Premature newborn with abdominal distension after nasogastric tube placement Supine AXR (above) shows increased lucency in the upper abdomen. The cross-table lateral AXR (below) shows air between the anterior abdominal wall and the bowel. The nasogastric tube follows a very straight course and does not curve towards the stomach. Note on both views that the tip of the nasogastric tube does not project over the stomach. US performed subsequently showed the tip of the nasogastric tube was in the retroperitoneum and not in the stomach. The diagnosis was perforation of the esophagus during nasogastric tube placement. In the operating room the pneumoperitoneum was found to be due to an ileal perforation.