Hi - <div><br></div><div>I would really like to use a volume size greater than 256^3.</div><div><br></div><div>I know of all the options and reasons.</div><div><br></div><div>what I want is a white matter surface than has fairly evenly spaced nodes that are in approximate match to the voxels they enclose.</div>
<div><br></div><div>the reason is to seed, track and target using FSL surface tractography. the brain is a 250um macaque, and it&#39;s 320 voxels long unfortunately. the structural and DWI are the same resolution and in register and acpc aligned. such a shame to waste.</div>
<div><br></div><div>the freesurfer surfaces are imported into CARET and cross-registered to F99. but they keep their mesh if I want.</div><div><br></div><div>work with another sample showed that node numbers and even coverage over the WM/GM boundary had a signifiant effect on the FSL metrics, with the original FS WM surface and derivatives yielding the best results over other meshes like F99&#39;s or anything made with surefit directly from a downsampled version of the data. that data I could fit into 256^3.</div>
<div><br></div><div>I doubt that the nodes and voxels need to match perfectly, just ballpark and fairly even spacing.</div><div><br></div><div>if I used a downsampled volume at 500um to make surfaces in freesurfer, maybe I could upsmaple the surfaces afterwards? but then the pial and white would have to be resampled independently and that&#39;s probably no good.</div>
<div><br></div><div>If I have to resample the volume or apply a scaling transform the world won&#39;t end. In fact it will take less time to do probably. But it would be nice to use a larger size than 256^3 to take advantage of what I&#39;ve got.</div>
<div><br></div><div>best,</div><div><br></div><div>Colin, Sussex</div>