ok, I will do that.
On Feb 5, 2009, at 12:45 PM, Silviu Podariu wrote:
> 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
>
>
Arne Ekstrom, Ph.D.
Postdoctoral Fellow
Center For Cognitive Neuroscience, Semel Institute
University of California, Los Angeles
ph: 310.794.9360
fax: 310.794.7406
http://airto.hosted.ats.ucla.edu/~aekstrom/
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