In a child with coarcation of aorta, all the following are seen in plain chest radiograph except:

Ans: C ('E' Sign or 'Reverse Three sign') Ref: Cardiac X-rays by V. Chockalingam & .A. Chockalingam. 1st edition. Elsevier. 2008. Page 99.Explanation:'E' Sign or "Reverse Three sign' is feature of coarctation, but seen in barium swallow, not in plain chest radiograph.Features of Coarctation of AortaLeft ventricular configurationProminent ascending aorta due to hypertension and bucuspid aortic valve'Three sign': The upper convexity is due to pre-stenotic dilatation and the lower convexity is due to post-stenotic dilatation. The mid portion represents the coarc ted segment'E' Sign or 'Reverse Three sign': Seen in barium swallow due above aortic shadowsRib notching: Bilateral rib notching is seen between the third and eighth posterior ribs along its lower border usually after the age of 9 years.Unilateral rib notching: A feature of coarctation, if it involves the origin of the left subclavian artery also.Differential diagnosis for rib-notchingRib notching is also seen in the following conditionsChronic superior vena cava obstructionChronic inferior vena cava obstructionAortoarteritis in rare occasionIntercostal neurofibromatosisIntercostal arteriovenous malformationsPost Blalock-Tausig shunt