Stand-alone front-end system for high- frequency, high-frame-rate coded excitation ultrasonic imaging

Area of Science:

• Medical Imaging
• Ultrasound Technology
• Biomedical Engineering

Background:

• High-frequency ultrasound imaging is crucial for detailed visualization.
• Achieving a wider dynamic range and higher resolution remains a challenge.
• Coded excitation techniques offer potential improvements in ultrasound system performance.

Purpose of the Study:

• To develop and evaluate a stand-alone front-end system for high-frequency coded excitation imaging.
• To enhance the dynamic range and image quality of ultrasound systems.
• To assess the system's performance in phantom and in vivo studies.

Main Methods:

• Implemented a front-end system with an arbitrary waveform generator and amplifier.
• Utilized 150 MHz sampling rate for waveform digitization and analog conversion.
• Employed 40 MHz lithium niobate transducers for imaging phantoms and biological tissues.
• Evaluated system performance using frame rates up to 68 frames per second.

Main Results:

• Achieved axial resolution of 50 microm and lateral resolution of 120 microm with chirp-coded excitation.
• Demonstrated echo signal-to-noise ratios of 65 dB for coded excitation versus 54 dB for short burst.
• Obtained contrast resolution of 24 dB for chirp-coded excitation and 15 dB for short burst modes.
• Successfully visualized zebrafish and mouse heart structures, including valves and chambers.

Conclusions:

• The implemented system enables high-frequency coded excitation imaging with a wider dynamic range.
• Coded excitation significantly improves resolution and signal-to-noise ratio compared to short burst methods.
• The system demonstrates effective visualization of fine structures in biological tissues, showing promise for advanced ultrasound applications.