Shen Shu-Huei, Guo Wan-Yuo, Hung Jeng-Hsiu
Department of Radiology, Taipei Veterans General Hospital and National Yang-Ming University, Taiwan, R.O.C.
J Magn Reson Imaging. 2007 Sep;26(3):672-7. doi: 10.1002/jmri.21054.
To evaluate the value of two-dimensional fast imaging employing steady-state acquisition (2D FIESTA) cine MR with parallel imaging techniques in the diagnosis of fetal non-central nervous system (CNS) anomalies.
A total of 28 pregnant women were referred for further MR evaluation on fetuses after abnormal sonographic results. A total of 33 fetal MR examinations were performed by a 1.5 T MR scanner with eight-channel phase-arrayed body coils. Single-shot fast spin-echo (SSFSE(R), GE) of three orthogonal planes and 2D FIESTA for cine fetal MR of three sagittal planes (midsagittal and 10 mm off midline on left and right) were routinely acquired. Additional planes on target organs with variable imaging frames were added if indicated.
Nine of the 33 examinations (9/33; 27.3%) had motion artifacts obscuring the detail in SSFSE imaging; 2D FIESTA imaging provided motion-artifact-free imaging in all of them. Cine 2D FIESTA imaging provided additional information on the visceral peristalsis. The information helped in differentiating dilated gastrointestinal (GI) tract from other intraabdominal cystic lesions and in confirming the nature and level of GI tract obstruction.
With sub-half-second temporal resolution of the 2D FIESTA sequences, fetal movement is no longer problematic. In addition to the anatomical information also provided by conventional SSFSE sequences, 2D FIESTA demonstrates information on motility and peristalsis of hollow organs and helps the diagnosis of fetal visceral anomalies.
评估采用稳态采集的二维快速成像(2D FIESTA)电影磁共振成像(cine MR)结合并行成像技术在胎儿非中枢神经系统(CNS)异常诊断中的价值。
共有28名孕妇在超声检查结果异常后转诊进行胎儿磁共振成像进一步评估。使用配备八通道相控阵体线圈的1.5 T磁共振扫描仪对33例胎儿进行磁共振检查。常规采集三个正交平面的单次激发快速自旋回波(SSFSE(R),GE)序列以及三个矢状平面(正中矢状面和左右偏离中线10 mm)的胎儿电影磁共振成像的2D FIESTA序列。如有需要,可在目标器官上增加具有可变成像帧数的额外平面。
33例检查中有9例(9/33;27.3%)在SSFSE成像中出现运动伪影,掩盖了细节;而2D FIESTA成像在所有这些病例中均提供了无运动伪影的图像。电影2D FIESTA成像提供了关于内脏蠕动的额外信息。这些信息有助于区分扩张的胃肠道(GI)与其他腹腔内囊性病变,并有助于确定胃肠道梗阻的性质和水平。
2D FIESTA序列具有亚半秒的时间分辨率,胎儿运动不再是问题。除了传统SSFSE序列提供的解剖学信息外,2D FIESTA还能显示中空器官的运动性和蠕动信息,有助于胎儿内脏异常的诊断。