I think this will depend on the age of your subjects and the nature of the acquisition that you are taking.
Because there are often many differences in contrast due to absent and partial myelination then the settings for adult brains often don't work that well. One thing that others have tried is to increase the number of classes that you use (from the original 3 to something higher, even up to 8) in order to capture the differently myelinated tissues. So try this and see if it helps.
All the best,
On 23 Jan 2014, at 17:31, Mojdeh Zamyadi <[log in to unmask]> wrote:
> Hi all,
> I was wondering if anyone has used FAST for Grey/White matter segmentation of paediatric brains? Is there a set of parameters that works best with young brains?