Thoracic duct terminating on the right side associated with aberrant retro-oesophagal right subclavian artery and truncus bicaroticus.

A case is described showing the following rare combination of anomalies: () the thoracic duct terminating on the right side at the junction of the internal jugular and subclavian veins; () the right subclavian artery arising as the last branch of the aortic arch, beyond the left subclavian artery, and passing behind the oesophagus on its way to the upper limb; and () the right and left common carotid arteries arising by a common stem (`truncus bicaroticus') from the aortic arch. The literature on the subject is reviewed and the embryological basis for the development of these variations is discussed briefly. It is suggested that special attention be directed to the course of the thoracic duct whenever an anomaly of the branches of the aortic arch is observed.