> A simple question: if we work with neurological MR (left is left and right
> is right), Is the final statistical image in neurological convention (left
> is left and right is right) too? Thanks in advance,
By default, the images are flipped during spatial normalisation. Therefore,
unless the spm_defaults.m file has been modified appropriately, or you have
explicitly changed the defaults during the spm session, your images will be
flipped to radiological orientation.
If all your images are the same, then you can permenantly change the
behaviour of SPM99 by editing spm_defaults.m, changing:
% Orientation/position of images. Used as a starting estimate for
% affine normalisation.
%-----------------------------------------------------------------------
%sptl_Ornt = [0 0 0 0 0 0 1 1 1 0 0 0]; % Neurological Convention (R is R)
sptl_Ornt = [0 0 0 0 0 0 -1 1 1 0 0 0]; % Radiological Convention (L is R)
to:
% Orientation/position of images. Used as a starting estimate for
% affine normalisation.
%-----------------------------------------------------------------------
sptl_Ornt = [0 0 0 0 0 0 1 1 1 0 0 0]; % Neurological Convention (R is R)
%sptl_Ornt = [0 0 0 0 0 0 -1 1 1 0 0 0]; % Radiological Convention (L is R)
Best regards,
-John
--
Dr John Ashburner.
Wellcome Department of Cognitive Neurology.
12 Queen Square, London WC1N 3BG, UK.
tel: +44 (0)20 78337491 or +44 (0)20 78373611 x4381
fax: +44 (0)20 78131420
http://www.fil.ion.ucl.ac.uk/~john
mail: [log in to unmask]
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