Short-lag spatial coherence imaging on matrix arrays, part 1: Beamforming methods and simulation studies

Area of Science:

• Ultrasound imaging
• Medical imaging
• Signal processing

Background:

• Short-lag spatial coherence (SLSC) imaging improves ultrasound performance over conventional B-mode.
• Current SLSC imaging is limited to 1-D arrays, restricting its dimensional capabilities.
• Extending SLSC to 2-D arrays is crucial for advanced volumetric imaging.

Purpose of the Study:

• To extend the Short-lag spatial coherence (SLSC) imaging algorithm for 2-D matrix array transducers.
• To evaluate the impact of subaperture configuration and channel noise on SLSC imaging performance.
• To assess the feasibility of volumetric SLSC imaging with existing 2-D arrays.

Main Methods:

• Developed and applied an extended SLSC algorithm for 2-D matrix arrays.
• Conducted simulation studies to analyze imaging performance under varying conditions.
• Investigated the effects of subaperture size and shape on contrast-to-noise ratio (CNR) and signal-to-noise ratio (SNR).

Main Results:

• 2-D SLSC imaging significantly outperformed 1-D SLSC and B-mode imaging in CNR and texture SNR.
• Square subapertures yielded better results than 1-D subapertures of equal area.
• Subaperture beamforming showed minimal impact on SLSC performance for subapertures up to 8x8 elements.
• Utilizing 8x8, 4x4, and 2x2 subapertures improved channel SNR by 8x, 4x, and 2x, respectively, with substantial reductions in computation time.

Conclusions:

• Volumetric SLSC imaging is feasible and offers significant advantages over conventional methods.
• The extended SLSC algorithm is compatible with existing 2-D arrays and subaperture beamforming techniques.
• SLSC imaging provides a powerful tool for enhanced ultrasound diagnostics.