# Plastimatch DRR Generation Export

**URL:** <https://discourse.slicer.org/t/plastimatch-drr-generation-export/28455>\
**Category:** Support\
**Created:** [March 19, 2023, 6:27pm UTC](https://discourse.slicer.org/t/plastimatch-drr-generation-export/28455 "2023-03-19T18:27:58Z")\
**Posts on this page:** 4\
**Page:** 1

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**Author:** ![crissina0905](https://avatars.discourse-cdn.com/v4/letter/c/71e660/32.png) [@crissina0905](https://discourse.slicer.org/u/crissina0905)\
**Post date:** [March 19, 2023, 6:27pm UTC](https://discourse.slicer.org/t/plastimatch-drr-generation-export/28455/1 "2023-03-19T18:27:58Z")

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Hi everyone,

I am trying to generate 2D digitally reconstructed radiographs from 3D CT scans of the abdomen using the ‘Plastimatch DRR generation’ module. When the DRR renders in the software it looks like the image below.

 ![image](https://us1.discourse-cdn.com/flex002/uploads/slicer/original/3X/c/1/c1c4b024fff7129e20852a47e54aafee830eafbf.jpeg)

However, when I export it, everything appears white:

 ![image](https://us1.discourse-cdn.com/flex002/uploads/slicer/original/3X/f/f/ffec5d85b0f910433ca69d2e623c4d38a9db034f.jpeg)

Does anybody know how I can fix this? Also, in the top right panel in the first image, the projection and the CT image do not have the same orientation, why is that?

FInally, I would be very grateful if I can have some guidance on how to select the SAD, SID and isocenter values.

Thanks for your help!

Cristina

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**Author:** ![lassoan](https://sea2.discourse-cdn.com/flex002/user_avatar/discourse.slicer.org/lassoan/32/13_2.png) [@lassoan](https://discourse.slicer.org/u/lassoan)\
**Post date:** [March 19, 2023, 7:46pm UTC](https://discourse.slicer.org/t/plastimatch-drr-generation-export/28455/2 "2023-03-19T19:46:33Z")

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The images in your screenshots look good. You probably want to adjust the window/level in your viewer to avoid the too bright appearance.

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**Author:** ![Mik](https://avatars.discourse-cdn.com/v4/letter/m/958977/32.png) [@Mik](https://discourse.slicer.org/u/Mik)\
**Post date:** [March 20, 2023, 8:26am UTC](https://discourse.slicer.org/t/plastimatch-drr-generation-export/28455/3 "2023-03-20T08:26:39Z")

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> [@crissina0905](#):
>
> Also, in the top right panel in the first image, the projection and the CT image do not have the same orientation, why is that?

The DRR module expects that CT volume has as a standard DICOM orientation. You can change the volume orientation in `Transforms` module.

> [@crissina0905](#):
>
> FInally, I would be very grateful if I can have some guidance on how to select the SAD, SID and isocenter values.

I would recommend to use `External Beam Planning`, `Beams`, `DRR Image Computation` modules in the `Radiotherapy` subsection.

- External Beam Planning - create a dummy plan and setup isocenter point or segmentation node for the particular ROI;
- Beams - setup RTBeam node parameters;
- DRR Image Computation - module to compute DRR image with better UI, that module uses the `DRR generation` modules as a basis.

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**Author:** ![gcsharp](https://sea2.discourse-cdn.com/flex002/user_avatar/discourse.slicer.org/gcsharp/32/863_2.png) [@gcsharp](https://discourse.slicer.org/u/gcsharp)\
**Post date:** [March 20, 2023, 3:22pm UTC](https://discourse.slicer.org/t/plastimatch-drr-generation-export/28455/4 "2023-03-20T15:22:01Z")

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The SAD and SID depend on the equipment, so you will need to check the user manual. In RT, typical values would be SAD 100 cm and SID 150 cm.