PROJECT TITLE :

An ultrasound tomography system with polyvinyl alcohol (PVA) moldings for coupling: in vivo results for 3-D pulse-echo imaging of the female breast

ABSTRACT:

Full-angle spatial compounding (FASC) is a concept for pulse-echo imaging using an ultrasound tomography (UST) system. With FASC, resolution is increased and speckles are suppressed by averaging pulse-echo data from 360°. In vivo investigations have already shown a great potential for 2-D FASC in the feminine breast also for finger-joint imaging. However, providing a small number of pictures of parallel cross-sectional planes with enhanced image quality is not sufficient for diagnosis. So, volume data (three-D) is required. For this purpose, we more developed our UST add-on system to automatically rotate a motorized array (3D probe) around the thing of investigation. Full integration of external motor and ultrasound electronics control in a very custom-created program permits acquisition of three-D pulse-echo RF datasets among 10 min. In case of breast cancer imaging, this concept also enables imaging of close to-thorax tissue regions that can not be achieved by two-D FASC. Furthermore, moldings created of polyvinyl alcohol hydrogel (PVA-H) are developed as a brand new acoustic coupling concept. It encompasses a great potential to switch the water bathtub technique in UST, that could be a vital concept with respect to clinical investigations. In this contribution, we have a tendency to gift in vivo results for 3-D FASC applied to imaging a female breast that has been placed in an exceedingly PVA-H molding during data acquisition. An algorithm is described to compensate time-of-flight and consider refraction at the water-PVA-H molding and molding-tissue interfaces. Thus, the mean speed of sound (SOS) for the breast tissue is estimated with an image-primarily based method. Our results show that the PVA-H molding concept is applicable and feasible and delivers sensible results. three-D FASC is superior to 2-D FASC and provides 3-D volume data at increased image quality.