Ultrafast Imaging of Coherent Plane-wave Compouding Based on a Small Size Ultrasound Transducer / 中国医疗器械杂志

The ultrasound endoscopic probes with very small size transducers are normally imaging by focused ultrasound beamforming technology. So the imaging frame rate is not very high, which cannot meet the needs of some clinical applications based on high imaging rate. In recent years, plane-wave ultrafast imaging technology can obtain high image frame rate and guarantee the image quality. In this paper, a plane wave ultra-fast imaging technique based on a home-made small line array ultrasound transducer is presented. Feasibility of the method is verified by simulation estimations and phantom experiments. The results show that for the small size transducer design of plane wave ultrafast imaging, it is necessary to fully consider the combination of the array element width and the number of array elements. So that a good plane wave imaging quality can be obtained. It lays a foundation for the ultra-fast imaging of plane wave in the interventional ultrasound imaging and ultrasound endoscopy.

Different layer thickness influences of a 50MHz intravascular ultrasound transducer.

In order to design a 50MHz intravascular ultrasound (IVUS) transducer with good pulse-echo responses, in this paper, a finite element model (FEM) was built to simulate the transducer acoustic performances with different layer thicknesses. According to comparisons of the acoustic fields and the admittance curves, the optimum thickness parameters are gained. And then, an IVUS PZT transducer with controlled layer thicknesses was fabricated and tested. The results of pulse-echo response tests shown this transducer with the optimum parameters had very good performance. The central frequency is 45.5MHz and its bandwidth was about 50% which are suitable for intravascular imaging.