Early stage research suggests that the growth of small blood vessels in and around the deposits of fat and calcium leads to the growth of the deposit and may contribute to plaque rupture into the vessel leading to clot formation the process which leads to heart attacks. Drugs which prevent the development of these small blood vessel restrict the development of the deposit, and those that encourage the development of these small blood vessel also increase the development of the deposit. Researchers would like to find out more about the system of blood vessels around deposits of fat and calcium in the larger blood vessels. This involves looking just beneath the surface of the blood vessel wall, and requires a detailed and accurate image. Researchers on this project would like to find out if optical coherence tomography (OCT) is a suitable technique for imaging in this way.