Aortic coarctation by cardiovascular CT angiography.

The patient is a 12-year-old boy who underwent prospectively gated step-and-shoot chest CT (computed tomographic) angiography with a 64-multislice CT scanner (64-MSCT) for a preliminary diagnosis of coarctation of aorta. The data was acquired in a manner to significantly minimize radiation to the patient, including use of 80 kVp (rather than 120 kVp, much more commonly employed in cardiac CT), low mA (120 mA, rather than typical 400 mA), and prospective acquisition using a VCT 64 detector scanner (General Electric, Milwaukee, WI) (Figs. 1 and 2). Total radiation dose was 0.9 mSv, despite imaging from sternal notch to liver. Findings included dilated ascending aorta (43 mm diameter) and a total coarctation of descending aorta with very well-developed collaterals. The left internal mammary artery and right internal mammary artery were noted to be very large (7 mm diameter).