Electroacoustic evaluation of the bone conduction transducer B250 for vestibular and hearing diagnostics in comparison with Radioear B71 and B81.

Objective: The objective is to evaluate the electroacoustic performance of the B250 transducer and to compare it with the two most widely used audiometric transducers B71 and B81.

Design: The electroacoustic performance was evaluated in terms of sensitivity level, distortion, maximum hearing level and electrical impedance.

Study Sample: Six B250 prototype transducers were evaluated and compared with published data of B71 and B81 together with complementary measurements of maximum hearing level at 125 Hz and phase of electrical impedance.

Objective verification of audibility in bone conduction devices.

Objective: To objectively measure audibility in patients wearing bone conduction devices (BCDs) with a new approach using a skin microphone at the patient's forehead.

Design: The skin microphone was attached by a softband and shielded by an earmuff. This set-up was confirmed not to be influenced by neither noise floor nor sound bypassing the BCD.

Ankle Audiometry: A Clinical Test for the Enhanced Hearing Sensitivity for Body Sounds in Superior Canal Dehiscence Syndrome.

Introduction: The aim of this study was to develop a clinical test for body sounds' hypersensitivity in superior canal dehiscence syndrome (SCDS).

Method: Case-control study, 20 patients affected by SCDS and body sounds' hypersensitivity and 20 control matched subjects tested with a new test called ankle audiometry (AA). The AA consisted of a psychoacoustic hearing test in which the stimulus was substituted by a controlled bone vibration at 125, 250, 500, and 750 Hz, delivered at the medial malleolus by a steel spring-attached bone transducer prototype B250.

Long-term follow-up and review of the Bone Conduction Implant.

Active transcutaneous bone conduction devices are a type of bone conduction device developed to keep the skin intact and provide direct bone conduction stimulation. The Bone Conduction Implant (BCI) is such a device and has been implanted in 16 patients. The objective of this paper is to give a broad overview of the BCI development to the final results of 13 patients at 5-year follow-up.

A novel method for objective in-situ measurement of audibility in bone conduction hearing devices - a pilot study using a skin drive BCD.

Objective: Objective measurement of audibility (verification) using bone conduction devices (BCDs) has long remained an elusive problem for BCDs. For air conduction hearing aids there are well-defined and often used objective methods, and the aim of this study is to develop an objective method for BCDs.

Design: In a novel setup for audibility measurements of bone-anchored hearing aid (BAHA) attached via a soft band, we used a skin microphone (SM) on the forehead measuring in-situ sound field thresholds, maximum power output (MPO) and international speech test signal (ISTS) responses.

Bone Conduction Stimulated VEMP Using the B250 Transducer.

Objective: Bone conduction (BC) stimulation is rarely used for clinical testing of vestibular evoked myogenic potentials (VEMPs) due to the limitations of conventional stimulation alternatives. The aim of this study is to compare VEMP using the new B250 transducer with the Minishaker and air conduction (AC) stimulation.

Methods: Thirty normal subjects between 20 and 37 years old and equal gender distribution were recruited, 15 for ocular VEMP and 15 for cervical VEMP.

Three-Year Follow-Up with the Bone Conduction Implant.

Background: The bone conduction implant (BCI) is an active transcutaneous bone conduction device where the transducer has direct contact to the bone, and the skin is intact. Sixteen patients have been implanted with the BCI with a planned follow-up of 5 years. This study reports on hearing, quality of life, and objective measures up to 36 months of follow-up in 10 patients.

The bone conduction implant - a review and 1-year follow-up.

The objective of this study is to evaluate its safety and effectiveness of the bone conduction implant (BCI) having an implanted transducer and to review similar bone conduction devices. This is a consecutive prospective case series study where the patients were evaluated after 1, 3, 6 and 12 months. Outcome measures were focussed on intraoperative and postoperative safety, the effectiveness of the device in terms of audiological performance and patient's experience.

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.

Nasal sound pressure as objective verification of implant in active transcutaneous bone conduction devices.

Active transcutaneous bone conduction devices consist of an external audio processor and an internal implant under intact skin. During the surgical procedure, it is important to verify the functionality of the implant before the surgical wound is closed. In a clinical study with the new bone conduction implant (BCI), the functionality of the implant was tested with an electric transmission test, where the output was the nasal sound pressure (NSP) recorded in the ipsilateral nostril.

Robustness and lifetime of the bone conduction implant - a pilot study.

Objectives: The objective of this study was to develop methods for evaluating the mechanical robustness and estimating the lifetime of the novel bone conduction implant (BCI) that is used in a clinical study. The methods are intended to be applicable to any similar device.

