Spotted Molly With Swollen Ring Around The Eye

[FishKeeping]

Hi,
My molly has a swollen ring around one of its eyes and this has literally happened over night as she was fine yesterday. She seems to be her normal self at the moment and I'm not sure what this could be. I've read it could be pop eye but this seems a bit odd to me because of how quick its happened and the fact that the whole eye is not swollen; just around the edges. I am new to this site (with this being my first post) so any help would be appreciated and if more info is required let me know. Have also attached pictures, which is useful to compare both eyes together.
Many thanks

 

[Chad]

It is possible it could be an injury of some kind. Either another fish or from it being sucked against the filter.
 
However, it does look like pop eye to me.

 

[the_lock_man]

It seems to me that mollies are prone to this - when I kept them, I seemed to be constantly battling it. Cleaner water sorted it out pretty quickly - daily water changes for a few days.

 

[FishKeeping]

Ok thanks, I'll treat it for pop-eye and see what happens, would it need to be quarantined if I do this ? Also my mum has a goldfish that has pop-eye and she's treated it but it has never gone so am I to expect the same result? Also if it is an injury will it just go of its own accord (sorry for the many Qs). Just surprised to see this really because I had this fish for about a year now, so still new to this I suppose

 

[FishKeeping]

A few days after this post the eye returned to normal so must have been just an injury (to anyone else who may have this problem)