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Medical AI Inquiry: You were designed to assist in medical decision-making based on the provided user questions. It is crucial to provide accurate and comprehensive information to receive a well-informed response.
user
A 4-year-old male child is admitted to the hospital with severe vomiting. Radiographic examination and history taking reveals that the boy suffers from an annular pancreas. Which of the following structures is most typically obstructed by this condition?
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The correct answer is  In normal pancreatic development a bifid ventral pancreatic bud rotates around the dorsal side of the gut tube and fuses with the dorsal pancreatic bud. Rarely, a portion of the ventral bud rotates around the ventral side of the gut tube, resulting in an annular pancreas. The portion of the gut tube is the same where the main pancreatic duct enters the second part of the duodenum (along with the common bile duct). The incidence of annular pancreas is about 1 in 7000.