Angioplasty techniques. Computer illustration of balloon and laser angioplasty. Angioplasty is a surgical procedure to unblock and widen arteries that are narrowed or obstructed due to the formation of fatty plaques (atheroma), clots or scar tissue. A catheter (tube) is inserted into the artery. In the established technique (top), a balloon (beige) is inflated inside the affected area. The newer method (bottom) uses pulses of laser light (transmitted through a fibre optic) to destroy the blockage ahead of the catheter. This may be less traumatic to the arterial wall, decreasing the chance of narrowing recurring.