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<p class="MsoNormal">Hello,<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">I was wondering if it would be possible to get information of exactly how the deformable registration field is defined, specifically for the daemons filter. Assuming we have a fixed CT and a moving CT of the same number of pixels in each
dimension, the deformable field could be defined as<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">‘To deformation field’<o:p></o:p></p>
<p class="MsoNormal">For each voxel in moving CT, the vectors point to the location this voxel should be mapped in the fixed CT<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">Or<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">‘From deformation field’<o:p></o:p></p>
<p class="MsoNormal">For each voxel in fixed CT, the vector points to the location in the moving CT from which we should grab and place here<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">In addition, each of these could be defined as either +/- depending on how you define the starting location of the pixel shifts. I am generating these deformation fields and saving them as VTK files, then applying them in my own implementation.
I have switched definitions and tried multiple ways to apply the deformation field, and no single method produces a result that is obviously correct or obviously wrong. Any information on how the deformation field is actually defined would be appreciated.
Thanks<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">James Armstrong, Ph.D.<o:p></o:p></p>
<p class="MsoNormal">PostDoctoral Fellow, Physics<o:p></o:p></p>
<p class="MsoNormal">Department of Radiation Oncology<o:p></o:p></p>
<p class="MsoNormal">University of Colorado School of Medicine<o:p></o:p></p>
<p class="MsoNormal">1665 Aurora Ct, MS F706<o:p></o:p></p>
<p class="MsoNormal">Aurora, CO 80045<o:p></o:p></p>
<p class="MsoNormal">720-848-0257<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
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