Row Transmission for High Volume-Rate Ultrasound Imaging With a Matrix Array

Area of Science:

• Medical Imaging
• Ultrasound Technology
• Biomedical Engineering

Background:

• Standard 1024-element matrix arrays for 3-D ultrasound suffer from blank rows, degrading volumetric image quality.
• These blank rows disrupt elevation periodicity, limiting 3-D spatial resolution and overall image fidelity.

Purpose of the Study:

• To introduce a novel row-transmission (RT) scheme to enhance 3-D ultrasound imaging.
• To improve spatial resolution and overcome limitations caused by blank rows in the elevational direction.
• To maintain azimuthal steering capability while enhancing volumetric image quality.

Main Methods:

• The RT scheme divides the array into four multi-row apertures (MRAs), each transmitting diverging waves (DWs) sequentially.
• It employs coherent DW compounding (CDWC) in azimuth and multielement synthetic aperture (M-SA) imaging in elevation.
• The cascaded synthetic aperture (CaSA) strategy was integrated as RT-CaSA to boost signal-to-noise ratio (SNR).

Main Results:

• Phantom studies showed RT significantly improved lateral resolution compared to conventional Bank-by-bank transmission-reception (Bank) and sparse-random-aperture compounding (SRAC).
• RT-CaSA demonstrated superior contrast ratios (CRs) over Bank and SRAC.
• In vivo human abdominal aorta imaging confirmed RT-CaSA achieved the highest aortic wall motion estimation accuracy.

Conclusions:

• The proposed RT scheme effectively bypasses blank rows, enhancing 3-D ultrasound spatial resolution and image quality.
• RT-CaSA offers significant improvements in contrast and motion estimation accuracy, outperforming existing methods.
• This RT scheme holds considerable potential for advancing various matrix array-based 3-D imaging applications.