What are the symptoms of a Meckel's diverticulum cyst?

Patient's question:

No

Doctor's answer:

The urachus is a fibrous cord within the loose connective tissue between the umbilicus and the bladder, formed by the degeneration of the allantoic duct during embryonic development. If the urachus does not close after birth, it results in a congenital anomaly. There are four types:
① Urachal fistula, where both ends of the urachus are open, allowing the bladder to communicate with the outside through the urachus. Clinically, this presents as leakage of urine from the umbilicus.
② Closure at the umbilical end and openness at the bladder end, forming a bladder dome diverticulum.
③ Openness at the umbilical end and closure at the bladder end, forming an urachal sinus. Clinically, this presents as mucoid or purulent discharge from the umbilicus.
④ Closure at both ends with an open middle section, forming an urachal cyst. The latter two, if the lumen is large, may present with a palpable mass between the umbilicus and bladder in the abdominal wall, accompanied by pain or tenderness. This case belongs to the fourth type, with the following ultrasound findings: a in the abdominal wall, thick walls, convex toward the peritoneal cavity, and moving in sync with the abdominal wall during respiration but showing relative motion with the intestines. Ultrasound examination shows a tubular or cystic image between the umbilicus and the pubic symphysis in the abdominal wall, highly suggestive of an open urachus (as shown in the figure). Differential diagnoses include:
① Abdominal hernia: The imaging is similar to the above, but the hernia can be reduced into the abdominal cavity, whereas the urachal cyst cannot.
② Ovarian cyst or mesenteric cyst: Both are located in the abdominal cavity and show relative motion with the abdominal wall during respiration, with most being mobile.
③ Tuberculous peritonitis: Most cases have cystic fluid or effusion in the abdominal cavity, accompanied by tuberculosis symptoms.
④ Sebaceous cyst: It does not communicate with the umbilicus, but the urachal cyst does.