Title
Biventricular myocardial strains via nonrigid registration of AnFigatomical NURBS models
Abstract
We present research in which both left and right ventricular deformation is estimated from tagged cardiac magnetic resonance imaging using volumetric deformable models constructed from nonuniform rational B-splines (NURBS). The four model types considered and compared for the left ventricle include two Cartesian NURBS models-one with a cylindrical parameter assignment and one with a prolate spheroidal parameter assignment. The remaining two are non-Cartesian, i.e., prolate spheroidal and cylindrical each with their respective prolate spheroidal and cylindrical parameter assignment regimes. These choices were made based on the typical shape of the left ventricle. For each frame starting with end-diastole, a NURBS model is constructed by fitting two surfaces with the same parameterization to the corresponding set of epicardial and endocardial contours from which a volumetric model is created. Using normal displacements of the three sets of orthogonal tag planes as well as displacements of contour/tag line intersection points and tag plane intersection points, one can solve for the optimal homogeneous coordinates, in a weighted least squares sense, of the control points of the deformed NURBS model at end-diastole using quadratic programming. This allows for subsequent nonrigid registration of the biventricular model at end-diastole to all later time frames. After registration of the model to all later time points, the registered NURBS models are temporally lofted in order to create a comprehensive four-dimensional NURBS model. From the lofted model, we can extract three-dimensional myocardial deformation fields and corresponding Lagrangian and Eulerian strain maps which are local measures of nonrigid deformation. The results show that, in the case of simulated data, the quadratic Cartesian NURBS models with the cylindrical and prolate spheroidal parameter assignments outperform their counterparts in predicting normal strain. The decreased complexity associated with the Cartesian model with the cylindrical parameter assignment prompted its use for subsequent calculations. Lagrangian strains in three canine data, a normal human, and a patient with history of myocardial infarction are presented. Eulerian strains for the normal human data are also included.
Year
DOI
Venue
2006
10.1109/TMI.2005.861015
IEEE Trans. Med. Imaging
Keywords
Field
DocType
biomechanics,biomedical MRI,cardiology,deformation,image registration,medical image processing,splines (mathematics),AnFigatomical NURBS Models,Cartesian NURBS models,Eulerian strain maps,Lagrangian maps,biventricular myocardial strains,end-diastole,endocardial contours,epicardial contours,nonrigid image registration,nonuniform rational B-splines,quadratic programming,tagged cardiac magnetic resonance imaging,ventricle,ventricular deformation,volumetric deformable models,weighted least squares,B-splines,NURBS,cardiac motion,deformation,myocardial strain,nonrigid registration,tagged MRI
Least squares,Parametrization,Eulerian path,Artificial intelligence,Quadratic programming,Geometry,Cartesian coordinate system,Homogeneous coordinates,Computer vision,Mathematical optimization,Line–line intersection,Mathematics,Image registration
Journal
Volume
Issue
ISSN
25
1
0278-0062
Citations 
PageRank 
References 
24
1.82
20
Authors
2
Name
Order
Citations
PageRank
Nicholas J. Tustison1136258.82
Amir A. Amini244363.30