Right aortic arch causing left bronchus obstruction.

A case is reported of a right aortic arch vascular ring composed of a right aortic arch with mirror image branches and a retroesophageal left aortic diverticulum with a left ductus arteriosus that appeared as a possible foreign body aspiration in an infant. This vascular ring caused partial occlusion of the left main bronchus with air trapping. A discussion of right aortic arch vascular rings and vascular anomalies that have caused unilateral lung hyperinflation is included in this report.