Ultrasound contrast plane wave imaging

Area of Science:

• Ultrasound imaging
• Medical physics
• Biomedical engineering

Background:

• Ultrasound monitoring of microbubbles aids molecular and perfusion imaging.
• Conventional ultrasound imaging can destroy microbubbles, limiting imaging duration.
• Microbubble destruction hinders accurate assessment of accumulation and perfusion.

Purpose of the Study:

• To evaluate ultrafast plane wave imaging for microbubble-based ultrasound imaging.
• To compare microbubble preservation and image contrast between plane wave and conventional imaging.
• To assess the potential of plane wave imaging for continuous molecular imaging.

Main Methods:

• Microbubbles imaged in a flow phantom using conventional focused pulses and plane wave imaging.
• Imaging performed at varying peak negative pressures (14–650 kPa) at 7.5 MHz.
• Microbubble disruption quantified by comparing intensity before and after image acquisition.

Main Results:

• Plane wave imaging required 24x higher acoustic intensity to disrupt 50% of microbubbles.
• Both methods achieved similar resolution, but plane wave imaging offered superior contrast.
• Contrast-pulse sequencing with plane waves improved contrast by 11 dB over conventional nonlinear imaging at 50% disruption.

Conclusions:

• Plane wave imaging reduces peak acoustic intensity by spreading energy over more pulses, preserving microbubbles.
• This technique enables continuous monitoring of microbubble accumulation.
• Enhanced contrast and microbubble preservation position plane wave imaging for advanced molecular imaging applications.