Evaluation of Selective Alveolo-Bronchography with Fuji Computed Radiography and X-ray CT

Abstract

Selective alveolo-bronchography (SAB) has been routinely used to evaluate anatomical changes in the bronchiole and its distal air spaces. A narrowing of the bronchiole and abnormal pooling of contrast medium in the destroyed air space are the prime findings. Since the object of radiography is extremely thin, direct magnification radiography is mandatory to obtain radiologic details. However, the problem with this technique is that radiographic quality varies depending upon the size of the patient and the concentration of contrast medium to be introduced in the lung. This study had two goals. One was to improve the image quality of SAB by Fuji Computed Radiography (FCR). FCR provides radiographs with a good contrast and stable density throughout a wide range of exposure factors which occur in the use of SAB. The other goal was to separately evaluate morphological abnormalities in the outer and inner zones of the lung using X-ray CT. This idea was derived from our observations in positron emission tomographyusing ^<13>Nwhich revealed air trapped in the outer layer of the lung in diffuse panbronchiolitis. Fourteen patients underwent SAB, including two cases of bronchiectasis, one of cancer, one of silicosis, one of post-inflammatory scar, four of diffuse panbronchiolitis and five of chronic pulmonary emphysema. Of these fourteen cases ten and twelve cases received FCR and CT examinations, respectively.