High-field magnetic resonance imaging of the developing human brain from the 10th to the 16th week of gestational age

In the present work, high-field magnetic resonance imaging (HF-MRI) was app lied to study the developing human brain paying particular attention to the structures of interest in pathology of malformation. The aim of the work w as to evaluate the possible application of HF-MRI to the analysis of brain development in the absence of some limits of conventional histological tech nique. Seven formalin-fixed human fetuses of 50, 65, 70, 85, 110, 116 and 1 25 mm crown/ rump length (corresponding to a gestational age ranging from 1 0 to 16 weeks) were examined in an imager-spectrometer equipped with a 4,7- tesla horizontal magnet with a 33-cm bore, In the brain of all the fetuses the telencephalic, mesencephalic and rhombencephalic vesicles were recogniz able and an easy quantitative evaluation of the brain curvatures in the abs ence of distortion due to dissection was possible. Comparing fetuses at dif ferent gestational ages, the spatial modification of the different vesicles was evident. In fetuses at 16 weeks of gestational age, stratified compart ments of the telencephalic wall were evident. The germinal zone and the cor tical plate were visible: the germinal layer was identifiable as a hypointe nsity in the periventricular area. The subplate zone and the intermediate z one emitted a strong intensity signal, Our study demonstrates that HF-MRI c an contribute to the study of the complex developmental events in the human brain from the 10th to 16th week of gestational age in a submillimetric sc ale of resolution. This technique can provide information about the morphol ogy of the encephalic vesicles and their relations with the bone cavity tha t cannot be obtained with conventional methods and may be a useful adjunct to histological techniques.