Hello,
Thank you for responding. Is there a way to constrain the
normalization to be rigid body in SPM99? I could not find this option
in the manual. Again, thanks in advance.
Sunil
Alle Meije Wink wrote:
>Dear Sunil,
>
>There are certainly *ways* to do that, the question is what you want to
>do with it. You usually coregister an anatomical scan (hi-res) to an EPI
>scan (lo-res) to be able to overlay functional data on the anatomy. You
>cannot do this if the images have different dimensions. So you must
>either reslice the EPI scans (use the 512x512 matrix) after
>coregistering them to the anatomy, or reslice the anatomy (use the
>128x128 matrix) after coregistering it to an EPI scan (assuming the EPIs
>have been realigned).
>
>If you insist on reslicing the hi-res picture in the original
>dimensions, you can do that using the `normalise' function. You then
>need to change the bounding box and voxel size of the normalised image
>with the `defaults' option and normalise the hi-res image to the lo-res
>image. Use 6 degrees of freedom (3 rotations, 3 translations) and no
>nonlinear deformations. This amounts to (rigid-body) coregistration.
>Once again: be sure that you want to do this.
>
>Cheers,
>Alle Meije Wink
>
>> Hello,
>>
>> I had a question regarding coregistering two image volumes with
>> different matrix sizes. I have one hi res set of data with a matrix
>> size of 512 by 512 and a second low res set with a matrix size of 128
>> by 128. When I coregister the hi res data to the low res data, the
>> resliced hi res image is downsampled to 128 by 128. Is there any way
>> to keep the original resolution for the hi res data?
>>
>> Thanks in advance for any advice.
>>
>> Sunil
>--
>
>Brain Mapping Unit
>Dept. of Psychiatry
>University of Cambridge
>Addenbrooke's Hospital
>Cambridge CB2 2QQ
>
>Tel: +44 (0)1223 336963
>Fax: +44 (0)1223 336581
>
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