Newborn with bilious vomiting and a double bubble sign on AXR In the operating room the duodenum was seen to taper between its second and third portions. A nasogastric tube could not be advanced past this area of tapering. There appeared to be a membrane obstructing the duodenum at this point. A duodenotomy was performed which confirmed the presence of a thick membrane completely obstructing the duodenum. Bile was seen above and below this membrane. The bile was coming from one papilla above the membrane and one papilla below it. Surgical image shows the superior retractor distracting the proximal duodenum and the inferior retractor distracting the distal duodenum. The obstructing membrane is seen between the retractors. The obstructing membrane was then incised. The diagnosis was duodenal atresia.