If a peptic ulcer perforates, air will leak from the inside of the gastrointestinal tract (which always contains some air) to the peritoneal cavity (which normally never contains air). This leads to "free gas" within the peritoneal cavity. If the patient stands erect, as when having a chest<unk> -ray, the gas will float to a position underneath the diaphragm. Therefore, gas in the peritoneal cavity, shown on an erect chest<unk> -ray or supine lateral abdominal<unk> -ray, is an omen of perforated peptic ulcer disease.
Peptic ulcer X ray
Peptic ulcer physical examination
Helicobacter pylori infection physical examination
Barrett's esophagus physical examination
Peptic ulcer disease endoscopy
Gastrointestinal varices CT scan
Upper gastrointestinal bleeding CT scan
Upper gastrointestinal bleeding physical examination