Ultrafast 3-D Transcutaneous Super Resolution Ultrasound Using Row-Column Array Specific Coherence-Based Beamforming...

Area of Science:

• Medical Imaging
• Ultrasound Technology
• Biomedical Engineering

Background:

• Traditional 2-D matrix arrays for ultrasound imaging have limitations in channel count and field of view.
• Row-column arrays offer advantages but typically yield poor in vivo image quality, especially for non-invasive applications.
• Improving image quality is crucial for advanced ultrasound techniques like ultrasound localisation microscopy.

Purpose of the Study:

• To develop image formation and post-processing methods for 3-D super-resolution ultrasound imaging using a row-column array.
• To enhance the image quality of row-column arrays for non-invasive imaging applications.
• To demonstrate the feasibility of ultrasound localisation microscopy with a row-column array in vivo.

Main Methods:

• Developed a processing pipeline incorporating rolling window image reconstruction.
• Integrated a row-column array specific coherence-based beamforming with acoustic sub-aperture processing.
• Implemented methods to reduce secondary lobe artifacts and noise, and increase effective frame rate.

Main Results:

• Reduced 'false' locations in vitro from ~26% to ~15% compared to orthogonal plane wave compounding.
• Achieved a noise reduction of ~7 dB and increased effective frame rate to over 4000 fps.
• Successfully produced non-invasive ultrasound localisation microscopy images of a rabbit kidney and a human thyroid in vivo.

Conclusions:

• Demonstrated that proposed methods enable large field of view super-resolution microvascular imaging with a row-column array.
• Confirmed the feasibility of non-invasive in vivo super-resolution ultrasound imaging in both animal models and humans.
• The developed techniques significantly improve the utility of row-column arrays for advanced medical imaging.