Arterial stents. Coloured 3-D computed tomography (CT) scan of stents (white) in a patient with vascular disease. The aorta is the large artery running down the centre. The two renal arteries branch off the aorta to the kidneys A stent has been placed in the left renal artery (seen on the right here). The aorta branches into the two iliac arteries, which serve the legs. A stent has been placed in the right upper iliac artery (left). A stent is a wire mesh tube used to keep open an artery that had become narrowed. The arteries had become narrowed due to atheroma, fatty deposits, thickening the inner coat of the arteries.