Hi,
I would firstly recommend that for paediatric images you might want to create your
own template rather than use the standard MNI152.
As for the BOLD to high_res registration, then the other options depend on the
quality of your images. If there is substantial geometric distortion or signal loss
then one option is to create cost function masks (by hand) that would mask out
the regions of distortion or signal loss. Alternative cost functions can be used,
and optimising the brain extraction (possibly by hand) can also be useful.
None of these options can be run through the FEAT GUI - they all require
running the registration tools separately (FLIRT in the case of BOLD to high_res)
and, after you get a good result you can update the FEAT registration by running
"updatefeatreg" in the appropriate FEAT directory after replacing the crucial
transformation matrices (example_func2highres.mat and/or highres2standard.mat
and highres2standard_warp).
I hope this helps you.
All the best,
Mark
On 3 Feb 2012, at 16:20, Mojdeh Zamyadi wrote:
> Hi there,
>
> Sorry to add my question here, I didn't want to start a new thread since I thought my question is related to this post. I also have difficulty figuring out what would be the best way to register BOLD -> high_res ANAT -> MNI152 images. I have BOLD images of paediatric brains with the resolution of 2.29x2.29x5, anatomical resolution ranging from 0.5 to 1 mm (isotropic). I've used FLIRT to do BOLD -> high_res ANAT and the results are not very good in some cases, I sometimes see up to 3 slices of miss-registration after resampling. Also, I have done the high_res ANAT to MNI using both FLIRT and FNIRT but am not sure which would be the best approach for paediatric brain. I have used different combinations of FNIRT parameters but it the registered image seems to be too deformed in some cases, I was wondering if you have a set of parameters that work best for paediatric brain.
>
> Unfortunately, the field maps were not acquired at the time of imaging, but you mentioned there are other ways to improve the registration and I was wondering what those would be.
>
> Thanks so much for your help,
> -Mojdeh
>
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