Grating Lobe Reduction in Plane-Wave Imaging With Angular Compounding Using Subtraction of Coherent Signals

Area of Science:

• Medical Imaging
• Ultrasound Technology
• Biomedical Engineering

Background:

• Plane-wave imaging (PWI) offers high frame rates but is susceptible to grating lobes with clinical linear arrays.
• Grating lobes in PWI cause image clutter and reduce tissue contrast, hindering diagnostic accuracy.

Purpose of the Study:

• To evaluate null subtraction imaging (NSI) as a method to mitigate grating lobes in PWI.
• To compare NSI's performance against traditional delay and sum (DAS) and generalized coherence factor (GCF) methods.

Main Methods:

• NSI, a nonlinear beamforming technique, was implemented and tested using simulations and physical experiments.
• Imaging performance was assessed using tissue-mimicking phantoms and in vivo rat tumors.
• NSI was compared with DAS (Hann apodization) and GCF for grating lobe reduction and image quality.

Main Results:

• NSI significantly reduced grating lobes compared to DAS and GCF.
• NSI maintained spatial resolution and image contrast effectively.
• The apodization scheme in NSI inherently suppresses grating lobes.

Conclusions:

• NSI offers a novel approach for PWI with multiple steering angles on clinical linear arrays.
• NSI improves image quality by reducing grating lobe artifacts.
• This technique enhances ultrasound imaging capabilities for various applications.