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<p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";
color:#1F497D'>Hello Chasan,<o:p></o:p></span></p>
<p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";
color:#1F497D'><o:p> </o:p></span></p>
<p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";
color:#1F497D'>The VTK DICOM readers already take the Rescale Slope and
Intercept values into account. The voxel values from DICOMReader are already
in HU so the offset should not be applied.<o:p></o:p></span></p>
<p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";
color:#1F497D'><o:p> </o:p></span></p>
<p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";
color:#1F497D'>The definition of Rescale Slope and Rescale Intercept can be
found in the DICOM Standard Part 3:<o:p></o:p></span></p>
<p class=MsoListParagraph style='text-indent:-.25in;mso-list:l0 level1 lfo1'><![if !supportLists]><span
style='font-size:11.0pt;font-family:Symbol;color:#1F497D'><span
style='mso-list:Ignore'>·<span style='font:7.0pt "Times New Roman"'>
</span></span></span><![endif]><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";
color:#1F497D'>Rescale Intercept (0028,1052)<o:p></o:p></span></p>
<p class=MsoNormal style='margin-left:.5in;text-autospace:none'><span
style='font-size:10.0pt;font-family:"Arial","sans-serif";color:#244061'>The
value b in relationship between stored values (SV) and the output units. Output
units = m*SV+b<o:p></o:p></span></p>
<p class=MsoListParagraph style='text-indent:-.25in;mso-list:l0 level1 lfo1'><![if !supportLists]><span
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</span></span></span><![endif]><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";
color:#1F497D'>Rescale Slope (0028,1053)<o:p></o:p></span></p>
<p class=MsoNormal style='margin-left:.5in;text-autospace:none'><span
style='font-size:10.0pt;font-family:"Arial","sans-serif";color:#244061'>m in
the equation specified in Rescale Intercept (0028,1052).<o:p></o:p></span></p>
<p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";
color:#1F497D'><o:p> </o:p></span></p>
<p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";
color:#1F497D'> --
Scott<o:p></o:p></span></p>
<p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";
color:#1F497D'><o:p> </o:p></span></p>
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<p class=MsoNormal><b><span style='font-size:10.0pt;font-family:"Tahoma","sans-serif"'>From:</span></b><span
style='font-size:10.0pt;font-family:"Tahoma","sans-serif"'> vtkusers-bounces@vtk.org
[mailto:vtkusers-bounces@vtk.org] <b>On Behalf Of </b>Chasan KIOUTSOUKMOUSTAFA<br>
<b>Sent:</b> Thursday, August 26, 2010 8:17 AM<br>
<b>To:</b> vtk mailList<br>
<b>Subject:</b> [vtkusers] Hounsfield Units of Human body part<o:p></o:p></span></p>
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<p class=MsoNormal>Hi all<br>
I'm trying to get iso surfaces of a human-body parts such as ( bone,
liver, muscle, skin) from DICOM datasets. For extraction of iso surfaces,
I'm using the MarchingCubes algorithm, and it needs the Hounsfield Unit
(HU) for extraction. I've found many <b>different</b> HU scales for human
body parts. My questions are;<br>
1. In DICOM tags, there is a value called "RescaleIntercept" what
exactly it is ? <br>
is it an offset of CT dataset ? and if it is for example -1000, so what is
the real HU of water for -1000 value ?<br>
<br>
HUofBone = (double)DicomReader->GetRescaleOffset() + 1200.0;<br>
boneExtractor->SetInputConnection(Dicomreader->GetOutputPort());<br>
boneExtractor->SetValue(0, HUofBone);<br>
<br>
In the given code, what GetRescaleOffset returns ? <br>
<br>
<br>
<br>
<br>
<br>
Chasan KIOUTSOUKMOUSTAFA<o:p></o:p></p>
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<p class=MsoNormal><br>
<br>
Chasan KIOUTSOUKMOUSTAFA<o:p></o:p></p>
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<p class=MsoNormal><span style='font-size:10.0pt;font-family:"Calibri","sans-serif"'><o:p> </o:p></span></p>
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