Frequency of variations in aortic arch anatomy depicted on multidetector CT

Schematic diagram depicting the embryological development of the aortic arch and its branches.

Left anterior oblique sagittal thickslab MPR (a) and volume rendered (b) MDCT images of the same patient showing the “bovine” arch. Innominate artery (dotted arrow) and right common carotid artery (solid arrow) share a common origin.

Axial (a), left sagittal oblique thickslab MPR (b) and volume rendered (c) MDCT images in the same patient. The left vertebral artery arises directly from the arch (black arrow). Note also bovine configuration (white arrow).

Volume rendered MDCT image viewed from posterior (a) showing an aberrant right subclavian artery (open arrow) and a shared origin of the innominate and left common carotid arteries (arrow). Normal left subclavian artery (dotted arrow). Axial image in the same patient (b) shows a short occlusion of the origin of the aberrant right subclavian artery (arrow).

Volume rendered MDCT images from the same patient viewed from posterior (a), and from left lateral (b). There is a complex tortuous right sided arch with the left subclavian artery arising from the descending thoracic aorta (solid arrow). The left common carotid artery is the first branch (dotted arrow), the right common carotid artery second branch (dotted open arrow), right vertebral artery third (arrow head), and right subclavian artery fourth (open arrow).

Left lateral volume rendered MDCT image. Incidental aortic coarctation (arrow). Note the extensive collateral circulation via internal mammary (arrow head) and intercostal arteries (dotted arrows).

Right posterior oblique volume rendered MDCT image. The right vertebral artery (arrow) arises from the right common carotid artery. There is a right aberrant subclavian artery (arrowhead).