Intravascular photoacoustic detection of vulnerable plaque based on constituent selected imaging

Abstract

Atherosclerosis, a disease of the large arteries, is the primary cause of heart disease and stroke. Over decades, atherosclerosis is characterized by thickening of the walls of the arteries, only advanced atherosclerotic disease could be observed. Photoacoustic imaging is a hybrid imaging technique that combines the advantages of high spatial resolution of ultrasound with contrast of optical absorption. In this paper, we present an intravascular photoacoustic (IVPA) imaging system to characterize vulnerable plaques by using the optical absorption contrast between different constituents. Epidemiological studies have revealed several important plaque constituents associated with early atherosclerosis, such as macrophage, cholesterol, lipid, calcification, and so on. We chose a section of lipid rich atherosclerosis artery and a section of normal artery as the phantom. Two IVPA images of them are given to show the difference between sick and normal. As a new method of detecting vulnerable plaque, IVPA constituents imaging will provide more details for diagnosis that offer an enticing prospect in early detecting of atherosclerosis.