快速稳态进动采集序列MR检查在胎儿成像中的应用

Application of MR imaging with fast-imaging employing steady-state acquisition sequence in normal fetus

目的探讨快速稳态进动采集序列(FIESTA)在胎儿MR检查中的应用价值。方法对30例20周以上正常胎儿行MR检查,采用FIESTA序列对胎儿头颅、躯干行轴位、冠状位、矢状位扫描,观察胎儿各系统主要器官,包括脑、肺、心脏、肝、脾、胃肠道等的解剖和MR表现。结果孕20周时,胎儿各主要器官均已发育。中枢神经系统在FIESTA图像脑室系统高信号的衬托下,大脑三层结构清晰可辨,脑室系统呈生理性扩大状态。30周后脑沟、回形成逐渐明显;非神经系统亦可较清晰显示。结论 FIESTA可清楚显示胎儿各主要器官的正常解剖和发育变化,胎儿主要器官和MR表现与新生儿有较大区别。

Objective To investigate the value of MR imaging with fast-imaging employing steady-state acquisition（FIESTA） sequence in normal fetus. Methods Thirty normal fetuses with gestational age greater than 20 weeks underwent MR imaging with FIESTA sequence on sagittal and axial view of the fetus body and the head. The normal fetus anatomy of the brain, lungs, heart, liver, spleen,gastrointestinal tract and their MR manifestations were observed. Reults The main organs of fetus had developed in 20 weeks gestation. In the central nervous system, against the high signal of the ventricular system, three layers of the cerebrum were identified, and the ventricular system was extended physiologically. Cerebral gyri and sulcus developed significantly after 30 weeks gestation. Non-central nervous system（non-CNS） tissues could also be clearly observed. Conclusion FIESTA sequence MR imaging can clearly show the normal fetal anatomy of main organs, which are quite different from those in newborns.