# FileFormatError when loading PET CT

**URL:** <https://discourse.slicer.org/t/fileformaterror-when-loading-pet-ct/20579>\
**Category:** Support\
**Tags:** pet, petct\
**Created:** [November 11, 2021, 1:53pm UTC](https://discourse.slicer.org/t/fileformaterror-when-loading-pet-ct/20579 "2021-11-11T13:53:46Z")\
**Posts on this page:** 4\
**Page:** 1

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**Author:** ![rbumm](https://sea2.discourse-cdn.com/flex002/user_avatar/discourse.slicer.org/rbumm/32/9404_2.png) [@rbumm](https://discourse.slicer.org/u/rbumm)\
**Post date:** [November 11, 2021, 1:53pm UTC](https://discourse.slicer.org/t/fileformaterror-when-loading-pet-ct/20579/1 "2021-11-11T13:53:47Z")

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Hi,  
I would like to load PET CT images into Slicer 3.13, DICOM import works, but clicking the axial 512x512 PET image series results in:

```auto
Could not read scalar volume using GDCM approach. Error is: FileFormatError
Loading with imageIOName: DCMTK
Could not read scalar volume using DCMTK approach. Error is: FileFormatError
Could not load: 552: TK axial as a Scalar Volume

```

The PETDICOMExtension is installed. Any ideas?

Thank you.

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<div class="post-metadata">

**Author:** ![rbumm](https://sea2.discourse-cdn.com/flex002/user_avatar/discourse.slicer.org/rbumm/32/9404_2.png) [@rbumm](https://discourse.slicer.org/u/rbumm)\
**Post date:** [November 11, 2021, 2:30pm UTC](https://discourse.slicer.org/t/fileformaterror-when-loading-pet-ct/20579/2 "2021-11-11T14:30:36Z")

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Addition:  
There is a b/w 128x128 PET image series with modality “PT” that can be loaded, but the colored PET-CT images with modality “OT” can not.

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<div class="post-metadata">

**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:** [November 11, 2021, 2:58pm UTC](https://discourse.slicer.org/t/fileformaterror-when-loading-pet-ct/20579/3 "2021-11-11T14:58:11Z")

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“OT” modality means other, it is an unidentified blob of data. It can be safely ignored.

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<div class="post-metadata">

**Author:** ![rbumm](https://sea2.discourse-cdn.com/flex002/user_avatar/discourse.slicer.org/rbumm/32/9404_2.png) [@rbumm](https://discourse.slicer.org/u/rbumm)\
**Post date:** [November 11, 2021, 5:46pm UTC](https://discourse.slicer.org/t/fileformaterror-when-loading-pet-ct/20579/4 "2021-11-11T17:46:23Z")

</div>

That makes sense, and I am now able to display the “TK AC” b/w series and the “TK 3D” color series.