# Get Segment Node contour by DRR metrix

**URL:** <https://discourse.slicer.org/t/get-segment-node-contour-by-drr-metrix/37604>\
**Category:** Support\
**Created:** [July 29, 2024, 8:45am UTC](https://discourse.slicer.org/t/get-segment-node-contour-by-drr-metrix/37604 "2024-07-29T08:45:00Z")\
**Posts on this page:** 6\
**Page:** 1

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**Author:** ![fqzhice](https://avatars.discourse-cdn.com/v4/letter/f/7bcc69/32.png) [@fqzhice](https://discourse.slicer.org/u/fqzhice)\
**Post date:** [July 29, 2024, 8:45am UTC](https://discourse.slicer.org/t/get-segment-node-contour-by-drr-metrix/37604/1 "2024-07-29T08:45:00Z")

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I segment bone and vessel, then run DRR registration and get matrix. Later I just want get bone contour in DRR projected plane and chagned it by manually, such as mouse move, rotation, how can i do this?

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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:** [July 29, 2024, 9:29am UTC](https://discourse.slicer.org/t/get-segment-node-contour-by-drr-metrix/37604/2 "2024-07-29T09:29:20Z")

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> [@fqzhice](#):
>
> then run DRR registration

What is “DRR registration” registration of 3D CT to a 2D x-ray image? Do you perform it in Slicer or in some other software?

If you want to get the contour of the projection of the bones then you can use the 3D view for that: render the bones without shading (either as a segmented model; or directly the CT volume using volume rendering) and set the view background to black.

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**Author:** ![fqzhice](https://avatars.discourse-cdn.com/v4/letter/f/7bcc69/32.png) [@fqzhice](https://discourse.slicer.org/u/fqzhice)\
**Post date:** [July 29, 2024, 10:32am UTC](https://discourse.slicer.org/t/get-segment-node-contour-by-drr-metrix/37604/3 "2024-07-29T10:32:26Z")

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I generated drr image by drrgenerator in Slicer to make registration of 3D CT to DSA.  
Then want to render bone contour in DRR projected/DSA plane. Doctors will rotate or move the vr image slightlly by mouse if necessary. Also bone contour will also re-projected again  
I will try according your suggestion  
Thanks very much!

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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:** [July 29, 2024, 11:48am UTC](https://discourse.slicer.org/t/get-segment-node-contour-by-drr-metrix/37604/4 "2024-07-29T11:48:25Z")

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If you use volume rendering then you can edit the opacity transfer function to emphasize bone edges.

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**Author:** ![fqzhice](https://avatars.discourse-cdn.com/v4/letter/f/7bcc69/32.png) [@fqzhice](https://discourse.slicer.org/u/fqzhice)\
**Post date:** [July 30, 2024, 3:36am UTC](https://discourse.slicer.org/t/get-segment-node-contour-by-drr-metrix/37604/5 "2024-07-30T03:36:43Z")

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Yea!  
I convert bone segment node to labelmap and render in volume rendering module

 ![image](https://us1.discourse-cdn.com/flex002/uploads/slicer/original/3X/3/b/3ba64cd81703313360f45b09e579c859ecf387b6.png)

This maybe can fulfill our requirement. but i cant do it segment module now  
The slicer main version is 5.4

This is philips product and i think is more better

 ![1722310697050](https://us1.discourse-cdn.com/flex002/uploads/slicer/original/3X/b/9/b94d5c1a1fcd1d458816d4083a9ecd31ed7552d0.jpeg)

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<div class="post-metadata">

**Author:** ![fqzhice](https://avatars.discourse-cdn.com/v4/letter/f/7bcc69/32.png) [@fqzhice](https://discourse.slicer.org/u/fqzhice)\
**Post date:** [July 30, 2024, 5:30am UTC](https://discourse.slicer.org/t/get-segment-node-contour-by-drr-metrix/37604/6 "2024-07-30T05:30:44Z")

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Thanks for your help @lassoan