Umbilical residual

The umbilical ureter is a tubular thin band formed between the umbilicus and the bladder in the early embryo. It gradually closes into fibrous cords during the subsequent embryonic period and infancy, losing its role as an excretory duct and gradually disappearing. However, in about 20% to 30% of adults, a detailed physical examination can find a cord-like or tubular object (called the umbilical ligament) connected subcutaneously to the bladder. The umbilical ureter is an extraperitoneal structure. Generally, an adult umbilical canal is 3 to 10 cm long, 8 to 10 mm in diameter, and the top diameter is about 2 mm. Umbilical ureteral residues usually have no obvious symptoms and signs, but the incidence is still 2 / 300,000 in infants and about 1/5000 in adults; the incidence is about twice that in men. The specific clinical manifestations are related to the type of malformations of the umbilical ureter.