A high-frequency, high frame rate duplex ultrasound linear array imaging system for small animal imaging

Area of Science:

• Biomedical Engineering
• Medical Imaging
• Cardiovascular Research

Background:

• High-frequency (HF) ultrasound offers superior spatial resolution for non-invasive imaging in biological research.
• Evaluating mouse heart anatomy and blood flow necessitates real-time B-scan imaging and ultrasound Doppler capabilities.

Purpose of the Study:

• To develop an HF ultrasound duplex imaging system for simultaneous B-mode and Doppler flow measurements.
• To assess the system's performance for in vivo cardiovascular imaging in small animals.

Main Methods:

• Development of a system integrating HF pulsed-wave Doppler and B-mode imaging modules with a 64-element linear array.
• Utilized a 200 MS/s 14-bit A/D card and real-time LabView software for data acquisition.
• Employed 35-MHz and 30-MHz linear arrays with varying pitches for imaging and flow measurements.

Main Results:

• Achieved a 50 dB signal-to-noise ratio (SNR) and >12 mm penetration depth with a 35-MHz array.
• Determined two-way beam widths of 165-260 microm and clutter-to-total-energy ratios (CTR) of 9.1-12 dB.
• Acquired real-time B-mode images at >400 frames per second (fps) with a 30-MHz array.

Conclusions:

• The developed HF ultrasound duplex system enables simultaneous high-resolution anatomical and blood flow imaging of the mouse heart.
• The system demonstrates high frame rates and performance suitable for small animal cardiovascular research.