Right aortic arch with left descending aorta (circumflex aorta) Roentgenographic diagnosis

Right aortic arch with retroesophageal segment is a rare anomaly with distinctive roentgenographic features. We present 2 patients, who on the barium oesophogram had an additional finding which has not previously been described. The typical features include an indentation on the right upper barium filled oesophagus (in the antero-posterior view), an oblique indentation descending from right to left (caused by the retroesophageal segment) and the left descending aorta. The oblique indentation has not previously been described. The embryology and incidence of the lesion are briefly discussed.