# How can I register the MRI and CT quickly and accurately?

**URL:** <https://discourse.slicer.org/t/how-can-i-register-the-mri-and-ct-quickly-and-accurately/1102>\
**Category:** Support\
**Created:** [September 22, 2017, 1:05pm UTC](https://discourse.slicer.org/t/how-can-i-register-the-mri-and-ct-quickly-and-accurately/1102 "2017-09-22T13:05:55Z")\
**Posts on this page:** 3\
**Page:** 1

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**Author:** ![hongtao\_zhang](https://sea2.discourse-cdn.com/flex002/user_avatar/discourse.slicer.org/hongtao_zhang/32/170_2.png) [@hongtao\_zhang](https://discourse.slicer.org/u/hongtao_zhang)\
**Post date:** [September 22, 2017, 1:05pm UTC](https://discourse.slicer.org/t/how-can-i-register-the-mri-and-ct-quickly-and-accurately/1102/1 "2017-09-22T13:05:56Z")

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Operating system:windows 10  
Slicer version: 4.6.2  
Expected behavior: register MRI and CT image accurately  
Actual behavior: I can’t use landmark registration to register the image quickly and accurately.  
[https://drive.google.com/drive/u/0/folders/0B8dO8C1bNC7AT0tmWFd6M1BRTEE](https://drive.google.com/drive/u/0/folders/0B8dO8C1bNC7AT0tmWFd6M1BRTEE)

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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:** [September 22, 2017, 1:30pm UTC](https://discourse.slicer.org/t/how-can-i-register-the-mri-and-ct-quickly-and-accurately/1102/2 "2017-09-22T13:30:24Z")

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What was the problem? How did you try to register?

If the images don’t overlap in their initial position then it may be difficult to mark the points on them. If that’s the case, I would recommend to align the images manually using Transforms module to make them overlap .

Note that for prostate US/MRI registration Slicer has fully automatic registration modules. @cpinter might be able to give more details.

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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:** [September 22, 2017, 1:37pm UTC](https://discourse.slicer.org/t/how-can-i-register-the-mri-and-ct-quickly-and-accurately/1102/3 "2017-09-22T13:37:59Z")

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Since this is the same object in two modalities just a doing a rigid registration with BRAINSFit gave a good result.

 ![image](https://us1.discourse-cdn.com/flex002/uploads/slicer/original/3X/b/8/b8f0893bb6f823e909dc87633fd67646d132ab59.png)