Welcome to the forum.
If you are talking about a gif with one link and provided the
new image is the same size as the old one, you can just replace it
with RH closed provided you use the same name.
If you are talking about an image with mapped areas, then I
believe you have to start all over again. Worth trying though if
size and name are unchanged.
Do backup before you try anything or wait for someone who
regularly has that problem to come along and answer the question.
Help others by clicking Correct Answer if the question is answered. Found the answer elsewhere? Share it here. "Upvote" is for useful posts.