Abnormal bronchus morphology Traction bronchiolectasis 2020-04-25T12:59:28Z Distortion of the bronchiolar airways due to mechanical traction on the bronchi resulting from fibrosis of the surrounding lung parenchyma. CT findings represent irregular bronchiolar dilatation caused by surrounding retractile pulmonary fibrosis. Dilated airways are usually identifiable as such but may be seen as microcysts.