Sean-
One option is to use the command "Transfer ROI to new coordinates" from
MRIcro's "ROI" menu. You will be asked to:
1.) select the ROI file.
2.) select a hdr file for the original ROI coordinates.
3.) select a hdr file with the new coordinates.
MRIcro will then create a new ROI that will be matched to the new
coordinates. You can then use MRIcro's "Export ROI as Analyze image" (also
in the ROI menu) to convert the new ROI to analyze format.
Note that this algorithm uses a simple nearest neighbor estimation. Other,
more clever reslicing techniques would probably use linear, sinc or chirp-Z
interpolations. This is probably not a huge issue to you, as your image is
binary and you are making it smaller rather than larger. However, other
algorithms may look a bit less chunky.
-chris
At 09:59 12/11/2001 +0000, Sean Colloby wrote:
>Dear SPM'ers
>
>I have created a cerebellum ROI map in MNI space from the SPM99 SPECT
>template using MRIcro. I am wishing to apply this map to my I-123 QNB SPECT
>images which
>are also in the standard space. Unfortunately, my ROI map has dimensions
>(91x109x91) and I want to apply them to standard images of dimension
>46x55x46. I
>have converted the ROI map into Analyze format and subsequently tried to
>change the image dimensions from (91x109x91) to (46x55x45) without any
>success. Is there
>anybody who can suggest a way to get around this problem?
>
>Many of you will be thinking, why don't you just create a ROI map of the
>cerebellum directly from the standard QNB image. The thing is there is no
>specific
>uptake in the cerebellum with these type of images but I am wishing to get a
>handle of the non-specific binding in the cerebellum. So my logic was to
>produce
>a ROI map of the cerebellum from the HMPAO SPECT template and apply this to
>the standard QNB images.
>
>Any suggestions would be gratefully received.
>
>Cheers
>
>Sean Colloby
>Research Associate
>Imaging Research Group
>Institute for Ageing and Health
>Wolfson Research Centre
>Newcastle General Hospital
>Newcastle-upon-Tyne
>NE4 6BE
>UK
>
>Tel: +44 (0) 191 256 3372
>Fax: +44 (0) 191 219 5051
>email: [log in to unmask]
__________________________________________
Dr. Chris Rorden
Department of Psychology
University of Nottingham
Nottingham NG7 2RD, UK
Tel: +44 [0]115-951-5294
Fax: +44 [0]115-951-5324
http://www.psychology.nottingham.ac.uk/staff/cr1/
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