Angioplasty balloon, used to unblock & widen arteries that have become obstructed by formation of fatty plaques, clots & scar tissue (atheroma). The device appears in its inflated state. Introduced into the artery via a catheter, the slim, cigar-shaped balloon is guided into position using angiography (ie an x-ray image of an artery which has been enhanced by prior injection of a radio-opaque contrast medium). When in position the balloon is inflated, providing a wider channel for blood to flow in. Angioplasty is used to complement laser techniques for vapourising atheroma tissue in cases of arterial disease.