Omphalomesenteric Duct Remnants

The omphalomesenteric (or vitellointestinal) duct is an embryonic communication between the primitive yolk sac and the developing midgut. During normal development at the 6th week of embryogenesis, the midgut loop elongates and herniates into the umbilical cord. Within the ‘physiological umbilical hernia’, the midgut rotates 90° counter clockwise around the axis of the superior mesenteric artery. At the same time, as the midgut elongates the lumen of the omphalomesenteric duct begins a process of obliteration. By the 10th week of early fetal development, the midgut returns to the abdominal cavity and the omphalomesenteric duct becomes a thin fi brous band, which undergoes resorption. Persistence of the duct leads to a spectrum of anomalies that can present clinically in the newborn period, infancy or later childhood years.