Balloon angioplasty. Coloured X-ray of the abdomen of a 45-year-old patient with a history of thrombosis (blood clots) in the inferior vena cava (vein), which have narrowed (stenosed), damaged and weakened the wall of the vein. This image shows the vein being repaired using a balloon angioplasty. A long thin tube with a deflated balloon at the tip (balloon catheter, dark, centre left) is inserted into the blood vessel. When the catheter is within the narrowed region, the balloon is inflated (seen here) to expand the vessel. Stents (wire mesh tubes) are then permanently implanted to hold the blood vessel open and reinforce the weakened wall.