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Hi everybody,<br><br>
I´m dealing with a project of motion correction in 3D DCE-MRI series. Up
to now, I´ve tried several elastic registration algorithms, using MI and
different optimizers, and aplying multirresolution strategies. Since
there are intensity changes in my series along the time, I think that the
most appropriate approach is to use multimodality methods, in spite of I
only work with MRI.<br><br>
Every suggestion of my previous work will welcomed. <br><br>
Now, my questions:<br><br>
1) When I define a BSpline grid and obtain a transform from the
registration process, I achieve the registered image using the
<a href="http://www.itk.org/Doxygen/html/itkResampleImageFilter_8h-source.html">itk::ResampleImageFilter</a>.
But since I´m working with 3D and respiratory motion, I have some
difficulties in visualizing the deformation field and interpreting it. I
have tried with the Glyph option of the Paraview tool. Would you
recommend me another way?<br><br>
2) I have also tried the code of
<font face="Courier, Courier">Examples/Registration/DeformableRegistration2.cxx
</font> and
E<font face="Courier, Courier">xamples/Registration/DeformableRegistration5.cxx,
</font>so I have checked the possibilities of the
<font face="Courier, Courier" size=2>DemonsRegistrationFilter</font> and
the
<font face="Courier, Courier" size=2>LevelSetMotionRegistrationFilter.
</font>In principle it should not work because the dependence with the
voxel intensity and the histogram, but I got surprised because these
algorithms reached a good registration outcomes, correcting the position
of the input images. However:<br>
<x-tab> </x-tab>- The
resampled image looks absolutely fine about the position, but not about
the intensities, which seem to be adapted/very similar to those in the
reference image. Actually I am taking the spacing and origin of the fixed
image, but since I´m applying the output of the warping filter on the
moving image, shouldn´t be kept the intensities and corrected only the
position? I can´t understand how does the warping filter works, in spite
I have searched in the documentation...<br>
<x-tab> </x-tab>- On the
other hand, I write the deformation field as an image of vectors from the
output of the warping filter, and keep it in a .vtk file. But when I try
to visualize it as I did with the deformation fields of the resample
filter, I don´t get to see any field. How does this filter store the
vectors field and could it been visualized? Which are the differences
between the use of both of the filters? <br><br>
Thanks a lot in advance.<br>
Rosario<br><br>
<br><br>
<x-sigsep><p></x-sigsep>
<font face="Arial TUR, Helvetica">Rosario Sance Garzón<br>
Dpto. Ingeniería Electrónica<br>
E.T.S.I. Telecomunicación<br>
Avda. Ciudad Universitaria s/n<br>
E-28040 - Madrid (SPAIN)<br>
</font><font face="Eras Medium ITC">___________________________________________________</font>
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