Hepatic Embryonic Development and Anomalies of the Liver

Abstract

Hepatic embryonic development occurs in three phases. Competence phase (or pre-pattern phase): where the hepatic diverticulum is seen on the 18th day of gestation as a thickening of the ventral floor of the distal foregut endoderm. Specification phase: specification of the liver gene program within the entoderm by signals from cardiac mesoderm that will, later, later to liver formation. Morphogenesis phase: refers to growth of the hepatic bud in the septum transversum mesenchyme and formation of the liver by integration of the parenchymal cells within the developing vascular system. The origin of the anomalies of hepatic morphology occurring in the course of organogenesis remains to be elucidated. Actually, congenital abnormalities of hepatic morphology, as opposed to anatomical variations, are rare. Nevertheless, knowledge of such anomalies is important since they do not always remain clinically latent. Awareness of these anomalies will decrease morbidity and keep away from a number of medical and surgical pitfalls.