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<p>Hi,</p>
<p>I assume you've read</p>
<p><a
href="http://wiki.opengatecollaboration.org/index.php/Users_Guide_V7.2:Readout_parameters_for_Radiotherapy_applications:_Actors#Fixed_Forced_Detection_CT">http://wiki.opengatecollaboration.org/index.php/Users_Guide_V7.2:Readout_parameters_for_Radiotherapy_applications:_Actors#Fixed_Forced_Detection_CT</a>?</p>
<p>It's scarce but there are a bunch of references we suggest to
understand the technique. The numbers are the expected signal in
the image. All contributions are summed in total which can be
decomposed in primary+secondary. Secondary (same as scatter) can
itself be decomposed in compton+rayleigh+fluorescence. flatfield
is available to compute the measured primary signal if there is no
object, this is useful for CT to apply the beer Lambert law.
attenuation is ln(flatfield/primary) to get the line integral,
i.e., the input of most CT reconstruction algorithms.</p>
<p>An alternative is to do pure monte carlo, see monteCarloCT.mac in
the same folder. I guess there are other options in Gate but I
don't know all the CT options in Gate. Please let me know if you
find some!</p>
<p>Hope this helps and let us know if/how we should complete the
"doc",</p>
<p>Simon<br>
</p>
<br>
<div class="moz-cite-prefix">On 02/09/2016 09:49, Lukas Gromann
wrote:<br>
</div>
<blockquote cite="mid:2F51EFFD-7854-4884-938E-85F6C34E9676@tum.de"
type="cite"> Dear all,
<div><br>
</div>
<div>I am currently learning how to use Gate for my PHD project in
medical x-rax imaging.</div>
<div><br>
</div>
<div>I would like to simulate the Compton scatter fraction in a
simple Thorax x-ray. I started by using the
example_CT/fixedForcedDetectionCT, which looks like the thing I
am looking for. Unfortunately I cannot find any documentation,
what is actually the content of the outputfiles created by the
FixedForcedDetection actor. What does the numbers in the various
images represent? What is the purpose of the flatfield file?</div>
<div>Any kind of additional documentation/information would be
very welcome! </div>
<div><br>
</div>
<div>On the other hand, is there maybe a much better approach to
determine Compton scatter fractions in my images than using the
FFD actor? </div>
<div><br>
</div>
<div>Thanks for your help, </div>
<div><br>
</div>
<div>Lukas </div>
<div><br>
</div>
<div apple-content-edited="true">
<div style="color: rgb(0, 0, 0); letter-spacing: normal;
orphans: auto; text-align: start; text-indent: 0px;
text-transform: none; white-space: normal; widows: auto;
word-spacing: 0px; -webkit-text-stroke-width: 0px; word-wrap:
break-word; -webkit-nbsp-mode: space; -webkit-line-break:
after-white-space;">
<div>----------------------------------------------------</div>
<div>Lukas Gromann</div>
<div><br>
</div>
<div>Lehrstuhl für Biomedizinische Physik (E17)<br>
Technische Universität München<br>
Boltzmannstrasse 11<br>
85748 Garching<br>
<br>
</div>
<div><a moz-do-not-send="true"
href="mailto:Lukas.Gromann@TUM.de">Lukas.Gromann@TUM.de</a></div>
<div><br>
</div>
<div>Tel.: 089-289/10905</div>
<div>Mobil: 017629718306</div>
</div>
</div>
<br>
<br>
<fieldset class="mimeAttachmentHeader"></fieldset>
<br>
<pre wrap="">_______________________________________________
Gate-users mailing list
<a class="moz-txt-link-abbreviated" href="mailto:Gate-users@lists.opengatecollaboration.org">Gate-users@lists.opengatecollaboration.org</a>
<a class="moz-txt-link-freetext" href="http://lists.opengatecollaboration.org/mailman/listinfo/gate-users">http://lists.opengatecollaboration.org/mailman/listinfo/gate-users</a></pre>
</blockquote>
<br>
<div class="moz-cite-prefix">On 02/09/2016 09:49, Lukas Gromann
wrote:<br>
</div>
<blockquote cite="mid:2F51EFFD-7854-4884-938E-85F6C34E9676@tum.de"
type="cite">
<meta http-equiv="Content-Type" content="text/html; charset=utf-8">
Dear all,
<div><br>
</div>
<div>I am currently learning how to use Gate for my PHD project in
medical x-rax imaging.</div>
<div><br>
</div>
<div>I would like to simulate the Compton scatter fraction in a
simple Thorax x-ray. I started by using the
example_CT/fixedForcedDetectionCT, which looks like the thing I
am looking for. Unfortunately I cannot find any documentation,
what is actually the content of the outputfiles created by the
FixedForcedDetection actor. What does the numbers in the various
images represent? What is the purpose of the flatfield file?</div>
<div>Any kind of additional documentation/information would be
very welcome! </div>
<div><br>
</div>
<div>On the other hand, is there maybe a much better approach to
determine Compton scatter fractions in my images than using the
FFD actor? </div>
<div><br>
</div>
<div>Thanks for your help, </div>
<div><br>
</div>
<div>Lukas </div>
<div><br>
</div>
<div apple-content-edited="true">
<div style="color: rgb(0, 0, 0); letter-spacing: normal;
orphans: auto; text-align: start; text-indent: 0px;
text-transform: none; white-space: normal; widows: auto;
word-spacing: 0px; -webkit-text-stroke-width: 0px; word-wrap:
break-word; -webkit-nbsp-mode: space; -webkit-line-break:
after-white-space;">
<div>----------------------------------------------------</div>
<div>Lukas Gromann</div>
<div><br>
</div>
<div>Lehrstuhl für Biomedizinische Physik (E17)<br>
Technische Universität München<br>
Boltzmannstrasse 11<br>
85748 Garching<br>
<br>
</div>
<div><a moz-do-not-send="true"
href="mailto:Lukas.Gromann@TUM.de">Lukas.Gromann@TUM.de</a></div>
<div><br>
</div>
<div>Tel.: 089-289/10905</div>
<div>Mobil: 017629718306</div>
</div>
</div>
<br>
<br>
<fieldset class="mimeAttachmentHeader"></fieldset>
<br>
<pre wrap="">_______________________________________________
Gate-users mailing list
<a class="moz-txt-link-abbreviated" href="mailto:Gate-users@lists.opengatecollaboration.org">Gate-users@lists.opengatecollaboration.org</a>
<a class="moz-txt-link-freetext" href="http://lists.opengatecollaboration.org/mailman/listinfo/gate-users">http://lists.opengatecollaboration.org/mailman/listinfo/gate-users</a></pre>
</blockquote>
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