A pustulothorax is an infection in which the pleural cavity is invaded by pathogenic bacteria and pus accumulates. The vast majority of chronic pus chests are transformed from acute pus chests. The main causes of chronic abscess chest are: (1) acute abscess chest without timely treatment or improper treatment; (2) abscess chest combined with bronchopleural fistula or esophageal pleural fistula, often pollutants or bacteria into the abscess cavity; abscess chest caused by subdiaphragmatic abscess, subdiaphragmatic infection if not completely removed or foreign body residue in the chest, etc., can form chronic abscess chest because the source of infection is not removed; (3) combined with specific infection, such as combined with tuberculosis bacillus infection of pus thorax. The obvious feature on CT is the visible pleural hypertrophy. Treatment of encapsulated pustulothorax: Encapsulated pustulothorax can be cured surgically if it is not connected to the bronchus. During surgery, the thickened pleura is peeled off and the material in the abscess cavity is removed, and the lung can be expanded.