Hansen P E, Ballesteros M C, Soila K, Garcia L, Howard J M
Department of Diagnostic Radiology, Mount Sinai Medical Center, Miami Beach, Fla. 33140.
Radiographics. 1993 Jan;13(1):21-36. doi: 10.1148/radiographics.13.1.8426929.
To establish a baseline of the magnetic resonance (MR) imaging appearance of the fetal brain in early stages of development, the authors undertook a study of fixed and fresh specimens of embryos and fetuses of 6-28 weeks gestational age. Images of formalin-preserved and fresh specimens were comparable in their depiction of anatomic structures. On MR images of embryos of 6 weeks gestational age, the rhombic and cervical flexures, aqueduct of Sylvius, diencephalon, cerebellum, cerebral hemisphere, and fourth ventricle could be differentiated. The optic recess and chiasm, pituitary gland, pineal recess, third ventricle, pons, olfactory lobe, corpus striatum, insula, and parietal and temporal lobes could be distinguished as early as 11 weeks gestation. Although MR imaging is impractical as a screening tool for intrauterine abnormalities, it can demonstrate the fetus in great detail and allows a more specific evaluation of fetal anatomy. With the information provided by MR imaging, it may be possible to establish guidelines for assessment of the stage of development during intrauterine life.
为了建立胎儿大脑发育早期磁共振（MR）成像表现的基线，作者对妊娠6 - 28周的胚胎和胎儿的固定及新鲜标本进行了研究。福尔马林固定标本和新鲜标本的图像在解剖结构描绘方面具有可比性。在妊娠6周胚胎的MR图像上，可以区分菱形和颈曲、中脑导水管、间脑、小脑、大脑半球和第四脑室。早在妊娠11周时就能分辨出视隐窝和视交叉、垂体、松果体隐窝、第三脑室、脑桥、嗅叶、纹状体、岛叶以及顶叶和颞叶。尽管MR成像作为宫内异常的筛查工具并不实用，但它可以非常详细地显示胎儿，并能对胎儿解剖结构进行更具体的评估。借助MR成像提供的信息，有可能建立宫内生命发育阶段评估的指导原则。
