Curvilinear 3-D Imaging Using Row-Column-Addressed 2-D Arrays With a Diverging Lens: Feasibility Study

Area of Science:

• Medical Imaging
• Ultrasound Technology
• Array Signal Processing

Background:

• Extending the field-of-view (FOV) in ultrasound imaging is crucial for applications like abdominal and cardiac imaging.
• Current methods often require larger apertures, increasing equipment cost and complexity.
• Double-curved 2-D arrays offer a solution for wider FOV curvilinear imaging without aperture increase.

Purpose of the Study:

• To propose and validate a novel delay-and-sum beamforming scheme tailored for double-curved row-column-addressed (RCA) 2-D arrays.
• To enable 3-D ultrasound imaging with extended FOV using cost-effective equipment.
• To assess the focusing capabilities and imaging quality of these arrays.

Main Methods:

• A specific delay-and-sum beamforming algorithm was developed for double-curved RCA 2-D arrays.
• Simulations were conducted using a synthetic aperture imaging sequence with single element transmissions.
• Imaging quality was evaluated for a 62+62 RCA 2-D array with a diverging lens (f-number -1) at depths up to 14 cm within a 60°×60° curvilinear FOV.

Main Results:

• The proposed beamforming scheme accurately calculates time-of-flight, thereby avoiding geometrical distortions.
• Simulations demonstrated the focusing ability of the double-curved RCA 2-D array.
• The array achieved comparable resolution (Full-Width-at-Half-Maximum) to a flat array within its respective FOV.

Conclusions:

• The developed beamforming approach is effective for double-curved RCA 2-D arrays.
• This method facilitates accurate 3-D imaging with an extended curvilinear field-of-view.
• The findings support the use of double-curved arrays for advanced, cost-efficient ultrasound applications.