[Insight-users] Suggestion(s) for rigid registration

[Martin Kavec]

Hi,

I am rather new to image registration and would like to hear your opinion
to solve the problem the most efficiently. Before I would start with ITK
implementation, I tried to rigid register the images using FSL or
Analyze6, but these failed.

I would very much appreciate if you have a look at the volumes. You can
grab them here :

http://www.uku.fi/~kavec/volumes.tar.bz2

The volumes are in Analyze format tar-ed and bz2-ed. The images are 3D
MRI volumes of the subject scanned on a different field strengths. The
reference.* is a high-field T1-weighted and I suppose its fine. However,
floating.* is a low-field "T1-weighted", lower resolution. In addition,
large surface coil was used (note high signal on the top of the skull and
nose), plus the image is by default (by manufacturer) masked using
elliptical mask.

The problems I can see, which cause a registration failure are large
signal intensities variation due to surface coil and the elliptical mask.

Questions:

1. Correcting the signal bias (using itkMRIBiasFieldCorrectionFilter)
   would increase the chances for better registration outcome?

2. Normalized mutual information would be optimal cost function, taking
   into account elliptical mask?

3. Any other suggestions (ITK optimizer, ...)?


Thanks for help in advance.

Martin