There are free air (white arrowhead) and a little ascites (reference mark) in Fig.1-Fig.3. Because no submucosal edema is identified in gastric wall, there seems to be no acute lesion in stomach. Tracking up duodenum from D1 of Fig.8 to cephalad side, it becomes duodenal bulb at D3 of Fig.6. Anterior wall of duodenal bulb presents edematous wall thickening (Fig.5 and Fig.6: black arrowhead). The white arrow indicates duodenal lumen, and black arrow of Fig.5(gas in edematous wall) should be taken to be a wall defect, namely a duodenal ulcer, which leads to a diagnosis of the perforated duodenal ulcer. Because abdominal finding revealed board-like rigidity confined to only epigastrium and ascites is of minimal amount, conservative treatment was chosen with success. Endoscopy 12 days later showed an ulcer of anterior wall of duodenal bulb.

Reference case (non-perforated duodenal ulcer): A 20-year-old male with a past history of duodenal ulcer 3 years ago, had epigastric pain for two weeks. The severe, gradually aggravating epigastric pain occurred 3 hours ago. Temperature: 36.3 degrees Celsius. Examination showed tenderness and rebound tenderness over epigastrium, but without muscle guarding.
There is no free air or ascites. White arrowhead is fatty tissue. Anterior wall of duodenal bulb shows edematous thickening (black arrowhead), and black arrow of Fig.4-Fig.6 should be taken to be gas in acute ulcerative lesion. Symptoms disappeared in one week with conservative treatment.