When I run mri_info I get:

Volume information for /home/freesurfer4.4.0/subjects/corinna/ADNI/003_S_1057/mri/lh.white.projfrac.35.mgh
          type: MGH
    dimensions: 23334 x 1 x 5
   voxel sizes: 1.0000, 1.0000, 1.0000
          type: FLOAT (3)
           fov: 23334.000
           dof: 0
        xstart: -11667.0, xend: 11667.0
        ystart: -0.5, yend: 0.5
        zstart: -2.5, zend: 2.5
            TR: 3000.00 msec, TE: 3.61 msec, TI: 1000.00 msec, flip angle: 8.00 degrees
       nframes: 1
ras xform present
    xform info: x_r =  -1.0000, y_r =   0.0000, z_r =   0.0000, c_r =     5.5017
              : x_a =   0.0000, y_a =   0.0000, z_a =   1.0000, c_a =    11.5254
              : x_s =   0.0000, y_s =  -1.0000, z_s =   0.0000, c_s =     0.0000

talairach xfm : /home/freesurfer4.4.0/subjects/corinna/ADNI/003_S_1057/mri/transforms/talairach.xfm
Orientation   : LIA
Primary Slice Direction: coronal

voxel to ras transform:
               -1.0000   0.0000   0.0000 11672.5020
                0.0000   0.0000   1.0000     9.0254
                0.0000  -1.0000   0.0000     0.5000
                0.0000   0.0000   0.0000     1.0000

voxel-to-ras determinant -1

ras to voxel transform:
               -1.0000   0.0000   0.0000 11672.5020
               -0.0000  -0.0000  -1.0000     0.5000
               -0.0000   1.0000  -0.0000    -9.0254
                0.0000   0.0000   0.0000     1.0000



On Fri, Jun 4, 2010 at 9:58 AM, Bruce Fischl <fischl@nmr.mgh.harvard.edu> wrote:
if you run mri_info on the .mgh file does it return reasonable looking values?

On Fri, 4 Jun 2010, corinna bauer wrote:

Hi Bruce,
I am having trouble getting my .mgh files to open in MRIread. I get the
following error message.

ERROR: could not open /home/freesurfer4.4.0/
subjects/corinna/ADNI/003_S_1057/mri/lh.white.projfrac35.mgh for reading
ERROR: loading
/home/freesurfer4.4.0/subjects/corinna/ADNI/003_S_1057/mri/lh.white.projfrac35.mgh
as MGH
??? Attempt to reference field of non-structure array.

Error in ==> gwRatio at 24
      gwratio.vol = gray.vol / white.vol;


here's my .m file

function gwRatio

rootdir = '/home/freesurfer4.4.0/subjects/corinna/ADNI';
paths=dir([rootdir,'/*']);

numel(paths)
     num = numel(paths);

for ii = 1:num
  if(paths(ii).isdir && ~strcmp(paths(ii).name,'.') &&
~strcmp(paths(ii).name,'..'))

      graypath=
fullfile(rootdir,paths(ii).name,'mri/lh.white.projfrac35.mgh');
      whitepath =
fullfile(rootdir,paths(ii).name,'mri/lh.white.projdist.neg1.mgh');
      outpath = fullfile(rootdir,paths(ii).name,'mri/lh.gwratio.mgh');

      fprintf('----- Processing %i of %i -----\n', ii, num);
      fprintf('gray: %s\n', graypath);
      fprintf('white: %s\n', whitepath);
      fprintf('out: %s\n', outpath);

      gray = MRIread(graypath);
      white = MRIread(whitepath);
      gwratio = gray;
      gwratio.vol = gray.vol / white.vol;
      MRIwrite(gwratio, outpath);
  end
end

corinna



The information in this e-mail is intended only for the person to whom it is
addressed. If you believe this e-mail was sent to you in error and the e-mail
contains patient information, please contact the Partners Compliance HelpLine at
http://www.partners.org/complianceline . If the e-mail was sent to you in error
but does not contain patient information, please contact the sender and properly
dispose of the e-mail.