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

Patients with a conductive hearing loss may find conventional hearing aids unsatisfactory for a variety of reasons. Efforts to overcome some of these difficulties have led to the development of the osteointegrated hearing aid. Implantable bone conduction hearing aids are an important advance in the treatment of well selected patients. Only 18 patients, who have been implanted with the Xomed Audiant bone conduction hearing aid, have so far been reported on in the UK. This report concerns a further six patients who have been implanted in one centre. Five of these patients continue to use their Audiant hearing aid 14 to 24 months after being fitted. They regard it to have significant advantages over their previous hearing aids. Four of the five patients use an ear level processor. Two of the patients who had previously used conventional bone conduction hearing aids now use the ear level processor.

An implantable bone conduction hearing aid is a device that assists hearing by transmitting sound vibration through the bone. It is suitable not only for patients with conductive hearing loss and congenital external aural atresia but also for those with unilateral hearing loss, chronic otitis media, or patients whose normal structure has been destroyed due to previous surgery. In this paper, we introduce a novel surgical technique for an implantable bone conduction hearing aid (BAHA<sup>®</sup> Attract) that can be performed through minimal incision in a short time under local anesthesia based on accurate anatomical characteristics. We believe this novel technique could provide convenience for patients and surgeons. Additionally, through this technique, we can expect that various types of implantable bone conduction hearing aids that function effectively and safely can be provided for patients.

Isolated oval window atresia (OWA) is a rare cause of congenital conductive middle ear deafness and may be overlooked owing to the normal appearance of the external ear. This anomaly has been previously described, although the published numbers with both imaging and surgical findings are few. Our aim is to correlate the imaging features of OWA with intraoperative findings. This is a single-centre retrospective evaluation of patients who were diagnosed with OWA and who received surgery from January 1999 to July 2006. No new case was diagnosed after 2006 to the time of preparation of this manuscript. High resolution computed tomography (HRCT) imaging of the temporal bones of the patients were retrospectively evaluated by 2 head and neck radiologists. Images were evaluated for the absence of the oval window, ossicular chain abnormalities, position of the facial nerve canal, and other malformations. Imaging findings were then correlated with surgical findings. A total of 9 ears in 7 patients (two of whom with bilateral lesions) had surgery for OWA. All patients had concomitant findings of absent stapes footplate with normal, deformed or absent stapes superstructure and an inferiorly displaced facial nerve canal. HRCT was sensitive in identifying OWA and associated ossicular chain and facial nerve abnormalities, which were documented surgically. OWA is a rare entity that can be diagnosed with certainty on HRCT, best visualised on coronal plane. Imaging findings of associated middle ear abnormalities, position of the facial nerve canal, which is invariably mal-positioned, and associated deformity of the incus are important for presurgical planning and consent.

The Bonebridge implant in older children and adolescents with mixed or conductive hearing loss: Audiological outcomes

Background Implantable bone-conduction hearing aids (BCHA) are effective in patients with congenital ear malformations.However, there is no large sample study to verify the efficacy of Bonebridge in patients with congenital oval window atresia. Objectives To investigate efficiency of implantable bone-conduction hearing aids in Mandarin-speaking patients with congenital oval window atresia Material and methods We retrospectively analyzed 15 patients, who were confirmed with either unilateral or bilateral congenital oval window atresia by temporal bone CT. All patients were implanted with a bone-conduction hearing device between July 2016 and July 2019 at Beijing Tongren Hospital, Capital Medical University. Pure tone audiometry (PTA), air-bone gap (ABG), speech discrimination scores (SDSs), and hearing thresholds were performed. Results Postoperative complications including facial paralysis were particularly rare. Unaided mean sound field threshold was 62.2 ± 10.5 dBHL and that with implantable bone-conduction hearing aids was 39.1 ± 13.2 dBHL (p < 0.01). The mean speech discrimination scores improved greatly (p < 0.01), specifically with regard to sentence and disyllabic words. Conclusions Patients with congenital oval window atresia often show moderate to severe conductive hearing loss. Implantable bone-conduction hearing aids are considerably safe and stable for hearing rehabilitation. It is a novel treatment modality for Mandarin-speaking patients with congenital oval window atresia.

Background: The persistent stapedial artery (PSA) is a rare congenital vascular malformation involving the middle ear. It is usually associated with pulsatile tinnitus and/or conductive hearing loss and can account for multiple risks during middle ear surgery. Case Report: we present a case of a 9-year-old male child with conductive hearing loss and persistent stapedial artery in his right ear, who was admitted to our ENT Department for hearing loss. During surgery, we discovered PSA along with congenital stapes agenesis and oval window atresia, as well as an abnormal trajectory of the mastoid segment of the facial nerve. After ossicular reconstruction (transcanal total ossicular replacement prosthesis) with cochleostomy, no surgical complications were recorded and hearing improvement was monitored by pre- and postoperative audiometry. Conclusion: Stapedial artery is a rare anatomical middle ear abnormality that can prevent proper surgical hearing restoration and can be associated with other simultaneous temporal bone malformations.

