Hello,
Somebody in the radiology department mentioned to us that our
tractography images (got them in diff and struct spaces) could be made
to look nicer if we used "zero filling", and I am trying to figure out
what that may be.
I looked at some FSL-dti sites for such a practice and I did not find
it, except for a mention in the e-mail list, message 8590 quoted
below. Do you know of such a practice? Is it useful/common in
dti-tractography?
In case we just wish to try it, this must be done using the MRI
scanner, right? (i.e. not with some of the FSL/other tools)
Thank you,
Silviu
-------------------- part of message 8590 : -----------------------
Thanks Peter,
Right now, we are using 128x128 scan matrix, 320mm FOV and 2.5mm thickness.
So scan voxel is 2.5x2.5x2.5 mm3. But the pixel spacing is 1.25x1.25 for the
acquired image since its size is 256x256, it is no longer isotropic (is this
correct?). If we need the 2.5x2.5x2.5 mm3 voxel for acquired images, should
we should set scan FOV to 640mm?
Wayne
On 8/21/06 9:25 AM, "Peter Kochunov" <[log in to unmask]> wrote:
> They are doing zero filling of k-space, which is equivalent to sinc
> interpolation.
> This won't degrade the resolution.
> pk
> ----- Original Message -----
> From: "Wayne Su" <[log in to unmask]>
> To: <[log in to unmask]>
> Sent: Monday, August 21, 2006 10:47 AM
> Subject: Re: [FSL] DTI resolution
>
>
>> Hi Peter,
>>
>> One more question about DTI protocol: our technician uses 128x128 scan
>> matrix on GE scanner. But reconstructed image sizes are 256x256. So the
>> scanner should have one interpolation method to get high-resolution
>> images.
>> We are not sure why this happened on GE scanner, we expected the image
>> sizes
>> should be 128x128. Does this ruin the DTI quality as the general
>> interpolation is not good for DTI vectors?
>>
>> Regards,
>> Wayne
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