The min/max/etc are the voxel wise measures. When you use --accumulate, it sums all the voxels but does not divide by the number of voxels, so you get a number much larger than any one voxel doug

On 9/3/14 9:44 PM, SHAHIN NASR wrote:

Hi Surfers,

I want to measure the average amount of myelinations within my ROI(s),
I have already generated my myelination maps on surfaces (e.g. 

lh.myelin_ProjFrac0p5.nii ). Then I used mri_segstats as below:

mri_segstats --i lh.myelin_ProjFrac0p5.nii --slabel SBJ_001 lh lh.V1 --sum V1_Stats.txt --accumulate

but the numbers don't make any sense. For instance:

# ColHeaders Index SegId NVertices Area_mm2 StructName Mean StdDev Min Max Range 1 0 125261 82573.4 Seg0000 110280.4453 0.2922 -5.5000 51.0000 56.5000 2 1 1138 764.8 Seg0001 941.0988 0.1572 0.2675 1.4203 1.1527

How can mean=941.0988 when the max=1.4203 ???

Regards

Shahin Nasr

PhD in Cognitive Neuroscience Martinos Imaging Center, MGH Harvard Medical School

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