Subcostal imaging including ... presence or absence of aortic arch interruption or hypoplasia. If the aortic arch is interrupted, the PDA, via the ductal arch, will supply the descending aorta.

the right aortic arch (on the right of course), the aberrant innominate artery posteriorly and the left PDA (or ­ligamentum) on the left. CT imaging is useful for patients who are unable to ...