Time-of-flight completion in ultrasound computed tomography based on the singular value threshold algorithm

Area of Science:

• Medical imaging
• Biomedical engineering
• Diagnostic technology

Background:

• Ultrasound computed tomography (USCT) is used for breast tumor screening.
• Sound-speed imaging in USCT aids tumor diagnosis.
• Missing time-of-flight (TOF) data causes artifacts in USCT images, hindering tumor identification.

Purpose of the Study:

• To address the missing TOF data problem in USCT.
• To improve the accuracy and reduce artifacts in sound-speed reconstructions for better tumor diagnosis.

Main Methods:

• Employed the singular value threshold (SVT) algorithm to complete the TOF matrix.
• Developed a strategy to select the optimal SVT threshold by evaluating image quality.
• Validated the method using numerical breast phantom and in vivo experiments.

Main Results:

• The SVT algorithm successfully eliminated artifacts in reconstructed sound-speed images.
• The method demonstrated higher accuracy compared to existing approaches in numerical experiments.
• In vivo experiments showed improved image sharpness and diagnostic potential for invasive breast cancer.

Conclusions:

• The SVT algorithm effectively completes TOF data, reducing artifacts and enhancing USCT image quality for breast tumor screening.
• The proposed threshold selection strategy shows promise, but requires further research for optimization.
• Future work should focus on refining threshold selection and expanding experimental validation with more USCT cases.