[Rtk-users] SART vs FDK

[Simon Rit]

Thanks for the references. I'll check them and I'll let you know if I
detect a specific technique that should be used.
Don't hesitate if you have other questions,
Simon


On Wed, Apr 10, 2013 at 4:09 PM, MORY, CYRIL <Cyril.Mory at philips.com> wrote:

>  Thanks for your answer. I’ll crop the FDK and SART volumes to the FOV
> and see if initializing my algorithm this way yields better results.****
>
> Regarding ROI + TV, I don’t know the literature on the topic, but it turns
> out it’s quite abundant : a simple google search yields many results (
> http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3055906/,
> http://iopscience.iop.org/0031-9155/54/9/014) ****
>
> ** **
>
> Regards,****
>
> Cyril****
>
> *De :* simon.rit at gmail.com [mailto:simon.rit at gmail.com] *De la part de*Simon Rit
> *Envoyé :* mercredi 10 avril 2013 14:54
> *À :* MORY, CYRIL
> *Cc :* vilaoliva at creatis.insa-lyon.fr; rtk-users at openrtk.org
> *Objet :* Re: SART vs FDK****
>
> ** **
>
> Hi,
> This is a difficult question and I don't know the answer. I think what you
> observe is the famous edge artifact of SART reconstructions. My feeling is
> that that one can not trust values outside the FOV in any algorithm. I
> would mask the FOV if I were you, whatever the algorithm. On real data, I
> know it costs a bit of time but only a test with each initialization will
> give you an answer.****
>
> BTW, do you know any publication on ROI reconstruction+TV ?****
>
> Simon****
>
> ** **
>
> PS : I'm investigating the maling list issue, I'll let you know when I get
> an answer.****
>
> ** **
>
> On Wed, Apr 10, 2013 at 12:59 PM, MORY, CYRIL <Cyril.Mory at philips.com>
> wrote:****
>
> Hi Simon, Hi Marc,****
>
>  ****
>
> I’ve tried to send this mail to the mailing list, but it contains images,
> so a manual approval from the list’s manager is required. ****
>
> And last time I talked with Simon, he couldn’t find the interface to
> approve or reject the emails. So I forward it.****
>
>
> Regards,****
>
> Cyril ****
>
>  ****
>
> *De :* MORY, CYRIL
> *Envoyé :* mercredi 10 avril 2013 11:54
> *À :* rtk-users at openrtk.org
> *Objet :* SART vs FDK****
>
>  ****
>
> Hi,****
>
>  ****
>
> I’m wondering whether the reconstruction results I get with SART and FDK
> are normal or not. I’ve performed reconstructions of a moving Shepp and
> Logan phantom, using 308 projections equidistributed on a 360° circular
> trajectory. The phantom is fully contained in the FOV. I’ve used the
> default projection and back projection operators for both SART (30
> iterations of SART instead of the default 5) and FDK. And there are very
> noticeable differences outside the FOV, especially at the edges of the
> projection cone, where SART produces high errors while FDK doesn’t. ****
>
>  ****
>
> Is this a normal behavior ? I’m using these reconstructions to initialize
> an iterative algorithm, and my real data is truncated, so I’d prefer to use
> SART than FDK. These high errors outside the FOV make me hesitate, though.
> ****
>
>  ****
>
> SART :****
>
> ****
>
>  ****
>
> FDK : ****
>
> ****
>
>  ****
>
>  ****
>
> Regards,****
>
>  ****
>
>  ****
>
> ==========================================****
>
> Cyril Mory****
>
> PhD student at Philips Medisys and CREATIS****
>
>  ****
>
> Groupement Hospitalier Est****
>
> Hôpital Cardiologique Louis Pradel****
>
> Laboratoire CREATIS - Bât. B13****
>
> CNRS UMR5220, INSERM U1044, INSA-Lyon, Univ. Lyon 1****
>
> 28, Avenue du Doyen LEPINE****
>
> 69677 Bron cedex FRANCE****
>
>  ****
>
> Office : +33 4 72 35 74 12****
>
> Cell : +33 6 69 46 73 79****
>
>  ****
>
> ** **
>  ------------------------------
>
> The information contained in this message may be confidential and legally
> protected under applicable law. The message is intended solely for the
> addressee(s). If you are not the intended recipient, you are hereby
> notified that any use, forwarding, dissemination, or reproduction of this
> message is strictly prohibited and may be unlawful. If you are not the
> intended recipient, please contact the sender by return e-mail and destroy
> all copies of the original message.****
>
> ** **
>
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://www.creatis.insa-lyon.fr/pipermail/rtk-users/attachments/20130410/1b9b8fa4/attachment.htm>
-------------- next part --------------
A non-text attachment was scrubbed...
Name: image001.jpg
Type: image/jpeg
Size: 92933 bytes
Desc: not available
URL: <http://www.creatis.insa-lyon.fr/pipermail/rtk-users/attachments/20130410/1b9b8fa4/attachment.jpg>
-------------- next part --------------
A non-text attachment was scrubbed...
Name: image002.jpg
Type: image/jpeg
Size: 74939 bytes
Desc: not available
URL: <http://www.creatis.insa-lyon.fr/pipermail/rtk-users/attachments/20130410/1b9b8fa4/attachment-0001.jpg>