A dynamic generalized coherence factor for side lobe suppression in ultrasound imaging

Area of Science:

• Medical Imaging
• Ultrasound Technology
• Signal Processing

Background:

• Coherence-based weighting techniques are crucial for enhancing ultrasound image quality.
• Generalized coherence factor (GCF) improves robustness but has limitations in side lobe suppression due to a constant cut-off frequency.
• Existing methods struggle to balance speckle preservation with artifact reduction.

Purpose of the Study:

• To introduce a novel dynamic generalized coherence factor method (DGCF-C) for improved ultrasound image quality.
• To address the limitations of constant cut-off frequencies in GCF methods.
• To enhance resolution, contrast, and speckle preservation in ultrasound images.

Main Methods:

• Developed a dynamic GCF (DGCF-C) method utilizing amplitude standard deviation and convolution output of aperture data.
• Implemented adaptive selection of the cut-off frequency for GCF at each imaging point.
• Evaluated the method through simulations and tissue-mimicking phantom studies.

Main Results:

• DGCF-C (Mmax=2) demonstrated significant resolution improvements: 35.1% in simulation and 32.6% in experiments compared to GCF (M0=1).
• DGCF-C (Mmax=4) showed superior performance over GCF (M0=2), with average improvements of 13.5% in generalized contrast-to-noise ratio (GCNR) and 15.2% in speckle signal-to-noise ratio (sSNR).
• The proposed method effectively preserves speckle patterns while improving image quality metrics.

Conclusions:

• The dynamic GCF-C method offers substantial improvements in ultrasound image resolution and contrast.
• DGCF-C effectively overcomes the side lobe suppression limitations of traditional GCF methods.
• This technique provides a robust approach for enhancing ultrasound image quality and diagnostic accuracy.