Williams-Campbell syndrome is a rare type of cystic bronchiectasis that is due to defective cartilage of fourth-to sixth-order bronchi. The diagnosis has been made either at autopsy or by bronchographic findings. The article describes an adult case of this syndrome with CT findings that are characteristic of this entity. CT showed areas of emphysematous lung parenchyma distal to the dilated bronchi, suggesting bronchiolitis obliterans secondary to proximal cystic bronchiectasis. These findings are useful in differentiating Williams-Campbell syndrome from other causes of cystic bronchiectasis, thus obviating bronchography.
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