Preclinical acoustic efficiency evaluation of bionic ear

Abstract

Objective. To study the major acoustic properties of the prototype of bionic ear developed in order to confirm its functional performance.
 Materials and methods. Acoustic properties of the bionic ear were measured using Random Phase MultiSine signal in a test bench, which simulated the implant-emitter-osseous tissue-inner ear system. The resulting pulse response was converted to the target characteristics: FR and group lag. Experiments were carried out for -6dB signal level, 10 times for each of the methods used.
 Results. Microtia is a congenital auricular hypoplasia or aplasia (anotia) which often involves impairment or total loss of hearing. One way to rehabilitate this type of patients is to use bone-conducting apparatuses (bone anchored hearing aids), which allow to compensate for the functional component but not to restore facial aesthetics. This paper deals with major acoustic properties of the prototype bionic ear we have previously developed, in order to confirm its functional performance for clinical use. Our analysis of acoustic characteristics of the bionic ear system showed the frequency response was uniform enough in extended voice frequency range (100 to 10000 Hz). The experimental research demonstrated that operating time of the prototype bionic ear to battery depletion is 10 h 26 min with 25 % amplification, 10 h 05 min with 50 % amplification, 9 h 48 min with 75 % amplification.
 Thus, the acoustic characteristics of the vibratory emitter were determined, which confirmed that the bionic artificial ear was eligible for clinical testing.
 Conclusions. Major frequency response of the vibratory emitter was measured, and confirmed that preclinical studies were successful and the bionic ear was eligible for clinical testing.