Congenital Cystic Disease of the Lung

Abstract

CONGENITAL cystic disease of the lung is encountered frequently enough to merit the attention of clinicians and radiologists. It may not be amiss to bring its various manifestations to your notice, for not infrequently its diagnosis will be a purely radiological one. I shall endeavor, therefore, to sketch the anatomy and clinical pictures of this disease, to explain as far as I am able its radiological characteristics, and to discuss six fairly certain and several doubtful cases that have come under my observation. You may judge of its frequency by the fact that, while I was able to present four cases to the Pacific Coast Surgical Association in February of this year [1930], I have in the intervening nine months seen certainly two others, perhaps more. The lung develops as a bud sprouting from the primitive esophageal tube. Complexity of adjoining structures simultaneously undergoing changes in size, shape, and position render the lung peculiarly prone to developmental variations and anomalies, the number of its lobes and their position and relation to the great vessels being subject to frequent variation. The growth and obliteration of Cuvier's duct, a duct connecting the cardinal veins with the heart, influence particularly the left lower lobe. Sauerbruch and his assistant, Lotzin (1), have thought that pressure from this duct has much to do with the formation of bronchiectases, many of which they think are congenital. They explain the predilection of bronchiectasis for the left lower pulmonary lobe on these grounds. By careful studies they have found abnormal displaced fetal remnants scattered through the parenchyma of many bronchiectatic lobes. Accordingly as the various deforming structures act upon the fetal lung early or late, and more or less extensively, so greater or lesser areas of lung are affected. Thus small particles of lung tissue may become partially or totally detached from the rest of the organ; solitary cysts may occur in the body of the lung itself, or adjoining it in the structures of the mediastinum, or quite separately. Accessory rudiments have been described as lying even in the abdominal cavity, quite cut off from the rest of the lung by closure of the diaphragm. If the cysts retain an open bronchial connection, they will contain air; if the bronchi leading to them are closed or end blindly, they contain fluid. The cysts may be solitary or multiple; an entire lobe, or both lower lobes, or even an entire lung may be the object of cystic degeneration. The cysts may be minute; they may be very large, so that a lobe will resemble a bunch of large grapes, or a whole lobe may be converted into a single thin-walled cyst. Clinically they may be separated into two forms: the infantile, with alarmingly acute attacks of dyspnea, and the more chronic form which comes to notice mainly by reason of superimposed infections.