# Overlapped ROIs image and diffusion images

**URL:** <https://community.mrtrix.org/t/overlapped-rois-image-and-diffusion-images/555>\
**Category:** Uncategorized\
**Created:** [November 7, 2016, 11:05am UTC](https://community.mrtrix.org/t/overlapped-rois-image-and-diffusion-images/555 "2016-11-07T11:05:25Z")\
**Posts on this page:** 2\
**Page:** 1

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**Author:** ![Li\_Changhong](https://community.mrtrix.org/letter_avatar_proxy/v4/letter/l/8e8cbc/32.png) [@Li\_Changhong](https://community.mrtrix.org/u/Li_Changhong)\
**Post date:** [November 7, 2016, 11:05am UTC](https://community.mrtrix.org/t/overlapped-rois-image-and-diffusion-images/555/1 "2016-11-07T11:05:25Z")

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Dear MRtrix3 experts,  
Now I got an image with 30 ROIs based on registration procedures. When I used MRIcron to check the images, it perfectly overlapped the diffusion image. But when I opened same datasets using MRtrix3, the ROIs apparently moved a bit left. Does anyone happen the similar problem or any suggestions?  
Thanks in advance for your attention!  
Best regards,  
Changhong

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**Author:** ![rsmith](https://community.mrtrix.org/user_avatar/community.mrtrix.org/rsmith/32/2672_2.png) [@rsmith](https://community.mrtrix.org/u/rsmith)\
**Post date:** [November 16, 2016, 3:35am UTC](https://community.mrtrix.org/t/overlapped-rois-image-and-diffusion-images/555/2 "2016-11-16T03:35:44Z")

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Hi Changhong,

It’s difficult to tell what’s going on here; it depends a lot on exactly how both software viewers align the images they are displaying. _MRtrix3_ is the only one we have any control over though.

- Do the two images have the same transformation matrix? Sometimes viewer softwares ignore the transform of an overlay image and instead assume that the voxels of the two images align perfectly. `mrview` _doesn’t_ make this assumption, and so could therefore be highlighting an issue that’s worth looking into.

- Are you using the overlay tool in `mrview`, or simply flicking between images?

- Are you able to capture some screenshots to precisely demonstrate the issue, and also post the output of `mrinfo` for each of the images in question?

Cheers  
Rob