The study is one of the easiest to do and be successful but there are several basic principles that need to be considered. These include;

1. The use of a noncontrast CT would be valuable in cases of intramural hematoma to show the high density in the aortic wall. In most cases it is still easy to recognize and the dose exposure to the patient is typically not worth the potential gain. If you suspect an intramural hematoma on the contrast enhanced scans you can do delayed scans and that would be helpful.
2. In the past scans were often dose from the base of the heart upward but today with faster scanners we typically scan from lung apex distally.
3. The contrast volumes for CT of the thoracic aorta can be as low as 40-50cc when timed correctly and the patient has poor renal function.
4. Injection rate of 4-5cc/sec works well and we prefer to inject thru the left arm as it usually has less artifact
5. Measurement of the aortic size can be incorrectly calculated in ectatic aortas. Center line measurements with computer software is ideal. Computer software is ideal so that measurements on sequential studies are consistent.
6. When evaluating the thoracic aorta comments on the pericardium and coronary arteries are important. Review of the entire scan including the lung fields is critical.
7. Some sites have used dual energy CT to do virtual non contrast scans of the aorta.
8. Post processing is critical with a combination of MPR (especially oblique), volume rendering and MIP imaging
9. In cases with a triple rule out the protocol will be adjusted.