In a student course of gross anatomy dissection at Kanagawa Dental University in 2011, we encountered anomalous case of the right subclavian artery arising from the aortic arch as the last branch in an 84-year-old Japanese male cadaver. The anomalous artery ran obliquely upward, passed behind the esophagus and trachea, and ultimately ran toward right scalene gap. The area of distribution of the anomalous artery was normal. We report a case of retroesophageal right subclavian artery, and discuss its development, or relation with the thoracic duct, and its clinical importance. Despite this type of variation being relatively rare, reports on such a case have been accumulating. Owing to the recent development of CT and MRI, the number of clinical reports on this anomaly has been increasing.
Keywords: aortic arch; arterial anomaly; retroesophageal right subclavian artery; thoracic duct.