Materials And Methods: The robustness was evaluated using tests originally developed for cochlear implants comprising a random vibration test, a shock test, a pendulum test, and an impact test.

VEMP using a new low-frequency bone conduction transducer.

Objective: A new prototype bone conduction (BC) transducer B250, with an emphasized low-frequency response, is evaluated in vestibular evoked myogenic potential (VEMP) investigations. The aim was to compare cervical (cVEMP) and ocular (oVEMP) responses using tone bursts at 250 and 500 Hz with BC stimulation using the B250 and the conventional B81 transducer and by using air conduction (AC) stimulation.

Methods: Three normal subjects were investigated in a pilot study.

Direct bone conduction stimulation: Ipsilateral effect of different transducer attachments in active transcutaneous devices.

Active transcutaneous bone conduction devices, where the transducer is implanted, are used for rehabilitation of hearing impaired patients by directly stimulating the skull bone. The transducer and the way it is attached to the bone play a central role in the design of such devices. The actual effect of varying the contact to bone has not been addressed yet.

Vibrotactile Thresholds on the Mastoid and Forehead Position of Deaf Patients Using Radioear B71 and B81.

Objectives: The main objective of this study was to measure the vibrotactile thresholds on the mastoid process and forehead positions using patients with bilateral deafness and to compare the results from the two bone conduction vibrators Radioear B71 and B81.

Design: There is a possibility that the vibrotactile sensation on the skin makes it difficult to discriminate between sound and vibration. The risk is highest for patients who have bone conduction hearing thresholds in proximity to or worse than their vibrotactile thresholds.

Touch and Hearing Mediate Osseoperception.

Osseoperception is the sensation arising from the mechanical stimulation of a bone-anchored prosthesis. Here we show that not only touch, but also hearing is involved in this phenomenon. Using mechanical vibrations ranging from 0.

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

Hypothesis: 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.

Background: 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.

Magnetic resonance imaging investigation of the bone conduction implant - a pilot study at 1.5 Tesla.

Purpose: The objective of this pilot study was to investigate if an active bone conduction implant (BCI) used in an ongoing clinical study withstands magnetic resonance imaging (MRI) of 1.5 Tesla. In particular, the MRI effects on maximum power output (MPO), total harmonic distortion (THD), and demagnetization were investigated.

Technical design of a new bone conduction implant (BCI) system.

Objective: The objective of this study is to describe the technical design and verify the technical performance of a new bone conduction implant (BCI) system.

Design: The BCI consists of an external audio processor and an implanted unit called the bridging bone conductor. These two units use an inductive link to communicate with each other through the intact skin in order to drive an implanted transducer.

The bone conduction implant: Clinical results of the first six patients.

Objective: To investigate audiological and quality of life outcomes for a new active transcutaneous device, called the bone conduction implant (BCI), where the transducer is implanted under intact skin.

Design: A clinical study with sound field audiometry and questionnaires at six-month follow-up was conducted with a bone-anchored hearing aid on a softband as reference device.

Study Sample: Six patients (age 18-67 years) with mild-to-moderate conductive or mixed hearing loss.

Electro-acoustic performance of the new bone vibrator Radioear B81: a comparison with the conventional Radioear B71.

Objective: The objective is to evaluate the electro-acoustic performance of a new audiometric bone vibrator, the B81 from Radioear Corporation, USA. Comparison will be made with the widely used B71 which has well-known limitations at low frequencies.

Design: The B81 is based on the balanced electromagnetic separation transducer (BEST) principle where static forces are counterbalanced so that nonlinear distortion forces are reduced and maximum hearing levels can be increased.

MRI induced torque and demagnetization in retention magnets for a bone conduction implant.

Performing magnetic resonance imaging (MRI) examinations in patients who use implantable medical devices involve safety risks both for the patient and the implant. Hearing implants often use two permanent magnets, one implanted and one external, for the retention of the external transmitter coil to the implanted receiver coil to achieve an optimal signal transmission. The implanted magnet is subjected to both demagnetization and torque, magnetically induced by the MRI scanner.

The bone conduction implant--first implantation, surgical and audiologic aspects.

Objective: To report on preoperative assessment, surgery, and audiologic outcome of the first patient implanted with the bone conduction implant (BCI).

Background: The BCI is a bone conduction hearing device with an intact skin solution where the transducer is implanted close to the ear canal opening. By avoiding a percutaneous screw attachment to the skull, the BCI is anticipated to reduce complications associated with the Bone-Anchored Hearing Aid (BAHA) solution.