Fig. 1

Representative optical coherence tomography images. a Thin cap fibroatheroma (TCFA) was displayed as a lipid-rich plaque (maximum lipid core > 90°) with fibrou cap thickness < 65 μm. b Macrophage infiltration (arrows) was defined as clusters of bright spots with backward shadowing. c Microchannel (arrow) was shown as a black hole in the plaque. d Ruptured plaque (arrow) was observed as a plaque with the discontinuous fibrous cap and a communication between the lipid core and the lumen