An omphalocoele is a congenital midline abdominal wall defect at the base of the umbilical cord insertion. It is typically a large defect through which liver or bowel or both herniate. It is covered by a peritoneal membrane with the umbilical cord inserting at or near its apex. Associated anomalies are common, including chromosomal, CNS, cardiac, genitourinary and gastrointestinal anomalies, which confer a poor prognosis. Syndromes that include omphalocoeles are Beckwith-Wiedemann syndrome, bladder exstrophy and pentalogy of Cantrell. The differential diagnoses are gastroschisis (smaller para-umbilical defect usually to the right of midline, usually containing only bowel loops and not covered by a membrane) and limb-body wall complex (large defect usually to the left of midline).

References:
1. Reuter KL, Babagbemi TK Obstetric and Gynaecological Ultrasound Case Review Series, 2nd edition. Mosby Elsevier 2007
2. Dahnert W. Radiology Review Manual, 5th edition. Lippincott, Williams and Wilkins 2003

Credit: Dr Donna D’Souza
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