The anatomy of the bronchopulmonary segments: clinical applications.

Abstract

One of the purposes of this report is to illustrate the various sublobar bronchopulmonary segments as they are outlined by disease and to demonstrate the changes in size, configuration, and position which various pathological processes may induce in them. It is our further and more important aim to show how such anatomical knowledge influences considerations of differential diagnosis, prognosis, pathogenesis, and therapy. The report is a continuation of a recent discussion (12) of the roentgen patterns and appearance of lobar collapse. Except for some bronchoscopists and thoracic surgeons, the medical profession as a whole has not realized the value of a precise knowledge of the anatomy of the bronchopulmonary segments. We believe that an accurate understanding of bronchopulmonary anatomy is essential for the intelligent interpretation of abnormal shadows seen on plain roentgenograms as well as bronchograms. The young radiologist should begin his training in diseases of the chest with a study of the bronchopulmonary anatomy. He should not defer it to a later time, when set habits and patterns of interpretation have been acquired. He should be taught to regard each abnormal shadow as an anatomic as well as pathologic problem. Thus he will gain a logical approach to the problems of roentgenologic examination of the chest. The use of such loose descriptive terms as “root fan,” “root triangle,” “root shadow,” “hump shadow,” “hand shadow,” “Anspach's triangle,” etc., should be discouraged. Any abnormal shadow should be described in precise anatomical terms which accurately locate the disease. Anatomical Considerations Among the chief contributors to our present knowledge of bronchopulmonary anatomy are Brock (5), whose excellent monograph is written from the surgeon's point of view, Foster-Carter and Hoyle (7), Jackson and Huber (10), Robbins and Hale (18), and Boyden, Scanneil et al. (4), who have presented extremely detailed drawings of the bronchial anatomy. Other valuable papers have been written by Kramer and Glass (11), Adams and Davenport (1), Peirce and Stocking (16), Behr, Huizinga, and Pothoven (2, 9, 17), Neil, Gilmour, and Gwynne (13), and Blades (3). The bronchial nomenclatures in most common use are those of Brock and of Jackson and Huber. Boyden's group has recommended a system of numbers and letters. In Table I are listed the branch bronchi which are important from a roentgenologic standpoint, as named by these three methods. Brock's terminology will be used in this report. It is simple, descriptive, and logical; the surface anatomical references allow easy commitment to memory. There is little difference between the methods of Brock and of Jackson and Huber. Boyden's numerical system lacks the descriptive qualities of the others and will be used in parentheses. Since the sublobar segments and the bronchi which supply them bear the same names, the numbers will be used interchangeably.