Extended Field of View Imaging Through Correlation With an Experimental Database

Area of Science:

• Medical Imaging
• Ultrasound Technology
• Signal Processing

Background:

• Current ultrasound techniques face limitations in field of view (FOV) and image homogeneity.
• Previous correlation-based (CB) methods utilized numerical reference signals (CB-Num), limiting performance.
• Enhancing image quality and expanding FOV are crucial for diagnostic accuracy.

Purpose of the Study:

• To implement and validate a novel correlation-based (CB) ultrasound imaging technique using experimental reference signals (CB-Exp).
• To extend the field of view (FOV) and improve image homogeneity compared to existing methods.
• To demonstrate the efficacy of CB-Exp in both phantom and in vivo studies.

Main Methods:

• Acquisition, compression, and adaptation of an experimental reference signal database (CB-Exp).
• Utilized backpropagated reflections on point-like scatterers for reference signal generation.
• Validated the technique in vitro using a CIRS 040GSE phantom and in vivo on a piglet's heart.

Main Results:

• CB-Exp achieved a 75° FOV, a significant extension from the 25° FOV achieved with synthetic aperture focusing technique (SAFT).
• Demonstrated a 3.5-dB contrast improvement on the pericardium wall in in vivo piglet heart imaging.
• Reduced background gCNR standard deviation by 0.2 and point-like target level standard deviation by 10 dB, indicating improved homogeneity.

Conclusions:

• The experimental reference signal-based CB ultrasound imaging (CB-Exp) effectively extends FOV and enhances image homogeneity.
• CB-Exp offers superior performance over SAFT and CB-Num, with reduced sensitivity to probe directivity.
• This method provides more uniform sensitivity in axial and lateral directions, leading to higher quality ultrasound images.