QMRITools`CardiacTools`
QMRITools`CardiacTools`
HelixAngleCalc
HelixAngleCalc[eigenvectors, mask, vox] calculates the helix angle matrix of cardiac data using only a left ventricle mask.
HelixAngleCalc[eigenvectors, mask, maskp, vox] calculates the helix angle matrix of cardiac data using only a left ventricle mask, and a maskp for visualization.
HelixAngleCalc[eigenvectors, mask, centerpoint, vec, inout, vox] calculates the helix angle matrix of cardiac data using only a left ventricle mask.
HelixAngleCalc[eigenvectors, mask, maskp, centerpoint, vec, inout, vox] calculates the helix angle matrix of cardiac data using a left vantricle mask and a maskp for visualization.
eigenvectors are the tensor eigenvectors calculated with EigenvecCalc.
mask is a mask of the left ventricle.
maskp is a mask used for visualization.
vox is the voxels size, {slice, x, y}.
The folowing values are calculated automaticlay Using CentralAxes but can also be provided as an input.
centerpoint is the center of each slice calculated with CentralAxes.
inout is the inner and outer radius calcualted with CentralAxes.
vec is the vector describin the central axes of the heart, calculated with CentralAxes.
Output is het fiber angle matrix FAM = {9, slice, x, y} or {FAM, plot}.
The angles are in degrees.
HelixAngleCalc[] is based on DOI: 10.1186/1532429X17S1P15.
Details
 The following options can be given:

ShowPlot True ShowPlot is an option for CentralAxes, HelixAngleCalc and CardiacCoordinateSystem. True shows the fit of the central axes and outpu the plot as extra output. LCMMethod "WallMap" LCMMethod is an option for HelixAngleCalc and LMCSytemCalc. Can be "CentralAxes" or "WallMap". "CentralAxes" uses wall distance calculation using projection of the centarl axes and circular approximation of the ventricle. This method is fairly fast and uses CentralAxes internaly. "WallMap" uses wall distance interpolation and subsequential gradient calculation. Can take long for high res datasets but is most accurate. Uses CalculateWallMap internaly. AxesMethod "Quadratic" AxesMethod is an option for HelixAngleCalc and CentralAxes and CardiacCoordinateSystem. Can be "Linear", "Quadratic", "Cubic".