# Slicer loads wrong image spacing

**URL:** <https://discourse.slicer.org/t/slicer-loads-wrong-image-spacing/453>\
**Category:** Support\
**Created:** [June 7, 2017, 4:35pm UTC](https://discourse.slicer.org/t/slicer-loads-wrong-image-spacing/453 "2017-06-07T16:35:07Z")\
**Posts on this page:** 1\
**Showing post:** 4

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**Author:** ![pieper](https://sea2.discourse-cdn.com/flex002/user_avatar/discourse.slicer.org/pieper/32/8_2.png) [@pieper](https://discourse.slicer.org/u/pieper)\
**Post date:** [June 7, 2017, 8:23pm UTC](https://discourse.slicer.org/t/slicer-loads-wrong-image-spacing/453/4 "2017-06-07T20:23:03Z")

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Hi -

PixelSpacing should always give the in-plane sizes in mm. Be sure it is in a valid dicom format of two DS values (basically decimal strings separated by backslash).

If you use dcmdump from dcmtk it should look something like this:

```
(0028,0030) DS [1.000000e+00\1.000000e+00] # 26, 2 PixelSpacing
```

The out of plane spacing is defined by the distance between the ImagePositionPatient of adjacent slices, not by the SliceThickness, which can be different for a variety of reasons.

If Slicer (or ITK) can’t parse what your file contains you could end up with spacings of 1,1,1.

It’s a slightly different context, but this blog post gives you some background and context:

> **[How Thick am I? The Sad Story of a Lonely Slice.](http://dclunie.blogspot.com/2013/10/how-thick-am-i-sad-story-of-lonely-slice.html)**
>
> Summary: Single slice regions of interest with no multi-slice context or interval/thickness information may need to be reported as area only...

HTH,  
Steve

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