Congenital cyst of the lung may be defined as an intrapulmonary fluid sac of which the wall is composed of bronchial tissue and the fluid content is a product of the bronchial epithelium. Its formation is attributed to an anomalous occlusion of the bronchus in the embryo.
This condition, formerly seldom encountered, is now being recognized with increasing frequency with present day improved methods of roentgenologic technic. The literature is sufficiently complete to enable the well informed to make a diagnosis of cystic disease when the proper procedure of examination is followed. We believe that a larger number of cases would be discovered if routine roentgenograms of the chest were made on atypical pulmonary infections at the end as well as at the beginning of the disease. This statement is well supported by the cases cited by Kostlin,1 Barlow,2 Coats,3 Frühwald,4 Debré and Blinder5 and