Fig. 1.

Representative cross-sectional images of coronary atherosclerosis by OCT. a, A mild concentric fibrous plaque, characterized by homogenous, signal-rich regions. Lipidic plaques (b, c, and d) are characterized by superficial signal-rich region followed by a drop in signal, as a result of high backscattering and attenuation (asterisks). The fibrous cap can be identified as a homogeneous signal-rich band overlying the lipid-rich core. b, A lipid-rich plaque with thick cap (cap thickness at the thinnest part measured 178 μm). c, A thin-cap fibroatheroma, defined by a thin-cap (46 μm at its thinnest part) overlying a lipid-rich plaque. d, Rupture of the fibrous cap overlying a lipid-rich plaque can be observed