Fiber Bragg Grating Pulse and Systolic Blood Pressure Measurement System Based on Mach-Zehnder Interferometer

Area of Science:

• Biomedical Engineering
• Optical Sensing
• Cardiovascular Monitoring

Background:

• Accurate and continuous blood pressure monitoring is crucial for cardiovascular health management.
• Traditional methods for blood pressure measurement can be invasive or provide only intermittent readings.
• Developing non-invasive, real-time monitoring systems is a key area of medical device research.

Purpose of the Study:

• To propose and validate a novel Fiber Bragg Grating (FBG) based system for simultaneous pulse wave and systolic blood pressure (SBP) measurement.
• To utilize an edge-filtering method with a Mach-Zehnder interferometer (MZI) for precise optical signal processing.
• To assess the system's accuracy and compliance with medical equipment standards for potential clinical application.

Main Methods:

• Development of an edge-filtering system using a Mach-Zehnder interferometer (MZI) with a linear slope of 52.45 dBm/nm.
• Integration of Fiber Bragg Gratings (FBGs) for pulse detection at three radial artery positions (Cun, Guan, Chi).
• Calculation of Systolic Blood Pressure (SBP) based on the Pulse Transit Time (PTT) principle, processed by Field-Programmable Gate Array (FPGA) circuits.

Main Results:

• The system achieved a Mean Absolute Error (MAE) and Standard Deviation (STD) of 0.93 ± 3.13 mmHg when compared to a standard blood pressure monitor.
• Simultaneous measurement of pulse pulsations at three distinct radial artery locations was successfully demonstrated.
• The system met the stringent requirements set by the Association for the Advancement of Medical Instrumentation (AAMI).

Conclusions:

• The proposed FBG edge-filtering system offers a viable method for continuous, real-time, non-invasive monitoring of pulse and SBP.
• The system exhibits fast detection, stable performance, and a comfortable user experience, lacking the compression sensation of traditional devices.
• This technology holds significant potential for applications in human health monitoring and the advancement of medical devices.