Objective To evaluate the value of X-ray and spiral computed tomography （SCT） in the diagnosis of Swyer-James syndrome （SJS）.Methods A total of 28 patients

12 males and 16 females

were studied retrospectively.Ages ranged from 11 to 57 years

the mean age was 32 years.All patients underwent inspiratory chest X-ray films

5 with expiratory chest films and 1 with bronchogram.Furthermore

inspiratory and expiratory SCT scans were performed.The SCT findings were analyzed and compared with X-ray films.Results SCT demonstrated 56 lobes with hyperlucency and diminished vascularity.The size of 51 lobes were smaller and 5 were normal.X-ray films showed that hyperlucency was only in 29 lobes

in which 19 lobes were small-sized and the other 10 lobes normal.There were 56 lobes with air-trapping on expiratory SCT scans

but only 5 lobes with air-trapping on expiratory X-ray films.Bronchogram in 1 case demonstrated bronchiectasis and bronchiolitis obliterans.SCT showed 24 patients with bronchiectasis

9 patients with tuberculosis

10 patients with bronchiolitis

and 2 with segmental collapse.Conclusion SCT scan is superior to chest radiography in the diagnosis and differential diagnosis of SJS.