A configurable dual-frequency transmit/receive system for acoustic angiography imaging

Acoustic angiography is a high-resolution imaging modality for small vascular structure. It utilizes the nonlinear backscatter of microbubble contrast agents (MCAs) to delineate blood vessels. In acoustic angiography, where MCAs are insonified with high rarefractional pressures at resonance frequency (6.5MHz), high-order harmonics (30 MHz) become more evident and can be utilized to produce high-resolution images for detecting small vascular structures. We developed a configurable dual-frequency system platform dedicated to acoustic angiography. The system consists of pulse generation, data acquisition and signal processing blocks. It is controlled by a field programmable gate array (FPGA), which enables flexible programming, and many on-board processing and stimulation modes. The system was shown to be capable of acoustic angiography as well as traditional B-mode imaging.