Optimal Position and Orientation of an Ossicular Accelerometer for Human Auditory Prostheses.

Area of Science:

• Biomedical Engineering
• Audiology
• Materials Science

Background:

• Current auditory prostheses often rely on external microphones, limiting device integration and patient comfort.
• Totally implantable auditory prostheses require internal sensing components to replace external microphones.
• Piezoelectric accelerometers offer potential for sensing vibrations within the middle ear.

Purpose of the Study:

• To develop a method for optimizing the placement and orientation of an implantable piezoelectric accelerometer on the incus.
• To identify sensor parameters that maximize pressure sensitivity and minimize loudness perception for auditory prostheses.
• To provide guidelines for sensor orientation to improve accelerometer performance in totally implantable devices.

Main Methods:

• A novel method was developed to determine the optimal location and angular orientation of an accelerometer on the incus.
• Optimization criteria included maximizing the sum of pressure sensitivities and minimizing the sum of loudness levels.
• The incudomalleolar joint area was identified as the optimal attachment site.

Main Results:

• The optimal location for the implantable accelerometer was found to be near the incudomalleolar joint.
• Specific angular orientations of the sensor were determined to be critical for performance.
• The proposed method allows for optimization of accelerometer design and performance for auditory applications.

Conclusions:

• A systematic method for optimizing implantable accelerometer placement and orientation on the incus has been established.
• This optimization is crucial for enhancing the performance of totally implantable auditory prostheses.
• The findings provide practical guidelines for the design and integration of accelerometers in future auditory devices.