Hi Michael

by default we resample everything to 1mm isotropic. Different parts of our analysis are susceptible to changes in voxel size in different ways. I expect the volume stream resulting in the aseg is ok with relatively coarse voxels, but the surface stream will start to fail catastrophically as any voxel dimension gets close to or much above 2mm

cheers Bruce

On Tue, 4 Dec 2018, Michael ONeill wrote:

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Dear Freesurfer,

I’m enquiring about the known effect that pixel spacing has on the reconstructions and final volume estimates produces by Freesurfer. Specifically, is there a range of pixel spacing values that are necessary for accuracy? Secondly, if the pixel spacing and slice thickness are different values (i.e non-isometric voxels) does this have much of an effect on the final recon and volume estimates?

All the best,

Michael

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