Q: In normal circumstances ultrasound is an excellent modality to diagnose pneumothorax at bedside. Studies have shown it to be superior to chest X-ray for diagnosis of pneumothorax in experienced hands. In which ondition, ultrasound can be deceiving and should be use with clinical picture and in combination of other modality for diagnosis of pneumothorax?


Answer:  COPD

Emphysematous lungs may mimic a pneumothorax. Caution should be exercised before embarking onto adventure of putting chest tube.



Reference: 

 Slater A, Goodwin M, Anderson KE, Gleeson FV. COPD can mimic the appearance of pneumothorax on thoracic ultrasound. Chest 2006; 129:545.