Characterization of ventricular torsion in healthy subjects using Gabor filters and a variational framework

Abstract

In this work, we present a fully automated method for tissue deformation estimation in tagged magnetic resonance images (TMRI). The method consists of two main stages: in the first one, we use Gabor filter banks, tuned independently for each left ventricle level, that allows to obtain optimally filtered complex images the phase of which is a property that remains constant along the cardiac cycle. This fact can be thought as the brightness constancy condition required by classical optical flow (OF) methods. Pairs of these filtered sequences, together with a variational formulation are used in a second step to obtain dense continuous deformation map that we call Harmonic Phase Flow. This method has been used to determine reference values of ventricular torsion (VT) in a set of 8 healthy volunteers. The results encourage the use of VT as a useful parameter for ventricular function assessment in clinical routine. 1.