Coronary artery motion modeling

摘要

A method for tracking coronary artery motion includes constructing (11) a centerline model of a vascular structure in a base phase image in a sequence of 2D images of coronary arteries acquired over a cardiac phase, computing (12), for each pixel in a region-of-interest in each subsequent image, a velocity vector that represent a change in position between the subsequent image and base phase image, calculating (13) positions of control points in each phase using the velocity vectors, and applying (14) PCA to a P×2N data matrix XT constructed from position vectors (x, y) of N centerline control points for P phases to identify d eigenvectors corresponding to the largest eigenvalues of XXT to obtain a d-dimensional linear motion model {circumflex over (α)}p, in which a centerline model for a new image at phase p+1 is estimated by adding {circumflex over (α)}p to each centerline control point of a previous frame at phase p.

主权项

1. A method of tracking coronary artery motion in a sequence of 2D images, comprising the steps of:
constructing a centerline model of a segmented vascular structure in a base phase image in a sequence of 2D images of coronary arteries acquired over one or more cardiac phases; computing, for each pixel in a region-of-interest (ROI) in each subsequent image in the sequence of 2D images, a velocity vector that represent a change in position between the subsequent image and base phase image in the sequence of 2D images; calculating positions of control points i in each phase p using the velocity vectors viT=(vi,x, vi,y)T; and applying PCA to a P×2N data matrix XT constructed from position vectors (x, y) of N centerline control points {V0(p), V1(p), . . . , VN−1(p)} for P phases to identify d eigenvectors corresponding to the largest eigenvalues of XXT to obtain d-dimensional linear motion modelα^p←m_p+∑i=1d⁢⁢αp,i⁢vi,where mp is a mean value of 2N control points positions (x, y) at phase p of the cardiac cycle, vi is an eigenvector of U=cov(XXT), and the αp,i's are determined for each phase p, wherein a centerline model for a new image at phase p+1 is estimated by adding {circumflex over (α)}p to each centerline control point of a previous frame at phase p.