If an image is deleted that you commented on, then a random image takes the place of the deleted one. So even though that image is in your list you may never have visited it or commented on it.
Unless you have a more specific example of a deleted comment?
Maybe the admin just find you offensive
![smiling smiley smiling smiley](https://www.plus613.net/forum/mods/smileys/images/smilie1.gif)
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