Annular pancreas

Annular pancreas is a rare congenital anomaly where a ring of pancreatic tissue completely or partially encircles the duodenum, often leading to duodenal obstruction. This malformation results from abnormal rotation or fusion of the ventral pancreatic bud during embryonic development.

Assign this code for documented cases of annular pancreas, whether symptomatic or incidentally discovered. It is typically used when imaging studies (e.g., ultrasound, CT, MRI) or surgical findings confirm the presence of pancreatic tissue encircling the duodenum.

• Always confirm the diagnosis with imaging or operative reports.
• Code any associated duodenal obstruction separately, if present and documented.
• Consider sequencing this code as a primary diagnosis if it is the reason for the encounter, or as a secondary diagnosis if it is an incidental finding or contributing factor to another condition.