This month's AJR has an article on a patient with a double aortic arch and tracheomalacia, discussed in our literature blog.
This is a 2-months old child with stridor and a suspected vascular ring.
An ECG-gated study was peformed in about 3 seconds. The same dataset was used to show the double aortic arch exquisitely (Figs. 1-4) and then the template was changed to show the lung and trachea. Subsequently the two were fused (Figs. 5, 6) to show how the double aortic arch (red) was encircling and compressing the trachea (blue). With 64-slice scanners, evaluating extra-cardiac vessels, whether they be shunts or aortic or pulmonary abnormalities, is an extremely easy task, performed very quickly.