American Toad eye condition

I have an American toad, about 2 months ago i noticed her rubbing her eyes as if somethging were in them... she burrows alot so i dont see hertoo often.... now she came out of burrowing and her one eye is puffy... it looks like the eye lid is puffed out and swollen and she can barley open her eye.... she keeps trying to rub her eye and now she is having a hard time eating because of her eye... the actual eye ball itself is clear and deosnt looklike any problems but the lid that covers it looks puffy and watery.... anyone know what this could be caused from?