An Ultrasonic Transceiver for Non-Invasive Intracranial Pressure Sensing.

Area of Science:

• Biomedical Engineering
• Medical Devices
• Ultrasound Technology

Background:

• Intracranial pressure (ICP) monitoring is crucial for diagnosing and managing neurological conditions.
• Current invasive ICP monitoring methods carry risks of infection and complications.
• Non-invasive techniques are highly desirable for continuous and safe ICP assessment.

Purpose of the Study:

• To develop and validate a low-power, portable ultrasonic through-transmission transceiver (TRX) for non-invasive ICP sensing.
• To correlate ultrasonic time-of-flight (ToF) measurements with ICP variations.
• To assess the system's performance against medical-grade invasive ICP sensors.

Main Methods:

• Utilized a 9-mW ultrasonic through-transmission transceiver (TRX) with two transducers at temporal bone windows.
• Measured changes in ultrasonic time-of-flight (ToF) to derive skull expansion and ICP waveform.
• Incorporated a high-efficiency Class-DE power amplifier (PA) and a SAR DLL-based time-to-digital converter (TDC).
• Validated the sensor using water tank and human head phantom setups.

Main Results:

• Achieved high correlation with a medical-grade invasive ICP sensor.
• Demonstrated accurate derivation of ICP waveform from skull expansion.
• The system exhibited high accuracy, low power consumption (9 mW), and reliable performance.

Conclusions:

• The proposed ultrasonic TRX system is a promising solution for real-time, portable, non-invasive ICP monitoring.
• Offers a safe and effective alternative to invasive ICP measurement techniques.
• Suitable for various clinical settings requiring continuous ICP assessment.