Figure 1b. CT images in two patients with extrapulmonary injury demonstrate a typical pattern. (a) CT image (at level 3) obtained 5 days after intubation in a patient with ARDS following abdominal surgery shows that IPOd (x) merges with ground-glass opacification (o) in the nondependent lung. (b) CT image (at level 3) obtained in a patient with ARDS secondary to systemic sepsis (day 3 after intubation) shows less-intense parenchymal opacificaton in dependent lung. There is extensive ground-glass opacification and normally aerated lung parenchyma anteriorly.