[Pulmonary sarcoidosis: CT features and the changes after glucocorticoid therapy]

To investigate the CT features of pulmonary sarcoidosis and to follow the changes after glucocorticoid therapy.

CT scans and clinical data of 90 patients with histologically confirmed pulmonary sarcoidosis were retrospectively reviewed. CT follow-up was carried out 5-30 d following therapy in 43 cases. The follow-up lasted 3-48 months.

The main CT finding of pulmonary sarcoidosis was nodules which were present in 69 cases (77%), mostly distributed around bronchovascular bundles (n = 37, 41%). Other abnormalities included consolidation (n = 31, 34%), ground-grass ( n = 39, 43%), thickening of bronchovascular bundles (n = 30, 33%) interlobular septal lines (n = 58, 64%), fibrosis (n = 17, 19%), air-trapping (n = 3, 3%) bronchial narrowing (n = 8, 9%), pleural thickening (n = 42, 47%), hilar and mediastinal adenopathy (n =76, 84%). Two or more radiological patterns were present in 83 cases. Twenty-five cases of nodules (25/30), 9 cases of consolidation (9/15), 11 cases of ground-grass (11/16), 10 cases of thickening of bronchovascular bundles (10/12) were improved after therapy. Ten cases of interlobular septa (10/22), 1 case of diffuse linear changes (1/3), but no bronchial distortion (0/4) and honeycombing (0/2), were improved.

The CT manifestations of pulmonary sarcoidosis are varied, with some specific radiographic features. The radiological diagnosis and the effect of glucocorticoid therapy can be evaluated by repeated CT scanning. Nodules, consolidation, ground-grass, and thickening of bronchovascular bundles can be improved markedly after glucocorticoid therapy, but bronchial distortion, linear changes and honeycombing can not.