Postmortem Computer Tomography Appearance of the Aortic Arch in Children: What Is Considered Normal?

Virtual autopsies by computer tomography (CT) or magnetic resonance imaging can be valuable in cases of unexplained infant death. The radiologist must be familiar with the normal appearance of all the segments of the thoracic aorta in normal and deceased children. A thorough review of the literature revealed no prior articles describing CT changes in the ascending aorta or the aortic arch in pediatric virtual autopsies.

To compare the CT appearance of the thoracic aorta in deceased children and in those younger than 3 years of age.

Hospital registries were searched for cases of unexpected deaths in children younger than 3 years old, with a postmortem CT available, as well as for clinically indicated chest CT in children of the same age during a 5 year period. The ascending aorta (AA), aortic arch (arch), and the descending aorta (DA) diameters were measured. Student's t-tests and Mann-Whitney U-tests were used to compare the two groups.

A total of 64 scans were reviewed: 35 postmortem and 29 performed on living patients. The differences in the diameter and the ratios of the diameter between the AA and the arch, as well as between the arch and the DA in the postmortem and living groups were statistically significant (P < 0.05).

On postmortem CT scans, we found focal tapering of the aortic caliber at the level of the arch between the origin of the brachiocephalic artery and left subclavian artery. This finding should not be misinterpreted as a hypoplastic aortic arch.