Newborn with bilious vomiting AXR AP (above) shows a double bubble sign with a dilated stomach to the left of the spine and a dilated duodenum to the right of the spine. Oblique images from an upper GI show a dilated duodenal bulb projecting over the vertebral bodies (lower right) and a small amount of contrast entering the second part of the duodenum (lower left). The diagnosis was duodenal web.