Multiple, thin-walled cystic lesions of the lung

A variety of diseases produces or mimics multiple, thin-walled, air-containing cavities or cysts in the lung. Although some causes of this pattern are common (bullous emphysema, multiple pneumatoceles), others are relatively rare (cystic bronchiectasis, histiocytosis X, tracheobronchial papillomatosis, and lucite ball plombage). To some extent, the radiographic features of these lesions allow their differentiation, but differential diagnosis can be difficult. This paper reviews their principal features.