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Published on: August 27, 2021
Development of a small wireless position sensor for medical capsule devices
1Department of Electrical Engineering & Bioscience, Waseda University, Tokyo, Japan.
Summary
This study introduces a novel wireless position sensor for tracking medical capsule devices, like video capsule endoscopes, within the digestive tract using mutual induction. The developed sensor achieved accurate positioning up to 500mm with 5mm precision.
Area of Science:
- Biomedical Engineering
- Medical Devices
- Sensor Technology
Background:
- Medical capsule devices, including video capsule endoscopes, are increasingly utilized in clinical settings.
- Current methods for tracking capsule position within the digestive tract are not yet established, posing a clinical challenge.
Purpose of the Study:
- To develop a compact, wireless position sensor for accurately measuring the location of medical capsules in the digestive tract.
- To utilize the principle of mutual induction for non-invasive capsule localization.
Main Methods:
- A wireless position sensor prototype was designed based on mutual induction.
- Primary coil currents were adjusted to maintain constant induced electromotive force in secondary coils.
- Induced electromotive forces were modulated to FM signals, transmitted through tissue, and demodulated externally.
Main Results:
- The prototype sensor demonstrated accurate measurement of capsule position up to 500 mm from primary coils.
- The achieved accuracy for capsule positioning was within 5 mm.
- In vitro evaluation confirmed the sensor's functionality.
Conclusions:
- A novel wireless position sensor for medical capsules has been successfully developed and validated in vitro.
- The sensor utilizes mutual induction for accurate, non-invasive capsule localization.
- Further miniaturization is required for the commercial viability of this capsule position-sensing technology.
