# Tractography to Fiber Bundle to PLY mesh

**URL:** <https://discourse.slicer.org/t/tractography-to-fiber-bundle-to-ply-mesh/3235>\
**Category:** Support\
**Created:** [June 19, 2018, 10:53pm UTC](https://discourse.slicer.org/t/tractography-to-fiber-bundle-to-ply-mesh/3235 "2018-06-19T22:53:26Z")\
**Posts on this page:** 4\
**Page:** 1

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**Author:** ![Nicholas.jacobson](https://avatars.discourse-cdn.com/v4/letter/n/ba8739/32.png) [@Nicholas.jacobson](https://discourse.slicer.org/u/Nicholas.jacobson)\
**Post date:** [June 19, 2018, 10:53pm UTC](https://discourse.slicer.org/t/tractography-to-fiber-bundle-to-ply-mesh/3235/1 "2018-06-19T22:53:26Z")

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Hello,  
Can anyone run me through the process for converting a tractography to a fiber bundle. Trying to explort the vtk file of curves for our tractography model into a PLY mesh. However, it appears I need to convert this into a fiber bundle prior to converting to a mesh.

When I run the Tractography to PLY mesh I get an error that says 'None type object has no attribute ‘SetName’

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**Author:** ![ljod](https://sea2.discourse-cdn.com/flex002/user_avatar/discourse.slicer.org/ljod/32/652_2.png) [@ljod](https://discourse.slicer.org/u/ljod)\
**Post date:** [June 20, 2018, 1:46am UTC](https://discourse.slicer.org/t/tractography-to-fiber-bundle-to-ply-mesh/3235/2 "2018-06-20T01:46:16Z")

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It looks like this data may have been loaded as a model. Please load it into slicer (when you add data to Slicer or drag and drop it into slicer) as a FiberBundle.

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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:** [June 20, 2018, 2:01am UTC](https://discourse.slicer.org/t/tractography-to-fiber-bundle-to-ply-mesh/3235/3 "2018-06-20T02:01:00Z")

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@ljod FYI, you can define composite file extensions to give Slicer hint how to load a certain file type by default. For example, segmentations are saved as .nrrd files, but we use .seg.nrrd extension so that when we drag-and-drop a segmentation file to Slicer, it is offered to be loaded as “Segmentation” by default (instead of as a simple “Volume”). You could use a file extension such as .fb.ply to make the file loaded as FiberBundle by default (instead of “Model”).

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**Author:** ![ljod](https://sea2.discourse-cdn.com/flex002/user_avatar/discourse.slicer.org/ljod/32/652_2.png) [@ljod](https://discourse.slicer.org/u/ljod)\
**Post date:** [June 20, 2018, 2:12am UTC](https://discourse.slicer.org/t/tractography-to-fiber-bundle-to-ply-mesh/3235/4 "2018-06-20T02:12:47Z")

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That is great thank you. I didn’t know about this feature.