Cochlear Optical Sensor for Implantable Microphone Noise Reduction
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Implantable microphones face performance degradation due to skin attenuation and resonance frequency shift, leading to reduced bandwidth and increased noise sensitivity from body-induced vibrations, and require complex surgery for middle ear sensor fixation.
Innovation Solution
A stimulation assembly with an optical sensor configured to measure pressure within the cochlea, using a light source, waveguide, and detector to convert pressure variations into electrical signals, integrated with electrodes for implantable microphone functionality and surgical guidance.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If a subcutaneous microphone is used with a diaphragm covered by skin tissue, then the device can be fully implantable and waterproof, but the skin layer attenuates external sound and shifts resonance frequency, reducing microphone performance and bandwidth
Solution Approach 1:
The patent introduces an intermediary cavity filled with acoustic coupling fluid between the external environment and the diaphragm. This fluid-filled cavity acts as a mediator that transmits sound waves to the diaphragm without requiring direct contact with skin tissue, thereby eliminating skin attenuation and resonance frequency shift while maintaining the fully implantable configuration.
Solution Approach 2:
The patent replaces the traditional direct mechanical coupling of the diaphragm to the external environment with an optical sensing system. The optical sensor detects sound waves through the acoustic coupling fluid without mechanical contact with skin, substituting the mechanical transmission path with an optical one that avoids skin-induced performance degradation.
2Measurement precision
If vibration sensors are mounted to the ossicles in the middle ear, then sound information can be extracted from the natural auditory pathway with improved signal-to-noise ratio, but more complex surgery is required for sensor fixation
Solution Approach 1:
The patent extracts the sound detection function from the middle ear ossicles and relocates it to the cochlea. By placing the optical sensor directly in the cochlear fluid, the system eliminates the need for complex middle ear surgery while still accessing the auditory pathway through the natural cochlear structure, thereby reducing surgical complexity while maintaining measurement precision.
3Reliability
If the diaphragm is mass loaded under skin tissue, then the device can be fully implantable, but body-induced vibrations from chewing, breathing, and speaking increase noise sensitivity
Solution Approach 1:
The acoustic coupling fluid serves as an intermediary that decouples the diaphragm from direct contact with skin and bone. This fluid medium transmits sound waves while isolating the diaphragm from body-induced vibrations, thereby reducing noise sensitivity while maintaining full implantability.
Solution Approach 2:
The patent replaces the mechanical diaphragm system that is directly exposed to body vibrations with an optical sensing system. The optical sensor detects sound waves through the acoustic coupling fluid without being mechanically coupled to skin or bone, thereby eliminating sensitivity to body-induced vibrations while maintaining the fully implantable configuration.
Applied Scientific Principles
This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.
Function Achieved in This Case
Enhances sound detection fidelity by minimizing noise interference and reducing surgical complexity through real-time pressure monitoring during implantation, improving signal-to-noise ratio and cochlear protection.
Implementation Method 1
an optical sensor that converts variations in light intensity to electrical signals in response to pressure variations in the perilymph
Implementation Method 2
a waveguide member for propagating emitted light to the optical sensor
Data Source
AI summary
The present application discloses a hearing prosthesis comprising a stimulation assembly configured to be implanted into a cochlea. The stimulation assembly comprises a plurality of electrodes and one or more sensors. The one or more sensors may be configured to measure pressure within the cochlea. The pressure measurements may include (i) measurements of pressure corresponding to a physical contact of the one or more sensors with internal cochlear structures, (ii) measurements of perilymph fluid pressure, or (iii) measurements of pressure waves in the perilymph fluid corresponding to external sound waves. In one aspect, the sensor may be used by a system to help surgeons avoid damage to the cochlea during surgical implantation of the stimulation assembly. In another aspect, the sensor may be one component of an implantable microphone.