Frijlink Martijn E, Goertz David E, Vos Hendrik J, Tesselaar Erik, Blacquière Gerrit, Gisolf Andries, Krams Rob, van der Steen Antonius F W
Biomedical Engineering, Erasmus MC, University Medical Center Rotterdam, Rotterdam, The Netherlands.
Ultrasound Med Biol. 2006 Nov;32(11):1649-54. doi: 10.1016/j.ultrasmedbio.2006.05.024.
Recent studies have shown the feasibility of tissue and contrast harmonic imaging with a prototype nonlinear intravascular ultrasound (IVUS) system using a conventional single-element rotating IVUS catheter. In this study, a dual-frequency transducer element was mounted in an IVUS catheter and its second harmonic imaging performance was investigated and compared with that of a conventional IVUS catheter. Hydrophone measurements showed a transmit efficiency improvement of >6 dB for the dual-frequency catheter at 20 MHz. In vitro phantom experiments showed a signal-to noise ratio improvement of >5 dB in second harmonic mode at 40 MHz (H40) with the dual-frequency catheter, when using equal transmit voltage for both catheters. Finally, in vivo experiments were conducted and showed image improvement in H40 acquisitions with respect to the conventional IVUS catheter.
近期研究表明，使用传统单元素旋转式血管内超声（IVUS）导管的原型非线性血管内超声系统进行组织和对比谐波成像具有可行性。在本研究中，将双频换能器元件安装在IVUS导管中，并对其二次谐波成像性能进行了研究，并与传统IVUS导管的性能进行了比较。水听器测量结果显示，双频导管在20 MHz时的发射效率提高了>6 dB。体外模型实验表明，当两个导管使用相同的发射电压时，双频导管在40 MHz（H40）的二次谐波模式下的信噪比提高了>5 dB。最后，进行了体内实验，结果表明与传统IVUS导管相比，H40采集的图像有所改善。