The purpose of this study is to categorize anomalous tympanic facial nerve (FN) on high-resolution computed tomography (HRCT) and to determinate the significance of associated temporal bone anomalies and congenital syndromes without microtia in patients with hearing loss. A retrospective analysis of HRCT findings in 30 temporal bones in 18 patients with anomalous FN was performed. Abnormalities of the tympanic FN were categorized as follows: category 1: FN medially positioned, but above the oval window; category 2: FN in the oval window niche; and category 3: FN below the oval window. Potential associated findings that were assessed included stapes abnormalities, oval window atresia, and inner ear anomalies, as well as the presence of a known congenital syndrome with hearing loss. The most common type of anomalous tympanic FN was category 1 (67%, n = 20), following by group 2 (20%, n = 6) and group 3 (13%, n = 4). Stapes anomalies were detected in 77% of temporal bones (n = 23), oval window atresia was detected in 43% of temporal bones (n = 13), and inner ear anomalies were detected in 70% of temporal bones (n = 21). Anomalous tympanic facial nerves in temporal bone with conductive hearing loss were often (60%) not associated with oval window atresia. The combination of aberrant tympanic FN and inner ear anomalies was significantly (P = .038) associated with a known congenital syndrome (6 patients), including CHARGE syndrome, oculo-auriculo-vertebral spectrum, Pierre-Robin sequences, and Down syndrome. Therefore, an anomalous tympanic FN in conjunction with inner ear anomalies appears to be a biomarker for certain congenital syndromes with hearing loss in the absence of microtia.

As the technology advances and bone conduction implant (BCI) use increases, implantable bone conduction hearing aids are regarded as a treatment method for single-sided deafness (SSD) and their efficacy on SSD must be discussed. Therefore, we organized the problems of SSD and types of implantable bone conduction hearing aids and explained their effectiveness in the treatment of SSD in terms of changes in 1) speech recognition in a noisy environment, 2) sound localization, 3) subjective satisfaction as assessed by questionnaire, and 4) tinnitus. Although bone conduction hearing aids do not significantly improve localization ability in SSD, they increase the ability to listen under noise, increasing subjective satisfaction. Tinnitus improvement was also reported. The active forms of BCI like MED-EL BONEBRIDGE®2 and Cochlear Osia®2 have been developed well. Based on these technological developments and effects, bone conduction hearing aids would be a good option for treatment option of SSD.

Oval window atresia (OWA) is a rare otologic condition often associated with a maximal conductive hearing loss, and variable ossicular and facial nerve canal (FNC) anomalies, which have contributed to suboptimal middle ear surgical outcomes. No grading scheme exists to detail the spectrum of associated temporal bone anomalies in OWA; therefore, our objectives were to complete an audiometric and radiographic review to characterize audiometric patterns of hearing loss, and refine the classification system for OWA to determine suitability for middle ear surgery. A retrospective audiometric and radiographic review was conducted at a pediatric tertiary care institution. Patients with OWA identified on temporal bone computerized tomography (CT) scans obtained from 01/2010 to 06/2024 were included. Audiological, radiological, and patient factors were analyzed. Thirty-one patients (48 ears) with OWA were identified. Across frequencies, the air-bone gap decreased significantly as frequency increased (ANOVA with pairwise comparisons, p < 0.001) due to a worsening of bone conduction thresholds and improvement in air conduction thresholds. The FNC was abnormal in 43/48 ears and was determined to overlay the oval window in 6 ears. Additional anomalies included inferiorly displaced, dehiscent, and duplicated canals. Ossicular anomalies were reported in 46/48 ears, and stapedial anomalies were most common. Our findings indicate OWA may manifest audiometrically with consistent and specific hearing loss characterized by a 60-80 dB ABG at lower frequencies that decreases above 2 kHz. CT findings of OWA show considerable variability. We propose a new classification system for OWA based on facial nerve position as this directly influences middle ear surgical feasibility.

Background: To assess and compare binaural benefits and subjective satisfaction of active bone conduction implant (BCI) in patients with bilateral conductive or mixed hearing loss fitted with bilateral BCI and patients with monaural conductive hearing loss fitted with monaural BCI. Methods: ITA Matrix test was performed both on patients affected by bilateral conductive or mixed hearing loss fitted with monaural bone conduction hearing implant (Bonebridge, Med-El) before and after implantation of contralateral bone conduction hearing implant and on patients with monaural conductive or mixed hearing loss before and after implantation of monaural BCI. The Abbreviated Profile of Hearing Aid Benefit (APHAB) questionnaire was administered to both groups of subjects and the results were compared with each other. Results: Patients of group 1 reported a difference of 4.66 dB in the summation setting compared to 0.79 dB of group 2 (p < 0.05). In the squelch setting, group 1 showed a difference of 2.42 dB compared to 1.53 dB of group 2 (p = 0.85). In the head shadow setting, patients of group 1 reported a difference of 7.5 dB, compared to 4.61 dB of group 2 (p = 0.34). As for the APHAB questionnaire, group 1 reported a mean global score difference of 11.10% while group 2 showed a difference of −4.00%. Conclusions: Bilateral BCI in patients affected by bilateral conductive or mixed hearing loss might show more advantages in terms of sound localisation, speech perception in noise and subjective satisfaction if compared to unilateral BCI fitting in patients affected by unilateral conductive hearing impairment. This may be explained by the different individual transcranial attenuation of each subject, which might lead to different outcomes in terms of binaural hearing achievement. On the other hand, patients with unilateral conductive or mixed hearing loss fitted with monaural BCI achieved good results in terms of binaural hearing and for this reason, there is no absolute contraindication to implantation in those patients.

