Intravascular ultrasound (IVUS) and Optical Coherence Tomography (OCT) imaging are two methods used to explore the inside of the coronary artery and especially atherosclerotic plaques which can block it, causing heart attacks and ischemia.Nevertheless, the catheter used in IVUS can move freely inside the coronary due to the heart movement. This movement is not linear as opposed to the pullback movement. Consequently, the images turn out to be disordered.Thus, our first objective is, from a database of more than 100 exams, to validate a method of synchronization of those images within the cardiac cycle. Therefore, we will rebuild the volumes of each phase of the cardiac cycle using measurable characteristics of the images. Within each phase, the movement of the catheter is almost only due to the pullback. Hence, the images are sorted by phase. Moreover, due to the nonlinear longitudinal motion, we calculate the spatial alignment between each phase so as to have regions of the coronary artery spatially equivalent. We will also apply these processes on OCT imaging.Hence, we will make a dynamic analysis of the coronary artery, which will consist primarily in a segmentation of the coronary cross-sectional images in order to separate the different layers. Therefore, we consider establishing relationships between the changes in volume, elasticity and pressure, as well as changes in texture that could indicate the presence and kind of plaques.Afterwards, we will propose a friendly interface in Matlab, to present the quantitative results useful to doctors, with possibility to reorder any number of IVUS or OCT images and also view the significant parameters of the dynamic of coronary artery.
News published in Agência FAPESP Newsletter about the scholarship: