Teenager who was short of breath for a week

CXR and CT of spontaneous pneumothorax due to apical bleb
CXR PA (above left) shows a large amount of air in the right pleural space with some mediastinal shift to the left. There is a round cystic structure in the right lung apex. Coronal (above right) and axial (below) CT without contrast of the chest shows the cystic structure to be a large bleb in the apex of the right lung.

The diagnosis was spontaneous pneumothorax.