Brisse H, Fallet C, Sebag G, Nessmann C, Blot P, Hassan M
Service de Radiopédiatrie, Hôpital Robert Debré, Paris, France.
AJNR Am J Neuroradiol. 1997 Sep;18(8):1491-7.
To assess the in vitro MR signal of the developing brain through histologic comparisons.
Five healthy fetal specimens aged 16, 19, 22, 27, and 34 gestational weeks were studied in vitro using T1- and T2-weighted sequences in frontal and axial planes. Neuropathologic studies included sections in the same frontal plane. Comparison of histologic sections with measurements of the relative widths of the layers of different signal intensities enabled us to assign cellular correspondence to each MR layer.
In the cerebral mantle, a layered pattern was observed on both T1- and T2-weighted images. In the basal ganglia, signal from the pallidum and thalamus was isointense with white matter from 16 to 22 weeks' gestation; then, from 27 and 34 weeks' gestation, the signal was relatively high on T1-weighted images and low on T2-weighted images. The neostriatum had a relatively low signal on T1-weighted images and a high signal on T2-weighted images from 16 to 27 weeks' gestation: then, at 34 weeks' gestation, the signal was relatively high on T1-weighted images and low on T2-weighted images.
MR imaging can clearly show specific patterns of growing fetal brain in vitro.
通过组织学比较评估发育中大脑的体外磁共振（MR）信号。
对5例分别处于孕16、19、22、27和34周的健康胎儿标本进行体外研究，采用额面和轴面的T1加权及T2加权序列成像。神经病理学研究包括相同额面的切片。通过将组织学切片与不同信号强度层的相对宽度测量值进行比较，我们能够确定每个MR层对应的细胞结构。
在大脑皮质，T1加权和T2加权图像上均观察到分层模式。在基底神经节，苍白球和丘脑的信号在孕16至22周时与白质等信号；然后，在孕27至34周时，T1加权图像上信号相对较高，T2加权图像上信号相对较低。在孕16至27周时，新纹状体在T1加权图像上信号相对较低，在T2加权图像上信号较高；然后，在孕34周时，T1加权图像上信号相对较高，T2加权图像上信号相对较低。
MR成像能够在体外清晰显示发育中胎儿脑的特定模式。
