Thank you
But my question is: can I (after performing TBSS scripts) compare subjects
with a different number of directions in their DTI? If the quality is
different - as you are saying - I think the answer is no.
Angela
>
> I can provide the following insight:1. The more diffusion directions, the
> better the dependent measure will be.2. You will have perform across-group
> analyses with FEAT.3. You should probably resample your original image to
> 1x1x1mm resolution before spatially normailizing to the MNI templae.Hope
> this helps.Christine
> > Date: Tue, 24 Jan 2012 12:40:50 +0100
>> From: [log in to unmask]
>> Subject: [FSL] TBSS some questions
>> To: [log in to unmask]
>>
>> Dear FSL experts,
>> I have some questions about TBSS for which I have not found answers in
>> the
>> mailing list.
>>
>> 1. Which is the influence of the number of directions on the quality of
>> TBSS?
>>
>> I have a set of DTI images with B0=800 and number of directions=16 and
>> another set with the same B0 and 32 directions.
>> I guess that probabilistic tracking is not reliable with only 16
>> directions, but what about TBSS? Can images of the two groups be
>> compared
>> with TBSS in some way?
>>
>> 2. During the TBSS procedure there is a registration to the standard
>> image
>> with resultion 1mm*1mm*1mm. This result in a very long time when
>> performing statistics with randomise. My original scanning resolution is
>> 2mm. Do you think that registration of the skeletonised images and mask
>> to
>> a 2mm resolution would impair the statistical analyses? Or is it a
>> feasable approach?
>>
>> Thank you for your help!
>>
>> Angela
>
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