ABSTRACT
The omphalomesenteric duct or the vitelline duct is a long narrow tube that joins the yolk sac to the digestive tube in the developing human embryo. This duct undergoes complete obliteration during the seventh week in most cases. Development of the midgut in the embryo is characterized by growth and elongation of the gut at the end of the fourth week of gestation. At the apex, the intestinal loop remains connected and open to the yolk sac via the omphalomesenteric duct. Omphalomesenteric remnants can be classified into various types according to the underlying anomaly. The persistent omphalomesenteric duct may remain patent after birth and present as an omphaloileal fistula. The fistula may contain ectopic gastric, colonic, or pancreatic tissue. Affected neonates often present with umbilical discharge, which resembles small bowel content and can result in periumbilical excoriation. For obliterated omphalomesenteric duct, it may persist as a fibrous cord attaching the ileum to the umbilicus internally.
