Hi,
I have a brain segmentation problem.
Scanner: Siemens 3T Verio Sequence: MPrage, TR=1900ms, TE=2.45ms, TI=900ms, Voxel: 1x1x1mm, 192 sagittal slices.
Problem: The lay of dura mater between brain and skull is bright (See attached brain.jpg). As a result, the segmented brain.mgz has a "cap", and the pial surface and GM/WM surface will "leak" to the dura layer somewhere (see the red dots in surfaces.jpg). This happened to some places and needs a lot of manual work to remove the connection between the brain and dura.
I tried to increase the TR to 3000ms. Still some connection somewhere, although the results are much better. Anybody optimized the mprage sequence to minimize the problem?
Thank you.
XJ Kang
freesurfer@nmr.mgh.harvard.edu