An unusual origin of the right subclavian artery – arteria lusoria

The aortic arch usually gives off three major arterial branches: the brachiocephalic trunk, the left common carotid artery and the left subclavian artery. The most frequently occurring developmental variations of arterial trunks origins are a joined brachiocephalic and left common carotid artery origin, the left vertebral artery branching from the aortic arch, a double aortic arch, and a change of sequence of branching arteries. The current report presents the rare asymptomatic situation of the right subclavian artery originating as the last individual branching from the aortic arch. This abnormality was accidentally discovered in a computed tomography examination of a 69-year old male patient. The examination showed that the artery went towards the neck posteriorly from the trachea. The anatomical anomaly was interpreted as being an arteria lusoria.