USEFULNESS OF OPTICAL COHERENCE TOMOGRAPHY IN DAILY CLINICAL PRACTICE


Takashi Akasaka, M.D., Ph.D., Wakayama Medical University, Wakayama, Japan

Recently developed frequency-domain optical coherence tomography (FD-OCT) allow us to obtain 75mm length of high resolution intravascular image (10-20 micrometer) within 3 sec during contrast injection through a guiding catheter. This FD-OCT demonstrates the pathophysiology of the coronary atherosclerosis including vulnerable plaques with thin cap fibroatheroma (TCFA) in vivo before percutaneous intervention (PCI). Using this, plaque rupture, erosion and thrombus were observed more frequently (73%, 23% and 100%, respectively) compared with intravascular ultrasound or angioscopy (p<0.01) at the culprit site in acute myocardial infarction. During PCI, it is quite easy to measure the minimum and reference lumen area (MLA and RLA) at the lesion and the length between the proximal and distal references can be demonstrated automatically by FD-OCT, and the decision of the stent size and length becomes very easy and accurate in the daily clinical practice. Three dimensional reconstruction (3D-OCT) may allow us to identify the position of guidewire across the stent struts at the site of bifurcation lesion and to perform the procedure of PCI more effectively. Furthermore, FD-OCT can demonstrate the results of PCI including malapsiton and incomplete stent apposition, tissue and thrombus protrusion and edge dissection more clearly than IVUS (p<0.01) soon after PCI and the degree of neointima coverage and the presence of malaposition more precisely than IVUS (p<0.01) long after PCI. Thus, FD-OCT may allow us to improve the results of PCI and the mechanism of the primary and secondary prevention could be revealed in the near future by FD-OCT.