The Chest X-ray in Other Common Conditions

In terms of the chest x-ray in other common conditions:

Chronic obstructive pulmonary disease (COPD)

The chest x-ray may be normal, or show hyperinflation with flattening of the diaphragm and a vertically elongated heart. Bullae may be seen as black areas devoid of lung markings – these can occasionally be mistaken for pneumothoraces.

Fig 1: Emphysema (COPD)	Fig 2: Bullae

Pulmonary embolus

Most commonly the x-ray will be normal. Rarely a wedge shaped peripheral infarct, paucity of peripheral vessels, a small effusion or linear atelectasis may be picked up.

Pneumothorax

Air in the pleural space. The lung edge is visible with absent lung markings outside it. Tracheal deviation or shift of the mediastinum denotes a tension pneumothorax. Can be spontaneous, iatrogenic or traumatic.

Fig 3: Left pneumothorax	Fig 4: Right pneumothorax

Other possibilities

Other possibilities could be, for example, a bulla or a skin fold.

Fig 5: Large mistaken pneumothorax (bulla)	Fig 6: Small mistaken pneumothorax (skin fold – arrow)

Learning bite

The medial border of the scapula, lung bullae, air outside the chest in skin folds and the reservoir bag of the oxygen mask have all been mistaken for lung edges. Before diagnosing a pneumothorax, stop and consider the other possibilities.