Development and Optimization of Universal Bone Conduction Hearing Spectacles

Background: Non-implantable bone anchored hearing devices (BCHDs) are utilized for patients with conductive or mixed hearing loss who are unsuitable for conventional hearing aids or have unresolved middle ear issues. These devices can be surgically implanted or attached using adhesive plates, dental sticks, elastic headbands, or bone conduction spectacles. Optimal fitting of bone conduction spectacles requires appropriate frame selection and contact pressure in the temporal and mastoid areas. The ANSI S3.6 and DIN EN ISO 389-3 standards recommend a contact area of approximately 1.75 cm2 and a maximum force of 5.4 N for effective sound transmission and comfort. Methods: This study aimed to evaluate the technical fit and mechanical stability of universal bone conduction hearing spectacles compared to established systems. A Sen-Pressure 02 thin-film sensor connected to an Arduino Uno R3 board measured contact force in the temporal and mastoid areas. Several BCHDs were tested, including the Bruckhoff la belle BC D50/70, Radioear B71 headset, Radioear B71 elastic headband, Cochlear Baha SoundArc M, and Cochlear Baha elastic headband, on a PVC artificial head, with data analyzed using ANOVA and LSD post hoc tests. Results: The la belle BC D50/70 spectacles showed comparable contact force to established BCHDs, ensuring adequate sound transmission and comfort. Significant differences were observed between the systems, with the Radioear B71 headset exhibiting the highest forces. The la belle BC D50/70 had similar forces to the Radioear B71 elastic headband. Conclusion: The la belle BC D50/70 universal bone conduction hearing spectacles are a technically equivalent alternative to established BCHDs, maintaining pressure below 5.4 N. Future research should explore the impact of different contact forces on performance and comfort, and the integration of force control in modified spectacles. This study indicates that the la belle BC D50/70 is a viable alternative that meets audiological practice requirements.

Does bilateral otosclerosis make pre-operative bone conduction more inaccurate?

Objectives:To assess whether bilateral otosclerosis renders pre-operative bone conduction more inaccurate by increasing the Carhart effect.Methods:Retrospective review of a database of pre and post-operative audiograms of 745 ears with otosclerosis treated with stapedectomy from 2013 to 2020 in a tertiary centre.Main outcome measures:Change in bone conduction after stapedectomy for otosclerosis in:unilateral otosclerosis(U1);bilateral otosclerosis undergoing first side surgery(B1);bilateral otosclerosis undergoing second side surgery(B2).The magnitude of change in bone conduction post-operatively within and between each group.Results:The average difference in pre and post-operative bone conduction was significant within in all groups(T-stat>2 and P-value<0.05)with the greatest change observed in the U1 group.Analysis of average change in bone conduction between groups did not reach statistical significance(Pvalue=0.37).Analysis of change per frequency demonstrated the greatest change in bone conduction post-operatively at 2000 Hz in all groups.The magnitude of change at 2000 Hz was the greatest in the bilateral groups;however,it did not reach statistical significance when compared to the unilateral group(P-value=0.36).Conclusions:This is the first study in the literature to assess the accuracy of pre-operative bone conduction in bilateral versus unilateral otosclerosis.There is no evidence that pre-operative bone conduction in bilateral otosclerosis is more inaccurate than in unilateral disease.In order to assess accuracy of pre-operative bone conduction in otosclerosis a reliable method of assessing post-operative bone conduction is required,without assumption of its equivalence to cochlear reserve.

Bone Auditory Thresholds Variations in Cholesteatoma Middle Ear Surgery

Objective: To investigate the changes of bone auditory thresholds variations in cholesteatoma middle ear surgery and its related factors and its related factors. Methods: 122 cases (122 ears) of unilateral cholesteatoma otitis media were treated by mastoidectomy and/or tympanoplasty plus stage I tympanoplasty, and tragus cartilage ring-cartilage membrane (Referred to as cartilage group, 62 ears) and temporalis muscle fascia (Referred to as fascia group, 60 ears) were used as tympanic membrane grafts respectively. The changes of bone conduction hearing threshold were compared between the two groups before and 1, 3, 6 months and 1, 3 years after operation. And compare the difference in the incidence of ossicular chain fixation or necrosis, vestibular window or cochlear window dysfunction between the two groups of patients with increased (positive) and decreased (negative) bone conduction threshold before operation. Results: Compared with the healthy side, 95 ears of 122 ears in the two groups had higher bone conduction hearing threshold before operation. Among them, 48 ears were in cartilage group and 47 ears were in fascia group;In 72 ears (76.34%) of these cases, the bone conduction hearing threshold decreased after operation, and the difference between the two groups was statistically significant (P Conclusion: The improvement of bone conduction hearing threshold in patients with cholesteatoma otitis media is mainly related to the fixation or necrosis of ossicular chain and the dysfunction of two windows. The tragus cartilage ring-perichondrium tympanoplasty can not only reduce the air-bone conduction difference, but also reduce the bone conduction hearing threshold, which has the advantage of stable and lasting hearing improvement.

Contemporary solutions for patients with microtia and congenital aural atresia-Hong Kong experience

Managing microtia patients is always a challenge. Multidisciplinary approach, good family support, well established doctorepatient rela-tionship and well organised patient-support groups are the essential elements for success. With the advancement of implantable hearing devices, more options will be available for the microtia patients. Otologists play a leading role in the whole management process. They not only provide proper guidance to the patients in choosing the correct path of the treatment, but also play a key role in organising and maintaining a cost-effective multidisciplinary rehabilitation team for the microtia patients.