Annular pancreas: Radiological features of a rare case of infantile vomiting

Our purpose is to illustrate the radiological aspects of the annular pancreas as an etiology of duodenal obstruction in infants. We report the case of a 4-month-old girl, who was admitted to our department with postprandial vomiting evolving since birth. The initial examination found a severely dehydrated patient. Abdominal ultrasound showed gross dilatation of the stomach and duodenum, it also showed pancreatic tissue surrounding the duodenum, suggesting a diagnosis of annular pancreas as the cause of the duodenal obstruction. Post-contrast abdominal CT showed the gastric and duodenal dilatation, and a ring of pancreatic tissue surrounding uncompletly the second portion of the duodenum. The patient underwent a bypass surgery which consisted in a duodeno-duodenostomy with simple post-operative follow-up and no recurrence of digestive symptoms. Annular pancreas is a rare pathology to be sought in neonatal obstruction. A good knowledge of radiological semiology is essential for a good diagnostic approach. However, surgery is the only effective way to diagnose and treat this pathology.