The morphological and histological changes of the choroid plexus (CP) during Carnegie stage (CS) 18 and CS23 were presented, based on magnetic resonance imaging data and histological serial section of human embryos from the Kyoto Collection of Human Embryos. The primordium of the CP was initially detected as a small lump at CS19 that grew caudally, so that the CP became crescent shaped. It developed in all directions after CS21, as the dorsal and frontal growth also became prominent. The CP formed a number of undulating surfaces at CS20, irregular bulges at CS21, and then three large clusters with two deep fissures on the caudal surface at CS23. The mean volume of the CP was 0.282±0.141 mm3 at CS19; it reached 16.8±8.77 mm3 at CS23. Additionally, the histology was different depending on the regions of the CP at all stages after CS20. The epithelium and angioblasts in the center of the stroma were proliferated in the proximal region, whereas the epithelium was differentiated and lobulated in the distal region where the blood vascular system was organized. The histological differentiation was mapped on the CP reconstructed from histological serial sections. The data suggested the correlation between morphological information obtained from magnetic resonance data sets and distribution of the differentiation. With the help of morphological analysis and histological findings, we have been able to categorize each CP into specific stages. These findings will be useful in clinical evaluation of development during the embryonic period.
ヒトの肝臓の形態形成についての論文 (Hirose et al) がAnatomical Recordsの Highlights記事で紹介されました.
AR Highlights
Embryonic Liver Morphology and Morphometry by Magnetic Resonance Microscopic Imaging by Ayumi Hirose, Takashi Nakashima, Shigehito Yamada, Chigako Uwabe, Katsumi Kose, and Tetsuya Takakuwa. Anat Rec 295:51–59
The liver plays an important role in the development of organs in the prenatal period. However, morphological and morphometric features of the liver during the early embryonic period are not well understood. Recent advances in medical imaging have enabled earlier assessment of human development in the first trimester. The authors carried out external morphologic and morphometric analysis of the liver during this period using a superparallel magnetic resonance microscope to image embryos obtained from the Kyoto Collection. They determined the external morphology as well as quantitative morphometry of the embryonic liver. They also found that development of the liver was greatly affected by adjacent organs and tissues. The data from this study provide a better understanding of liver development as well as morphogenesis of nearby organs. The authors’ results could also be used as a reference for clinical evaluation in the early stage of gestation, and this could be useful in fetal medicine and prenatal diagnosis. The authors predict that further improvement in imaging modalities will enable more precise detection of the intrahepatic vascular system.
5.Hamabe Y, Hirose A, Yamada S, Takakuwa T et al, Morphology and Morphometry of Fetal Liver at 16–26 Weeks of Gestation by Magnetic Resonance Imaging – Comparison with Embryonic Liver at Carnegie Stage 23, Hepatol Res,2013; 43: 639–647, doi: 10.1111/hepr.12000
Abstract
Aim
Normal liver growth was described morphologically and morphometrically using magnetic resonance imaging (MRI) data of human fetuses, and compared with embryonic liver to establish a normal reference chart for clinical use.
Methods
MRI images from 21 fetuses at 16–26 weeks of gestation and eight embryos at Carnegie stage (CS)23 were investigated in the present study. Using the image data, the morphology of the liver as well as its adjacent organs was extracted and reconstructed three-dimensionally. Morphometry of fetal liver growth was performed using simple regression analysis.
Results
The fundamental morphology was similar in all cases of the fetal livers examined. The liver tended to grow along the transversal axis. The four lobes were clearly recognizable in the fetal liver but not in the embryonic liver. The length of the liver along the three axes, liver volume and four lobes correlated with the bodyweight (BW). The morphogenesis of the fetal liver on the dorsal and caudal sides was affected by the growth of the abdominal organs, such as the stomach, duodenum and spleen, and retroperitoneal organs, such as the right adrenal gland and right kidney. The main blood vessels such as inferior vena cava, portal vein and umbilical vein made a groove on the surface of the liver. Morphology of the fetal liver was different from that of the embryonic liver at CS23.
Conclusion
The present data will be useful for evaluating the development of the fetal liver and the adjacent organs that affect its morphology.
4. Shiraishi N, Yamada S, Takakuwa T. Three-dimensional Models Once Again – for research and teaching of early human development, Congenit Anom (Kyoto), 2013; 53(1), 58-59, doi: 10.1002/ar.22662
Shiraishi N, Yamada S, Takakuwa T. Three-dimensional Models Once Again – for research and teaching of early human development, congenital anomaly, in press