Historical Background of Bone Conduction Hearing Devices and Bone Conduction Hearing Aids

Abstract

During the last 20 years, bone-anchored hearing aids (Baha(®)) became a familiar solution in the treatment of some types of hearing loss. The aim of this chapter is to present the different historical steps which have permitted the production of this new bone conduction hearing device. The recognition of bone conduction hearing is old and was known at least in Antiquity. During the Renaissance, Girolamo Cardano demonstrated a method by which sound may be transmitted to the ear by means of a rod or the shaft of a spear held between one's teeth: this was the beginning of teeth stimulators to improve hearing, firstly in connection with a musical instrument and then, in the second part of the 19th century, with the speaker. The development of the carbon microphone at the beginning of the 20th century allowed the construction of the bone conduction vibrator placed on the mastoid area, notably supported by eyeglasses since the 1950s. Confronted by various problems, and notably the loss of part of sound in the soft tissue of the external mastoid, the idea to implant the vibrator into the mastoid bone was developed in Göteborg, and the first Baha was implanted in 1977 by Anders Tjellström. From that date, various improvements allowed the development of the actual Baha. These different steps are presented in this study, supported by original documentation.

A new transcutaneous bone anchored hearing device - the Baha® Attract System: the first experience in Turkey

“…These devices can be used by adapting them to a headband, glasses, tooth or bone anchored titanium implants. [2] Among these devices, the Baha ® directly transmits sound vibrations to the temporal bone via a titanium abutment. Thereby, it can provide a high quality sound transmission and with this feature, percutaneous Baha ® implants are accepted as the gold standard therapy for bone conduction hearing loss.…”

Simulation of the power transmission of bone-conducted sound in a finite-element model of the human head

“…The gray area superior to the stimulation position shows the area for computation of sound power exchange between the skull bone and skull interior and the gray area around the stimulation position is the area for the same computations including the stimulation position layers of dense cortical bone. The excitation is provided at the mastoid skull bone using a triangular prism shaped mass to simulate a screw implanted through the outer layer of the cortical bone and the diploë similar to stimulations with bone anchored hearing aids (BAHA) (Berger 1976;Mudry and Tjellström 2011). The parameter values for the eight domains were obtained from the literature and are provided in Chang et al (2016).…”

Effects of Skin Thickness on Cochlear Input Signal Using Transcutaneous Bone Conduction Implants

“…BC hearing has been acknowledged for many centuries, and early designs used a sound processor (or sound source) held to a tooth or the skin of the mastoid by a metal headband [1]. These devices had limited success due to high attenuation and distortion from intervening soft tissue and did not become more successful until direct transmission to bone via osseointegration was achieved in the 1970s [1–2]. …”