Title :
Cardiac motion assessment from echocardiographic image sequences by means of the structure multivector
Author :
Alessandrini, M. ; Basarab, Adrian ; Liebgott, H. ; Bernard, O.
Author_Institution :
CREATIS, Univ. de Lyon, Lyon, France
Abstract :
We recently contributed an algorithm for the estimation of cardiac deformation from echocardiographic image sequences based on the monogenic signal. By exploiting the phase information instead of the pixel intensity, the algorithm was robust to the temporal contrast variations normally encountered in cardiac ultrasound. In this paper we propose an improvement of that framework making use of an extension of the monogenic signal formalism, called structure multivector. The structure multivector models the image as the superposition of two perpendicular waves with associated amplitude, phase and orientation. Such a model is well adapted to describe the granular pattern of the characteristic speckle noise. The displacement is computed by solving the optical flow equation jointly for the two image phases. A local affine model accounts for typical cardiac motions as contraction/expansion and shearing; a coarse-to-fine B-spline scheme allows for a robust and effective computation of the model parameters and a pyramidal refinement scheme helps deal with large motions. Performance was evaluated on realistic simulated cardiac ultrasound sequences and compared to our previous monogenic-based algorithm and classical speckle tracking. Endpoint-error was used as accuracy metric. With respect to them we achieved error reductions of 13% and 30% respectively.
Keywords :
biomechanics; echocardiography; image sequences; medical image processing; motion estimation; shear deformation; speckle; ultrasonic imaging; cardiac deformation estimation algorithm; cardiac motion assessment; cardiac ultrasound; characteristic speckle noise; classical speckle tracking; coarse-to-fine B-spline scheme; contraction-expansion cardiac motions; echocardiographic image sequences; endpoint error; error reductions; granular pattern; image phases; local affine model; monogenic signal; monogenic signal formalism; optical flow equation; perpendicular wave superposition; phase information; pyramidal refinement scheme; realistic simulated cardiac ultrasound sequences; shearing; structure multivector; temporal contrast variations; Computational modeling; Equations; Mathematical model; Motion estimation; Myocardium; Speckle; Ultrasonic imaging; echocardiography; image phase; motion estimation; structure multivector;
Conference_Titel :
Ultrasonics Symposium (IUS), 2013 IEEE International
Conference_Location :
Prague
Print_ISBN :
978-1-4673-5684-8
DOI :
10.1109/ULTSYM.2013.0392