2-yr-old boy with delayed bronchostenosis after recent blunt chest trauma. Contrast-enhanced chest CT scan (3-mm-collimation) obtained 15 days after blunt chest trauma shows left upper lobe atelectasis. Note complete luminal obliteration of the proximal portion of the left upper lobe bronchus (arrowheads). Also note cavitary consolidations in the right upper lobe, suggestive of resolving traumatic lung cysts (arrows).