were filled out before surgery and after 6 months of experience with the BAHA. RESULTS: In the SF-36 group, there was significant improvement in the scores of the mental health domain (P =.02). When the SF-36 patients were classified according to previous hearing aid, there was no statistically significant change in the scores in any of the domains. In the EQ-5D group and in its ACHA and CBHA subgroups, there were no important differences in the results before and after the patients received their BAHAs. In the HHDI group, the handicap and disability scales showed significant improvement (P<.01) irrespective of the type of previously worn hearing aid. CONCLUSIONS: Overall, generic health-related QOL was not influenced significantly by the use of a BAHA according to the SF-36 and the EQ-5D. The more disease-specific scales (HHDI) did show improved QOL with a BAHA.     

骨锚式助听器植入手术临床分析

目的 通过分析骨锚式助听器(bone-anchored hearing aid,BAHA)植入患者临床资料,探讨BAHA植入手术的适应证、手术方式及效果.方法 回顾性分析16例BAHA植入患者的临床资料,其中男9例,女7例;年龄8 ～53岁,平均31岁;外中耳畸形9例,慢性化脓性中耳炎术后2例,耳硬化症2例,单侧重度感音神经性聋3例.术前进行纯音测听、言语识别率测试、颞骨CT等评估,术后3个月左右开机时测试助听后的声场纯音听阈和言语识别率.结果 术后随访4 ～16个月,未见明显术后并发症.16例患者术前平均气导听阈(x±s,下同)为(63.2±19.0)dB HL,术后声场下助听听阈为(35.5±10.9)dB HL.术后噪声下言语识别率测试较术前提高了37.0％ ±31.7％,术后单音节言语识别率测试较术前提高了76.0％±19.7％.结论 BAHA是一种临床上安全、有效的人工听觉植入装置,在严格选择适应证的前提下可以在临床推广应用.     

骨锚式助听器的发展及应用

骨锚式助听器(bone-anchored hearing aid,BAHA)是一种通过骨传导方式改善听力的助听设备,也是惟一直接经过骨传导方式工作的植入式助听装置。BAHA的发展和应用是从20世纪70年代开始,它的出现为那些不适用气传导助听装置的患者带来了福音。经过30多年的发展和不断改     

The implant-site split-skin graft technique for the bone-anchored hearing aid 1

We describe the technique of implant-site split-skin grafting for the bone-anchored hearing aid (BAHA). Twenty-five patients have undergone this procedure (20 adults and five children) since 1993 with a minimum follow-up of 1 year. Fifteen adults were operated upon as single stage surgery, all other cases (including all children) were performed in two stages. In four patients (16%) significant early graft inflammation was encountered which settled with outpatient treatment. In one the abutment had to be temporarily removed to allow the graft to settle. All patients now have a stable graft site. This surgical technique is straightforward and a separate graft donor site is avoided. It would appear this technique results in a stable BAHA graft site with low associated morbidity.     

Clinical results with a percutaneous bone-anchored hearing aid

During a 2-year period ending in July 1987, nine patients were implanted with a percutaneous bone-anchored hearing aid developed at the University of Gothenburg and Chalmers University of Technology, Sweden. Patient selection was based on the presence of conductive or mixed hearing loss in patients who are unable to wear a conventional hearing aid because of infection or ear canal problems. Patients had speech discrimination scores of at least 60% for phonetically balanced monosyllables (CID lists) at 40 dB above threshold, and a pure tone bone conduction average of 45 dB hearing loss or better. Patients were evaluated in sound field, preoperatively and postoperatively using warble tones, speech reception threshold, speech discrimination, and synthetic speech identification. The patient's unaided hearing and hearing with a bone-anchored hearing aid were compared with the patient's hearing with a standard bone conduction hearing aid. Signal to noise ratio testing with the synthetic speech identification test demonstrated that the bone-anchored hearing aid was comparable to a standard bone conduction aid. There were no complications in our series. Five patients who reported otorrhea with conventional hearing aids experienced no otorrhea after implantation. Patient satisfaction, as assessed by questionnaire, revealed that all patients preferred the bone-anchored hearing aid to previously worn hearing aids.     

The implant-site split-skin graft technique for the bone-anchored hearing aid.

We describe the technique of implant-site split-skin grafting for the bone-anchored hearing aid (BAHA). Twenty-five patients have undergone this procedure (20 adults and five children) since 1993 with a minimum follow-up of 1 year. Fifteen adults were operated upon as single stage surgery, all other cases (including all children) were performed in two stages. In four patients (16%) significant early graft inflammation was encountered which settled with outpatient treatment. In one the abutment had to be temporarily removed to allow the graft to settle. All patients now have a stable graft site. This surgical technique is straightforward and a separate graft donor site is avoided. It would appear this technique results in a stable BAHA graft site with low associated morbidity.     

Latent demand for the bone-anchored hearing aid: the Lippy Group experience.

