Limited-view scanning microwave-induced thermoacoustic CT using a multi-element linear transducer array

摘要

In this paper, we have developed a limited-view scanning microwave-induced thermoacoustic computed tomography (CT) system based on the multi-element phase-controlled focus technique. A 320-element linear transducer array was relatively rotated to capture thermoacoustic signals within limited detection views, which effectively eliminated the problem that the focused ultrasonic transducer can but receive finite signal from boundaries of tissues which are nearly perpendicular to the axis of the transducer. Using phase-controlled focus technique to collect thermoacoustic signals, the data need not be averaged because of a high signal-to-noise ratio, resulting in a data acquisition time of less than 5 s in each view. The collected limited-view data was utilized to reconstruct the geometrical details based on limited-field-filtered back-projection algorithm. The system may provide a reliable approach to thermoacoustic imaging, which can potentially be developed as a powerful diagnostic tool for early-stage breast caners.