Abstract
Imaging technology for coronary artery disease (CAD) has developed in recent years. Several sorts of images are now available for clinical use and they are roughly divided into invasive or non-invasive modality. Invasive, catheter-base, or intravascular devices have some advantages over non-invasive imaging systems. One is that they offer high-resolution images, and another is their real-time image process. Therefore, invasive imaging devices such as intravascular ultrasound (IVUS), optical coherence tomography (OCT), and coronary angioscopy (CAS) are utilized for evaluation of plaque morphology in the culprit lesion, guidance to percutaneous coronary intervention (PCI), or follow-up observation after the intervention. IVUS displays total cross-section of the coronary artery and provides information on vessel remodeling and amount of the plaques. Micron-scale OCT is suitable for close observation of the vessel walls, and CAS can detect thrombus with high sensitivity. In daily practice, IVUS is supplementary to angiograms during PCI procedures. On one hand, OCT and CAS are mainly used as clinical research tools. If non-inferiority of OCT to IVUS is revealed, OCT-guided PCI may be popularized. In case of difficulty in validating lesion characteristics using digital signals on IVUS or OCT images, CAS may help to diagnose the lesion. Intracoronary imaging devices play an important role in detection of vulnerable lesion including vulnerable plaque or stent. It is necessary to understand each image characteristic and to apply the tools properly.