OBJECTIVE: The usefulness of the bone-anchored hearing aid (BAHA) for conductive and mixed hearing losses and recently for single-sided deafness has been well documented. Less clear is the number of patients who might benefit from the BAHA and how many would be interested in having the surgery. The purpose of this investigation is to examine these latter issues from the perspective of an otology practice. STUDY DESIGN: Retrospective review. SETTING: Private otology practice. PATIENTS: Approximately 44,000 patient records were reviewed. On the basis of this review, 617 patients were sent a letter describing the BAHA and explaining that they might be candidates. One hundred sixty-two of these patients made an appointment to be evaluated for the BAHA. METHODS: Patients who responded to the BAHA letter underwent an otologic and audiological evaluation to confirm their candidacy. The BAHA surgery and device were described, and interested patients tried the BAHA test band in the office. Patient responses to the BAHA were noted. RESULTS: Approximately 1.4% of the cases reviewed (617/44,000) were considered to be potential BAHA candidates. One hundred forty-six of the 162 patients who scheduled a BAHA evaluation were confirmed to be candidates. After seeing and learning about the BAHA, 92% of the verified candidates wanted to try the BAHA test band. Most patients who tried the test band (92%) liked the BAHA, and nearly a third (30.6%) had BAHA surgery. Patients with conductive or mixed hearing loss who tried the test band were more likely to have BAHA surgery than those with single-sided deafness (45.8% versus 27.3%). The major limiting factor was infrequent or inadequate insurance coverage for the procedure or device. CONCLUSIONS: Although the percentage of patients in an otology practice who could benefit from the BAHA is small, finding and alerting potential BAHA candidates are worthwhile.     

The bone-anchored hearing aid: a solution for previously unresolved otologic problems

A major challenge for otologists treating middle ear infection is to obtain a dry ear and optimal hearing. If the patient needs amplification and uses an air conduction hearing aid, the ear mold, occluding the ear canal, may provoke or aggravate the infection in the middle ear and thus cause otorrhoea. Continuous otorrhoea may cause cochlear damage in the long run. Bone conduction hearing aids offer an alternative for such patients.     

An intra-individual comparison of the previous conventional hearing aid with the bone-anchored hearing aid: The Nijmegen group questionnaire

By spring 2000, a total of 351 patients were implanted in the Birmingham bone-anchored hearing aid (BAHA) programme. This group consisted of 242 adults and 109 children. The aim of this retrospective questionnaire study was to directly assess patient satisfaction with their current bone-anchored hearing aid in comparison with their previous conventional air and/or bone-conduction hearing aids. The Nijmegen group questionnaire was sent by post to 312 patients who used their BAHA for six months or longer. The questionnaire used was first described by Mylanus et al. (Nijmegen group) in 1998. The total response rate was 72 per cent (227 of 312 patients). The bone-anchored hearing aid was found to be significantly superior to prior conventional hearing aids in all respects.     

A bone-anchored hearing aid for patients with pure sensorineural hearing impairment: a pilot study

This pilot study assesses the potential benefits of an optimized bone-anchored hearing aid (BAHA) for patients with a mild to moderate pure sensorineural high frequency hearing impairment. The evaluation was conducted with eight first-time hearing aid users by means of psycho-acoustic sound field measurements and a questionnaire on subjective experience; all of the patients benefited from the BAHA. On average, the eight patients showed improvement in PTA threshold of 3.4 dB and in speech intelligibility in noise of 14%. Seven of the subjects, also fitted with present standard air conduction hearing aids (ACHA) found the ACHA thresholds to be improved more than the BAHA ones. In speech tests, the ACHA was only slightly better; these patients chose between their different hearing aids according to the sound environment. Although the BAHA was preferred for wearing and sound comfort, it cannot be used as the sole aid for patients with pure sensorineural impairment.     

An alternate approach for surgical dressing of bone-anchored hearing aid abutment sites

OBJECTIVE: To present an alternative surgical dressing for bone-anchored hearing aid (BAHA) abutment sites, comparing it with the manufacturer's recommended "healing cap" in terms of split thickness skin graft (STSG) survival. STUDY DESIGN AND SETTING: A retrospective review of 30 patients who underwent unilateral BAHA implantation at a tertiary referral center. Patients were divided into two groups on the basis of the surgical dressing for the BAHA abutment site. Group 1 had a "healing cap" dressing, and group 2 had a bolster dressing. STSG survival was evaluated. RESULTS: Between May 2002 and July 2006, 30 patients underwent BAHA implantation. Seven patients received the "healing cap" dressing, and 23 patients received the bolster dressing. There was 100% STSG survival in the bolster dressing group and 71% skin graft survival in the healing cap group (P = .048). CONCLUSION: A traditional bolster dressing had improved STSG survival as compared with the manufacturer's recommended "healing cap." Additional benefits of a bolster are that it is maintenance free, well suited for noncompliant patients, and inexpensive.