[Insight-users] ring artifacts in CT

[Mario Ceresa]

Hello Somi,
rings artefacts happen in a CT scan if one of the detectors is faulty
or out of calibration. The detector then gives the same erroneous
reading at each angle and the result is a visible circle in the image.

You can read about some methods to reduce them here:

http://www.iop.org/EJ/article/0031-9155/54/12/018/pmb9_12_018.pdf

I'm sorry but I'm not aware of any "pluggable" solution, and the
scanner will probably need a repair/recalibration.

Hope this helps,

Mario


On 28 April 2010 09:27, Sergio Vera <sergio.vera at alma3d.com> wrote:
> It seems to me,
> after seeing that image, my first thought is that some filtering based on
> fourier analysis might help.
> At least when dealing with 2D images.
>
> Regards
>
> On Tue, Apr 27, 2010 at 9:27 PM, somi <seesomi at gmail.com> wrote:
>>
>> Hi,
>> I have some CT images which are severely degraded by ring artifacts during
>> acquisition .
>> The ring artifact looks something like :
>> http://www.upstate.edu/radiology/rsna/ct/images/artifact4.jpg (not my image)
>> , its more severe in my images.
>>
>> Has anybody encountered similar artifacts ? Is there is any out of the box
>> way to remove them ?
>>
>> Regards,
>> Somi
>>
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>
>
>
> --
> Sergio Vera
>
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> _____________________________________
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>
> Kitware offers ITK Training Courses, for more information visit:
> http://www.kitware.com/products/protraining.html
>
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