抄録
Selective alveolo-bronchography (SAB) and lung biopsy were performed in 51 patients with distal lung lesions to perform morphological classification and the impairment of their respiratory function was evaluated. SAB was performed through the use of an X-ray television system (MODEL SHZ Toshiba Medical Systems Co.) with a 0.1mm focal length magnifying tube lens to yield a 3 to 4-fold magnified SAB image.
According to the patterns of morphological abnormalities which were observed with SAB, the patients were classified into 4 main groups; the group with narrowed terminal bronchioles (type I), the group with dilated terminal bronchioles (type II), the group with alveolar ductectasis (type III) and the group with abnormal alveolar figures (type IV). Types I and II were observed equal members in most cases diagnosed histologically as bronchiolitis or interstitial pneumonia. In the group with marked dilatation, there were patients who had been diagnosed pathologically as having pulmonary fibrosis or bronchiolitis obliterans. Although the patients with pulmonary emphysema consistently had type IV patterns, there was one patient in whom type I pattern was observed.
Most patients in whom the presence of lesions was morphologically identified by means of SAB and transbronchial lung biopsy (TBLB) showed hypoxemia with abnormally increased alveolar-arterial O2 tension difference (AaDO2) and arterial-alveolar N2 tension difference (aADN2). It was confirmed that the hypoxemia observed in these patients resulted from the impaired ventilation-perfusion ratio distribution in the lungs.
SAB findings were systematically evaluated according to 7 parameters such as narrowing, dilatation, obstruction and poor branching of the terminal bronchioles, alveolar duct ectasis, uneven alveolar filling and abnormal alveolar figures. The total score calculated from these parameters was significantly higher in patients with pulmonary emphysema and pulmonary fibrosis as opposed to those with bronchiolitis and interstitial pneumonia. There was a significant correlation between the total score and aADN2 in patients with pulmonary emphysema.
In this study, the author evaluated the pathophysiology of patients with distal lung lesions on the basis of morphological data obtained by means of SAB and TBLB. As a result, it was possible to establish definite criteria for the clinical diagnoses of these patients.
