Fig. 4
From: Paediatric multi-detector row chest CT: what you really need to know
a VRT images (i–iii) demonstrate the presence of a vascular ring, and its relationship with the trachea is seen in the air bronchogram (iv). The trachea is significantly compressed by the dominant right aortic arch and the aberrant left subclavian artery passing behind the trachea and oesophagus. Scanning parameters: 80 kV, 35 eff mAs, 112 ref mAs, 0.44 CTDIvol, 6 DLP. b A surface rendered air bronchogram of the tracheobronchial tree in a 5-year-old child with bronchial atresia in the affected left upper lobe. Scanning parameters: 100 kV, 46 eff mAs, 50 ref mAs, 1.53 CTDIvol, 34 DLP