# Mirroring 3D-data and calculate mismatch between lef&right side

**URL:** <https://discourse.slicer.org/t/mirroring-3d-data-and-calculate-mismatch-between-lef-right-side/12574>\
**Category:** Support\
**Created:** [July 16, 2020, 12:53pm UTC](https://discourse.slicer.org/t/mirroring-3d-data-and-calculate-mismatch-between-lef-right-side/12574 "2020-07-16T12:53:21Z")\
**Posts on this page:** 8\
**Page:** 1

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**Author:** ![Bernardo](https://avatars.discourse-cdn.com/v4/letter/b/c0e974/32.png) [@Bernardo](https://discourse.slicer.org/u/Bernardo)\
**Post date:** [July 16, 2020, 12:53pm UTC](https://discourse.slicer.org/t/mirroring-3d-data-and-calculate-mismatch-between-lef-right-side/12574/1 "2020-07-16T12:53:21Z")

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Hello  
I found out that it is possible to mirror 3D data of a CT scan, so that i.e. the right side matches the left side in uninjuried extremities. Is it also possible to calculate the mismatch between both sides (in percentage terms) in a selected area of the scan? For example, a patient with distal radius fracture on the right side, CT scan of both sides available (left side not injured): dislocation/malunion of the right side is xx %?  
Thanks for your help!

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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 16, 2020, 1:43pm UTC](https://discourse.slicer.org/t/mirroring-3d-data-and-calculate-mismatch-between-lef-right-side/12574/2 "2020-07-16T13:43:43Z")

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You can use Surface toolbox module to mirror a model, then align using SlicerIGT extension’s Fiducial registration wizard module. You can compute mismatch (surface distance) using “ModelToModelDistance” extension.

If you have the corresponding CT image, then you can view differences in the images, too, by mirroring the volume using Transforms module (applying a transform to the volume where you change one of the 1.0 values in the diagonal to -1.0) and then apply the same transform as you applied to the segmented model.

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**Author:** ![J\_Deng](https://sea2.discourse-cdn.com/flex002/user_avatar/discourse.slicer.org/j_deng/32/8020_2.png) [@J\_Deng](https://discourse.slicer.org/u/J_Deng)\
**Post date:** [September 6, 2020, 2:18am UTC](https://discourse.slicer.org/t/mirroring-3d-data-and-calculate-mismatch-between-lef-right-side/12574/3 "2020-09-06T02:18:20Z")

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Any possibility of showing a screen shot about mirroring images [or reversing a sequence]? I tried changing the numbers from 1 to -1, but the 3D view moved around instead of being mirrored. My particularly needs for this is because the original slices were converted in a reversed order, resulting in the left side of the body parts being displayed on the right, and vice versa. Many thanks.

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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:** [September 6, 2020, 5:12am UTC](https://discourse.slicer.org/t/mirroring-3d-data-and-calculate-mismatch-between-lef-right-side/12574/4 "2020-09-06T05:12:16Z")

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You might find Surface Toolbox module simpler to use. Create a new node for output, select Mirror, check the mirror axis, then click Apply.

 ![image](https://us1.discourse-cdn.com/flex002/uploads/slicer/original/3X/5/d/5d1997790d17f228d5001c9b142c33220037243b.jpeg)

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**Author:** ![J\_Deng](https://sea2.discourse-cdn.com/flex002/user_avatar/discourse.slicer.org/j_deng/32/8020_2.png) [@J\_Deng](https://discourse.slicer.org/u/J_Deng)\
**Post date:** [September 6, 2020, 5:12pm UTC](https://discourse.slicer.org/t/mirroring-3d-data-and-calculate-mismatch-between-lef-right-side/12574/5 "2020-09-06T17:12:57Z")

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![3d-slicer-mirror](https://us1.discourse-cdn.com/flex002/uploads/slicer/original/3X/8/c/8cf5d11172973d2c0adfbda6eff324c634fe73f9.png)  
Many thanks, Andras, for prompt reply as usual.

Tried using the latest preview 4.11.0-2020-08-29 r29335 / 0311336 , after hitting Apply and it showed Done, it did not appear to have mirrored [or changed] anything on the screen [x, y, z all tried]. Also, in “Input model”, I could not type a name, but after “Create a new model as …” in the Output model, I could go back to choose Model\_1.

Tried using formal release 4.10 … but because my segmentation was created on 4.11, I could not open it as it was displayed on 4.11 .

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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:** [September 6, 2020, 5:19pm UTC](https://discourse.slicer.org/t/mirroring-3d-data-and-calculate-mismatch-between-lef-right-side/12574/6 "2020-09-06T17:19:44Z")

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Surface Toolbox module operates on model nodes. You need to export the segmentation node to model node by right-clicking on it in Data module.

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<div class="post-metadata">

**Author:** ![J\_Deng](https://sea2.discourse-cdn.com/flex002/user_avatar/discourse.slicer.org/j_deng/32/8020_2.png) [@J\_Deng](https://discourse.slicer.org/u/J_Deng)\
**Post date:** [September 6, 2020, 6:14pm UTC](https://discourse.slicer.org/t/mirroring-3d-data-and-calculate-mismatch-between-lef-right-side/12574/7 "2020-09-06T18:14:21Z")

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Got you and succeeded. Thanks a lot.  
As you are so knowledgeable [and a bit off-the thread], could you redirect me to the latest progress in importing GE 4D ultrasound data either from its adult cardiac studies [E9 and E95] or from its fetal cardiac studies [E10]? Info about either direct import or indirect import via TomTec or EchoPac would greatly appreciated!

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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:** [September 6, 2020, 6:27pm UTC](https://discourse.slicer.org/t/mirroring-3d-data-and-calculate-mismatch-between-lef-right-side/12574/8 "2020-09-06T18:27:32Z")

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4D ultrasound import from GE systems now works well, using [Image3dAPI implemented in SlicerHeart extension](https://github.com/SlicerHeart/SlicerHeart#open-image3d-api).