用于血管内超声成像的高频换能器研制

血管内超声(Intravascular Ultrasound,IVUS)成像技术可以精确评估血管腔口径、血管壁形态和其他相关血流和血管特性,在冠状动脉疾病的诊断、治疗指导和治疗后的评估中发挥着重要作用。文章设计并制备了一种用于血管内超声成像的高频超声换能器,并对换能器的电学和声学性能进行测试和表征。结果表明,所制备IVUS换能器的中心频率为38.9 MHz,-6 dB相对带宽为56.6%,在谐振频率42.3 MHz处的电阻抗为22.6Ω,在反谐振频率48.2MHz处的电阻抗为56.5Ω,有效机电耦合系数为0.48。使用该换能器进行线仿体成像实验的结果显示,换能器的纵向分辨率为54μm,横向分辨率为209μm。最后,将文中制备的超声换能器与国外同类型换能器进行比较,结果表明,该换能器的性能良好,能够满足血管内超声临床检测需求,未来有望能够突破技术瓶颈,实现国产替代。

Development of a high frequency transducer for intravascular ultrasound imaging

Intravascular ultrasound(IVUS) imaging technology can accurately evaluate vascular lumen diameter,vascular wall morphology, related blood flow and vascular characteristics. It also plays an important role in the diagnosis, treatment guidance and post-treatment evaluation of coronary artery disease. In this paper, a high-frequency ultrasonic transducer for IVUS imaging is designed and fabricated, and the electrical and acoustic performances of the transducer are tested and characterized. The results show that the center frequency of the IVUS transducer is 38.9 MHz, and the-6 dB bandwidth is 56.6%, the resonant frequency is 42.3 MHz at which the electrical impedance is 22.6 Ω; the anti-resonant frequency is 48.2 MHz, at which the electrical impedance is 56.5 Ω; and the effective electromechanical coupling coefficient is 0.48. The results of wire phantom imaging experiments display that the axial and lateral resolutions of the transducer are 54 μm and 209 μm, respectively. Finally, compared with foreign IVUS transducers, the comprehensive results show that the proposed transducer has good performance to meet the needs of clinical diagnose. In the future, the proposed transducer is likely to break through the "bottleneck" technology and achieve domestic replacement.