# Why is it that after I import the patient's CT file (in DICOM format), the image is not displayed completely but only shows as a slit?

**URL:** <https://discourse.slicer.org/t/why-is-it-that-after-i-import-the-patients-ct-file-in-dicom-format-the-image-is-not-displayed-completely-but-only-shows-as-a-slit/42165>\
**Category:** Support\
**Tags:** dicom\
**Created:** [March 16, 2025, 2:14am UTC](https://discourse.slicer.org/t/why-is-it-that-after-i-import-the-patients-ct-file-in-dicom-format-the-image-is-not-displayed-completely-but-only-shows-as-a-slit/42165 "2025-03-16T02:14:01Z")\
**Posts on this page:** 2\
**Page:** 1

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**Author:** ![kkzmcbb](https://avatars.discourse-cdn.com/v4/letter/k/f14d63/32.png) [@kkzmcbb](https://discourse.slicer.org/u/kkzmcbb)\
**Post date:** [March 16, 2025, 2:14am UTC](https://discourse.slicer.org/t/why-is-it-that-after-i-import-the-patients-ct-file-in-dicom-format-the-image-is-not-displayed-completely-but-only-shows-as-a-slit/42165/1 "2025-03-16T02:14:01Z")

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![image](https://us1.discourse-cdn.com/flex002/uploads/slicer/original/3X/9/9/99e155b726439fd5b4cc7bd80611425c704b94e7.jpeg)

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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 16, 2025, 2:22am UTC](https://discourse.slicer.org/t/why-is-it-that-after-i-import-the-patients-ct-file-in-dicom-format-the-image-is-not-displayed-completely-but-only-shows-as-a-slit/42165/2 "2025-03-16T02:22:07Z")

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This is a projection = a 2D image. It is not a 3D volume.

If you have hundreds of projection images like this then it is possible to reconstruct a 3D image from it, but reconstruction is a complex operation and - since you need very accurate information on the imaging geometry - usually only the manufacturer can do it.

You can ask the people who gave you this image to create a 3D reconstruction and send that to you, too.