Just to add to this:
If you are trying to get registrations within-subject then you
probably don't want to use
non-linear registration unless you are expecting substantial
distortions. For the
within-subject case, 6 dof should be the *correct* degrees-of-freedom
to use, which
can be done with flirt.
Can you describe more fully in what way that are "not good".
Note that you can only successfully register images that show the
same structures
(albeit with different contrasts). So registering a CBF map (or ADC)
could be
problematic. It is more usual to use an image that is already
aligned (an example
functional or the b=0 weighting diffusion image) for the
registrations and then
transform these other images using the spatial transformation found
by the
previous registration.
I hope this is helpful.
All the best,
Mark
On 17 Dec 2007, at 09:56, Steve Smith wrote:
> Hi - FSL 4.0 includes the IRTK nonlinear registration tool; see the
> TBSS scripts for example usage. However you're on your own wrt
> getting this to work on multimodal data, as we've not had much
> experience on this with IRTK.
>
> The next release of FSL will include FNIRT, a generic nonlinear
> registration tool which seems to work really well.
>
> Cheers.
>
>
>
>
> On 14 Dec 2007, at 19:05, Ping Wang wrote:
>
>> Dear FSL users:
>>
>> I have data in this situation: each subject has images from
>> different modalities: T1,T2, ADC, CBF. Now I only consider one
>> subject, I want to register all other modilitiy images to T2
>> image. I know Flirt only do linear registration, I tested the
>> results by Flirt, some are not good. Should I use non-linear
>> registration? I am wondering which tool in FSL can do non-linear
>> registration? tbss?
>>
>> Thanks, Ping
>>
>> Windows Live Writer,支持离线撰写博客内容,随时随地想写就写。 立即
>> 使用!
>
>
> ----------------------------------------------------------------------
> -----
> Stephen M. Smith, Professor of Biomedical Engineering
> Associate Director, Oxford University FMRIB Centre
>
> FMRIB, JR Hospital, Headington, Oxford OX3 9DU, UK
> +44 (0) 1865 222726 (fax 222717)
> [log in to unmask] http://www.fmrib.ox.ac.uk/~steve
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