[Frontiers in Bioscience E2, 231-240, January 1, 2010]

PE-CMOS based C-scan ultrasound for foreign object detection in soft tissue

Chu-Chuan Liu1, 2, Shih-Chung Ben Lo1, Matthew T Freedman1, Marvin E Lasser3, John Kula3, Anita Sarcone1, Yue Wang2

1Imaging Science and Information Systems Center, Georgetown University Medical Center, Washington, DC 20057, USA, 2 Bradley Department of Electrical and Computer Engineering, Virginia Polytechnic Institute and State University, Arlington, VA 22203, USA, 3 Imperium Inc., Silver Spring, MD 20903, USA


1. Abstract
2. Introduction
3. Material and methods
3.1. PE-CMOS sensor array
3.2. Compound acoustic lens system
3.3. Concept of the ultrasound C-scan imaging
3.4. Soft tissue and foreign objects
3.5. Imaging orientation
4. Results
4.1. C-scan ultrasound images
4.2. B-scan ultrasound images
4.3. Film-based radiograph and computerized radiography (CR) image
4.4. Visual comparison of C-scan images and radiographs
4.5. Contrast-to-noise ratio analyses
5. Discussion and conclusions
6. Acknowledgement
7. References


In this paper, we introduce a C-scan ultrasound prototype and three imaging modalities for the detection of foreign objects inserted in porcine soft tissue. The object materials include bamboo, plastics, glass and aluminum alloys. The images of foreign objects were acquired using the C-scan ultrasound, a portable B-scan ultrasound, film-based radiography, and computerized radiography. The C-scan ultrasound consists of a plane wave transducer, a compound acoustic lens system, and a newly developed ultrasound sensor array based on the complementary metal-oxide semiconductor coated with piezoelectric material (PE-CMOS). The contrast-to-noise ratio (CNR) of the images were analyzed to quantitatively evaluate the detectability using different imaging modalities. The experimental results indicate that the C-scan prototype has better CNR values in 4 out of 7 objects than other modalities. Specifically, the C-scan prototype provides more detail information of the soft tissues without the speckle artifacts that are commonly seen with conventional B-scan ultrasound, and has the same orientation as the standard radiographs but without ionizing radiation.