Higher-order correlation based real-time beamforming in photoacoustic imaging

Area of Science:

• Photoacoustic (PA) imaging
• Medical imaging
• Signal processing

Background:

• Conventional delay-and-sum (DAS) beamformers are suitable for real-time photoacoustic (PA) image formation.
• However, DAS images suffer from noise, sidelobes, and artifacts due to signal correlation inaccuracies.

Purpose of the Study:

• To develop an advanced reconstruction method to mitigate sidelobes and artifacts in PA imaging.
• To enhance overall image quality and imaging performance in real-time PA applications.

Main Methods:

• A novel higher-order delay-multiply-and-sum (DMAS) beamformer was developed, utilizing enhanced signal correlation.
• Algorithms were simplified for real-time implementation, achieving computational complexity similar to DAS (O(N)).
• Validation involved numerical simulations, experimental studies, and GPU-based performance analysis.

Main Results:

• The higher-order DMAS beamformer demonstrated significant improvements in resolution, contrast, and signal-to-noise ratio (SNR) over traditional beamformers.
• Quantitative evaluations confirmed superior performance in SNR, contrast ratio, generalized contrast-to-noise ratio, and FWHM.
• Real-time capability was validated, achieving frame rates comparable to DAS and DMAS.

Conclusions:

• The proposed higher-order DMAS beamformer offers superior PA image reconstruction quality.
• It uniquely enables real-time PA imaging with performance benefits over conventional methods.
• This technique shows significant promise for advancing clinical applications of real-time PA imaging.