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Hi all,<br>
<br>
I know the question has already been asked but I can't find the answer
in GATE-Talk, so I ask it again... <span class="moz-smiley-s14"><span>
O:-) </span></span><br>
I simulated 6 hot spheres (R=1cm) in a warm cylinder (D=20cm, H=70cm).
I want a contrast of 5:1. So I did the following to define the activity
I wanted in each of the volumes:<br>
for the cylinder: 214.6MBq<br>
for each sphere: (5-1)x(214.6MBq/(pix10x10x70))x(4xpix1x1x1/3), eg.
(5-1)x(Cylinder Activity / Cylinder Volume) x (Sphere Volume)<br>
I used (5-1) and not 5 assuming there will be the annihilations from
the cylinder AND from the spheres at the sphere location.<br>
<br>
The problem is that I can't recover that contrast in the reconstructed
data. Can someone tell me if I did something wrong in the activity
setting?<br>
<br>
Thanks a lot,<br>
<br>
<div class="moz-signature">-- Corinne<br>
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<hr style="width: 100%; height: 2px;"><font
style="color: rgb(102, 102, 102);" size="-1">Corinne
J. Groiselle, PhD</font><font style="color: rgb(102, 102, 102);"
size="-1"><br style="font-family: times new roman,times,serif;">
</font></div>
<div
style="text-align: left; font-family: times new roman,times,serif; color: rgb(102, 102, 102);"><font
size="-1">Research instructor<br>
<br>
Division
of Nuclear Medicine / Department of Radiology <br>
University
of Massachusetts Medical School <br>
55 Lake
Avenue North<br>
Worcester, MA 01655<br>
USA<br>
<br>
<u>phone</u>:
(508)-856-6123 - <span style="text-decoration: underline;">fax</span>:
(508)-856-4572<br>
<u>e-mail</u>:
<a class="moz-txt-link-abbreviated" href="mailto:Corinne.Groiselle@umassmed.edu">Corinne.Groiselle@umassmed.edu</a> <br>
<u>professional
homepage</u>: <a class="moz-txt-link-freetext" href="http://users.umassmed.edu/corinne.groiselle">http://users.umassmed.edu/corinne.groiselle</a><br>
<u>personal
homepage</u>: <a class="moz-txt-link-freetext" href="http://corinne.groiselle.free.fr">http://corinne.groiselle.free.fr</a></font> </div>
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