Chen J, Ni C, Zhuang T
Dept. of Biomed. Eng., Shanghai Jiao Tong Univ.
Conf Proc IEEE Eng Med Biol Soc. 2005;2005:7020-3. doi: 10.1109/IEMBS.2005.1616122.
Magnetic resonance elastography (MRE) is a noninvasive technique to measure elasticity of tissues in vivo. For MRE, an additional actuator is needed to be mounted on an observed object, and to excite the object. In this paper, an experiment is set to obtain MR mechanical shear wave images. A novel actuator is proposed to generate mechanical wave propagating inside a gel phantom. The actuator is made of piezoelectric ceramics, and is fixed on a plexiglass bracket. Both of the gel phantom and the actuator are put into a head coil in the scanner's bore. The actuator works synchronously with an imaging sequence running on the scanner. The sequence is modified from a FLASH sequence, into a motion-sensitizing phase-contrast sequence, for shear wave imaging. Wave images are presented to show the effect of those factors, such as the stiffness of the phantoms, the frequency of the actuator, the parameters of the motion-sensitizing gradient, and the oscillation of the patient bed.
磁共振弹性成像（MRE）是一种在体内测量组织弹性的非侵入性技术。对于MRE，需要在观察对象上安装额外的致动器来激发对象。本文进行了一项实验以获取MR机械剪切波图像。提出了一种新型致动器来产生在凝胶体模内传播的机械波。该致动器由压电陶瓷制成，并固定在有机玻璃支架上。凝胶体模和致动器都放入扫描仪孔内的头部线圈中。致动器与扫描仪上运行的成像序列同步工作。该序列从FLASH序列修改为运动敏感相衬序列，用于剪切波成像。给出了波图像以展示诸如体模刚度、致动器频率、运动敏感梯度参数以及病床振荡等因素的影响。
