[Insight-users] Brain Segmentation of inhomogeneous images

[a.bongers at mediri.com]

Hi,

I am trying to use a Bayes Classifier to segment white ang gray brain matter from MRI images. Works O.K. so far, but I have the problem that many 3D images have varying gray-values e.g. in within the white matter. Thats probably due to RF inhomognieties from the coil or the like. 
The problem is that due to these slowly varying intensities the segmentation mis-calssifies GM and WM e.g. in the back of the brain.

Has anybody a helpful idea to get better results ?
I was thinking about hig-pass filtering the images to homogenize the intensities.
Is there a high- or bandpass filter in itk ?

Thanks a lot!

André