Studies on the Relationship between Pulmonary Tuberculous Cavities and Draining Bronchi, by Injecting Acrylic Resin

Abstract

We have studied 83 tuberculosis lungs removed at operation or at autopsy, three-dimensionally, pathologically, and histologically by means of the plasticinjected casts, and further investigated the relationship between cavities and draining bronchi and have reached the following conclusions. 1). The 7th to 9th bronchi in each lobe are big enough to play the role of draining bronchi, thus it may be said that the caseated foci larger than a lobule are facing directly to these bronchi. This is why these foci are always threatened by the danger of cavitation. 2). It is extremely difficult for a cavity to be cut off from the trachea by connective tissues obstruction of its draining bronchus; indeed this kind of obstruction has not been found at all in our studies. 3). There is a parallel relation between the state of a cavity and the tuberculous lesion of its draining bronchus, but in many cases there is a difference in the extent of the disease. Accordingly it is necessary to keep in mind the state of the draining bronchus at the time of treatment of the cavity. 4). The modes of opening of a cavity into its draining bronchus are; (1) a cavity opening into the end of a bronchus at its top (pattern I), and (2) a cavity opening into the lateral wall of a bronchus. According to the different stages of the developing cavity, the patterns seem to alter as follows⟶pattern I⟶pattern II⟶pattern I. 5). A cavity, less than 1.5cm in diameter, has usually one draining bronchus, while a bigger cavity than the above has generally two or more bronchi, and a cavity larger than the above two kinds of cavities has several draining bronchi, but seldom more than four. The drainidg bronchi from megacavities are fewer in number but manytimes larger in size than those of the above cavities. This is apparently due to the fact that the other small draining bronchi were obliterated during the course of the development of the disease. 6) A cavitation is not necessarly limited to a single pulmonary segment, but the draining bronchus of a cavity, which is 1.5cm. in diameter, communicates with the two neighboring segments, especially those of megacavities sometimes communicate with many segments. The intersegmental partitions, which consist of connective tissue and branches of pulmonary veins, are not firm enough to check caseation and cavitation of the intersegmental connective tissue during the development and fusion of the tuberculous focus. 7). Morphological changes in draining bronchi such as stenosis, obstruction, partial dilatation, and single or multiple flexions are observable. Partial stenosis is distinctly observable at the opening of the bronchi into cavities, and in other parts, a partial stenosis and a partial dilatation of the draining bronchus occur alternatly and the extent of the lesions gradually decreases in degree towards the pulmonary hilum. The morphological changes of draining bronchi parallel the degree of the tuberculous lesion around the cavity or the caseated focus. 8). With pneumothorax the bronchi take the form of stratification roughly parallel to the axis of a lobe, and the bronchial bending and obstruction are not recognized. Even in highly collapsed lungs of perfect pneumothorax, bronchial obstruction is not recognizable, but only the shortening narrowing of bronchi. 9). One form of direct treatment of tuberculosis, the incision treatment, aims at cleaning the cavity and cicatrized healing by means of draining the contents of cavity through the body wall, and not through a draining bronchus. But unfortunately this treatment is not very through when we consider the relationship between a cavity and the bronchial tuberculous lesion. From this point of view resection seems to be the more thorough treatment, but indications for this treatment are limited to cases in the early stage, if we consider bronchial lesions and disseminated foci. Therefore, those caseated foci which seems to tend towards softening and deca