# Undo button for mistakes in segmentation

**URL:** <https://discourse.slicer.org/t/undo-button-for-mistakes-in-segmentation/31486>\
**Category:** Support\
**Created:** [August 31, 2023, 10:43pm UTC](https://discourse.slicer.org/t/undo-button-for-mistakes-in-segmentation/31486 "2023-08-31T22:43:06Z")\
**Posts on this page:** 2\
**Page:** 1

<div class="post-metadata">

**Author:** ![SOFIA\_R](https://sea2.discourse-cdn.com/flex002/user_avatar/discourse.slicer.org/sofia_r/32/66469_2.png) [@SOFIA\_R](https://discourse.slicer.org/u/SOFIA_R)\
**Post date:** [August 31, 2023, 10:43pm UTC](https://discourse.slicer.org/t/undo-button-for-mistakes-in-segmentation/31486/1 "2023-08-31T22:43:06Z")

</div>

Hello, I’m doing a manual segmentation in 3D slicer and I made a mistake with the brush tool, how can i undo this action? There’s a yellow button in the segmentation module that seems to be an “undo option” but it doesn’t erase what I just drew in the image, there has to be a way to erase what you draw, just like in paint. Please help.

---

<div class="post-metadata">

**Author:** ![jamesobutler](https://sea2.discourse-cdn.com/flex002/user_avatar/discourse.slicer.org/jamesobutler/32/7511_2.png) [@jamesobutler](https://discourse.slicer.org/u/jamesobutler)\
**Post date:** [September 1, 2023, 12:09am UTC](https://discourse.slicer.org/t/undo-button-for-mistakes-in-segmentation/31486/2 "2023-09-01T00:09:41Z")

</div>

> [@Simple Undo button](https://discourse.slicer.org/t/simple-undo-button/10995/8):
>
> If you press the “undo” option and then move your mouse do you see it undo in the slice views? I have observed cases where pressing undo does not update the slice view until you move your mouse.

Did you happen to see my response on the other thread you posted on? Could you reply to my comment here so we can learn more details?