Figure 3. Aneurysm of aberrant right subclavian artery(AARSA) in a 23-month-old boy with truncus arteriosus. Volume-rendered three-dimensional images in (a) posterior and (b) anteriocranial projection show aneurysmatic aberrant right subclavian artery (arrow) arising from the left-sided arch (A) and passing from the left to the right. (c) Multiplanar coronal reformation demonstrate narrowing of the pulmonary artery (arrow) between the aberrant right subclavian artery (*) and the aorta (A) and moderate cardiomegaly. R, right side; L, left side.