Registration of intracoronary ultrasound image sequence

An approach for registering successive frames in continuous pullback intracoronary ultrasound (ICUS) image sequence covering several cardiac cycles is proposed. The optimal correspondence for each frame in successive cardiac cycles is found. First, a difference matrix is constructed based on comparison of intensity properties in the manner of frame by frame. Then, the approximation of the subject´s cardiac cycle length in frames is estimated from the matrix. Finally, a globally optimal path with the lowest cumulative difference value is searched in the matrix to obtain the correspondence for each frame in successive cardiac cycles. The validity has been demonstrated with clinical image data.