Hello,
stripes in the residual variance sound like white pixel artefact.
Essentially that you get a spike in the k space data and it looks like
stripes when you do the Fourier tranfrom reconstruction. To remove
it, you just have to filter the k-space data if you have access to it.
Check with your physicist to see if that is the case. ANother way to
check it is to look through a movie loop of the time series and see if
you see the stripe pattern in some of the time points.
I hope that helps
-Luis
Quoting Torben Ellegaard Lund <[log in to unmask]>:
> Hi Sheeba
>
> What is your voxel size, are the voxels you use very long? I don't know
> how this would affect the RPV image in the extreme case, but first we need
> to know if your voxels are extreemly long.
>
> Best
> Torben
>
>
>> Thank you very much for the reply!
>>
>> The movement parameters look fine (within 1 mm, 1 degree)! What's
>> confusing is that we see stripes in RPV.img in all the subjects scanned
>> with this protocol.
>>
>> What information is contained in each voxel in RPV.img?
>>
>> The raw images look fine.
>>
>> In another study with isotropic voxels, we don't see such artifacts..
>>
>> Best Regards,
>> Sheeba
>>
>
>
>
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