To improve the longitudinal visualization and suppress the motion artifacts due to cyclic cardiac motion of continuous pullback intracoronary ultrasound(ICUS) image sequence covering several cardiac cycles,the cross-sectional ICUS image sequence is off-line gated with image analysis techniques.Firstly,a dissimilarity matrix is constructed through comparing intensity features of ICUS frames in a frame-by-frame manner.Then,an optimal path with the lowest cumulative dissimilarity value is found in the dissimil...