Is it just the one eye?
Could be a vitamin A issue. I had the same issue with one of my panthers. Started supplementing with vitamin A and it corrected itself. Please note, this needs to be done very slightly. It was about 5 years ago, but i took vitamin A liquid capsules, poked a hole and put a very small amount on a cricket once every few day for a few weeks. Then went to once a month.
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