The Roentgen Appearance of Lobar and Segmental Collapse of the Lung: A Preliminary Report

Abstract

Some degree of collapse or atelectasis of the lung, a lobe, or a segment of a lobe, is frequently associated with certain disease processes in the chest, such as foreign body, tumor, bronchiectasis, and tuberculosis. Inasmuch as collapse is often confused with other lesions, in which the treatment differs, as pneumonia and infarct, its recognition is important. In this paper we shall present certain roentgenologic findings in collapse which may be the first to be observed and may be of more importance in diagnosis than the commonly accepted signs—elevation of the diaphragm, shift of the mediastinum, narrowing of the rib spaces, and demonstration of the shadow of the collapsed lobe. We have restricted the use of the word “collapse” to a decrease in the size of a lobe or a part of a lobe, and of the word “atelectasis” to airlessness. From a total of 70,000 chest examinations made at the Massachusetts General Hospital during the last six years, we reviewed in detail 1,000 that led to a diagnosis of tumor, bronchiectasis, or foreign body, as well as a number of cases of tuberculosis associated with definite collapse. After discarding the cases for which there were not adequate films in both posteroanterior and lateral projections, there remained approximately 500 cases in which at least one lobe was less than two-thirds of its normal size. The findings presented in this report are based on this series of 500 cases. Technic The examination of patients with suspected collapse should begin with fluoroscopy, which will determine the dynamics within the chest and indicate which films will best demonstrate the lesion. In the majority of instances, the routine posteroanterior, the lateral, and the Potter-Bucky or grid projections will give the necessary information. In certain cases, particularly those with bilateral lesions, oblique views will provide additional data. Many cases will require bronchography, and a few will call for laminagraphy for confirmation of a diagnosis. Normal Chests It has been our impression for some time that roentgenologic localization of the fissures of the lung is possible by the demonstration of thin lines of increased density, which we have called septa. The term “septum” rather than fissure has been used because a pulmonary fissure is a potential space, which is not demonstrable by x-ray, whereas the two pleural surfaces, which are in apposition, cast a well defined shadow. In order to substantiate this impression, and to determine the normal variation and location of the septa, 150 patients who had no pulmonary complaints were examined by means of both postero-anterior and lateral roentgenograms. In the majority of cases, the location of the minor fissure on the right is demonstrable on the postero-anterior projection, while in the lateral view, the major septa, or fissures, are also shown.