Figure 9a. Benign gastric emphysema in an asymptomatic 68-year-old man undergoing high-dose dexamethasone therapy. (a) Abdominal radiograph obtained with the patient upright demonstrates a thin, linear area of increased radiolucency that outlines the gastric wall (arrows). (b) Unenhanced CT scan obtained at the same level helps confirm the presence of a thin, linear distribution of intramural air (arrows). Compare this finding with the nodular appearance of emphysematous gastritis in Figure 8a.