In patients with conductive hearing loss caused by middle ear disorders or atresia of the ear canal, a Bonebridge implantation can improve hearing by providing vibratory input to the temporal bone. The expected results are improved puretone thresholds and speech recognition. In the European Union, approval of the Bonebridge implantation was recently extended to children. We evaluated the functional outcome of a Bonebridge implantation for eight adults and three children. We found significant improvement in the puretone thresholds, with improvement in the air-bone gap. Speech recognition after surgery was significantly higher than in the best-aided situation before surgery. The Bonebridge significantly improved speech recognition in noisy environments and sound localization. In situations relevant to daily life, hearing deficits were nearly completely restored with the Bonebridge implantation in both adults and children.

We present a rare adult case of bilateral oval and round window atresia. Clinical and audiologic findings were suggestive of otosclerosis. High resolution CT Temporal bones showed unequivocal findings of bilateral oval and round window atresia. Atresia of these windows is a rare temporal bone anomaly. Presentation as an adult can confound the clinicians and warranting a closer look on the CT for atretic windows and subtle signs of otosclerosis in patients with conductive hearing loss.

Objective: Bone conduction implants (BCI) are medical devices for conductive and mixed hearing losses as well as for single side sensorineural deafness (SSD). All direct-drive BCI transmit vibrations directly to the skull bone and can be divided into percutaneous and active transcutaneous devices. Method: We report a case series of 10 patients, suffered from mixed or conductive hearing loss, submitted to Bonebridge implantation. Audiological evaluation was conducted at six months to observe the functional impact of this device. Patients were asked to answer the Glasgow Benefit Inventory (GBI), a retrospective questionnaire, to measure the effect of the surgical intervention on the health-related quality of life. Results: The functional gain was found to range from 25 dB to 40 dB. Speech perception in noise improves in all patients and no post-operative complications were observed. GBI questionnaire has reflected high device satisfaction rate. Conclusion: Active transcutaneous BCI represent an effective and safety solution for people that cannot have adequate benefit from conventional hearing aids, to restore good audiological performance and life satisfaction.

To identify audiological and demographic variables that predict speech recognition abilities in patients with bilateral microtia who underwent Bonebridge (BB) implantation. Fifty patients with bilateral microtia and bilateral conductive hearing loss (CHL) who underwent BB implantation were included. Demographic data, preoperative hearing aid use experience, and audiological outcomes (including pure-tone hearing threshold, sound field hearing threshold [SFHT], and speech recognition ability) for each participant were obtained. The Chinese-Mandarin Speech Test Materials were used to test speech recognition ability. The word recognition score (WRS) of disyllabic words at 65dB SPL signals was measured before and after BB implantation in quiet and noisy conditions. The mean preoperative WRS under quiet and noisy conditions was 10.44 ± 12.73% and 5.90 ± 8.76%, which was significantly improved to 86.38 ± 9.03% and 80.70 ± 11.34%, respectively, following BB fitting. Multiple linear regression analysis revealed that lower preoperative SFHT suggested higher preoperative WRS under both quiet and noisy conditions. Higher age at implantation predicted higher preoperative WRS under quiet conditions. Furthermore, patients with more preoperative hearing aid experience and lower postoperative SFHT were more likely to have higher postoperative WRS under both quiet and noisy testing conditions. This study represents the first attempt to identify predictors of preoperative and postoperative speech recognition abilities in patients with bilateral microtia with BB implantation. These findings emphasize that early hearing intervention before implantation surgery, combined with appropriate postoperative fitting, contributes to optimal benefits in terms of postoperative speech recognition ability.

Patients with air-bone gaps who cannot be corrected successfully by tympanoplasty or with mixed hearing loss may be treated with bone conduction hearing aids. Their disadvantages are the obvious external fixation components or the biological and psychosocial problems of open implants. We have developed new partially implantable bone conduction hearing aid without a percutaneous abutment and have been using them clinically for 4 years. The principle of these bone conduction hearing aids is a magnetic coupling and acoustic transmission between implanted and external magnets. The goal of this study was to evaluate clinical and audiological results. Magnets are implanted into shallow bone beds in a one step procedure. The skin above the magnets is also reduced to a thickness of 4-5 mm, which reduces the attenuation to less than 10 dB compared to direct bone stimulation. Over 100 patients have been implanted in the last 5 years. Except for temporary pressure marks in 4%, which healed after careful shimming of the external base plate, there were no other complications. The holding strength of the external components is equivalent to partially implantable hearing aids and cochlea implants and the hearing improvement is similar to other bone conduction hearing aids. We have found the comfort and safety of this system is significantly improved compared to conventional or percutaneous bone conduction hearing aids.