Demonstration Study of Reflector-Based Volumetric Speed-of-Sound Imaging With Linear Ultrasound Arrays

Area of Science:

• Biomedical Engineering
• Medical Imaging
• Acoustics

Background:

• Conventional B-mode ultrasound struggles with homogeneous soft tissues due to similar acoustic impedances.
• Speed-of-sound (SoS) imaging offers quantitative biomechanical property assessment for tissue differentiation.
• Three-dimensional (3D) SoS imaging provides detailed morphological data but typically requires specialized ring transducers.

Purpose of the Study:

• To develop and validate a 3D SoS reconstruction system using accessible hand-held linear arrays.
• To overcome limitations of traditional 3D SoS imaging, enabling broader clinical application.
• To assess the system's potential for differentiating tissues and aiding in disease diagnosis, including breast cancer.

Main Methods:

• A novel 3D SoS system was designed using hand-held linear arrays and a passive reflector for time-of-flight (ToF) measurements.
• A high-definition camera was integrated for precise tracking of transducer positions.
• A voxel-based reconstruction algorithm was implemented to merge ToF data and positional information.

Main Results:

• The proposed system demonstrated stable performance in experimental reconstructions using gelatin phantoms and ex vivo tissues.
• The method successfully generated 3D volumetric SoS images with enhanced detail.
• Results indicate the system's capability for accurate quantitative ultrasound imaging.

Conclusions:

• The developed 3D SoS system utilizing hand-held linear arrays is a stable and promising imaging modality.
• This approach offers a more accessible alternative to ring transducer systems for 3D SoS imaging.
• The system shows significant potential as a complementary diagnostic tool for various medical conditions, including breast cancer detection.