Fig. 20From: Paediatric multi-detector row chest CT: what you really need to knowCT images (a, b) show severe tracheobronchial compression in a baby with biphasic stridor. An aberrant left pulmonary artery is seen arising from the right pulmonary artery (a), creating a vascular sling around the trachea as it passes posteriorly causing almost complete occlusion of the distal trachea (b), with marked narrowing of the left main bronchus. Scanning parameters: 80 kV, 58 eff mAs, 60 ref mAs, 0.86 CTDIvol, 14 DLPBack to article page