Abstract：
OBJECTIVE: To demonstrate the entire course of the human vitelline vein (VV) in specimens after degeneration of the yolk sac.
METHODS: Sagittal and horizontal histological sections from 8 embryos and 19 fetuses (gestational age approximately 6-12 weeks; crown-rump length 11-61 mm) were examined.
RESULTS: Two types of VV remnants were observed: a long VV on the right superior side of the mesentery of the jejunum (VV1) and a short VV on the left inferior side of the mesentery (VV2). The VV1, observed in 12 specimens, was 20-30 microns in diameter and ran dorsally between the right liver lobe and the jejunum, subsequently merging with an initial superior mesenteric vein on the pancreatic head immediately below the superior portion of the duodenum. The VV2, observed in four specimens, passed dorsally between loops of the ileum on the left side of the mesentery of the ileum and connected to the mesentery. Many of the VVs did not originate from the umbilical cord but suddenly started in the sack of physiological herniation. At 10-12 weeks, after herniation, the VVs originated from the umbilicus and were involved by the expanding greater omentum.
CONCLUSIONS: The right-sided and left-sided VVs seemed to correspond to right and left VV remnants, respectively, and both took an upstream course outside the mesentery of the jejunum and ileum. The right VV upstream portion was likely to disappear later than the left one, but the timing of degeneration varied greatly among individuals, depending on the topographical relationship between the right liver lobe and the jejunum.
METHODS: Sagittal and horizontal histological sections from 8 embryos and 19 fetuses (gestational age approximately 6-12 weeks; crown-rump length 11-61 mm) were examined.
RESULTS: Two types of VV remnants were observed: a long VV on the right superior side of the mesentery of the jejunum (VV1) and a short VV on the left inferior side of the mesentery (VV2). The VV1, observed in 12 specimens, was 20-30 microns in diameter and ran dorsally between the right liver lobe and the jejunum, subsequently merging with an initial superior mesenteric vein on the pancreatic head immediately below the superior portion of the duodenum. The VV2, observed in four specimens, passed dorsally between loops of the ileum on the left side of the mesentery of the ileum and connected to the mesentery. Many of the VVs did not originate from the umbilical cord but suddenly started in the sack of physiological herniation. At 10-12 weeks, after herniation, the VVs originated from the umbilicus and were involved by the expanding greater omentum.
CONCLUSIONS: The right-sided and left-sided VVs seemed to correspond to right and left VV remnants, respectively, and both took an upstream course outside the mesentery of the jejunum and ileum. The right VV upstream portion was likely to disappear later than the left one, but the timing of degeneration varied greatly among individuals, depending on the topographical relationship between the right liver lobe and the jejunum.
摘要：
目的：在卵黄囊变性后的标本中显示人卵黄静脉（VV）的整个过程。
方法：检查了8个胚胎和19个胎儿（胎龄约6-12周；冠部长度11-61毫米）的矢状和水平组织学切片。
结果：观察到两种类型的VV残留：空肠肠系膜右上侧长VV（VV1）和肠系膜左下侧短VV（VV2）。在12个样本中观察到的VV1，直径为20-30微米，在右肝叶和空肠之间运行，随后在十二指肠上部正下方的胰头上合并了最初的肠系膜上静脉。在四个样本中观察到的VV2，在回肠肠系膜左侧的回肠环之间背侧通过，并连接到肠系膜。许多VV并非起源于脐带，而是突然开始于生理性疝。在10-12周，疝后,VV起源于脐部，并与扩大的大网膜有关。
结论：右侧和左侧的VV似乎对应于右侧和左侧的VV残留物，分别,两者都在空肠和回肠肠系膜外进行了上游课程。右VV上游部分可能比左VV消失得晚，但是退化的时间在个体之间差异很大，取决于右肝叶和空肠之间的地形关系。
方法：检查了8个胚胎和19个胎儿（胎龄约6-12周；冠部长度11-61毫米）的矢状和水平组织学切片。
结果：观察到两种类型的VV残留：空肠肠系膜右上侧长VV（VV1）和肠系膜左下侧短VV（VV2）。在12个样本中观察到的VV1，直径为20-30微米，在右肝叶和空肠之间运行，随后在十二指肠上部正下方的胰头上合并了最初的肠系膜上静脉。在四个样本中观察到的VV2，在回肠肠系膜左侧的回肠环之间背侧通过，并连接到肠系膜。许多VV并非起源于脐带，而是突然开始于生理性疝。在10-12周，疝后,VV起源于脐部，并与扩大的大网膜有关。
结论：右侧和左侧的VV似乎对应于右侧和左侧的VV残留物，分别,两者都在空肠和回肠肠系膜外进行了上游课程。右VV上游部分可能比左VV消失得晚，但是退化的时间在个体之间差异很大，取决于右肝叶和空肠之间的地形关系。
