Speech quality evaluation of subcutaneously implanted microphone using in vivo experiment

Area of Science:

• Biomedical Engineering
• Audiology
• Acoustics

Background:

• Implantable microphones in fully implantable hearing devices (FIHD) are placed under temporal bone skin.
• Skin implantation causes significant sound attenuation and distortion, especially at high frequencies, impacting speech quality.
• Current implantable microphone assessments lack practical, human auditory-based indicators.

Purpose of the Study:

• To design a subcutaneously implantable microphone for FIHD.
• To investigate the microphone's frequency response via in vivo experiments.
• To evaluate objective speech quality indicators for implanted microphone performance.

Main Methods:

• A subcutaneously implantable microphone was designed and fabricated.
• In vivo experiments were conducted to measure the microphone's frequency response.
• Speech quality indicators were calculated using MATLAB, comparing pre- and post-implantation signals.

Main Results:

• The study successfully designed and tested a subcutaneously implantable microphone.
• In vivo experiments provided data on the microphone's frequency response.
• Objective speech quality indicators were calculated and compared before and after implantation.

Conclusions:

• The developed implantable microphone shows potential for FIHD applications.
• Objective speech quality indicators offer a practical method for evaluating implanted microphone performance.
• Further research is needed to refine these indicators for optimal hearing device design.